Identification and characterization of CRG-L2, a new marker for liver tumor development.

Liver cancer is very common worldwide and the rates of hepatocellular carcinoma (HCC) have increased by over 70% in the last 2 decades in the US. Late diagnosis, because of the lack of clinical symptoms, and decreased hepatic function, because of underlying hepatic disease, lead to the extremely high mortality rates associated with HCC. Clearly, the identification of markers that are expressed early in the development of HCC and that are easily detected in high-risk patients would aid in early diagnosis and increased survival. We present the cloning and characterization of a novel gene, CRG-L2 (Cancer related gene-Liver 2), which displays high expression in murine and human hepatocellular carcinomas. Using in situ hybridization, we show that CRG-L2 mRNA levels are increased early during the development of liver tumors in C3H/HeJ mice, and that in normal tissues CRG-L2 mRNA is restricted to the murine testis and human placenta. Its restricted expression in normal tissues and unique early upregulation during tumor development make CRG-L2 an excellent candidate as a new clinical marker of HCC.