This application claims priority of U.S. Provisional Patent Application No. 62/341,331 filed May 25, 2016, the entire contents of which are hereby incorporated herein by reference.

Throughout this application, various publications are referenced by author and publication date within parentheses. Full citations for these publications may be found at the end of the specification or at the end of each experimental section. The disclosures of these publications are hereby incorporated by reference into this application to describe more fully the art to which this invention pertains . This invention was made with government support under grant number 1R01 HL112626 awarded by the National Institutes of Health.

This application incorporates-by-reference nucleotide and/or amino acid sequences which are present in the file named "170525_88010-A- PCT_SequenceListing_DH.txt" which is 32.6 kilobytes in size, and was created May 24, 2017 in the IBM-PCT machine format, having an operating system compatibility with MS-Windows, which is contained in the text file filed May 25, 2017 as part of this application. BACKGROUND OF THE INVENTION

Notch proteins play key roles in developmental decisions involving the vasculature, the hematopoietic system, and the nervous system. As such, an understanding of their function is key to understanding how cell-fate decisions and commitment are controlled during development and in adult tissues. To date, several reports on Notch or Notch ligand gene disruptions have described vascular phenotypes providing emphasis that this pathway is a fundamental part of the machinery that guides vascular development. Aberrant Notch activity has been linked to human pathologies; including both cancer and vascular disorders (CADASIL) . The analysis of Notch in tumor angiogenesis has only recently begun; however, our discovery of potential downstream targets of Notch suggests a role in pathological processes associated with angiogenesis. For instance, VEGFR-3 has been linked to both tumor angiogenesis and tumor lymphangiogenesis . The expression or function of several other potential Notch targets has also been linked to tumor angiogenesis; including ephrinB2, Id3, Angiopoietin 1, and PDGF-B. Insights on the role of these targets in Notch gene function will clearly facilitate future analysis of Notch in human pathologies .

SUMMARY OF THE INVENTION

This invention provides a fusion protein, the sequence of which, commencing at the N-terminus of the fusion protein, is identical to the sequence of amino acids in:

(a) an extracellular domain of a human Notchl receptor protein, followed by

(b) an Fc portion of an antibody,

wherein the extracellular domain of the human Notchl receptor protein

(i) commences with the amino acid present at the N-terminus of EGF- like repeat 10 and

(ii) extends to and includes the C-terminal amino acid of EGF-like repeat 18.

Also provided is a fusion protein, the sequence of which, commencing at the N-terminus of the fusion protein, is identical to the sequence of amino acids in:

(a) an extracellular domain of a human Notchl receptor protein, followed by

(b) an Fc portion of an antibody,

wherein the extracellular domain of the human Notchl receptor protein

(i) commences with the amino acid present at the N-terminus of EGF- like repeat 10 and

(ii) extends to and includes the C-terminal amino acid of EGF-like repeat 20.

Also provided is a fusion protein, the sequence of which, commencing at the N-terminus of the fusion protein, is identical to the sequence of amino acids in:

(a) an extracellular domain of a human Notchl receptor protein, followed by

(b) a linker sequence, followed by

(c) an Fc portion of an antibody,

wherein the extracellular domain of the human Notchl receptor protein

(i) commences with the amino acid present at the N-terminus of EGF- like repeat 10 and

(ii) extends to and includes the C-terminal amino acid of EGF-like repeat 18. Also provided is a fusion protein, the sequence of which, commencing at the N-terminus of the fusion protein, is identical to the sequence of amino acids in:

(a) an extracellular domain of a human Notchl receptor protein, followed by

(b) a linker sequence, followed by

(c) an Fc portion of an antibody,

wherein the extracellular domain of the human Notchl receptor protein

(i) commences with the amino acid present at the N-terminus of EGF- like repeat 10 and

(ii) extends to and includes the C-terminal amino acid of EGF-like repeat 20.

Also provided is a fusion protein the sequence of which, commencing at the N-terminus of the fusion protein, is identical to the sequence of amino acids in:

(a) a signal peptide, followed by

(b) an extracellular domain of a human Notchl receptor protein, followed by

(c) an Fc portion of an antibody,

wherein the extracellular domain of the human Notchl receptor protein

(i) commences with the amino acid present at the N-terminus of EGF- like repeat 10 and

(ii) extends to and includes the C-terminal amino acid of EGF-like repeat 18.

Also provided is a fusion protein the sequence of which, commencing at the N-terminus of the fusion protein, is identical to the sequence of amino acids in:

(a) a signal peptide, followed by

(b) an extracellular domain of a human Notchl receptor protein, followed by

(c) an Fc portion of an antibody,

wherein the extracellular domain of the human Notchl receptor protein (i) commences with the amino acid present at the N-terminus of EGF- like repeat 10 and

(ii) extends to and includes the C-terminal amino acid of EGF-like repeat 20. Also provided is a composition comprising the any of the fusion proteins of this invention and a pharmaceutically acceptable carrier.

Also provided is a method of treating a subject suffering from age- related macular degeneration (AMD) which comprises administering to the subject any of the compositions of the invention in an amount effective to treat the subject's AMD.

Also provided is a method of treating a subject suffering from diabetic retinopathy which comprises administering to the subject any of the compositions of the invention in an amount effective to treat the subject's diabetic retinopathy.

Also provided is a method of treating a subject suffering from cancer which comprises administering to the subject any of the compositions of this invention in an amount effective to treat the subject's cancer.

BRIEF DESCRIPTION OF THE FIGURES

Figure 1: The amino acids sequence of the human NOTCH1 protein (SEQ ID NO: 1) . Figure 2 : The nucleic acid sequence of human Notchl decoy 10-24 is set forth in SEQ ID NO : 2. Human Notch 1 signal peptides corresponds to nucleotides 1-69 of SEQ ID NO: 2, EGF-like repeats 10-24 correspond to nucleotides 70-1788 of SEQ ID NO: 2 and Human Fc corresponds to nucleotides 1789-2502 of SEQ ID NO: 2. The amino acid sequence of human Notchl decoy 10-24 is set forth in SEQ ID NO: 3.

Figure 3 : Schematic of design of Notchl Decoys.

Figure 4: Assay demonstrating that Notchl 10-20, 10-18, and 10-16 decoys are secreted at higher levels than Notchl 1-13 and 10-24 decoys.

Figure 5 : Results of assay demonstrating that Notchl 10-20 decoy blocks Jagl-Notch and Notchl 10-18 decoy blocks both Jagl and D114- Notch.

Figure 6: Results of assay demonstrating that Notchl 10-20 decoy is secreted at higher levels than Notchl 10-24 decoy and maintains structural integrity after purification and storage. Figure 7: Schematic depiction of assay and results of assay demonstrating that purified Notchl 10-20 decoy retains functional inhibition of Jagl-Notch activation.

Figure 8: Schematic depiction of assay and results of assay demonstrating that Notchl 10-20 decoy retains functional inhibition of sprouting angiogenesis similar to Notchl 10-24 Decoy.

Figure 9: Results of assay demonstrating that Notchl 1-13, 10-24, and 10-20 decoys inhibit migration of triple negative breast cancer cells.

Figure 10: Results of assay demonstrating that Notchl 10-20 decoy inhibits transendothelial migration of tumor cells across endothelial barriers . DETAILED DESCRIPTION OF THE INVENTION

Terms

As used in this application, except as otherwise expressly provided herein, each of the following terms shall have the meaning set forth below .

"Administering" may be effected or performed using any of the methods known to one skilled in the art. The methods comprise, for example, intralesional, intramuscular, subcutaneous, intravenous, intraperitoneal, liposome-mediated, transmucosal , intestinal, topical, nasal, oral, anal, ocular or otic means of delivery.

"Affixed" shall mean attached by any means. In one embodiment, affixed means attached by a covalent bond. In another embodiment, affixed means attached non-covalently .

"Amino acid," "amino acid residue" and "residue" are used interchangeably herein to refer to an amino acid that is incorporated into a protein, polypeptide or peptide. The amino acid can be, for example, a naturally occurring amino acid or an analog of a natural amino acid that can function in a manner similar to that of the naturally occurring amino acid.

"C-terminal" and "N-terminal" amino acid, as used herein, refers to an amino acids at or in close proximity to the carboxy or amino terminal ends, respectively, of a given protein, protein domain or amino acid sequence motif such that no amino acid residue essential to the structure, function, or characterization of the protein, protein domain or amino acid sequence motif lie beyond said C-terminal amino acid or N-terminal amino acid.

"Antibody" shall include, without limitation, (a) an immunoglobulin molecule comprising two heavy chains and two light chains and which recognizes an antigen; (b) a polyclonal or monoclonal immunoglobulin molecule; and (c) a monovalent or divalent fragment thereof. Immunoglobulin molecules may derive from any of the commonly known classes, including but not limited to IgA, secretory IgA, IgG, IgE and IgM. IgG subclasses are well known to those in the art and include, but are not limited to, human IgGl, IgG2, IgG3 and IgG4. Antibodies can be both naturally occurring and non-naturally occurring. Furthermore, antibodies include chimeric antibodies, wholly synthetic antibodies, single chain antibodies, and fragments thereof. Antibodies may be human or nonhuman. Nonhuman antibodies may be humanized by recombinant methods to reduce their immunogenicity in humans. Antibody fragments include, without limitation, Fab and Fc fragments. The "Fc portion of an antibody", in one embodiment, is a crystallizable fragment obtained by papain digestion of immunoglobulin that consists of the C-terminal half of two heavy chains linked by disulfide bonds and known as the "effector region" of the immunoglobulin. In another embodiment, "Fc portion of an antibody" means all, or substantially all, of one C-terminal half of a heavy chain. "Humanized", with respect to an antibody, means an antibody wherein some, most or all of the amino acids outside the CDR region are replaced with corresponding amino acids derived from a human immunoglobulin molecule. Small additions, deletions, insertions, substitutions or modifications of amino acids are permissible as long as they do not abrogate the ability of the antibody to bind a given antigen. Suitable human immunoglobulin molecules include, without limitation, IgGl, IgG2, IgG3, IgG4, IgA and IgM molecules. Various publications describe how to make humanized antibodies, e.g., United States Patent Nos . 4,816,567, 5,225,539, 5,585,089 and 5,693,761, and PCT International Publication No. WO 90/07861.

As used herein, the term "composition", as in pharmaceutical composition, is intended to encompass a product comprising the active ingredient (s ) and the inert ingredient ( s ) that make up the carrier, as well as any product which results, directly or indirectly from combination, complexation, or aggregation of any two or more of the ingredients, or from dissociation of one or more of the ingredients, or from other types of reactions or interactions of one or more of the ingredients .

As used herein, "effective amount" refers to an amount which is capable of treating a subject having a tumor, a disease or a disorder. Accordingly, the effective amount will vary with the subject being treated, as well as the condition to be treated. A person of ordinary skill in the art can perform routine titration experiments to determine such sufficient amount. The effective amount of a compound will vary depending on the subject and upon the particular route of administration used. Based upon the compound, the amount can be delivered continuously, such as by continuous pump, or at periodic intervals (for example, on one or more separate occasions) . Desired time intervals of multiple amounts of a particular compound can be determined without undue experimentation by one skilled in the art. In one embodiment, the effective amount is between about ^g/kg - 10 mg/kg. In another embodiment, the effective amount is between about 10μg/kg - 1 mg/kg. In a further embodiment, the effective amount is 100μg/kg. "Extracellular domain" as used in connection with Notch receptor protein means all or a portion of Notch which (i) exists extracellularly (i.e. exists neither as a transmembrane portion or an intracellular portion) and (ii) binds to extracellular ligands to which intact Notch receptor protein binds. The extracellular domain of Notch may optionally include a signal peptide ("sp") . "Extracellular domain", "ECD" and "Ectodomain" are synonymous.

"Inhibiting" the onset of a disorder or undesirable biological process shall mean either lessening the likelihood of the disorder's or process' onset, or preventing the onset of the disorder or process entirely. In the preferred embodiment, inhibiting the onset of a disorder or process means preventing its onset entirely.

"Notch", "Notch protein", and "Notch receptor protein" are synonymous. In addition, the terms "Notch-based fusion protein" and "Notch decoy" are synonymous. The following Notch amino acid sequences are known and hereby incorporated by reference: Notchl (Genbank accession no. S18188 (rat)); Notch2 (Genbank accession no. NP_077334 (rat)); Notch3 (Genbank accession no. Q61982 (mouse)); and Notch4 (Genbank accession no. T09059 (mouse)) . The following Notch nucleic acid sequences are known and hereby incorporated by reference: Notchl (Genbank accession no. XM_342392 (rat) and NM_017617 (human)); Notch2 (Genbank accession no. NM 024358 (rat), M99437 (human and AF308601 (human)); Notch3 (Genbank accession no. NM_008716 (mouse) and XM_009303 (human)); and Notch4 (Genbank accession no. NM_010929 (mouse) and NM_004557 (human) ) . The terms "nucleic acid", "polynucleotide" and "nucleic acid sequence" are used interchangeably herein, and each refers to a polymer of deoxyribonucleotides and/or ribonucleotides. The deoxyribonucleotides and ribonucleotides can be naturally occurring or synthetic analogues thereof. "Nucleic acid" shall mean any nucleic acid, including, without limitation, DNA, RNA and hybrids thereof. The nucleic acid bases that form nucleic acid molecules can be the bases A, C, G, T and U, as well as derivatives thereof. Derivatives of these bases are well known in the art, and are exemplified in PCR Systems, Reagents and Consumables (Perkin Elmer Catalogue 1996-1997, Roche Molecular Systems, Inc., Branchburg, New Jersey, USA) . Nucleic acids include, without limitation, anti-sense molecules and catalytic nucleic acid molecules such as ribozymes and DNAzymes. Nucleic acids also include nucleic acids coding for peptide analogs, fragments or derivatives which differ from the naturally-occurring forms in terms of the identity of one or more amino acid residues (deletion analogs containing less than all of the specified residues; substitution analogs wherein one or more residues are replaced by one or more residues; and addition analogs, wherein one or more resides are added to a terminal or medial portion of the peptide) which share some or all of the properties of the naturally-occurring forms.

The terms "polypeptide," "peptide" and "protein" are used interchangeably herein, and each means a polymer of amino acid residues. The amino acid residues can be naturally occurring or chemical analogues thereof. Polypeptides, peptides and proteins can also include modifications such as glycosylation, lipid attachment, sulfation, hydroxylation, and ADP-ribosylation .

As used herein, "pharmaceutically acceptable carrier" means that the carrier is compatible with the other ingredients of the formulation and is not deleterious to the recipient thereof, and encompasses any of the standard pharmaceutically accepted carriers. Such carriers include, for example, 0.01-0.1 M and preferably 0.05 M phosphate buffer or 0.8% saline. Additionally, such pharmaceutically acceptable carriers can be aqueous or non-aqueous solutions, suspensions, and emulsions. Examples of non-aqueous solvents are propylene glycol, polyethylene glycol, vegetable oils such as olive oil, and injectable organic esters such as ethyl oleate. Aqueous carriers include water, alcoholic/aqueous solutions, emulsions and suspensions, including saline and buffered media. Parenteral vehicles include sodium chloride solution, Ringer's dextrose, dextrose and sodium chloride, lactated Ringer's and fixed oils. Intravenous vehicles include fluid and nutrient replenishers , electrolyte replenishers such as those based on Ringer's dextrose, and the like. Preservatives and other additives may also be present, such as, for example, antimicrobials, antioxidants, chelating agents, inert gases, and the like. "Subject" shall mean any organism including, without limitation, a mammal such as a mouse, a rat, a dog, a guinea pig, a ferret, a rabbit and a primate. In one embodiment, the subject is a human.

"Treating" means either slowing, stopping or reversing the progression of a disease or disorder. As used herein, "treating" also means the amelioration of symptoms associated with the disease or disorder. Diseases include, but are not limited to, Tumor Angiogenesis , Atherosclerosis, Wound Healing, Retinopathy of Prematurity, Preeclampsia, Diabetic retinopathy, Ischemia, Stroke, Cardiovascular Disease, Psoriasis, lymphedema, tumorigenesis and tumor lymphangiogenesis , age-related macular degeneration (AMD), wet AMD, pancreatic cancer and breast cancer.

Angiogenesis is encountered during wound healing processes, the female menstrual cycle and endometrial remodeling, as well as during embryonic development and organ growth. In the pathological setting, angiogenesis plays an important role in different diseases like rheumatoid arthritis, psoriasis, macular degeneration, diabetic retinopathy, and tumor growth.

There has been considerable evidence in vivo, including clinical observations, that abnormal angiogenesis is implicated in a number of disease conditions, which include rheumatoid arthritis, inflammation, cancer, psoriasis, degenerative eye conditions and others.

Other diseases for use of Notch fusion proteins are metabolic disorders such as, but not limited to, Diabetes, Obesity, Prediabetic state, Atherosclerosis, Ischemia, Stroke, Cardiovascular Disease, Regulating expression of Insulin, and Regulating the function of Insulin .

The use of Notch fusion proteins is also indicated for Metabolic Syndrome refers to a combination of medical disorders that increases the risk to a person for cardiovascular disease and diabetes. Other known names referring to such syndrome is syndrome X, insulin resistance syndrome, Reaven's syndrome. Several features of the syndromes include: fasting hyperglycemia, high blood pressure, central obesity (also known as visceral obesity) , decreased High Density Lipoprotein (LDL) , elevated triglycerides, elevated uric acid levels. Fasting hyperglycemia, listed above, includes diabetes mellitus type 2 or impaired fasting glucose and impaired glucose tolerance or insulin resistance. In addition to metabolic syndrome, the Notch decoy may have indications for pre-diabetic states.

Units, prefixes and symbols may be denoted in their SI accepted form. Unless otherwise indicated, nucleic acid sequences are written left to right in 5' to 3 ' orientation and amino acid sequences are written left to right in amino- to carboxy-terminal orientation. Amino acids may be referred to herein by either their commonly known three letter symbols or by the one-letter symbols recommended by the IUPAC-IUB Biochemical Nomenclature Commission. Nucleotides, likewise, may be referred to by their commonly accepted single-letter codes.

The following abbreviations are used herein: ECD: extracellular domain; IC: intracellular domain; NECD/Fc: Notch-based fusion protein; Nl: Notchl; N2 : Notch2 ; N3 : Notch3; N4 : Notch4; Dll: Delta-like; DLL1: Delta-like 1; DLL4: Delta-like 4; JAG: JAGGED; JG: JAGGED; JAGGED-1 : JAGGED 1; JG1 : JAGGED 1; EC: endothelial cells; HUVEC: human umbilical vein endothelial cell; m.o.i.: multiplicity of infection; VEGF: vascular endothelial cell growth factor; VEGFR: vascular endothelial cell growth factor receptor; sp: signal peptide; PDGF: platelet derived growth factor; PDGFR: platelet derived growth factor receptor; P1GF: placental growth factor.

Embodiments of the Invention

This invention provides a fusion protein, the sequence of which, commencing at the N-terminus of the fusion protein, is identical to the sequence of amino acids in:

(a) an extracellular domain of a human Notchl receptor protein, followed by

(b) an Fc portion of an antibody,

wherein the extracellular domain of the human Notchl receptor protein

(i) commences with the amino acid present at the N-terminus of EGF- like repeat 10 and

(ii) extends to and includes the C-terminal amino acid of EGF-like repeat 18.

Also provided is a fusion protein, the sequence of which, commencing at the N-terminus of the fusion protein, is identical to the sequence of amino acids in:

(a) an extracellular domain of a human Notchl receptor protein, followed by

(b) an Fc portion of an antibody,

wherein the extracellular domain of the human Notchl receptor protein

(i) commences with the amino acid present at the N-terminus of EGF- like repeat 10 and

(ii) extends to and includes the C-terminal amino acid of EGF-like repeat 20.

Also provided is a fusion protein, the sequence of which, commencing at the N-terminus of the fusion protein, is identical to the sequence of amino acids in:

(a) an extracellular domain of a human Notchl receptor protein, followed by

(b) a linker sequence, followed by

(c) an Fc portion of an antibody,

wherein the extracellular domain of the human Notchl receptor protein (i) commences with the amino acid present at the N-terminus of EGF- like repeat 10 and (ii) extends to and includes the C-terminal amino acid of EGF-like repeat 18.

Also provided is a fusion protein, the sequence of which, commencing at the N-terminus of the fusion protein, is identical to the sequence of amino acids in:

(a) an extracellular domain of a human Notchl receptor protein, followed by

(b) a linker sequence, followed by

(c) an Fc portion of an antibody,

wherein the extracellular domain of the human Notchl receptor protein

(i) commences with the amino acid present at the N-terminus of EGF- like repeat 10 and

(ii) extends to and includes the C-terminal amino acid of EGF-like repeat 20.

Also provided is a fusion protein the sequence of which, commencing at the N-terminus of the fusion protein, is identical to the sequence of amino acids in:

(a) a signal peptide, followed by

(b) an extracellular domain of a human Notchl receptor protein, followed by

(c) an Fc portion of an antibody,

wherein the extracellular domain of the human Notchl receptor protein (i) commences with the amino acid present at the N-terminus of EGF- like repeat 10 and

(ii) extends to and includes the C-terminal amino acid of EGF-like repeat 18. Also provided is a fusion protein the sequence of which, commencing at the N-terminus of the fusion protein, is identical to the sequence of amino acids in:

(a) a signal peptide, followed by

(b) an extracellular domain of a human Notchl receptor protein, followed by

(c) an Fc portion of an antibody,

wherein the extracellular domain of the human Notchl receptor protein (i) commences with the amino acid present at the N-terminus of EGF- like repeat 10 and

(ii) extends to and includes the C-terminal amino acid of EGF-like repeat 20.

In an embodiment of the fusion proteins of this invention, the signal peptide is the signal peptide of human Notchl protein or the signal peptide of an IgG heavy chain.

In one embodiment of the fusion proteins of this invention, the Fc portion of the antibody is the Fc portion of a human antibody.

Also provided is a composition comprising any of the fusion proteins of this invention and a pharmaceutically acceptable carrier.

In one embodiment of the composition of this invention, the fusion protein is present in an amount effective to inhibit Jagged-Notch signaling .

In one embodiment of the composition of this invention, the fusion protein is present in an amount effective to inhibit Delta-like-Notch signaling .

Also provided is a method of treating a subject suffering from age- related macular degeneration (AMD) which comprises administering to the subject any of the compositions of the invention in an amount effective to treat the subject's AMD.

In one embodiment the AMD is wet AMD. In another embodiment the AMD is dry AMD.

Also provided is a method of treating a subject suffering from diabetic retinopathy which comprises administering to the subject any of the compositions of the invention in an amount effective to treat the subject's diabetic retinopathy.

In one embodiment of any of the methods of this invention, the method further comprises administering an inhibitor of Vascular Endothelial Growth Factor (VEGF) . In one embodiment, the inhibitor of VEGF is an inhibitor of VEGF-A, PGIF, VEGF-B, VEGF-C, or VEGF-D.

In one embodiment of any of the methods of this invention, the method further comprises administering a VEGF receptor inhibitor. In one embodiment, the VEGF receptor inhibitor is a VEGFR-1 or a VEGFR-2 inhibitor .

Also provided is a method of treating a subject suffering from cancer which comprises administering to the subject any of the compositions of this invention in an amount effective to treat the subject's cancer. In one embodiment the cancer is pancreatic cancer. In another embodiment the cancer is breast cancer.

Also provided is a method of inhibiting angiogenesis or metastasis in a tumor in a subject, the method comprising administering to the subject any of the compositions of this invention in an amount effective to reduce angiogenesis or metastasis in the tumor.

Also provided is a method of inhibiting Jagl-specific Notch activation, the method comprising administering a composition of this invention comprising, the composition comprising a fusion protein of this invention wherein the extracellular domain of the human Notchl receptor protein commences with the amino acid present at the N- terminus of EGF-like repeat 10 and extends to and includes the C- terminal amino acid of EGF-like repeat 20. In an embodiment the method does not inhibit D114-specific Notch activation. In an embodiment, the method inhibits angiogenic sprouting, cancer cell migration, and/or transendothelial migration of cancer cells across endothelial barriers .

Also provided is a method of inhibiting Jagl and D114 Notch activation, the method comprising administering a composition of this invention comprising, the composition comprising a fusion protein of this invention wherein the extracellular domain of the human Notchl receptor protein commences with the amino acid present at the N- terminus of EGF-like repeat 10 and extends to and includes the C- terminal amino acid of EGF-like repeat 18. Each embodiment disclosed herein is contemplated as being applicable to each of the other disclosed embodiments. Thus, all combinations of the various elements described herein are within the scope of the invention .

EXAMPLES

Design of Notchl Decoys

All decoys contain a designated number of EGF-like repeats from the extracellular domain of Notchl fused at the C-terminus with human IgGl Fc separated by a linker sequence. EGF-like repeats are designated in parentheses. Previous iterations of the decoys included Notchl 1-36, Notchl 1-13, and Notchl 10-24. Due to difficulty in producing relevant amounts of purified recombinant protein, inventors tested whether different variants of the decoys would be more easily secretable and examined ligand specificity with regards to inhibition of Notch activation. Using overlap extension PCR cloning, inventors were able to clone new variants including Notchl 10-22, Notchl 10-20, Notchl 10-18, and Notchl 10-16. See Figure 3. Notchl decoy secretory profile shows newer decoys are produced at higher levels than previous decoys.

Specific sequences coding for the cDNA of each decoy were cloned into a lentiviral expression construct, which was used to create Chinese hamster ovary (CHO) cells stably expressing each decoy. CHO cells are the gold standard for recombinant biotherapeutic production. Conditioned media was collected from each CHO variant after 48 hours post-infection and equivalent volumes were evaluated by western blot analysis for visual, semi-quantitative determination of relative production. As expected, the Fc-only control is produced at the highest level. From our previous work, we observed that Notchl 1-13 is produced at higher amounts than Notchl 10-24. However, both are secreted at significantly lower amounts than Fc, and Notchl 10-24 is particularly difficult to produce. Notchl 10-24Fc(rl) represents a religated Notchl 10-24 as a control product of the cloning process. Notchl 10-22 appears to be secreted at a similar level as Notchl 10- 24. However, Notchl 10-20 is secreted at even higher levels as Notchl 1-13 and Notchl 10-18 and Notchl 10-16 exhibit further enhanced secretion, providing three new potential decoys that are secreted at markedly higher levels than the previous decoys. See Figure 4.

Ligand Specificity of lentivirally-expressed Notchl Decoys.

HeLa cells transfected with a Notch classical reporter construct to examine Notch activation were co-cultured with HeLa cells expressing a vehicle control (GFP-expressing construct) , JAG1 overexpression construct, or a DLL4 overexpression construct. In addition, ligand- expressing HeLa cells were also infected to express Notchl decoys or Fc control. As illustrated in Figure 5, JAG1 and DLL4 both activate Notch. Notchl 10-24 and Notchl 1-13 inhibit JAG1 and DLL4-specific Notch activation, respectively, as previously observed. Notchl 10-22 does not inhibit JAGl-specific Notch activity, but does appear to reduce DLL4-specific Notch activity. Notchl 10-20 inhibits JAG1- specific Notch activity, but does not inhibit DLL4-specific Notch activity. Notchl 10-18 inhibits both JAG1 and DLL4-specific Notch activation, suggesting it may be a pan-Notch ligand inhibitor. Notchl 10-16 does not appear to inhibit either JAG1 or DLL4-specific Notch activation. These results show that of the newer decoys that are secreted at much higher levels than the previous decoys, Notchl 10-20 decoy retains Jagged specificity.

JAGl-specific Notchl 10-20 decoy is produced and secreted at significantly higher levels and maintains structural integrity after purification .

Decoy-expressing suspension CHO cells were cultured in shaking flask bioreactors in animal-component free media and media were collected and protein produced was purified by affinity chromatography using protein A containing chromatography columns. After purification, protein was stored in phosphate buffered saline, frozen at -80C, thawed and was analyzed by western blot analysis. Notchl 10-20 decoy is clearly produced at least two to three times more than Notchl 10- 24 decoy without appreciable breakdown of the protein. Spectrophotometric analysis confirmed a 4-fold increase in production of Notchl 10-20 over Notchl 10-24, further confirming the potential of Notchl 10-20 as a Jag-specific decoy that can be produced at relevant levels and maintain structural integrity. See Figure 6.

Purified Notchl 10-20 decoy inhibits Jagl-specific activation of Notch in a Jagl-tethered plate assay.

Jagl protein adhered to cell culture plates along with fibronectin to promote cell attachment stimulated Notch activation of a classical Notch reporter in a dual luciferase reporter assay as measured after 24hr of exposure of MDA-MB-231 triple negative breast cancer cells to Jagl. This Jagl-specific activation of Notch in the breast cancer cells was inhibited by 5ug/mL of Notchl 10-20 purified decoy indicating that the purified decoy maintains inhibitory activity after purification and this can be easily evaluated in an in vitro test of activity using a tethered ligand approach. See Figure 7.

Production/Secretion/Purification of New Decoys

Previously, Notchl 1-13, 1-24, and 10-24 decoys were difficult to produce and purify.

Cloning of novel decoys, Notchl 10-20 and 10-18 decoys has provided decoys that are much more highly produced/secreted and are able to be purified while retaining functional inhibition of ligand-specific Notch. Notchl 10-20 decoy inhibits Jagl-specific Notch activation and Notchl 10-18 inhibits both D114 and Jagl-specific Notch.

Functional Use of New Decoys

Notchl 1-13 decoy promotes angiogenic hypersprouting but leads to dysfunctional vasculature and reduced perfusion in tumors, while Notchl 1-24 and 10-24 decoys inhibit angiogenic sprouting and tumor perfusion .

The following sections of this example illustrate the anti-angiogenic activity and potential anti-metastatic activity of Notchl 10-20 decoy, initially performed by overexpressing decoy in endothelial or tumor cells .

The following data will be repeated with purified protein. Lentivirally expressed Notchl 10-20 decoy inhibits angiogenesis more robustly than Notchl 10-24 decoy.

As previously shown in PCT International Application Publication No. WO/2013/052607, D114-specific inhibition by Notchl 1-13 stimulates angiogenic hypersprouting in an in vitro fibrin bead angiogenesis assay, while inhibition of Jagl by Notchl 10-24 leads to reduced sprouting angiogenesis. While Notchl 10-20 decoy is also Jagl specific, it also inhibits angiogenesis, and in comparison to Notchl 10-24, Notchl 10-20 inhibited angiogenesis more robustly, most likely due to its greater secretion. See Figure 8.

Notchl decoys reduce migration of breast cancer cells in an assay that evaluates metastatic potential.

Notch inhibition by Notchl 1-13, Notchl 10-24, and Notchl 10-20 decoys delays lateral migration of MDA-MB-231 triple negative breast cancer cells in a wound closure assay. See Figure 9.

Lentivirally expressed Notchl 10-20 decoy inhibits migration of tumor cells across endothelial barriers indicating its potential as an anti- metastatic Jagged-specific Notch inhibitory therapeutic.

Non-specific Notch inhibition by the gamma secretase inhibitor DAPT and D114-specific inhibition by Notchl 1-13 decoy reduced transendothelial migration of MDA-MB-231 breast cancer cells across endothelial barriers, while Notchl 10-24 and Notchl 10-20 decoys robustly inhibited transendothelial migration. See Figure 10.

DISCUSSION

PCT International Application Publication No. WO/2013/052607, the contents of which are incorporated by reference, showed that D114- specific inhibition by Notchl 1-13 stimulates angiogenic hypersprouting in an in vitro fibrin bead angiogenesis assay, while inhibition of Jagl by Notchl 10-24 leads to reduced sprouting angiogenesis. However, these previous decoys had the following limitations:

1. Decoys produced/secreted at low levels, suggesting manufacturing concerns for therapeutic production.

2. Due to difficulty in producing/secreting purified protein, functionality of purified decoys could not be thoroughly evaluated.

The objective of the new decoys was to achieve high production/secretion of decoys while maintaining ligand-specificity, and achieve functionality against angiogenesis, tumor growth, and other aspects of tumor progression such as metastasis.

What inventors have achieved with new decoys: Notchl 10-20 and Notchl 10-18 Decoys

1. Smaller decoys

2. Significantly greater production/secretion

3. Maintained ligand-specificity

4. Notchl 10-20 decoy is Jagged-specific, is produced/secreted at significantly higher levels than Notchl 10-24 decoy, inhibits in vitro angiogenic sprouting, inhibits cancer cell migration, and inhibits transendothelial migration of cancer cells across endothelial barriers.

5. Notchl 10-18 decoy appears to be a pan-ligand inhibitor. We must still evaluate its physiological function.

One major difference between the decoys of this invention and previous Notch inhibitors is that these decoys will specifically target Jagged- Notch or Dll-Notch signaling. Based on preliminary work targeting Jagged-Notch or Dll-Notch signaling, when used as therapeutics, these decoys will exhibit little to no toxic effects, which are seen with other Notch inhibitors . A major improvement of the decoys of this invention is the fact that the general smaller size is designed to maximize potential to secrete and purify these decoys while still retaining the Notch ligand inhibitory properties. Thus they are a significant improvement on previously evaluated decoys, such as decoys comprising EGF-like repeats 10-24, 1-13 or 1-24.