Small molecule c-Met kinase inhibitors: a review of recent patents.

IMPORTANCE OF THE FIELD: c-Met kinase is the receptor for hepatocyte growth factor. Primarily expressed on epithelial and mesenchymal cells its normal function is associated with wound healing, liver regeneration and embryo development. However, dysregulation of c-Met through overexpression, gene amplification, mutation or a ligand-dependent autocrine/paracrine loop is associated with tumorigenesis. c-Met dysregulation in human cancer patients is typically associated with a poor prognosis, aggressive disease, increased metastasis and shortened patient survival. Targeting the hepatocyte growth factor/c-Met signalling pathway as a means of cancer therapy has, therefore, become increasingly popular with a number of different therapeutic approaches undergoing clinical trials. AREAS COVERED BY THIS REVIEW: This review covers the patent applications for small molecule c-Met kinase inhibitors since 2007, attempts to place them in context from a structural point of view and examines their potential applications in cancer therapy. WHAT THE READER WILL GAIN: Readers will gain an overview of the structural types of c-Met inhibitors, the major players in the field and an insight into what is progressing into the clinic. TAKE HOME MESSAGE: This area is developing rapidly and the results of the various ongoing clinical trials will generate an increased understanding of the potential benefits and pitfalls of c-Met inhibitors as therapeutic agents.