Tumor marker, and method for collecting and detecting tumor cell in distinction from contaminant cell

A method of detecting a tumor cell contained in a sample in distinction from a contaminant cell, the method comprising detecting a gene encoding any of the following polypeptides (i) to (iii) present in the sample:

• (i) a polypeptide comprising at least the amino acid sequence of any of SEQ ID NOs:
• 1 to 3;
• (ii) a polypeptide comprising an amino acid sequence having a homology of not less than 85% to the amino acid sequence of any of SEQ ID NOs:
• 1 to 3;
• and
• (iii) a polypeptide comprising at least a splicing variant of the amino acid sequence of any of SEQ ID NOs:
• 1 to 3, or a polypeptide comprising at least a splicing variant of a polypeptide having a homology of not less than 85% to the amino acid sequence of any of SEQ ID NOs:
• 1 to 3, and
• wherein the tumor cell is an EpCAM (Epithelial Cell Adhesion Molecule)-negative tumor cell.

A method of collecting a tumor cell, the method comprising:

• detecting a tumor cell contained in a sample in distinction from contaminant cell;
• and collecting the detected tumor cell using collection means;
• wherein the detection of the tumor cell is carried out by detecting one or more polypeptides selected from the group consisting of the following (i) to (iii) present in the sample:
• (i) a polypeptide comprising at least the amino acid sequence of any of SEQ ID NOs:
• 1 to 3;
• (ii) a polypeptide comprising at least an amino acid sequence having a homology of not less than 85% to the amino acid sequence of any of SEQ ID NOs:
• 1 to 3;
• and
• (iii) a polypeptide comprising at least a splicing variant of the amino acid sequence of any of SEQ ID NOs:
• 1 to 3, or a polypeptide comprising at least a splicing variant of a polypeptide having a homology of not less than 85% to the amino acid sequence of any of SEQ ID NOs:
• 1 to 3, and
• wherein the tumor cell is an EpCAM (Epithelial Cell Adhesion Molecule)-negative tumor cell.