High-level expression of Hsp90ß is associated with poor survival in resectable non-small-cell lung cancer patients.

AIMS: The aim of this study was to investigate the expression of Hsp90ß and GRP94, and elucidate the clinical significance of their expression, in patients with resectable non-small-cell lung cancer (NSCLC). METHODS AND RESULTS: Surgical tissue specimens were obtained from 208 patients with NSCLC who underwent surgical resection. The expression levels of Hsp90ß and GRP94 were assessed with tissue microarrays and immunohistochemistry. No correlations were observed between Hsp90ß or GRP94 expression and several clinicopathological factors. The high-Hsp90ß group [median overall survival (OS) 20.4 months; 95% confidence interval (CI) 0.000-40.864] showed a significant decrease in OS as compared with the low-Hsp90ß group (median OS not reached; P = 0.003). In contrast to the Hsp90ß analysis, the GRP94 analysis did not show a difference in OS. Moreover, in subgroup analyses of patients with squamous cell carcinoma histology, OS (P = 0.012) and relapse-free survival (P = 0.044) were significantly worse in the high-Hsp90ß group than in the low-Hsp90ß group. Multivariate analysis suggested that old age [hazard ratio (HR) 1.568; 95% CI 1.019-2.412; P = 0.041], advanced disease (HR 2.066; 95% CI 1.218-3.502; P = 0.007) and high Hsp90ß expression (HR 1.802; 95% CI 1.061-3.060; P = 0.029) were independent poor prognostic factors for OS. CONCLUSIONS: Hsp90ß expression might be a useful marker of poor OS, although further large prospective studies are warranted to validate our findings.