Pharmacogenetics of hepatocellular carcinoma and cholangiocarcinoma.

Primary liver cancers constitute the fourth most deadly group of cancers. Their poor prognosis is due in part to the pre-existence and/or development, often during treatment, of powerful mechanisms accounting for the poor response of cancer cells to antitumor drugs. These include both impaired gene expression and the appearance of spliced variants, polymorphisms and mutations, affecting the function of genes leading to the reduction in intracellular concentrations of active agents, changes in molecular targets and survival pathways, altered tumor microenvironment and phenotypic transition. The present review summarizes available information regarding the role of germline and somatic mutations affecting drug transporters, enzymes involved in drug metabolism, organelles and signaling molecules related to liver cancer chemoresistance. A more complete picture of the actual complexity of this problem is urgently needed for carrying out further pharmacogenomic studies aimed to improve the management of patients suffering from hepatocellular carcinoma or cholangiocarcinoma.