The mechanosensitive TRPV2 calcium channel controls melanoma invasiveness and metastatic potential.

Abstract

Discovery of therapeutic targets against metastasis is of primary importance since being the main cause of cancer-related death. Melanoma is a highly aggressive cancer endowed with a unique capacity of rapidly metastasizing. Deregulation of calcium homeostasis has been involved in numerous cellular metastatic behaviors, although the molecular determinants supporting these processes often remain unclear. Here, we evidenced a prominent expression of the plasma membrane TRPV2 calcium channel as a distinctive feature of melanoma tumors, directly related to melanoma metastatic progression and dissemination. In vitro as well as in vivo, TRPV2 activity was sufficient to confer both migratory and invasive phenotypes to non-invasive melanoma cells, while conversely upon TRPV2 silencing, highly metastatic melanoma cells failed to retain their malignant behaviors. We established a model whereupon activation of the mechanosensitive TRPV2 channel, localized in highly dynamic nascent adhesion clusters, directly regulates calpain-dependent cleavage of the adhesive protein talin together with F-actin network. By operating at the crossroad of the tumor microenvironment and the intracellular machinery, mechanosensitive TRPV2 channel controls melanoma cells aggressiveness. Finally in human melanoma tumor samples, TRPV2 overexpression represents a molecular marker of advanced malignancy and bad prognosis, highlighting a new therapeutic option for migrastatics in the treatment of metastatic melanoma. SignificanceOne essential feature of metastatic cells is enhanced motility and invasiveness. This study evidences TRPV2 channel control over metastatic melanoma invasiveness, highlights new migration regulatory mechanisms, and reveals this channel as a biomarker and migrastatic target for the treatment of advanced melanoma.