Prognostic and predictive value of MET deregulation in non-small cell lung cancer

Recent progress in cancer biology has led to the discovery of increasing number of oncogene alterations that have dramatically changed the paradigm of lung cancer treatment. MET is a tyrosine kinase receptor for the hepatocyte growth factor (HGF) that is deregulated in several malignancies, including non-small cell lung cancer (NSCLC). Abnormal MET-HGF signaling pathway activation can occur via different mechanisms, including HGF and/or MET overexpression, MET gene amplification, mutations or rearrangements. MET protein overexpression and increased MET gene number have been identified as poor prognostic factors in several series of surgically resected NSCLC making this receptor an attractive target for cancer treatment. Several clinical trials have recently evaluated the activity of a variety of anti-MET strategies in NSCLC patients with or without molecular selection with a variable degree of success, underscoring the need of establishing the best predictive biomarker for the identification of responding patients.