Prognostic significance of heat shock protein 70 expression in early gastric carcinoma

Background: Overexpression of heat shock protein 70 (HSP70) has been observed in many types of cancer including gastric adenocarcinomas, although the exact role of HSP70 in carcinogenesis remains unclear.

Methods: The study analyzed a total of 458 radical gastrectomy specimens which were immunohistochemically stained with HSP70, p53, and Ki-67 antibodies.

Results: The study determined that the expression of HSP70 was significantly increased in early gastric cancer (EGC) compared to advanced gastric cancer (p<0.001). The HSP70 expression was correlated with well-differentiated tumor type, intestinal type of Lauren classification and the lower pT and pN stage. Negative expression of Ki-67 and p53 expression was associated with poor prognosis. The study did not find any correlation between HSP70 and p53 expression. The study determined that HSP70 expression in the EGC subgroup was associated with a poor prognosis (p=0.009), as well as negative Ki-67 expression (p=0.006), but was not associated with p53. Based on multivariate analysis, HSP70 expression (p=0.024), negative expression of Ki-67, invasion depth and lymph node metastasis were determined to be independent prognostic markers.

Conclusions: HSP70 is expressed in the early stages of gastric adenocarcinoma. In EGC, HSP70 is a poor independent prognostic marker and is correlated with a low proliferation index.