Angiotensin II type 1 receptor expression in human gastric cancer and induces MMP2 and MMP9 expression in MKN-28 cells.

Angiotensin II (Ang II), a main effector peptide in the renin-angiotensin system, acts as a growth-promoting and angiogenic factor via angiotensin II receptor1 (AT1R). In this study, we investigated the expression of angiotensin II type1 receptor (AT1R) in gastric cancer and the effects of Ang II on the expression of MMP2 and MMP9 in the human gastric cancer cell line MKN-28 cells. The expression of the Ang II type I receptor was examined by western and immunocytochemistry in gastric cancer cell lines and detected by real-time PCR and immunohistochemistry in normal and gastric cancer tissues. The expression of MMP2 and MMP9 were detected by real-time PCR and western after treatment with Ang II and/or AT1R antagonist. AT1R were expressed in all human gastric cancer lines and the expression of AT1R was significantly higher in cancer tissues than that in normal gastric tissues (P < 0.01). Furthermore, Ang II promoted the expression of MMP2 and MMP9 in MKN-28 cells, and the stimulatory effects of Ang II could be blocked by AT1R antagonist. These results suggest that AT1R is involved in the progression of gastric cancer and may promote the angiogenesis of gastric cancer cell line (MKN-28), and these effects may be associated with the upregulation of MMP2 and MMP9.