COMPOSITIONS COMPRISING BACTERIAL STRAIN

TECHNICAL FIELD

This invention is in the field of compositions comprising a bacterial strain isolated from the mammalian digestive tract and the use of such compositions in the treatment of disease. BACKGROUND TO THE INVENTION

The human intestine is thought to be sterile in utero, but it is exposed to a large variety of maternal and environmental microbes immediately after birth. Thereafter, a dynamic period of microbial colonization and succession occurs, which is influenced by factors such as delivery mode, environment, diet and host genotype, all of which impact upon the composition of the gut microbiota, particularly during early life. Subsequently, the microbiota stabilizes and becomes adult -like [1]. The human gut microbiota contains more than 500-1000 different phylotypes belonging essentially to two major bacterial divisions, the Bacteroidetes and the Firmicutes [2]. The successful symbiotic relationships arising from bacterial colonization of the human gut have yielded a wide variety of metabolic, structural, protective and other beneficial functions. The enhanced metabolic activities of the colonized gut ensure that otherwise indigestible dietary components are degraded with release of by-products providing an important nutrient source for the host. Similarly, the immunological importance of the gut microbiota is well-recognized and is exemplified in germfree animals which have an impaired immune system that is functionally reconstituted following the introduction of commensal bacteria [3-5]. Dramatic changes in microbiota composition have been documented in gastrointestinal disorders such as inflammatory bowel disease (IBD). For example, the levels of Clostridium cluster XlVa bacteria are reduced in IBD patients whilst numbers of E. coli are increased, suggesting a shift in the balance of symbionts and pathobionts within the gut [6-9]. Interestingly, this microbial dysbiosis is also associated with imbalances in T effector cell populations.

In recognition of the potential positive effect that certain bacterial strains may have on the animal gut, various strains have been proposed for use in the treatment of various diseases (see, for example, [10- 13]). Also, certain strains, including mostly Lactobacillus and Bifidobacterium strains, have been proposed for use in treating various inflammatory and autoimmune diseases that are not directly linked to the intestines (see [14] and [15] for reviews). However, the relationship between different diseases and different bacterial strains, and the precise effects of particular bacterial strains on the gut and at a systemic level and on any particular types of diseases, are poorly characterised. For example, certain Enterococcus species have been implicated in causing cancer [16].

There is a requirement in the art for new methods of treating diseases. There is also a requirement for the potential effects of gut bacteria to be characterised so that new therapies using gut bacteria can be developed. SUMMARY OF THE INVENTION

The inventors have developed new therapies for treating and preventing diseases. In particular, the inventors have developed new therapies for treating and preventing cancer. In particular, the inventors have identified that a bacterial strain of the species Enterococcus gallinarum can be effective for treating and preventing cancer. As described in the examples, oral administration of compositions comprising this strain of Enterococcus gallinarum may reduce tumor size in mouse models of cancer.

According to a first aspect of the invention, there is provided an Enterococcus gallinarum deposited under accession number NCIMB 42761, or a derivative thereof.

In preferred embodiments, the invention provides a composition comprising an Enterococcus gallinarum deposited under accession number NCIMB 42761, or a derivative thereof, for use in a method of treating or preventing cancer, such as breast, lung or liver cancer. The inventors have identified that treatment with compositions comprising a bacterial strain of the species Enterococcus gallinarum deposited under accession number NCIMB 42761 can reduce tumour growth in mouse models of breast cancer. In certain embodiments, the composition is for use in a method of reducing tumour size or preventing tumour growth in the treatment of cancer. Compositions using the Enterococcus gallinarum strain of the invention may be particularly effective for reducing tumour size or preventing tumour growth in the treatment of cancer.

In certain embodiments, the composition of the invention is for oral administration. Oral administration of the strain of the invention can be effective for treating cancer. Also, oral administration is convenient for patients and practitioners and allows delivery to and / or partial or total colonisation of the intestine.

In certain embodiments, the composition of the invention comprises one or more pharmaceutically acceptable excipients or carriers.

In certain embodiments, the composition of the invention comprises a bacterial strain that has been lyophilised. Lyophilisation is an effective and convenient technique for preparing stable compositions that allow delivery of bacteria.

In certain embodiments, the invention provides a food product comprising the composition as described above.

In certain embodiments, the invention provides a vaccine composition comprising the composition as described above. Additionally, the invention provides a method of treating or preventing cancer, comprising administering a composition comprising a bacterial strain of the species Enterococcus gallinarum deposited under accession number NCIMB 42761.

In developing the above invention, the inventors have identified and characterised a bacterial strain that is particularly useful for therapy. The Enterococcus gallinarum strain of the invention is shown to be effective for treating cancer. The invention also provides compositions comprising such cells, or biologically pure cultures of such cells. The invention also provides a cell of the Enterococcus gallinarum strain deposited under accession number NCIMB 42761, or a derivative thereof, for use in therapy, in particular for cancer. BRIEF DESCRIPTION OF DRAWINGS

Figure 1: Mouse model of breast cancer - tumor volume.

Figure 2: API 50 CHL profile of MRx0554.

DISCLOSURE OF THE INVENTION

Bacterial strain

The compositions of the invention comprise a bacterial strain of the species Enterococcus gallinarum deposited under accession number NCIMB 42761. The examples demonstrate that the bacteria strain is useful for treating or preventing cancer.

The invention provides an Enterococcus gallinarum for use in therapy, for example, for use in treating or preventing cancer. Similarly, the invention provides a composition comprising a bacterial strain of the species Enterococcus gallinarum, for use in therapy, for example, for use in treating or preventing cancer.

Enterococcus gallinarum forms coccoid cells, mostly in pairs or short chains. It is nonmotile and colonies on blood agar or nutrient agar are circular and smooth. Enterococcus gallinarum reacts with Lancefield group D antisera. The type strain of Enterococcus gallinarum is F87/276 = PB21 = ATCC 49573 = CCUG 18658 = CIP 103013 = JCM 8728 = LMG 13129 = NBRC 100675 = NCIMB 702313 (formerly NCDO 2313) = NCTC 12359 [17]. The GenBank accession number for a 16S rRNA gene sequence of Enterococcus gallinarum is AF039900 (disclosed herein as SEQ ID NO: 1). An exemplary Enterococcus gallinarum strain is described in [17].

The Enterococcus gallinarum bacterium deposited under accession number NCIMB 42761 was tested in the Example and is also referred to herein as strain MRX554. References to MRX554 and MRx0554 are used interchangeably. Strain MRX554 was deposited with the international depositary authority NCIMB, Ltd. (Ferguson Building, Aberdeen, AB21 9YA, Scotland) by 4D Pharma Research Ltd. (Life Sciences Innovation Building, Aberdeen, AB25 2ZS, Scotland) on 22 May 2017 as "Enterococcus sp" and was assigned accession number NCIMB 42761. The genome sequence of this bacterium is disclosed herein as SEQ ID NO:2. The genome sequence was assembled from multiple contigs. Ns in the sequence represent gaps between the contigs. "N" may represent an A, G, C or T nucleotide. A 16S rRNA gene sequence for the MRX554 strain is provided in SEQ ID NO:3. SEQ ID NO:3 represents the full length sequence present in the assembly, rather than a consensus of the five 16S genes present in MRX554. Bacterial strains closely related to the strain tested in the examples are also expected to be effective for treating or preventing cancer. In certain embodiments, the bacterial strain for use in the invention has a 16s rRNA sequence that is at least 95%, 96%, 97%, 98%, 99%, 99.5% or 99.9% identical to the 16s rRNA sequence of the bacterium deposited under accession number NCIMB 42761. Preferably, the bacterial strain for use in the invention has a 16s rRNA gene sequence that is at least 95%, 96%, 97%, 98%, 99%, 99.5% or 99.9% identical to SEQ ID NO:l or 3. Preferably, the sequence identity is to SEQ ID NO:3. Preferably, the bacterial strain for use in the invention has the 16s rRNA gene sequence represented by SEQ ID NO:3.

Bacterial strains that are biotypes of the bacterium deposited under accession number 42761 are also expected to be effective for treating or preventing cancer. A biotype is a closely related strain that has the same or very similar physiological and biochemical characteristics.

Strains that are biotypes of the bacterium deposited under accession number NCIMB 42761 and that are suitable for use in the invention may be identified by sequencing other nucleotide sequences for the bacterium deposited under accession number NCIMB 42761. For example, substantially the whole genome may be sequenced and a biotype strain for use in the invention may have at least 95%, 96%, 97%, 98%, 99%, 99.5% or 99.9% sequence identity across at least 80% of its whole genome (e.g. across at least 85%, 90%, 95% or 99%, or across its whole genome). For example, in some embodiments, a biotype strain has at least 98% sequence identity across at least 98% of its genome or at least 99% sequence identity across 99% of its genome. Other suitable sequences for use in identifying biotype strains may include hsp60 or repetitive sequences such as BOX, ERIC, (GTG) ₅ , or REP or [18]. Biotype strains may have sequences with at least 95%, 96%, 97%, 98%, 99%, 99.5% or 99.9% sequence identity to the corresponding sequence of the bacterium deposited under accession number NCIMB 42761. In some embodiments, a biotype strain has a sequence with at least 95%, 96%, 97%, 98%, 99%, 99.5% or 99.9% sequence identity to the corresponding sequence of strain MRX554 deposited as NCIMB 42761. In some embodiments, a biotype strain has a sequence with at least 95%, 96%, 97%, 98%, 99%, 99.5% or 99.9% sequence identity to the corresponding sequence of strain MRX554 deposited as NCIMB 42761 and has a 16S rRNA gene sequence that is at least 99% identical (e.g. at least 99.5% or at least 99.9% identical) to SEQ ID NO:3. In some embodiments, a biotype strain has a sequence with at least 95%, 96%, 97%, 98%, 99%, 99.5% or 99.9% sequence identity to the corresponding sequence of strain MRX554 deposited as NCIMB 42761 and has the 16S rRNA gene sequence of SEQ ID NO:3.

Alternatively, strains that are biotypes of the bacterium deposited under accession number NCIMB 42761 and that are suitable for use in the invention may be identified by using the accession number NCIMB 42761 deposit and restriction fragment analysis and/or PCR analysis, for example by using fluorescent amplified fragment length polymorphism (FAFLP) and repetitive DNA element (rep)-PCR fingerprinting, or protein profiling, or partial 16S or 23s rDNA sequencing. In certain embodiments, strains that are biotypes of the bacterium deposited under accession number NCIMB 42761 and that are suitable for use in the invention are strains that provide the same pattern as the bacterium deposited under accession number NCIMB 42761 when analysed by amplified ribosomal DNA restriction analysis (ARDRA), for example when using Sau3AI restriction enzyme (for exemplary methods and guidance see, for example, [19]). Alternatively, biotype strains are identified as strains that have the same carbohydrate fermentation patterns as the bacterium deposited under accession number NCIMB 42761. In some embodiments, the carbohydrate fermentation pattern is determined using the API 50 CHL panel (bioMerieux). In some embodiments, the bacterial strain used in the invention is:

(i) positive for fermentation of at least one of (e.g. at least 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17 or all of): L-arabinose, D-ribose, D-xylose, D-galactose, D-glucose, D- fructose, D-mannose, N-acetylglucosamine, amygdalin, arbutin, salicin, D-cellobiose, D- maltose, sucrose, D-trehalose, gentiobiose, D-tagatose and potassium gluconate; and/or

(ii) intermediate for fermentation of at least one of (e.g. at least 2, 3, 4 or all of): D-mannitol, Methyl-aD-glycopyranoside, D-lactose, starch, and L-fucose;

preferably as determined by API 50 CHL analysis (preferably using the API 50 CHL panel from bioMerieux).

In some embodiments, the bacterial strain used in the invention is:

(i) positive for fermentation of at least one of (e.g. at least 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18 or all of): L-arabinose, D-ribose, D-xylose, D-galactose, D-glucose, D- fructose, D-mannose, N-acetylglucosamine, amygdalin, arbutin, esculin, salicin, D- cellobiose, D-maltose, D-saccharose (sucrose), D-trehalose, gentiobiose, D-tagatose and potassium gluconate;

(ii) intermediate for fermentation of at least one of (e.g. at least 2, 3, 4, 5 or all of): D-mannitol, Methyl-aD-glycopyranoside, D-lactose, D-raffinose, amidon (starch), and D-turanose; and/or

(iii) negative for fermentation of at least one of (e.g. at least 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23 or all of): glycerol, erythritol, D-arabinose, L-xylose, D-adonitol, methyl- D-xylopryranoside, L-sorbose, L-rhamnose, dulcitol, inositol, D- sorbitol, Methyl-aD-mannopyranoside, D-melibiose, inulin, D-melezitose, glycogen, xylitol, D-lyxose, D-fucose, L-fucose, D-arabitol, L-arabitol, potassium 2-ketogluconate and potassium 5-ketogluconate; preferably as determined by API 50 CHL analysis (preferably using the API 50 CHL panel from bioMerieux, and preferably using the conditions described in Example 3).

Other Enterococcus gallinarum strains that are useful in the compositions and methods of the invention, such as biotypes of the bacterium deposited under accession number NCIMB 42761, may be identified using any appropriate method or strategy, including the assays described in the examples. For instance, strain for use in the invention may be identified by culturing in anaerobic YCFA and/or administering the bacteria to the type II collagen-induced arthritis mouse model and then assessing cytokine levels. In particular, bacterial strains that have similar growth patterns, metabolic type and/or surface antigens to the bacterium deposited under accession number NCIMB 42761 may be useful in the invention. A useful strain will have comparable immune modulatory activity to the NCIMB 42761 strain. In particular, a biotype strain will elicit comparable effects on the cancer disease models to the effects shown in the Examples, which may be identified by using the culturing and administration protocols described in the Examples.

The invention further provides a cell, such as an isolated cell, of the Enterococcus gallinarum strain deposited under accession number NCIMB 42761, or a derivative thereof. The invention also provides a composition comprising a cell of the Enterococcus gallinarum strain deposited under accession number NCIMB 42761 , or a derivative thereof. The invention also provides a biologically pure culture of the Enterococcus gallinarum strain deposited under accession number NCIMB 42761. The invention also provides a cell of the Enterococcus gallinarum strain deposited under accession number NCIMB 42761, or a derivative thereof, for use in therapy, in particular for the diseases described herein. A derivative of the strain deposited under accession number NCIMB 42761 may be a daughter strain (progeny) or a strain cultured (subcloned) from the original.

A derivative of a strain of the invention may be modified, for example at the genetic level, without ablating the biological activity. In particular, a derivative strain of the invention is therapeutically active. A derivative strain will have comparable immune modulatory activity to the original NCIMB 42761 strain. In particular, a derivative strain will elicit comparable effects on the cancer disease models to the effects shown in the Examples, which may be identified by using the culturing and administration protocols described in the Examples. A derivative of the NCIMB 42761 strain will generally be a biotype of the NCIMB 42761 strain.

References to cells of the Enterococcus gallinarum strain deposited under accession number NCIMB 42761 encompass any cells that have the same safety and therapeutic efficacy characteristics as the strain deposited under accession number NCIMB 42761, and such cells are encompassed by the invention. Thus, in some embodiments, reference to cells of the Enterococcus gallinarum strain deposited under accession number NCIMB 42761 refers only to the MRX554 strain deposited under NCIMB 42761 and does not refer to a bacterial strain that was not deposited under NCIMB 42761.

In certain embodiments, the bacterial strain for use in the invention has a genome with sequence identity to SEQ ID NO:2. In some embodiments, the bacterial strain for use in the invention has a genome with at least 90% sequence identity (e.g. at least 92%, 94%, 95%, 96%, 97%, 98%, 99% or 100% sequence identity) to SEQ ID NO:2 across at least 60% (e.g. across at least 65%, 70%, 75%, 80%, 85%, 95%, 96%, 97%, 98%, 99% or 100%) of SEQ ID NO:2. For example, the bacterial strain for use in the invention may have a genome with at least 90% sequence identity to SEQ ID NO:2 across 70% of SEQ ID NO:2, or at least 90% sequence identity to SEQ ID NO:2 across 80% of SEQ ID NO:2, or at least 90% sequence identity to SEQ ID NO:2 across 90% of SEQ ID NO:2, or at least 90% sequence identity to SEQ ID NO:2 across 100% of SEQ ID NO:2, or at least 95% sequence identity to SEQ ID NO:2 across 70% of SEQ ID NO:2, or at least 95% sequence identity to SEQ ID NO:2 across 80% of SEQ ID NO:2, or at least 95% sequence identity to SEQ ID NO:2 across 90% of SEQ ID NO:2, or at least 95% sequence identity to SEQ ID NO:2 across 100% of SEQ ID NO:2, or at least 98% sequence identity to SEQ ID NO:2 across 70% of SEQ ID NO:2, or at least 98% sequence identity to SEQ ID NO:2 across 80% of SEQ ID NO:2, or at least 98% sequence identity to SEQ ID NO:2 across 90% of SEQ ID NO:2, or at least 98% identity across 95% of SEQ ID NO:2, or at least 98% sequence identity to SEQ ID NO:2 across 100% of SEQ ID NO:2, or at least 99.5% sequence identity to SEQ ID NO:2 across 90% of SEQ ID NO:2, or at least 99.5% identity across 95% of SEQ ID NO:2, or at least 99.5% identity across 98% of SEQ ID NO:2, or at least 99.5% sequence identity to SEQ ID NO:2 across 100% of SEQ ID NO:2.

In certain embodiments, the bacterial strain for use in the invention has a genome with sequence identity to SEQ ID NO:2, for example as described above, and a 16S rRNA gene sequence with sequence identity to SEQ ID NO:l or 3, for example as described above, preferably with a 16S rRNA gene sequence that is at least 99% identical to SEQ ID NO: 3, more preferably which comprises the 16S rRNA gene sequence of SEQ ID NO:3.

In certain embodiments, the bacterial strain for use in the invention has a genome with sequence identity to SEQ ID NO:2, for example as described above, and is effective for treating or preventing cancer.

In certain embodiments, the bacterial strain for use in the invention has a genome with sequence identity to SEQ ID NO:2, for example as described above, and a 16S rRNA gene sequence with sequence identity to SEQ ID NO: 1 or 3, for example as described above, and is effective for treating or preventing cancer.

In certain embodiments, the bacterial strain for use in the invention has a 16S rRNA gene sequence that is at least 99%, 99.5% or 99.9% identical to the 16S rRNA gene sequence represented by SEQ ID NO: 3 (for example, which comprises the 16S gene rRNA sequence of SEQ ID NO:2) and a genome with at least 95% sequence identity to SEQ ID NO:2 across at least 90% of SEQ ID NO:2, and which is effective for treating or preventing cancer.

In certain embodiments, the bacterial strain for use in the invention is a Enterococcus gallinarum and has a 16S rRNA gene sequence that is at least 99%, 99.5% or 99.9% identical to the 16S rRNA gene sequence represented by SEQ ID NO: 3 (for example, which comprises the 16S rRNA gene sequence of SEQ ID NO:3) and a genome with at least 98% sequence identity (e.g. at least 99% or at least 99.5% sequence identity) to SEQ ID NO:2 across at least 98% (e.g. across at least 99% or at least 99.5%) of SEQ ID NO:2, and which is effective for treating or preventing cancer.

In preferred embodiments, the bacterial strain in the compositions of the invention is viable and capable of partially or totally colonising the intestine.

Treating cancer

In preferred embodiments, the compositions of the invention are for use in treating or preventing cancer. The examples demonstrate that administration of the compositions of the invention can lead to a reduction in tumour growth in tumour models.

In certain embodiments, treatment with the compositions of the invention results in a reduction in tumour size or a reduction in tumour growth. In certain embodiments, the compositions of the invention are for use in reducing tumour size or reducing tumour growth. The compositions of the invention may be effective for reducing tumour size or growth. In certain embodiments, the compositions of the invention are for use in patients with solid tumours. In certain embodiments, the compositions of the invention are for use in reducing or preventing angiogenesis in the treatment of cancer. The compositions of the invention may have an effect on the immune or inflammatory systems, which have central roles in angiogenesis. In certain embodiments, the compositions of the invention are for use in preventing metastasis.

In preferred embodiments, the compositions of the invention are for use in treating or preventing breast cancer. The examples demonstrate that the compositions of the invention may be effective for treating breast cancer. In certain embodiments, the compositions of the invention are for use in reducing tumour size, reducing tumour growth, or reducing angiogenesis in the treatment of breast cancer. In preferred embodiments the cancer is mammary carcinoma. In preferred embodiments the cancer is stage IV breast cancer. In certain embodiments, the compositions of the invention are for use in treating or preventing lung cancer. The compositions of the invention may be effective for treating lung cancer. In certain embodiments, the compositions of the invention are for use in reducing tumour size, reducing tumour growth, or reducing angiogenesis in the treatment of lung cancer. In preferred embodiments the cancer is lung carcinoma.

In certain embodiments, the compositions of the invention are for use in treating or preventing liver cancer. The compositions of the invention may be effective for treating liver cancer. In certain embodiments, the compositions of the invention are for use in reducing tumour size, reducing tumour growth, or reducing angiogenesis in the treatment of liver cancer. In preferred embodiments the cancer is hepatoma (hepatocellular carcinoma). In certain embodiments, the compositions of the invention are for use in treating or preventing colon cancer. The compositions of the invention may have an effect on colon cancer cells and may be effective for treating colon cancer. In certain embodiments, the compositions of the invention are for use in reducing tumour size, reducing tumour growth, or reducing angiogenesis in the treatment of colon cancer. In preferred embodiments the cancer is colorectal adenocarcinoma.

In some embodiments, the cancer is of the intestine. In some embodiments, the cancer is of a part of the body which is not the intestine. In some embodiments, the cancer is not cancer of the intestine. In some embodiments, the cancer is not colorectal cancer. In some embodiments, the cancer is not cancer of the small intestine. In some embodiments, the treating or preventing occurs at a site other than at the intestine. In some embodiments, the treating or preventing occurs at the intestine and also at a site other than at the intestine.

In certain embodiments, the compositions of the invention are for use in treating or preventing carcinoma. The compositions of the invention may be effective for treating numerous types of carcinoma. In certain embodiments, the compositions of the invention are for use in treating or preventing non-immunogenic cancer. The examples demonstrate that the compositions of the invention may be effective for treating non-immunogenic cancers.

The therapeutic effects of the compositions of the invention on cancer may be mediated by a proinflammatory mechanism. The expression of a number of pro-inflammatory cytokines may be increased following administration of MRX554. Inflammation can have a cancer-suppressive effect [20] and pro-inflammatory cytokines such as TNFa are being investigated as cancer therapies [21]. The up-regulation of genes such as TNF may indicate that the compositions of the invention may be useful for treating cancer via a similar mechanism. The up-regulation of CXCR3 ligands (CXCL9, CXCL10) and IFNy-inducible genes (IL-32) may indicate that the compositions of the invention elicit an IFNy-type response. IFNy is a potent macrophage-activating factor that can stimulate tumirocidal activity [22], and CXCL9 and CXCL10, for example, also have anti-cancer effects [23-25]. Therefore, in certain embodiments, the compositions of the invention are for use in promoting inflammation in the treatment of cancer. In preferred embodiments, the compositions of the invention are for use in promoting Thl inflammation in the treatment of cancer. Thl cells produce IFNy and have potent anticancer effects [20]. In certain embodiments, the compositions of the invention are for use in treating an early-stage cancer, such as a cancer that has not metastasized, or a stage 0 or stage 1 cancer. Promoting inflammation may be more effective against early-stage cancers [20]. In certain embodiments, the compositions of the invention are for enhancing the effect of a second anti -cancer agent. In certain embodiments, the compositions of the invention are for use in promoting inflammation to enhance the effect of a second anti-cancer agent. In certain embodiments, the treatment or prevention of cancer comprises increasing the level of expression of one or more cytokines. For example, in certain embodiments, the treatment or prevention of cancer comprises increasing the level of expression of one or more of IL-Ιβ, IL-6 and TNF-a, for example, IL-Ιβ and IL-6, IL-Ιβ and TNF-a, IL-6 and TNF-a or all three of IL-Ιβ, IL-6 and TNF-a. Increases in levels of expression of any of IL-Ιβ, IL-6 and TNF-a are known to be indicative of efficacy in treatment of cancer.

When a bacterial strain as described herein is used in combination with lipopolysaccharide (LPS), there may be a synergistic increase in IL-Ιβ. LPS is known to elicit a pro-inflammatory effect. Thus, in certain embodiments, the treatment or prevention comprises using a bacterial strain as described herein in combination with an agent that upregulates IL-Ιβ. In certain embodiments, the treatment or prevention comprises using a bacterial strain as described herein in combination with LPS. Accordingly, a composition of the invention may additionally comprise an agent that upregulates IL- 1β. Accordingly, a composition of the invention may additionally comprise LPS.

In certain embodiments, the compositions of the invention are for use in treating a patient that has previously received chemotherapy. In certain embodiments, the compositions of the invention are for use in treating a patient that has not tolerated a chemotherapy treatment. The compositions of the invention may be particularly suitable for such patients.

In certain embodiments, the compositions of the invention are for preventing relapse. The compositions of the invention may be suitable for long-term administration. In certain embodiments, the compositions of the invention are for use in preventing progression of cancer.

In certain embodiments, the compositions of the invention are for use in treating non-small-cell lung carcinoma. In certain embodiments, the compositions of the invention are for use in treating small-cell lung carcinoma. In certain embodiments, the compositions of the invention are for use in treating squamous-cell carcinoma. In certain embodiments, the compositions of the invention are for use in treating adenocarcinoma. In certain embodiments, the compositions of the invention are for use in treating glandular tumors, carcinoid tumors, or undifferentiated carcinomas.

In certain embodiments, the compositions of the invention are for use in treating hepatoblastoma, cholangiocarcinoma, cholangiocellular cystadenocarcinoma or liver cancer resulting from a viral infection.

In certain embodiments, the compositions of the invention are for use in treating invasive ductal carcinoma, ductal carcinoma in situ or invasive lobular carcinoma.

In further embodiments, the compositions of the invention are for use in treating or preventing acute lymphoblastic leukemia (ALL), acute myeloid leukemia, adrenocortical carcinoma, basal-cell carcinoma, bile duct cancer, bladder cancer, bone tumor, osteosarcoma/malignant fibrous histiocytoma, brainstem glioma, brain tumor, cerebellar astrocytoma, cerebral astrocytoma/malignant glioma, ependymoma, medulloblastoma, supratentorial primitive neuroectodermal tumors, breast cancer, bronchial adenomas/carcinoids, Burkitt's lymphoma, carcinoid tumor, cervical cancer, chronic lymphocytic leukemia, chronic myelogenous leukemia, chronic myeloproliferative disorders, colon cancer, cutaneous T-cell lymphoma, endometrial cancer, ependymoma, esophageal cancer, Ewing's sarcoma, intraocular melanoma, retinoblastoma, gallbladder cancer, gastric cancer, gastrointestinal carcinoid tumor, gastrointestinal stromal tumor (GIST), germ cell tumor, glioma, childhood visual pathway and hypothalamic, Hodgkin lymphoma, melanoma, islet cell carcinoma, Kaposi sarcoma, renal cell cancer, laryngeal cancer, leukaemias, lymphomas, mesothelioma, neuroblastoma, non- Hodgkin lymphoma, oropharyngeal cancer, osteosarcoma, ovarian cancer, pancreatic cancer, parathyroid cancer, pharyngeal cancer, pituitary adenoma, plasma cell neoplasia, prostate cancer, renal cell carcinoma, retinoblastoma, sarcoma, testicular cancer, thyroid cancer, or uterine cancer.

The compositions of the invention may be particularly effective when used in combination with further therapeutic agents. The immune-modulatory effects of the compositions of the invention may be effective when combined with more direct anti-cancer agents. Therefore, in certain embodiments, the invention provides a composition comprising the bacterial strain of the species Enterococcus galhnarum and an anticancer agent. In certain embodiments, the composition of the invention comprising the bacterial strain of the species Enterococcus galhnarum is for use in stimulating a cancer to enhance its susceptibility to treatment with a second anti-cancer agent. In certain embodiments, the composition of the invention comprising the bacterial strain of the species Enterococcus galhnarum is for use in treating a cancer, such as a breast cancer, by enhancing its susceptibility to treatment with a second anti-cancer agent. The second antic-cancer agent may be administered concurrently, or may be administered after the composition comprising the bacterial strain of the species Enterococcus galhnarum, such as at least a day, a week, or a month after.

In preferred embodiments the anticancer agent is an immune checkpoint inhibitor, a targeted antibody immunotherapy, a CAR-T cell therapy, an oncolytic virus, or a cytostatic drug. In preferred embodiments, the composition comprises an anti-cancer agent selected from the group consisting of: Yervoy (ipilimumab, BMS); Keytruda (pembrolizumab, Merck); Opdivo (nivolumab, BMS); MEDI4736 (AZ/Medlmmune); MPDL3280A (Roche/Genentech); Tremelimumab (AZ/Medlmmune); CT-011 (pidilizumab, CureTech); BMS-986015 (lirilumab, BMS); MEDI0680 (AZ/Medlmmune); MSB-0010718C (Merck); PF-05082566 (Pfizer); MEDI6469 (AZ/Medlmmune); BMS-986016 (BMS); BMS-663513 (urelumab, BMS); IMP321 (Prima Biomed); LAG525 (Novartis); ARGX-110 (arGEN-X); PF-05082466 (Pfizer); CDX-1127 (varlilumab; CellDex Therapeutics); TRX-518 (GITR Inc.); MK-4166 (Merck); JTX-2011 (Jounce Therapeutics); ARGX-115 (arGEN-X); NLG-9189 (indoximod, NewLink Genetics); INCB024360 (Incyte); IPH2201 (Innate Immotherapeutics/AZ); NLG-919 (NewLink Genetics); anti-VISTA (JnJ); Epacadostat (INCB24360, Incyte); F001287 (Flexus/BMS); CP 870893 (University of Pennsylvania); MGA271 (Macrogenix); Emactuzumab (Roche/Genentech); Galunisertib (Eli Lilly); Ulocuplumab (BMS); BKT140/BL8040 (Biokine Therapeutics); Bavituximab (Peregrine Pharmaceuticals); CC 90002 (Celgene); 852A (Pfizer); VTX- 2337 (VentiRx Pharmaceuticals); IMO-2055 (Hybridon, Idera Pharmaceuticals); LY2157299 (Eli Lilly); EW-7197 (Ewha Women's University, Korea); Vemurafenib (Plexxikon); Dabrafenib (Genentech/GSK); BMS-777607 (BMS); BLZ945 (Memorial Sloan-Kettering Cancer Centre); Unituxin (dinutuximab, United Therapeutics Corporation); Blincyto (blinatumomab, Amgen); Cyramza (ramucirumab, Eli Lilly); Gazyva (obinutuzumab, Roche/Biogen); Kadcyla (ado- trastuzumab emtansine, Roche/Genentech); Perjeta (pertuzumab, Roche/Genentech); Adcetris (brentuximab vedotin, Takeda/Millennium); Arzerra (ofatumumab, GSK); Vectibix (panitumumab, Amgen); Avastin (bevacizumab, Roche/Genentech); Erbitux (cetuximab, BMS/Merck); Bexxar (tositumomab-1131, GSK); Zevalin (ibritumomab tiuxetan, Biogen); Campath (alemtuzumab, Bayer); Mylotarg (gemtuzumab ozogamicin, Pfizer); Herceptin (trastuzumab, Roche/Genentech); Rituxan (rituximab, Genentech/Biogen); volociximab (Abbvie); Enavatuzumab (Abbvie); ABT-414 (Abbvie); Elotuzumab (Abbvie/BMS); ALX-0141 (Ablynx); Ozaralizumab (Ablynx); Actimab-C (Actinium); Actimab-P (Actinium); Milatuzumab-dox (Actinium); Emab-SN-38 (Actinium); Naptumonmab estafenatox (Active Biotech); AFM13 (Affimed); AFM11 (Affimed); AGS-16C3F (Agensys); AGS- 16M8F (Agensys); AGS-22ME (Agensys); AGS-15ME (Agensys); GS-67E (Agensys); ALXN6000 (samalizumab, Alexion); ALT-836 (Altor Bioscience); ALT-801 (Altor Bioscience); ALT-803 (Altor Bioscience); AMG780 (Amgen); AMG 228 (Amgen); AMG820 (Amgen); AMG172 (Amgen); AMG595 (Amgen); AMG110 (Amgen); AMG232 (adecatumumab, Amgen); AMG211 (Amgen/Medlmmune); BAY20-10112 (Amgen/Bayer); Rilotumumab (Amgen); Denosumab (Amgen); AMP-514 (Amgen); MEDI575 (AZ/Medlmmune); MEDI3617 (AZ/Medlmmune); MEDI6383 (AZ/Medlmmune); MEDI551 (AZ/Medlmmune); Moxetumomab pasudotox (AZ/Medlmmune); MEDI565 (AZ/Medlmmune); MEDI0639 (AZ/Medlmmune); MEDI0680 (AZ/Medlmmune); MEDI562 (AZ/Medlmmune); AV-380 (AVEO); AV203 (AVEO); AV299 (AVEO); BAY79-4620 (Bayer); Anetumab ravtansine (Bayer); vantictumab (Bayer); BAY94-9343 (Bayer); Sibrotuzumab (Boehringer Ingleheim); BI-836845 (Boehringer Ingleheim); B-701 (BioClin); BIIB015 (Biogen); Obinutuzumab (Biogen/Genentech); BI-505 (Bioinvent); BI-1206 (Bioinvent); TB-403 (Bioinvent); BT-062 (Biotest) BIL-OlOt (Biosceptre); MDX-1203 (BMS); MDX-1204 (BMS); Necitumumab (BMS); CAN-4 (Cantargia AB); CDX-011 (Celldex); CDX1401 (Celldex); CDX301 (Celldex); U3-1565 (Daiichi Sankyo); patritumab (Daiichi Sankyo); tigatuzumab (Daiichi Sankyo); nimotuzumab (Daiichi Sankyo); DS-8895 (Daiichi Sankyo); DS-8873 (Daiichi Sankyo); DS- 5573 (Daiichi Sankyo); MORab-004 (Eisai); MORab-009 (Eisai); MORab-003 (Eisai); MORab-066 (Eisai); LY3012207 (Eli Lilly); LY2875358 (Eli Lilly); LY2812176 (Eli Lilly); LY3012217(Eli Lilly); LY2495655 (Eli Lilly); LY3012212 (Eli Lilly); LY3012211 (Eli Lilly); LY3009806 (Eli Lilly); cixutumumab (Eli Lilly); Flanvotumab (Eli Lilly); IMC-TR1 (Eli Lilly); Ramucirumab (Eli Lilly); Tabalumab (Eli Lilly); Zanolimumab (Emergent Biosolution); FG-3019 (FibroGen); FPA008 (Five Prime Therapeutics); FP-1039 (Five Prime Therapeutics); FPA144 (Five Prime Therapeutics); catumaxomab (Fresenius Biotech); IMAB362 (Ganymed); IMAB027 (Ganymed); HuMax-CD74 (Genmab); HuMax-TFADC (Genmab); GS-5745 (Gilead); GS-6624 (Gilead); OMP-21M18 (demcizumab, GSK); mapatumumab (GSK); IMGN289 (ImmunoGen); IMGN901 (ImmunoGen); IMGN853 (ImmunoGen); IMGN529 (ImmunoGen); IMMU-130 (Immunomedics); milatuzumab-dox (Immunomedics); IMMU-115 (Immunomedics); IMMU-132 (Immunomedics); IMMU-106 (Immunomedics); IMMU-102 (Immunomedics); Epratuzumab (Immunomedics); Clivatuzumab (Immunomedics); IPH41 (Innate Immunotherapeutics); Daratumumab (Janssen/Genmab); CNTO-95 (Intetumumab, Janssen); CNTO-328 (siltuximab, Janssen); KB004 (KaloBios); mogamulizumab (Kyowa Hakko Kirrin); KW-2871 (ecromeximab, Life Science); Sonepcizumab (Lpath); Margetuximab (Macrogenics); Enoblituzumab (Macrogenics); MGD006 (Macrogenics); MGF007 (Macrogenics); MK-0646 (dalotuzumab, Merck); MK-3475 (Merck); Sym004 (Symphogen/Merck Serono); DI17E6 (Merck Serono); MOR208 (Morphosys); MOR202 (Morphosys); Xmab5574 (Morphosys); BPC-1C (ensituximab, Precision Biologies); TAS266 (Novartis); LFA102 (Novartis); BHQ880 (Novartis/Morphosys); QGE031 (Novartis); HCD122 (lucatumumab, Novartis); LJM716 (Novartis); AT355 (Novartis); OMP-21M18 (Demcizumab, OncoMed); OMP52M51 (Oncomed/GSK); OMP-59R5 (Oncomed/GSK); vantictumab (Oncomed/Bayer); CMC-544 (inotuzumab ozogamicin, Pfizer); PF-03446962 (Pfizer); PF-04856884 (Pfizer); PSMA-ADC (Progenies); REGN1400 (Regeneron); REGN910 (nesvacumab, Regeneron/Sanofi); REGN421 (enoticumab, Regeneron/Sanofi); RG7221, RG7356, RG7155, RG7444, RG7116, RG7458, RG7598, RG7599, RG7600, RG7636, RG7450, RG7593, RG7596, DCDS3410A, RG7414 (parsatuzumab), RG7160 (imgatuzumab), RG7159 (obintuzumab), RG7686, RG3638 (onartuzumab), RG7597 (Roche/Genentech); SAR307746 (Sanofi); SAR566658 (Sanofi); SAR650984 (Sanofi); SAR153192 (Sanofi); SAR3419 (Sanofi); SAR256212 (Sanofi), SGN-LIV1A (lintuzumab, Seattle Genetics); SGN-CD33A (Seattle Genetics); SGN-75 (vorsetuzumab mafodotin, Seattle Genetics); SGN-19A (Seattle Genetics) SGN-CD70A (Seattle Genetics); SEA-CD40 (Seattle Genetics); ibritumomab tiuxetan (Spectrum); MLN0264 (Takeda); ganitumab (Takeda/Amgen); CEP-37250 (Teva); TB-403 (Thrombogenic); VB4-845 (Viventia); Xmab2512 (Xencor); Xmab5574 (Xencor); nimotuzumab (YM Biosciences); Carlumab (Janssen); NY-ESO TCR (Adaptimmune); MAGE- A- 10 TCR (Adaptimmune); CTL019 (Novartis); JCAR015 (Juno Therapeutics); KTE-C19 CAR (Kite Pharma); UCART19 (Cellectis); BPX-401 (Bellicum Pharmaceuticals); BPX-601 (Bellicum Pharmaceuticals); ATTCK20 (Unum Therapeutics); CAR-NKG2D (Celyad); Onyx-015 (Onyx Pharmaceuticals); H101 (Shanghai Sunwaybio); DNX-2401 (DNAtrix); VCN-01 (VCN Biosciences); Colo-Adl (PsiOxus Therapeutics); ProstAtak (Advantagene); Oncos-102 (Oncos Therapeutics); CG0070 (Cold Genesys); Pexa-vac (JX-594, Jennerex Biotherapeutics); GL-ONC1 (Genelux); T-VEC (Amgen); G207 (Medigene); HF10 (Takara Bio); SEPREHVIR (HSV1716, Virttu Biologies); OrienXOlO (OrienGene Biotechnology); Reolysin (Oncolytics Biotech); SVV-001 (Neotropix); Cacatak (CVA21, Viralytics); Alimta (Eli Lilly), cisplatin, oxaliplatin, irinotecan, folinic acid, methotrexate, cyclophosphamide, 5- fluorouracil, Zykadia (Novartis), Tafinlar (GSK), Xalkori (Pfizer), Iressa (AZ), Gilotrif (Boehringer Ingelheim), Tarceva (Astellas Pharma), Halaven (Eisai Pharma), Veliparib (Abbvie), AZD9291 (AZ), Alectinib (Chugai), LDK378 (Novartis), Genetespib (Synta Pharma), Tergenpumatucel-L (NewLink Genetics), GV1001 (Kael-GemVax), Tivantinib (ArQule); Cytoxan (BMS); Oncovin (Eli Lilly); Adriamycin (Pfizer); Gemzar (Eli Lilly); Xeloda (Roche); Ixempra (BMS); Abraxane (Celgene); Trelstar (Debiopharm); Taxotere (Sanofi); Nexavar (Bayer); IMMU-132 (Immunomedics); E7449 (Eisai); Thermodox (Celsion); Cometriq (Exellxis); Lonsurf (Taiho Pharmaceuticals); Camptosar (Pfizer); UFT (Taiho Pharmaceuticals); and TS-1 (Taiho Pharmaceuticals).

In some embodiments, the bacterial strain of Enterococcus gallinarum deposited under accession number NCIMB 42761 is the only therapeutically active agent in a composition of the invention.

Modes of administration

Preferably, the compositions of the invention are to be administered to the gastrointestinal tract in order to enable delivery to and / or partial or total colonisation of the intestine with the bacterial strain of the invention. Generally, the compositions of the invention are administered orally, but they may be administered rectally, intranasally, or via buccal or sublingual routes.

In certain embodiments, the compositions of the invention may be administered as a foam, as a spray or a gel.

In certain embodiments, the compositions of the invention may be administered as a suppository, such as a rectal suppository, for example in the form of a theobroma oil (cocoa butter), synthetic hard fat (e.g. suppocire, witepsol), glycero-gelatin, polyethylene glycol, or soap glycerin composition.

In certain embodiments, the composition of the invention is administered to the gastrointestinal tract via a tube, such as a nasogastric tube, orogastric tube, gastric tube, jejunostomy tube (J tube), percutaneous endoscopic gastrostomy (PEG), or a port, such as a chest wall port that provides access to the stomach, jejunum and other suitable access ports. The compositions of the invention may be administered once, or they may be administered sequentially as part of a treatment regimen. In certain embodiments, the compositions of the invention are to be administered daily.

In certain embodiments of the invention, treatment according to the invention is accompanied by assessment of the patient's gut microbiota. Treatment may be repeated if delivery of and / or partial or total colonisation with the strain of the invention is not achieved such that efficacy is not observed, or treatment may be ceased if delivery and / or partial or total colonisation is successful and efficacy is observed.

In certain embodiments, the composition of the invention may be administered to a pregnant animal, for example a mammal such as a human in order to reduce the likelihood of cancer developing in her child in utero and / or after it is born.

The compositions of the invention may be administered to a patient that has been diagnosed with cancer, or that has been identified as being at risk of a cancer. The compositions may also be administered as a prophylactic measure to prevent the development of cancer in a healthy patient. The compositions of the invention may be administered to a patient that has been identified as having an abnormal gut microbiota. For example, the patient may have reduced or absent colonisation by Enterococcus gallinarum.

The compositions of the invention may be administered as a food product, such as a nutritional supplement.

Generally, the compositions of the invention are for the treatment of humans, although they may be used to treat animals including monogastric mammals such as poultry, pigs, cats, dogs, horses or rabbits. The compositions of the invention may be useful for enhancing the growth and performance of animals. If administered to animals, oral gavage may be used. Compositions

Generally, the composition of the invention comprises bacteria. In preferred embodiments of the invention, the composition is formulated in freeze -dried form. For example, the composition of the invention may comprise granules or gelatin capsules, for example hard gelatin capsules, comprising a bacterial strain of the invention.

Preferably, the composition of the invention comprises lyophilised bacteria. Lyophilisation of bacteria is a well-established procedure and relevant guidance is available in, for example, references [26-28].

Alternatively, the composition of the invention may comprise a live, active bacterial culture.

In some embodiments, the bacterial strain in the composition of the invention has not been inactivated, for example, has not been heat-inactivated. In some embodiments, the bacterial strain in the composition of the invention has not been killed, for example, has not been heat -killed. In some embodiments, the bacterial strain in the composition of the invention has not been attenuated, for example, has not been heat-attenuated. For example, in some embodiments, the bacterial strain in the composition of the invention has not been killed, inactivated and/or attenuated. For example, in some embodiments, the bacterial strain in the composition of the invention is live. For example, in some embodiments, the bacterial strain in the composition of the invention is viable. For example, in some embodiments, the bacterial strain in the composition of the invention is capable of partially or totally colonising the intestine. For example, in some embodiments, the bacterial strain in the composition of the invention is viable and capable of partially or totally colonising the intestine.

In some embodiments, the composition comprises a mixture of live bacterial strains and bacterial strains that have been killed.

In preferred embodiments, the composition of the invention is encapsulated to enable delivery of the bacterial strain to the intestine. Encapsulation protects the composition from degradation until delivery at the target location through, for example, rupturing with chemical or physical stimuli such as pressure, enzymatic activity, or physical disintegration, which may be triggered by changes in pH. Any appropriate encapsulation method may be used. Exemplary encapsulation techniques include entrapment within a porous matrix, attachment or adsorption on solid carrier surfaces, self-aggregation by flocculation or with cross-linking agents, and mechanical containment behind a microporous membrane or a microcapsule. Guidance on encapsulation that may be useful for preparing compositions of the invention is available in, for example, references [29] and [30].

The composition may be administered orally and may be in the form of a tablet, capsule or powder. Encapsulated products are preferred because Enterococcus gallinarum are anaerobes. Other ingredients (such as vitamin C, for example), may be included as oxygen scavengers and prebiotic substrates to improve the delivery and / or partial or total colonisation and survival in vivo. Alternatively, the probiotic composition of the invention may be administered orally as a food or nutritional product, such as milk or whey based fermented dairy product, or as a pharmaceutical product.

The composition may be formulated as a probiotic.

A composition of the invention includes a therapeutically effective amount of a bacterial strain of the invention. A therapeutically effective amount of a bacterial strain is sufficient to exert a beneficial effect upon a patient. A therapeutically effective amount of a bacterial strain may be sufficient to result in delivery to and / or partial or total colonisation of the patient's intestine.

A suitable daily dose of the bacteria, for example for an adult human, may be from about 1 x 10 ³ to about 1 x 10 ¹¹ colony forming units (CFU); for example, from about 1 x 10 ⁷ to about 1 x 10 ¹⁰ CFU; in another example from about 1 x 10 ⁶ to about 1 x 10 ¹⁰ CFU.

In certain embodiments, the composition contains the bacterial strain in an amount of from about 1 x 10 ⁶ to about 1 x 10 ¹¹ CFU/g, respect to the weight of the composition; for example, from about 1 x 10 ⁸ to about 1 x 10 ¹⁰ CFU/g. The dose may be, for example, 1 g, 3g, 5g, and lOg.

Typically, a probiotic, such as the composition of the invention, is optionally combined with at least one suitable prebiotic compound. A prebiotic compound is usually a non-digestible carbohydrate such as an oligo- or polysaccharide, or a sugar alcohol, which is not degraded or absorbed in the upper digestive tract. Known prebiotics include commercial products such as inulin and transgalacto- oligosaccharides.

In certain embodiments, the probiotic composition of the present invention includes a prebiotic compound in an amount of from about 1 to about 30% by weight, respect to the total weight composition, (e.g. from 5 to 20% by weight). Carbohydrates may be selected from the group consisting of: fructo- oligosaccharides (or FOS), short-chain fructo-oligosaccharides, inulin, isomalt- oligosaccharides, pectins, xylo-oligosaccharides (or XOS), chitosan-oligosaccharides (or COS), beta- glucans, arable gum modified and resistant starches, polydextrose, D-tagatose, acacia fibers, carob, oats, and citrus fibers. In one aspect, the prebiotics are the short -chain fructo-oligosaccharides (for simplicity shown herein below as FOSs-c.c); said FOSs-c.c. are not digestible carbohydrates, generally obtained by the conversion of the beet sugar and including a saccharose molecule to which three glucose molecules are bonded.

The compositions of the invention may comprise pharmaceutically acceptable excipients or carriers. Examples of such suitable excipients may be found in the reference [31]. Acceptable carriers or diluents for therapeutic use are well known in the pharmaceutical art and are described, for example, in reference [32]. Examples of suitable carriers include lactose, starch, glucose, methyl cellulose, magnesium stearate, mannitol, sorbitol and the like. Examples of suitable diluents include ethanol, glycerol and water. The choice of pharmaceutical carrier, excipient or diluent can be selected with regard to the intended route of administration and standard pharmaceutical practice. The pharmaceutical compositions may comprise as, or in addition to, the carrier, excipient or diluent any suitable binder(s), lubricant(s), suspending agent(s), coating agent(s), solubilising agent(s). Examples of suitable binders include starch, gelatin, natural sugars such as glucose, anhydrous lactose, free -flow lactose, beta-lactose, corn sweeteners, natural and synthetic gums, such as acacia, tragacanth or sodium alginate, carboxymethyl cellulose and polyethylene glycol. Examples of suitable lubricants include sodium oleate, sodium stearate, magnesium stearate, sodium benzoate, sodium acetate, sodium chloride and the like. Preservatives, stabilizers, dyes and even flavouring agents may be provided in the pharmaceutical composition. Examples of preservatives include sodium benzoate, sorbic acid and esters of p-hydroxybenzoic acid. Antioxidants and suspending agents may be also used.

The compositions of the invention may be formulated as a food product. For example, a food product may provide nutritional benefit in addition to the therapeutic effect of the invention, such as in a nutritional supplement. Similarly, a food product may be formulated to enhance the taste of the composition of the invention or to make the composition more attractive to consume by being more similar to a common food item, rather than to a pharmaceutical composition. In certain embodiments, the composition of the invention is formulated as a milk-based product. The term "milk-based product" means any liquid or semi-solid milk- or whey- based product having a varying fat content. The milk- based product can be, e.g., cow's milk, goat's milk, sheep's milk, skimmed milk, whole milk, milk recombined from powdered milk and whey without any processing, or a processed product, such as yoghurt, curdled milk, curd, sour milk, sour whole milk, butter milk and other sour milk products. Another important group includes milk beverages, such as whey beverages, fermented milks, condensed milks, infant or baby milks; flavoured milks, ice cream; milk-containing food such as sweets.

In certain embodiments, the compositions of the invention contain a single bacterial strain or species and do not contain any other bacterial strains or species. Such compositions may comprise only de minimis or biologically irrelevant amounts of other bacterial strains or species. Such compositions may be a culture that is substantially free from other species of organism. Thus, in some embodiments, the invention provides a composition comprising one or more strains from the species Enterococcus gallinarum, which does not contain bacteria from any other species or which comprises only de minimis or biologically irrelevant amounts of bacteria from another species for use in therapy.

In some embodiments, the compositions of the invention comprise more than one bacterial strain or species. For example, in some embodiments, the compositions of the invention comprise more than one strain from within the same species (e.g. more than 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40 or 45 strains), and, optionally, do not contain bacteria from any other species. In some embodiments, the compositions of the invention comprise less than 50 strains from within the same species (e.g. less than 45, 40, 35, 30, 25, 20, 15, 12, 10, 9, 8, 7, 6, 5, 4 or 3 strains), and, optionally, do not contain bacteria from any other species. In some embodiments, the compositions of the invention comprise 1-40, 1-30, 1-20, 1-19, 1-18, 1-15, 1-10, 1-9, 1-8, 1-7, 1-6, 1-5, 1-4, 1-3, 1-2, 2-50, 2-40, 2- 30, 2-20, 2-15, 2-10, 2-5, 6-30, 6-15, 16-25, or 31-50 strains from within the same species and, optionally, do not contain bacteria from any other species. In some embodiments, the compositions of the invention comprise more than one species from within the same genus (e.g. more than 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 15, 17, 20, 23, 25, 30, 35 or 40 species), and, optionally, do not contain bacteria from any other genus. In some embodiments, the compositions of the invention comprise less than 50 species from within the same genus (e.g. less than 50, 45, 40, 35, 30, 25, 20, 15, 12, 10, 8, 7, 6, 5, 4 or 3 species), and, optionally, do not contain bacteria from any other genus. In some embodiments, the compositions of the invention comprise 1-50, 1-40, 1-30, 1-20, 1-15, 1-10, 1-9, 1-8, 1-7, 1-6, 1-5, 1-4, 1-3, 1-2, 2-50, 2-40, 2-30, 2-20, 2-15, 2-10, 2-5, 6-30, 6-15, 16-25, or 31-50 species from within the same genus and, optionally, do not contain bacteria from any other genus. The invention comprises any combination of the foregoing.

In some embodiments, the composition comprises a microbial consortium. For example, in some embodiments, the composition comprises the bacterial strain of Enterococcus gallinarum deposited under accession number NCIMB 42761, as part of a microbial consortium. For example, in some embodiments, the bacterial strain is present in combination with one or more (e.g. at least 2, 3, 4, 5, 10, 15 or 20) other bacterial strains from other genera with which it can live symbiotically in vivo in the intestine. For example, in some embodiments, the composition comprises a bacterial strain of Enterococcus gallinarum deposited under accession number NCIMB 42761, in combination with a bacterial strain from a different genus. In some embodiments, the microbial consortium comprises two or more bacterial strains obtained from a faeces sample of a single organism, e.g. a human. In some embodiments, the microbial consortium is not found together in nature. For example, in some embodiments, the microbial consortium comprises bacterial strains obtained from faeces samples of at least two different organisms. In some embodiments, the two different organisms are from the same species, e.g. two different humans, e.g. two different human infants. In some embodiments, the two different organisms are an infant human and an adult human. In some embodiments, the two different organisms are a human and a non-human mammal. In some embodiments, the composition of the invention additionally comprises a bacterial strain that has the same safety and therapeutic efficacy characteristics as strain MRX554, but which is not MRX554 deposited as NCIMB 42761, or which is not an Enterococcus gallinarum.

In some embodiments in which the composition of the invention comprises more than one bacterial strain, species or genus, the individual bacterial strains, species or genera may be for separate, simultaneous or sequential administration. For example, the composition may comprise all of the more than one bacterial strain, species or genera, or the bacterial strains, species or genera may be stored separately and be administered separately, simultaneously or sequentially. In some embodiments, the more than one bacterial strains, species or genera are stored separately but are mixed together prior to use.

In some embodiments, the bacterial strain for use in the invention is obtained from human infant faeces. In some embodiments in which the composition of the invention comprises more than one bacterial strain, all of the bacterial strains are obtained from human infant faeces or if other bacterial strains are present they are present only in de minimis amounts. The bacteria may have been cultured subsequent to being obtained from the human infant faeces and being used in a composition of the invention.

As mentioned above, in some embodiments, the bacterial strain of Enterococcus gallinarum deposited under accession number NCIMB 42761, is the only therapeutically active agent in a composition of the invention. In some embodiments, the bacterial strain in the composition is the only therapeutically active agent in a composition of the invention. The compositions for use in accordance with the invention may or may not require marketing approval.

In certain embodiments, the invention provides the above pharmaceutical composition, wherein said bacterial strain is lyophilised. In certain embodiments, the invention provides the above pharmaceutical composition, wherein said bacterial strain is spray dried. In certain embodiments, the invention provides the above pharmaceutical composition, wherein the bacterial strain is lyophilised or spray dried and wherein it is live. In certain embodiments, the invention provides the above pharmaceutical composition, wherein the bacterial strain is lyophilised or spray dried and wherein it is viable. In certain embodiments, the invention provides the above pharmaceutical composition, wherein the bacterial strain is lyophilised or spray dried and wherein it is capable of partially or totally colonising the intestine. In certain embodiments, the invention provides the above pharmaceutical composition, wherein the bacterial strain is lyophilised or spray dried and wherein it is viable and capable of partially or totally colonising the intestine.

In some cases, the lyophilised or spray dried bacterial strain is reconstituted prior to administration. In some cases, the reconstitution is by use of a diluent described herein.

The compositions of the invention can comprise pharmaceutically acceptable excipients, diluents or carriers. In certain embodiments, the invention provides a pharmaceutical composition comprising: a bacterial strain as used in the invention; and a pharmaceutically acceptable excipient, carrier or diluent; wherein the bacterial strain is in an amount sufficient to treat a disorder when administered to a subject in need thereof; and wherein the disorder is breast cancer. In preferred embodiments the cancer is mammary carcinoma. In preferred embodiments the cancer is stage IV breast cancer.

In certain embodiments, the invention provides a pharmaceutical composition comprising: a bacterial strain as used in the invention; and a pharmaceutically acceptable excipient, carrier or diluent; wherein the bacterial strain is in an amount sufficient to treat a disorder when administered to a subject in need thereof; and wherein the disorder is lung cancer. In preferred embodiments the cancer is lung carcinoma.

In certain embodiments, the invention provides a pharmaceutical composition comprising: a bacterial strain as used in the invention; and a pharmaceutically acceptable excipient, carrier or diluent; wherein the bacterial strain is in an amount sufficient to treat a disorder when administered to a subject in need thereof; and wherein the disorder is liver cancer. In preferred embodiments the cancer is hepatoma (hepatocellular carcinoma).

In certain embodiments, the invention provides a pharmaceutical composition comprising: a bacterial strain of the invention; and a pharmaceutically acceptable excipient, carrier or diluent; wherein the bacterial strain is in an amount sufficient to treat a disorder when administered to a subject in need thereof; and wherein the disorder is colon cancer. In preferred embodiments the cancer is colorectal adenocarcinoma.

In certain embodiments, the invention provides a pharmaceutical composition comprising: a bacterial strain of the invention; and a pharmaceutically acceptable excipient, carrier or diluent; wherein the bacterial strain is in an amount sufficient to treat a disorder when administered to a subject in need thereof; and wherein the disorder is carcinoma.

In certain embodiments, the invention provides a pharmaceutical composition comprising: a bacterial strain of the invention; and a pharmaceutically acceptable excipient, carrier or diluent; wherein the bacterial strain is in an amount sufficient to treat a disorder when administered to a subject in need thereof; and wherein the disorder is a non-immunogenic cancer.

In certain embodiments, the invention provides a pharmaceutical composition comprising: a bacterial strain of the invention; and a pharmaceutically acceptable excipient, carrier or diluent; wherein the bacterial strain is in an amount sufficient to treat a disorder when administered to a subject in need thereof; and wherein the disorder is selected from the group consisting of non-small-cell lung carcinoma, small-cell lung carcinoma, squamous-cell carcinoma, adenocarcinoma, glandular tumors, carcinoid tumors undifferentiated carcinomas. In certain embodiments, the invention provides a pharmaceutical composition comprising: a bacterial strain of the invention; and a pharmaceutically acceptable excipient, carrier or diluent; wherein the bacterial strain is in an amount sufficient to treat a disorder when administered to a subject in need thereof; and wherein the disorder is selected from the group consisting of hepatoblastoma, cholangiocarcinoma, cholangiocellular cystadenocarcinoma or liver cancer resulting from a viral infection.

In certain embodiments, the invention provides a pharmaceutical composition comprising: a bacterial strain of the invention; and a pharmaceutically acceptable excipient, carrier or diluent; wherein the bacterial strain is in an amount sufficient to treat a disorder when administered to a subject in need thereof; and wherein the disorder is selected from the group consisting of invasive ductal carcinoma, ductal carcinoma in situ or invasive lobular carcinoma.

In certain embodiments, the invention provides a pharmaceutical composition comprising: a bacterial strain of the invention; and a pharmaceutically acceptable excipient, carrier or diluent; wherein the bacterial strain is in an amount sufficient to treat a disorder when administered to a subject in need thereof; and wherein the disorder is selected from the group consisting of acute lymphoblastic leukemia (ALL), acute myeloid leukemia, adrenocortical carcinoma, basal-cell carcinoma, bile duct cancer, bladder cancer, bone tumor, osteosarcoma/malignant fibrous histiocytoma, brainstem glioma, brain tumor, cerebellar astrocytoma, cerebral astrocytoma/malignant glioma, ependymoma, medulloblastoma, supratentorial primitive neuroectodermal tumors, breast cancer, bronchial adenomas/carcinoids, Burkitt's lymphoma, carcinoid tumor, cervical cancer, chronic lymphocytic leukemia, chronic myelogenous leukemia, chronic myeloproliferative disorders, colon cancer, cutaneous T-cell lymphoma, endometrial cancer, ependymoma, esophageal cancer, Ewing's sarcoma, intraocular melanoma, retinoblastoma, gallbladder cancer, gastric cancer, gastrointestinal carcinoid tumor, gastrointestinal stromal tumor (GIST), germ cell tumor, glioma, childhood visual pathway and hypothalamic, Hodgkin lymphoma, melanoma, islet cell carcinoma, Kaposi sarcoma, renal cell cancer, laryngeal cancer, leukaemias, lymphomas, mesothelioma, neuroblastoma, non-Hodgkin lymphoma, oropharyngeal cancer, osteosarcoma, ovarian cancer, pancreatic cancer, parathyroid cancer, pharyngeal cancer, pituitary adenoma, plasma cell neoplasia, prostate cancer, renal cell carcinoma, retinoblastoma, sarcoma, testicular cancer, thyroid cancer, or uterine cancer.

In certain embodiments, the invention provides the above pharmaceutical composition, wherein the amount of the bacterial strain is from about 1 x 10 ³ to about 1 x 10 ¹¹ colony forming units per gram with respect to a weight of the composition.

In certain embodiments, the invention provides the above pharmaceutical composition, wherein the composition is administered at a dose of 1 g, 3 g, 5 g or 10 g. In certain embodiments, the invention provides the above pharmaceutical composition, wherein the composition is administered by a method selected from the group consisting of oral, rectal, subcutaneous, nasal, buccal, and sublingual.

In certain embodiments, the invention provides the above pharmaceutical composition, comprising a carrier selected from the group consisting of lactose, starch, glucose, methyl cellulose, magnesium stearate, mannitol and sorbitol.

In certain embodiments, the invention provides the above pharmaceutical composition, comprising a diluent selected from the group consisting of ethanol, glycerol and water.

In certain embodiments, the invention provides the above pharmaceutical composition, comprising an excipient selected from the group consisting of starch, gelatin, glucose, anhydrous lactose, free-flow lactose, beta-lactose, corn sweetener, acacia, tragacanth, sodium alginate, carboxymethyl cellulose, polyethylene glycol, sodium oleate, sodium stearate, magnesium stearate, sodium benzoate, sodium acetate and sodium chloride.

In certain embodiments, the invention provides the above pharmaceutical composition, further comprising at least one of a preservative, an antioxidant and a stabilizer.

In certain embodiments, the invention provides the above pharmaceutical composition, comprising a preservative selected from the group consisting of sodium benzoate, sorbic acid and esters of p- hydroxybenzoic acid.

In certain embodiments, the invention provides the above pharmaceutical composition, wherein when the composition is stored in a sealed container at about 4°C or about 25°C and the container is placed in an atmosphere having 50% relative humidity, at least 80% of the bacterial strain as measured in colony forming units, remains after a period of at least about: 1 month, 3 months, 6 months, 1 year, 1.5 years, 2 years, 2.5 years or 3 years.

In some embodiments, the composition of the invention is provided in a sealed container comprising a composition as described herein. In some embodiments, the sealed container is a sachet or bottle. In some embodiments, the composition of the invention is provided in a syringe comprising a composition as described herein.

The composition of the present invention may, in some embodiments, be provided as a pharmaceutical formulation. For example, the composition may be provided as a tablet or capsule. In some embodiments, the capsule is a gelatine capsule ("gel-cap").

In some embodiments, the compositions of the invention are administered orally. Oral administration may involve swallowing, so that the compound enters the gastrointestinal tract, and/or buccal, lingual, or sublingual administration by which the compound enters the blood stream directly from the mouth. Pharmaceutical formulations suitable for oral administration include solid plugs, solid microparticulates, semi-solid and liquid (including multiple phases or dispersed systems) such as tablets; soft or hard capsules containing multi- or nano-particulates, liquids (e.g. aqueous solutions), emulsions or powders; lozenges (including liquid-filled); chews; gels; fast dispersing dosage forms; films; ovules; sprays; and buccal/mucoadhesive patches.

In some embodiments the pharmaceutical formulation is an enteric formulation, i.e. a gastro -resistant formulation (for example, resistant to gastric pH) that is suitable for delivery of the composition of the invention to the intestine by oral administration. Enteric formulations may be particularly useful when the bacteria or another component of the composition is acid-sensitive, e.g. prone to degradation under gastric conditions.

In some embodiments, the enteric formulation comprises an enteric coating. In some embodiments, the formulation is an enteric -coated dosage form. For example, the formulation may be an enteric- coated tablet or an enteric-coated capsule, or the like. The enteric coating may be a conventional enteric coating, for example, a conventional coating for a tablet, capsule, or the like for oral delivery. The formulation may comprise a film coating, for example, a thin film layer of an enteric polymer, e.g. an acid-insoluble polymer.

In some embodiments, the enteric formulation is intrinsically enteric, for example, gastro -resistant without the need for an enteric coating. Thus, in some embodiments, the formulation is an enteric formulation that does not comprise an enteric coating. In some embodiments, the formulation is a capsule made from a thermogelling material. In some embodiments, the thermogelling material is a cellulosic material, such as methylcellulose, hydroxymethylcellulose or hydroxypropylmethylcellulose (HPMC). In some embodiments, the capsule comprises a shell that does not contain any film forming polymer. In some embodiments, the capsule comprises a shell and the shell comprises hydroxypropylmethylcellulose and does not comprise any film forming polymer (e.g. see [33 ]). In some embodiments, the formulation is an intrinsically enteric capsule (for example, Vcaps® from Capsugel).

In some embodiments, the formulation is a soft capsule. Soft capsules are capsules which may, owing to additions of softeners, such as, for example, glycerol, sorbitol, maltitol and polyethylene glycols, present in the capsule shell, have a certain elasticity and softness. Soft capsules can be produced, for example, on the basis of gelatine or starch. Gelatine -based soft capsules are commercially available from various suppliers. Depending on the method of administration, such as, for example, orally or rectally, soft capsules can have various shapes, they can be, for example, round, oval, oblong or torpedo-shaped. Soft capsules can be produced by conventional processes, such as, for example, by the Scherer process, the Accogel process or the droplet or blowing process. Culturing methods

The bacterial strain for use in the present invention can be cultured using standard microbiology techniques as detailed in, for example, references [34-36].

The solid or liquid medium used for culture may be YCFA agar or YCFA medium. YCFA medium may include (per 100ml, approximate values): Casitone (1.0 g), yeast extract (0.25 g), NaHCC (0.4 g), cysteine (0.1 g), K ₂ HP0 ₄ (0.045 g), KH ₂ P0 ₄ (0.045 g), NaCl (0.09 g), (NH ₄ ) ₂ S0 ₄ (0.09 g), MgS0 ₄ • 7H ₂ 0 (0.009 g), CaCl ₂ (0.009 g), resazurin (0.1 mg), hemin (1 mg), biotin (1 μg), cobalamin (1 μg), p-aminobenzoic acid (3 μg), folic acid (5 μg), and pyridoxamine (15 μg).

Bacterial strain for use in vaccine compositions

The inventors have identified that the bacterial strain of the invention is useful for treating or preventing cancer. This is likely to be a result of the effect that the bacterial strain of the invention have on the host immune system. Therefore, the compositions of the invention may also be useful for preventing cancer, when administered as vaccine compositions. In certain such embodiments, the bacterial strain of the invention is viable. In certain such embodiments, the bacterial strain of the invention is capable of partially or totally colonising the intestine. In certain such embodiments, the bacterial strain of the invention is viable and capable of partially or totally colonising the intestine. In other certain such embodiments, the bacterial strain of the invention may be killed, inactivated or attenuated. In certain such embodiments, the compositions may comprise a vaccine adjuvant. In certain embodiments, the compositions are for administration via injection, such as via subcutaneous injection. General

The practice of the present invention will employ, unless otherwise indicated, conventional methods of chemistry, biochemistry, molecular biology, immunology and pharmacology, within the skill of the art. Such techniques are explained fully in the literature. See, e.g., references [37] and [38-44], etc.

The term "comprising" encompasses "including" as well as "consisting" e.g. a composition "comprising" X may consist exclusively of X or may include something additional e.g. X + Y.

The term "about" in relation to a numerical value x is optional and means, for example, x+10%.

The word "substantially" does not exclude "completely" e.g. a composition which is "substantially free" from Y may be completely free from Y. Where necessary, the word "substantially" may be omitted from the definition of the invention.

References to a percentage sequence identity between two nucleotide sequences means that, when aligned, that percentage of nucleotides are the same in comparing the two sequences. This alignment and the percent homology or sequence identity can be determined using software programs known in the art, for example those described in section 7.7.18 of ref. [45]. A preferred alignment is determined by the Smith- Waterman homology search algorithm using an affine gap search with a gap open penalty of 12 and a gap extension penalty of 2, BLOSUM matrix of 62. The Smith-Waterman homology search algorithm is disclosed in ref. [46].

Unless specifically stated, a process or method comprising numerous steps may comprise additional steps at the beginning or end of the method, or may comprise additional intervening steps. Also, steps may be combined, omitted or performed in an alternative order, if appropriate.

Various embodiments of the invention are described herein. It will be appreciated that the features specified in each embodiment may be combined with other specified features, to provide further embodiments. In particular, embodiments highlighted herein as being suitable, typical or preferred may be combined with each other (except when they are mutually exclusive).

MODES FOR CARRYING OUT THE INVENTION

Example 1 - Efficacy of bacterial inocula in mouse models of cancer

Summary

This study tested the efficacy of compositions comprising bacterial strain according to the invention in a tumor model.

Materials

Test substance - Bacterial strain #MRX554.

Reference substance - Anti-CTLA-4 antibody (clone: 9H10, catalog: BE0131, isotype: Syrian Hamster IgGl, Bioxcell).

Test and reference substances vehicles - Bacterial culture medium (Yeast extract, Casitone, Fatty Acid medium (YCFA)). Each day of injection to mice, antibody was diluted with PBS (ref: BE14- 516F, Lonza, France).

Treatment doses - Bacteria: 2xl0 ⁸ in 200 YCFA. The a-CTLA-4 was injected at 10 mg/kg/inj. Anti-CTLA-4 was administered at a dose volume of 10 mL/kg/adm (i.e. for one mouse weighing 20 g, 200 of test substance will be administered) according to the most recent body weight of mice.

Routes of administration - Bacterial inoculum was administered by oral gavage (per os, PO) via a cannula. Cannulas were decontaminated every day. Anti-CTLA-4 was injected into the peritoneal cavity of mice (Intraperitoneally, IP).

Culture conditions of bacterial strain - The culture conditions for the bacterial strain were as follows:

• Pipette 10 mL of YCFA (from the prepared 10 mL E&O lab bottles) into Hungate tubes

• Seal the tubes and flush with CO2 using a syringe input and exhaust system

• Autoclave the Hungate tubes

• When cooled, inoculate the Hungate tubes with 1 mL of the glycerol stocks • Place the tubes in a static 37°C incubator for about 16 hours.

• The following day, take 1 mL of this subculture and inoculate 10 mL of YCFA (pre -warmed flushed Hungate tubes again, all in duplicate)

• Place them in a static 37°C incubator for 5 to 6h Cancer cell line and culture conditions -

The cell lines that were used are detailed in the table below:

The EMT-6 cell line was established from a transplantable murine mammary carcinoma that arose in a BALB/cCRGL mouse after implantation of a hyperplastic mammary alveolar nodule [47].

Cell culture conditions - All cell lines were grown as monolayer at 37°C in a humidified atmosphere (5% CO2, 95% air). The culture medium and supplement are indicated in the table below:

For experimental use, adherent tumor cells were detached from the culture flask by a 5 minute treatment with trypsin-versene (ref: BE17-161E, Lonza), in Hanks' medium without calcium or magnesium (ref: BE10-543F, Lonza) and neutralized by addition of complete culture medium. The cells were counted in a hemocytometer and their viability will be assessed by 0.25% trypan blue exclusion assay.

Use of animals -

Healthy female Balb/C (BALB/cByJ) mice, of matching weight and age, were obtained from CHARLES RIVER (L'Arbresles) for the EMT6 model experiments.

Animals were maintained in SPF health status according to the FELASA guidelines, and animal housing and experimental procedures according to the French and European Regulations and NRC Guide for the Care and Use of Laboratory Animals were followed [48,49]. Animals were maintained in housing rooms under controlled environmental conditions: Temperature: 22 + 2°C, Humidity 55 + 10%, Photoperiod (12h light/ 12h dark), HEPA filtered air, 15 air exchanges per hour with no recirculation. Animal enclosures were provided with sterile and adequate space with bedding material, food and water, environmental and social enrichment (group housing) as described: 900 cm ² cages (ref: green, Tecniplast) in ventilated racks, Epicea bedding (SAFE), 10 kGy Irradiated diet (A04-10, SAFE), Complete food for immuno-competent rodents - R/M-H Extrudate, water from water bottles.

Experimental design and treatments

Antitumor activity, EMT6 model

Treatment schedule - The start of first dosing was considered as DO. On DO, non-engrafted mice were randomized according to their individual body weight into groups of 9/8 using Vivo manager® software (Biosystemes, Couternon, France). On DO, the mice received vehicle (culture medium) or bacterial strain. On D14, all mice were engrafted with EMT-6 tumor cells as described below. On D24, mice from the positive control group received anti-CTLA-4 antibody treatments. The treatment schedule is summarized in the table below:

The monitoring of animals was performed as described below.

Induction of EMT6 tumors in animals - On D14, tumors were induced by subcutaneous injection of lxlO ⁶ EMT-6 cells in 200 RPMI 1640 into the right flank of mice.

Euthanasia - Each mouse was euthanized when it reached a humane endpoint as described below, or after a maximum of 6 weeks post start of dosing.

Animal monitoring

Clinical monitoring - The length and width of the tumor was measured twice a week with callipers and the volume of the tumor was estimated by this formula [50]:

_^ , width ² x length

Tumor volu me =

2

Humane endpoints [51]: Signs of pain, suffering or distress: pain posture, pain face mask, behaviour; Tumor exceeding 10% of normal body weight, but non-exceeding 2000 mm ³ ; Tumors interfering with ambulation or nutrition; Ulcerated tumor or tissue erosion; 20% body weight loss remaining for 3 consecutive days; Poor body condition, emaciation, cachexia, dehydration; Prolonged absence of voluntary responses to external stimuli; Rapid laboured breathing, anaemia, significant bleeding; Neurologic signs: circling, convulsion, paralysis; Sustained decrease in body temperature; Abdominal distension.

Anaesthesia - Isoflurane gas anesthesia were used for all procedures: surgery or tumor inoculation, i.v. injections, blood collection. Ketamine and Xylazine anesthesia were used for stereotaxia surgical procedure.

Analgesia - Carprofen or multimodal carprofen/buprenorphine analgesia protocol were adapted to the severity of surgical procedure. Non-pharmacological care was provided for all painful procedures. Additionally, pharmacological care not interfering with studies (topic treatment) were provided at the recommendation of the attending veterinarian. Euthanasia - Euthanasia of animals was performed by gas anesthesia over-dosage (Isoflurane) followed by cervical dislocation or exsanguination.

Results

Antitumor activity, EMT6 model

The results are shown in Figure 1. Treatment with the bacterial strain of the invention led to a clear reduction in tumour volume relative to both the negative controls. The positive control also led to a reduction in tumour volume, as would be expected.

These data indicate that strain MRX554 may be useful for treating or preventing cancer, and in particular for reducing tumour volume in breast cancer.

Example 2 - Stability testing

A composition described herein containing the bacterial strain described herein is stored in a sealed container at 25 ^° C or 4 ^° C and the container is placed in an atmosphere having 30%, 40%, 50%, 60%, 70%, 75%, 80%, 90% or 95% relative humidity. After 1 month, 2 months, 3 months, 6 months, 1 year, 1.5 years, 2 years, 2.5 years or 3 years, at least 50%, 60%, 70%, 80% or 90% of the bacterial strain shall remain as measured in colony forming units determined by standard protocols. Example 3 - Analysis of carbohydrate metabolism - API 50 CHL analysis of MRx0554

The Analytical Profile Index (API) test system consists of strips which contain miniaturised biochemical tests which assay for enzymatic activity in bacterial species. These tests are routinely used in the characterisation of novel strains. API 50 CHL testing was carried out to examine carbohydrate metabolism in MRx0554. As per manufacturer's instructions, bacteria were cultured in 10 ml YCFA broth for 16-18 hours at 37 °C in an anaerobic workstation. This culture was diluted in 10 ml API CHL Medium so as to achieve a density roughly equivalent to McFarland standard No. 2, and 110 μΐ of this mixture was used to inoculate each cupule on a set of API 50 CH test strips. Test strips were incubated in a humidified incubation box at 37 °C in an anaerobic workstation for 48 hours, following which the colour of each cupule was recorded and assigned a value of negative, intermediate positive, positive or doubtful.

Using API 50 CHL analysis, MRx0554 tested positive for fermentation of L-arabinose, D-ribose, D-xylose, D-galactose, D-glucose, D-fructose, D-mannose, N-acetylglucosamine, amygdalin, arbutin, esculin, salicin, D-cellobiose, D-maltose, D-saccharose (sucrose), D-trehalose, gentiobiose, D-tagatose, and potassium gluconate (Figure 2). Intermediate reactions were observed for D-mannitol, methyl a-D-glucopyranoside, D-lactose, D-raffinose, amidon (starch), and D- turanose.

SEQUENCES

SEQ ID NO:l (Enterococcus gallinarum 16S rRNA gene - AF039900)

1 taatacatgc aagtcgaacg ctttttcttt caccggagct tgctccaccg aaagaaaaag 61 agtggcgaac gggtgagtaa cacgtgggta acctgcccat cagaagggga taacacttgg 121 aaacaggtgc taataccgta taacactatt ttccgcatgg aagaaagttg aaaggcgctt 181 ttgcgtcact gatggatgga cccgcggtgc attagctagt tggtgaggta acggctcacc 241 aaggccacga tgcatagccg acctgagagg gtgatcggcc acactgggac tgagacacgg 301 cccagactcc tacgggaggc agcagtaggg aatcttcggc aatggacgaa agtctgaccg 361 agcaacgccg cgtgagtgaa gaaggttttc ggatcgtaaa actctgttgt tagagaagaa 421 caaggatgag agtagaacgt tcatcccttg acggtatcta accagaaagc cacggctaac 481 tacgtgccag cagccgcggt aatacgtagg tggcaagcgt tgtccggatt tattgggcgt 541 aaagcgagcg caggcggttt cttaagtctg atgtgaaagc ccccggctca accggggagg 601 gtcattggaa actgggagac ttgagtgcag aagaggagag tggaattcca tgtgtagcgg 661 tgaaatgcgt agatatatgg aggaacacca gtggcgaagg cggctctctg gtctgtaact 721 gacgctgagg ctcgaaagcg tggggagcga acaggattag ataccctggt agtccacgcc 781 gtaaacgatg agtgctaagt gttggagggt ttccgccctt cagtgctgca gcaaacgcat 841 taagcactcc gcctggggag tacgaccgca aggttgaaac tcaaaggaat tgacgggggc 901 ccgcacaagc ggtggagcat gtggtttaat tcgaagcaac gcgaagaacc ttaccaggtc 961 ttgacatcct ttgaccactc tagagataga gcttcccctt cgggggcaaa gtgacaggtg 1021 gtgcatggtt gtcgtcagct cgtgtcgtga gatgttgggt taagtcccgc aacgagcgca 1081 acccttattg ttagttgcca tcatttagtt gggcactcta gcgagactgc cggtgacaaa 1141 ccggaggaag gtggggatga cgtcaaatca tcatgcccct tatgacctgg gctacacacg 1201 tgctacaatg ggaagtacaa cgagttgcga agtcgcgagg ctaagctaat ctcttaaagc 1261 ttctctcagt tcggattgta ggctgcaact cgcctacatg aagccggaat cgctagtaat 1321 cgcggatcag cacgccgcgg tgaatacgtt cccgggcctt gtacacaccg cccgtcacac 1381 cacgagagtt tgtaacaccc gaagtcggtg aggtaacctt tttggagcca gccgcctaag 1441 gtgggataga tgattggggt gaagtcgtaa caaggtagcc gtatcggaag gtgcggctgg 1501 atcacc

SEQ ID NO:2 - see electronic sequence listing. Strain MRX554 genome sequence. Ns in the sequence represent gaps between contigs. SEQ ID NO:3 (16S rRNA gene for Enterococcus gallinarum strain MRX554)

1 taatacatgc aagtcgaacg ctttttcttt caccggagct tgctccaccg aaagaaaaag

61 agtggcgaac gggtgagtaa cacgtgggta acctgcccat cagaagggga taacacttgg

121 aaacaggtgc taataccgta taacactatt ttccgcatgg aagaaagttg aaaggcgctt

181 ttgcgtcact gatggatgga cccgcggtgc attagctagt tggtgaggta acggctcacc

241 aaggccacga tgcatagccg acctgagagg gtgatcggcc acactgggac tgagacacgg

301 cccagactcc tacgggaggc agcagtaggg aatcttcggc aatggacgaa agtctgaccg

361 agcaacgccg cgtgagtgaa gaaggttttc ggatcgtaaa actctgttgt tagagaagaa

421 caaggatgag agtagaacgt tcatcccttg acggtatcta accagaaagc cacggctaac

481 tacgtgccag cagccgcggt aatacgtagg tggcaagcgt tgtccggatt tattgggcgt

541 aaagcgagcg caggcggttt cttaagtctg atgtgaaagc ccccggctca accggggagg

601 gtcattggaa actgggagac ttgagtgcag aagaggagag tggaattcca tgtgtagcgg

661 tgaaatgcgt agatatatgg aggaacacca gtggcgaagg cggctctctg gtctgtaact

721 gacgctgagg ctcgaaagcg tggggagcga acaggattag ataccctggt agtccacgcc

781 gtaaacgatg agtgctaagt gttggagggt ttccgccctt cagtgctgca gcaaacgcat

841 taagcactcc gcctggggag tacgaccgca aggttgaaac tcaaaggaat tgacgggggc

901 ccgcacaagc ggtggagcat gtggtttaat tcgaagcaac gcgaagaacc ttaccaggtc

961 ttgacatcct ttgaccactc tagagataga gcttcccctt cgggggcaaa gtgacaggtg

1021 gtgcatggtt gtcgtcagct cgtgtcgtga gatgttgggt taagtcccgc aacgagcgca

1081 acccttattg ttagttgcca tcatttagtt gggcactcta gcgagactgc cggtgacaaa

1141 ccggaggaag gtggggatga cgtcaaatca tcatgcccct tatgacctgg gctacacacg

1201 tgctacaatg ggaagtacaa cgagttgcga agtcgcgagg ctaagctaat ctcttaaagc

1261 ttctctcagt tcggattgta ggctgcaact cgcctacatg aagccggaat cgctagtaat

1321 cgcggatcag cacgccgcgg tgaatacgtt cccgggcctt gtacacaccg cccgtcacac

1381 cacgagagtt tgtaacaccc gaagtcggtg aggtaacctt tttggagcca gccgcctaag

1441 gtgggataga tgattggggt gaagtcgtaa caaggtagcc gtatcggaag gtgcggctgg

1501 atcacc

REFERENCES

[I] Spor et al. (2011) Nat Rev Microbiol. 9(4):279-90.

[2] Eckburg et al. (2005) Science. 10;308(5728): 1635-8.

[3] Macpherson et al. (2001) Microbes Infect. 3(12): 1021-35

[4] Macpherson et al. (2002) Cell Mol Life Sci. 59(12):2088-96.

[5] Mazmanian et al. (2005) Cell 15;122(1): 107-18.

[6] Frank et al. (2007) PNAS 104(34): 13780-5.

[7] Scanlan et al. (2006) J Clin Microbiol. 44(11):3980-8.

[8] Kang et al. (2010) Inflamm Bowel Dis. 16(12):2034-42.

[9] Machiels et al. (2013) Gut. 63(8): 1275-83.

[10] WO 2013/050792

[I I] WO 03/046580

[12] WO 2013/008039

[13] WO 2014/167338

[14] Goldin and Gorbach (2008) Clin Infect Dis. 46 Suppl 2:S96-100.

[15] Azad et al. (2013) BMJ. 347:f6471.

[16] Strickertsson et al. (2014) Genes. 5(3): 726-738.

[17] Collins et al. (1984) Int J Syst Evol Microbiol. 34: 220-223.

[18] Masco et al. (2003) Systematic and Applied Microbiology, 26:557-563. [19] Srutkova et al. (2011) J. Microbiol. Methods, 87(l): 10-6.

[20] Haabeth et al. (2012) Oncolmmunology 1(1): 1146-1152.

[21] Lejeune et al. (2006) Cancer Immun. 6:6

[22] Pace et al. (1983) PNAS. 80:8782-6.

[23] Sgadari et al. (1996) PNAS. 93: 13791 -6.

[24] Arenberg et al. (1996) J. Exp. Med. 184:981-92.

[25] Sgadari et al. (1997) Blood. 89:2635-43.

[26] Miyamoto-Shinohara et al. (2008) J. Gen. Appl. Microbiol., 54, 9-24.

[27] Cryopreservation and Freeze-Drying Protocols, ed. by Day and McLellan, Humana Press.

[28] Leslie et al. (1995) Appl. Environ. Microbiol. 61, 3592-3597.

[29] Mitropoulou et al. (2013) J Nutr Metab. (2013) 716861.

[30] Kailasapathy et al. (2002) Curr Issues Intest Microbiol. 3(2):39-48.

[31] Handbook of Pharmaceutical Excipients, 2nd Edition, (1994), Edited by A Wade and PJ Weller

[32] Remington's Pharmaceutical Sciences, Mack Publishing Co. (A. R. Gennaro edit. 1985)

[33] US 2016/0067188

[34] Handbook of Microbiological Media, Fourth Edition (2010) Ronald Atlas, CRC Press.

[35] Maintaining Cultures for Biotechnology and Industry (1996) Jennie C. Hunter-Cevera, Academic Press

[36] Strobel (2009) Methods Mol Biol. 581 :247-61.

[37] Gennaro (2000) Remington: The Science and Practice of Pharmacy. 20th edition, ISBN: 0683306472.

[38] Molecular Biology Techniques: An Intensive Laboratory Course, (Ream et al., eds., 1998, Academic Press).

[39] Methods In Enzymology (S. Colowick and N. Kaplan, eds., Academic Press, Inc.)

[40] Handbook of Experimental Immunology, Vols. I-IV (D.M. Weir and C.C. Blackwell, eds, 1986, Blackwell Scientific Publications)

[41] Sambrook et al. (2001) Molecular Cloning: ALaboratory Manual, 3rd edition (Cold Spring Harbor Laboratory Press).

[42] Handbook of Surface and Colloidal Chemistry (Birdi, K.S. ed., CRC Press, 1997)

[43] Ausubel et al. (eds) (2002) Short protocols in molecular biology, 5th edition (Current Protocols).

[44] PCR (Introduction to Biotechniques Series), 2nd ed. (Newton & Graham eds., 1997, Springer Verlag)

[45] Current Protocols in Molecular Biology (F.M. Ausubel et al., eds., 1987) Supplement 30

[46] Smith & Waterman (1981) Adv. Appl. Math. 2: 482-489.

[47] Rockwell et al., (1972) J Natl Cancer Inst. 49:735^19.

[48] Principe d'ethique de l'experimentation animale, Directive n°2010/63 CEE 22nd September 2010, Decret n°2013-118 1st February 2013.

[49] Guide for the Care and Use of Laboratory Animals: Eighth Edition. The National Academies Press; 2011

[50] Simpson-Herren and Lloyd (1970) Cancer Chemother Rep. 54: 143-74.

[51] Workman et al. (2010) Br. J. Cancer. 102: 1555-77.