OBJECTIVETo investigate the essential role and mechanism of TRPC6 gene in the development of gastric cancer.

METHODSThe expression of TRPC6 protein was assessed in gastric cancer tissues and normal tissues adjacent to the cancer from 30 patients with gastric cancer. The inhibiting effect of TRPC6 activity on cell growth, cell cycle of a human gastric cancer cell line AGS cells, tumor progression and development of xenografted human gastric cancer in a mouse model was tested using dominant-negative mutant TRPC6 (DNC6). The survival of mice bearing xenografted tumors in the GFP and DNC6 was compared using Kaplan-Meier analysis. All statistical tests were two-sided.

RESULTSThe TRPC6 protein in the tumor tissues and para-tumor tissues was (21.60 ± 8.32)% versus (7.14 ± 2.24)%. After transfection of DNC6 virus for 24 hours, 48 hours, 72 hours and 96 hours, the growth inhibition rates of gastric cancer cells were (36.90 ± 1.13)%, (44.06 ± 2.17)%, (52.12 ± 2.76)% and (50.89 ± 1.97)%, respectively. The clone formation rates of control group and DNC6 group were (14.70 ± 3.00)% versus (43.80 ± 7.00)%. After transfection with DNC6 virus for 0, 24, 36 and 48 hours, the G(2)/M phase arrest was (20.34 ± 1.98)%, (24.31 ± 2.37)%, (27.70 ± 2.36)%, (35.10 ± 3.0)% in the DNC6 group and (18.40 ± 2.01)%, (18.0% ± 1.72)%, (17.50 ± 1.74)%, (16.80 ± 1.71)% in the control group, respectively. Inhibition of TRPC6 activity also reduced the subcutaneous tumor volume in the mouse models with xenografted human tumors (P < 0.05).

CONCLUSIONIn the preclinical models tested, TRPC6 channels are essential for gastric cancer development via regulation of G(2)/M phase transition.