Abstract: Objective To investigate the expression of heat shock protein 90（HSP90） in advanced gastric cancer and evaluate its impact on tumor invasion and prognosis of advanced gastric cancer. Methods The expressions of HSP90 in 157 advanced gastric cancer patients were determined by immunohistochemistry. The relationships between HSP90 and clinicopathological characteristics, prognosis of gastric cancer were analyzed. Results The high expression rate of HSP90 was 68.2％（107／157） in 157 advanced gastric cancer samples. The expression of HSP90 was closely related to tumor size，tumor site，depth of invasion，lymph node metastasis and clinical stage（P＜0.05）. In addition，the expression of HSP90 was significantly correlated with MMP-9 in gastric cancer tissues（r=0.514，P＜0.001）. The postoperative median recurrence-free survival（RFS）and overall survival（OS）of 157 gastric cancer patients were 27.0 and 33.0 months，respectively. The postoperative median RFS and OS of patients with low expression of HSP90 were both 60.5 months，while those of patients with high expression of HSP90 were 15.0 months and 20.0 months（P＜0.001，P＜0.001）. Cox regression model showed that HSP90 expression was an independent factor predicting the prognosis of gastric cancer（P＜0.05）.
Conclusion The expression of HSP90 is correlated with tumor invasion and metastasis，and the high expression of HSP90 indicates a poor prognosis.