Hepatocyte growth factor (HGF) receptor, also called mesenchymal–epithelial transition factor (MET or c-MET), is another receptor tyrosine kinase that has been identified as a target for therapy due to its implication in the tumorigenesis and metastasis of certain cancers, including cholangiocarcinoma [40]. The gene discussed is NTRK1; the disease is cholangiocarcinoma.