This gene encodes a cancer-testis antigen that is highly expressed in hepatocellular carcinomas and other tumors and weakly expressed in normal tissues except testis. The protein is strongly expressed in spermatogonia, primary spermatocytes, and Sertoli cells in seminiferous tubules. This protein may have a role in the control of early testicular differentiation and cell proliferation. [provided by RefSeq, Jan 2010]