MET in Lung Cancer: Biomarker Selection Based on Scientific Rationale

MET or hepatocyte growth factor (HGF) receptor pathway signaling mediates wound healing and hepatic regeneration, with pivotal roles in embryonic, neuronal, and muscle development. However, dysregulation of MET signaling mediates proliferation, apoptosis, and migration and is implicated in a number of malignancies. In non-small cell lung cancer (NSCLC), aberrant MET signaling can occur through a number of mechanisms that collectively represent a significant proportion of patients. These include MET or HGF protein overexpression, gene amplification, gene mutation or fusion/rearrangement, or aberrations in downstream signaling or regulatory components. Responses to MET tyrosine kinase inhibitors have been documented in clinical trials in patients with -amplified or MET-overexpressing NSCLC, and case studies or case series have shown that mutation/deletion is a biomarker that is also predictive of response to these agents. However, other recent clinical data have highlighted an urgent need to elucidate optimal biomarkers based on genetic and/or protein diagnostics to correctly identify patients most likely to benefit in ongoing clinical trials of an array of MET-targeted therapies of differing class. The latest advances in the development of MET biomarkers in NSCLC have been reviewed, toward establishing appropriate MET biomarker selection based on a scientific rationale. .