Current status of molecularly targeted therapy for hepatocellular carcinoma: clinical practice.

In recent years, molecular-targeted agents have been used clinically to treat various malignant tumors. In May 2009, sorafenib (Nexavar) was approved in Japan for "unresectable hepatocellular carcinoma (HCC)", and was the first molecular-targeted agent for use in liver cancer. To date, sorafenib is the only molecular-targeted agent whose survival benefit has been demonstrated in two global phase III randomized controlled trials, and it has now been approved worldwide. Phase III clinical trials are now underway to compare other molecular-targeted agents with sorafenib as first-line treatment agents, and to evaluate other multi-kinase inhibitors of the vascular endothelial growth factor and platelet-derived growth factor receptors, as well as drugs targeting the epidermal growth factor receptor, insulin-like growth factor receptor, and mammalian target of rapamycin, in addition to other molecules targeting other components of the signal transduction pathways. This review outlines the main pathways involved in the development and progression of HCC and the agents that target these pathways.