Stress protein Hsp27 expression predicts the outcome in operated small cell lung carcinoma and large cell neuroendocrine carcinoma patients

Purpose: Heat shock protein (Hsp)27 is overexpressed in a range of human cancers and is implicated in tumor cell proliferation, differentiation, invasion, metastasis, and survival. The aim of the present study was to determine the prognostic significance of Hsp27 expression in small cell lung carcinoma (SCLC) and large cell neuroendocrine carcinoma (LCNEC). Methods: Surgically resected SCLCs (N=51) and LCNECs (N=15) were studied. The Hsp27 expression was detected immunohistochemically. Results: Hsp27 positive immunoreaction in the cytoplasm was observed in 45 (88%) SCLCs and 14 (93%) LCNECs. A combination of cytoplasmic with nuclear Hsp27 expression was observed in 28 (62%) SCLCs and 14 (100%) LCNECs. There was a correlation between Hsp27 cytoplasmic overexpression and Hsp27 nuclear expression with patient survival confirmed by Cox multivariate analysis. Conclusion: We conclude that the higher Hsp27 cytoplasmic expression and nuclear expression may represent favorable prognostic factors in SCLC and LCNEC.