Cancer Antigen 1 (CAGE1)

CTAG3, designated CAGE1, with an expression pattern similar to that of cancer/testis antigens. The deduced 639-amino acid soluble CTAG3 protein has a calculated molecular mass of 73 kD and contains 2 consensus glycosylation sites and 10 consensus protein kinase C phosphorylation sites.

It shares 76% sequence identity with a monkey homolog. RT-PCR analysis detected testis-specific expression among normal tissues and wide expression among various cancer tissues and cancer cell lines including those from cervical, melanoma, hepatic, renal, myeloma, and breast cancers. CTAG3 was overexpressed in cancer tissues compared with surrounding noncancerous tissues. Transfection experiments with a GFP-CTAG3 construct indicated a predominantly nuclear localization.