Obesity accelerates murine gastric cancer growth by modulating the Sirt1/YAP pathway

A previous study from our group using an in vivo model demonstrated that diet induced-obesity increases the risk of gastric cancer and may prompt its growth. However, the molecular mechanisms underlying this association remain unclear and require further investigation. The aim of the present study was to investigate the potential molecular mechanisms through which obesity affects gastric cancer growth. In a subcutaneous mouse model, tumors were significantly larger in obese mice compared with non-obese and lean mice. In addition, markedly increased levels of Sirt1 and YAP protein were observed in the nucleus of cells from subcutaneous tumors from obese mice compared with those from lean mice. Murine forestomach carcinoma (MFC) cells treated with 5% sera from obese mice exhibited significantly increased expression of Sirt1 and YAP compared with MFC cells treated with sera from lean mice. In addition, a positive correlation was observed between Sirt1 expression and YAP expression, and between Sirt1 expression and serum visfatin levels in mice. These results suggested that diet-induced obesity could promote murine gastric cancer growth by modulating the Sirt1/YAP signaling pathway.