GTP-binding protein useful in treatment and detection of cancer

A pharmaceutical composition comprising a substance that modulates the status of a cell that expresses 103P3E8.

A method of generating a mammalian immune response directed to 103P3E8, the method comprising:

• exposing the mammal's immune system to an immunogenic portion of an 103P3E8-related protein or a nucleotide sequence that encodes said protein, whereby an immune response is generated to 103P3E8.

A method of delivering a cytotoxic agent to a cell that expresses 103P3E8, said method comprising:

• conjugating the cytotoxic agent to an antibody or fragment thereof that specifically binds to a 103P3E8 epitope;
• and,
• exposing the cell to the antibody-agent conjugate.

A method of inducing an immune response to a 103P3E8 protein, said method comprising:

• providing a 103P3E8-related protein that comprises at least one T cell or at least one B cell epitope;
• contacting the epitope with an immune system T cell or B cell respectively, whereby the immune system T cell or B cell is induced.

An antibody or fragment thereof that specifically binds to a 103P3E8-related protein.

An assay for detecting the presence of a 103P3E8-related protein or polynucleotide in a biological sample from a patient who has or who is suspected of having cancer, comprising steps of:

• contacting the sample with an antibody or another polynucleotide, respectively, that specifically binds to the 103P3E8-related protein or polynucleotide, respectively;
• and,
• detecting the binding of 103P3E8-related protein or polynucleotide, respectively, in the sample thereto.

An assay for detecting the presence of 103P3E8 mRNA in a biological sample from a patient who has or who is suspected of having cancer, said method comprising:

• (a) producing cDNA from the sample by reverse transcription using at least one primer;
• (b) amplifying the cDNA so produced using 103P3E8 polynucleotides as sense and antisense primers to amplify 103P3E8 cDNAs therein, wherein the 103P3E8 polynucleotides used as the sense and antisense probes are capable of amplifying the 103P3E8 cDNA contained within the plasmid as deposited with American Type Culture Collection as Accession No. PTA-1262;
• (c) detecting the presence of the amplified 103P3E8 cDNA.