Heat shock protein 70 (HSP70) expression is associated with poor prognosis in intestinal type gastric cancer

Heat shock protein 70 (HSP70) is a molecular chaperone which plays an important role in cellular protection against various stressful stimuli and in the regulation of cellular growth and apoptosis. This study was conducted in gastric carcinoma (GC) to assess correlations of HSP70 expression with clinicopathological parameters and overall survival (OS). Tissue microarray blocks were constructed from 172 GCs and immunohistochemically stained for HSP70. Low HSP70 expression was found in 122 GCs (71 %), whereas 50 (29 %) had high expression. HSP70 expression was higher in tumours in the cardia (p = 0.008), with non-signet ring cell histology (p < 0.001), of intestinal type (p = 0.045) and of higher pathological T stage (p = 0.026). When considering the cohort as a whole, HSP70 expression did not correlate with OS (p = 0.092). In intestinal type carcinomas, however, high HSP70 expression significantly correlated with worse OS (p = 0.034). These results suggest that HSP70 expression might be an unfavourable prognostic factor in patients with GC, especially of intestinal type.