RESUMO
OBJECTIVE: To investigate the effect of stachydrine on tumor growth of colon cancer and its mechanisms. METHODS: MTS was used to test the effect of stachydrine on proliferation of HCT116 colon cancer cell. HCT116 colon cancer xenograft model was used to detect the effect of stachydrine on tumor growth in vivo. Immunohistochemical was used to determine the effect of stachydrine on expression of smooth muscle actin 2 (ACTG2) in subcutaneous transplantation tumor. The transfection of ACTG2 siRNA into HCT116 cells was conducted to study the effect of ACTG2 intervene on tumor angiogenesis by tube formation experiment in colon cancer. The protein expression of VEGF, bFGF, TNF-α and PDGF after ACTG2 intervene were examined by Western blotting to explore the potential mechanisms of stachydrine on regulation of tumor angiogenesis. RESULTS: Compared with the control group, the proliferation and growth of HCT116 colon cancer cells were significant inhibited by stachydrine in vitro and in vivo. Immunohistochemical showed that the expression of ACTG2 was significantly decreased by treatment with stachydrine. ACTG2 siRNA transfection could significantly decreased the inhibition effect of stachydrine on tumor angiogenesis. Mechanistic study found that stachydrine could inhibit the expression of VEGF, bFGF, TNF-α and PDGF, however, ACTG2 siRNA transfection could significantly reverse the expression of above mentioned angiogenesis-related factors. CONCLUSION: Stachydrine could inhibit the growth of colon cancer by suppressing tumor angiogenesis, and such effect is dependent on ACTG2 expression.