Gene Signatures in CRC and Liver Metastasis

ABSTRACT Colorectal cancer (CRC) is one of the most common causes of cancer-related death with a worldwide incidence of almost a million cases annually in both males and females. The accelerated decrease in CRC incidence rates from 1998 to 2006 largely reflects the advances in diagnosis and treatment that have enabled to detect and remove precancerous polyps. However, the screening technology has not resulted in major improvements in the prognosis of patients with advanced cancer and the liver metastasis remains the major cause of death in CRC. About 25% of patients have detectable liver metastasis at diagnosis, that are classified as “synchronous” lesions and approximately 70% of patients develop a liver recurrence during the course of their disease, identified as “metachronous” lesions. Despite the development of different treatment modalities, the outcome for patients with unresectable metastatic lesion is still unfavorable and the metastatic spread to the liver is the major contributor to mortality in CRC. Therefore, elucidation of the molecular mechanism involved in the development of metastases, by the identification of a specific gene signature for liver metastasis in CRC, could allow prediction of the onset of metastatic disease in patients with localized tumors. This could then lead to the design of new strategies for the diagnosis and treatment of CRC.