Induction of apoptosis and cell growth inhibition by protein 4.33

An isolated P4.33 protein or polypeptide expressed by the DNA sequence of SEQ ID NO:1, or expressed by a sequence having at least 90% homology with the coding region of SEQ ID NO:1.

A transfected cell comprising an expression vector having a DNA sequence that codes on expression for a P4.33 protein or polypeptide taken from the sequence of SEQ ID NO:2, or for a fusion protein comprising the P4.33 protein or polypeptide operatively associated with a heterologous polypeptide.

The method according to claim 0.5 wherein the P4.33 protein is present on a cell membrane or fragment thereof.

A method for identifying test compounds having therapeutic activity, comprising:

• (a) contacting a test compound with a cell expressing a functional P4.33 protein or peptide;
• and
• (b) determining whether the test compound binds to the P4.33 protein or peptide, whereby test compounds that bind to the P4.33 protein or peptide are identified as therapeutic compounds.

A method for identifying test compounds having therapeutic activity, comprising:

• (a) contacting a test compound, in the presence of a functional IGFBP-3 protein, with a cell expressing a functional P4.33 protein;
• and
• (b) determining whether the test compound inhibits binding of the IGFBP-3 protein to the P4.33 protein, whereby test compounds that inhibit binding of the IGFBP-3 protein to the P4.33 protein are identified as therapeutic compounds.

A method for identifying test compounds having therapeutic activity, comprising:

• (a) contacting a test compound with a cell expressing, or a cell lysate containing P4.33 mRNA sequences;
• and
• (b) determining whether the test compound modulates transcription or translation of P4.33 mRNA sequences, whereby test compounds that modulate transcription or translation of the P4.33 mRNA sequences are identified as therapeutic compounds.

A method for treating or preventing cancer in a patient needing treatment, comprising administering to the patient in which such treatment or prevention is desired a therapeutically effective amount of an anti-P4.33 antibody that binds to the extracellular domain of P4.33.

A method for treating or preventing cancer in a patient needing treatment comprising administering to the patient in which such treatment or prevention is desired a therapeutically effective amount of a P4.33 antisense molecule, or ribozyme molecule.

An antibody specific for a P4.33 protein or peptide of SEQ ID NO:2, or for a fusion protein thereof.

An anticancer pharmaceutical composition comprising an antibody, or a binding fragment thereof, that binds to a P4.33 protein or peptide of SEQ ID NO:2, and a pharmaceutically acceptable carrier.

A method for targeting a therapeutic agent to solid tumor tissue, wherein the solid tumor tissue is characterized by expression of P4.33, comprising attaching the therapeutic agent to an isolated polypeptide, wherein the polypeptide binds to the extracellular domain of P4.33 at an affinity of at least 108.

An assay for cancer treatment, prognosis or diagnosis in a patient for cancer cells that express P4.33 protein or peptides, comprising:

• (a) obtaining a bodily fluid sample from a patient;
• and
• (b) determining the amount of P4.33 protein or peptides expressed using an anti-P4.33 antibody-based assay, whereby the cancer treatment, prognosis or diagnosis is made.

An assay for cancer treatment, prognosis or diagnosis in a patient for cancer cells that express P4.33-specific sequences, comprising:

• (a) obtaining a bodily fluid sample from a patient;
• and
• (b) performing a sequence identity assay to detect P4.33-specific sequences.

An antagonist of P4.33 biological activity, wherein the antagonist is a P4.33-specific antisense molecule, or a P4.33-specific ribozyme molecule.

An anticancer pharmaceutical composition comprising a therapeutically effective amount of a P4.33 antagonist, and a pharmaceutically acceptable carrier, wherein the P4.33 antagonist is a P4.33-specific antisense molecule, or a P4.33-specific ribozyme molecule.

An anticancer pharmaceutical composition comprising a therapeutically effective amount of a P4.33 protein or polypeptide of SEQ ID NO:2, and a pharmaceutically acceptable carrier.

An modulator of P4.33 biological activity, wherein the modulator is a polypeptide fragment comprising amino acids 88-264 of IGFBP-3.