Crizotinib, a MET inhibitor, prevents peritoneal dissemination in pancreatic cancer

Peritoneal dissemination is a frequent occurrence in pancreatic cancer, which is associated with a poor prognosis. MET is associated with the progression of pancreatic cancer; therefore, we evaluated the effect of a MET inhibitor, crizotinib, on peritoneal dissemination of pancreatic cancer. Crizotinib inhibited the growth of 8 pancreatic cancer cell lines with the IC50 ranging from 1.4 to 4.3 µM. Invasion of the pancreatic cancer cell line Suit-2, was suppressed in vitro at a concentration of 1.0 µM, which is sufficient for the inhibition of MET phosphorylation. This effect on cell invasion was also recapitulated by the reduction of MET expression in Suit-2 with siRNA. Crizotinib also inhibited RhoA activation in addition to MET phosphorylation. We further evaluated the effect of crizotinib on peritoneal dissemination of pancreatic cancer in vivo. Crizotinib reduced tumor burden and ascites accumulation due to development of peritoneal dissemination after inoculation of Suit-2. Taken together, crizotinib may be a potent drug for treating peritoneal dissemination of pancreatic cancer by inhibiting cancer cell proliferation and invasion, at least in part through the suppression of HGF/MET signaling and RhoA activation.