Abstract C204: Inhibition of c-Met signaling in combination with cisplatin and 5-fluorouracil significantly enhances antitumor effects in gastric cancer models

Abstract

Abstract Gastric cancer is currently the second most frequent cancer-related cause of death with an incidence rate of approximately one million cases annually. The present worldwide standard of care treatment regimen for gastric cancer is the combination of 5-fluorouracil (5-FU) and platinum analog (cisplatin). Many receptor tyrosine kinases are deregulated in gastric cancer including erbB2, c-Met, and EGFR. The purpose of our study was to dissect the role of c-Met signaling in gastric cancer and test the effects of our c-Met inhibitor (MK-8033) alone and in combination with the standard of care agents 5-FU and cisplatin. As a monotherapy, MK-8033 potently inhibited proliferation in a panel of gastric cancer cell lines in vitro. When administered simultaneously with cisplatin and 5-FU, the effects of the combination were diverse, ranging from additive to antagonistic. Altering the treatment schedule by the addition of 5-FU and cisplatin prior to MK-8033 resulted in an overall combination benefit across the panel. In a gastric cancer xenograft model, while MK-8033 alone significantly inhibited tumor growth progression, the co-administration of 5-FU and cisplatin with MK-8033 showed greater benefit than either the monotherapy or the standard regimen. In vitro cell cycle and survival analysis support the observed in vivo data, and provides a mechanistic rationale for the observed combination benefit. Our data suggest the combination of c-Met inhibitors with standard of care agents 5-FU and cisplatin may be beneficial in gastric cancer patients with activated c-Met signaling. Citation Information: Mol Cancer Ther 2009;8(12 Suppl):C204.