Gastric cancer (GC) ranks the second prevalent cancer type and the second cancer-related death in China. However, the precise mechanisms of GC development remain poorly understood. Chronic infection with Helicobacter pylori is the strongest identified risk factor for GC. Toll-like receptor (TLR) genes, which play critical roles in Helicobacter pylori induced chronic inflammation, may also be implicated in GC susceptibility. TLR5 signaling deficiency could deregulate a cascade of inflammatory events. In current study, we systematically evaluated genetic variations of TLR5, and their interaction with Helicobacter pylori infection among carcinogenesis of gastric cancer, using a large case-controls study among Chinese population. Minor alleles of three SNPS, including rs5744174 (P = 0.001), rs1640827 (P = 0.005), and rs17163737 (P = 0.004), were significantly associated with increased GC risk (OR ranged from 1.20–1.24). Significant interactions with Helicobacter pylori infection were also identified for rs1640827 (P for interaction = 0.009) and rs17163737 (P for interaction = 0.006). These findings suggest that genetic variants in TLR5 may modify the role of Helicobacter pylori infection in the process of causing GC.

Esophageal squamous cell carcinoma (ESCC) has a high morbidity in China, accounting for 90% of all esophageal carcinoma cases. Hence, identifying drug targets for prevention and treatment of ESCC is essential. Due to its critical role in the regulation of cell apoptosis, Mcl-1 holds great potential as a target for treatment against ESCC. In current study, we used a 4-nitroquinoline-1-oxide (4-NQO)-induced ESCC mouse model of test whether A-1210477, a Mcl-1 small molecular inhibitor, could repress ESCC development. We showed that A-1210477 treatment decreased ESCC formation and animal weight loss in a dose dependent manner. We detected decreased cellular proliferation in A-1210477-treated ESCC tissue by Ki67 expression. Moreover, A-1210477 treatment increased the number of apoptotic cells in ESCC tissues. Our study clearly demonstrates the contribution of Mcl-1 to ESCC development through promoting cell proliferation and inhibition of apoptosis, and provides a strong evidence for further evaluation of A-1210477 for treating ESCC.