HSP90B1 overexpression predicts poor prognosis in NSCLC patients

Non-small cell lung cancer (NSCLC) accounts for 85 % of lung cancer-related mortality worldwide. The heat shock protein 90B1 (HSP90B1) and DNA damage-inducible transcript 3 (DDIT3) are endoplasmic reticulum stress-related proteins that are associated with many malignancies. However, the roles of two proteins on NSCLC remain uncovered. To investigate the correlation between the expressions of HSP90B1 and DDIT3 and clinicopathological parameters of NSCLC as well as the significance of prognosis in NSCLC, a total of 143 NSCLC tissue samples and 45 control tissues samples were assessed. NSCLC patients were followed up from the day of surgery and ended by March 2014. The expressions of HSP90B1 and DDIT3 proteins were detected in all paraffin-embedded biopsy samples by immunochemistry. The HSP90B1 was highly expressed (65.2 %) in the 143 NSCLC patients, and its high expression was correlated with clinical stages (P = 0.001) and lymph node metastasis (P = 0.016). Similarly, DDIT3 was highly expressed in 43 (30.1 %) of 143 NSCLC patients, but only correlated with lymph node metastasis. Furthermore, Log-rank test suggested that high HSP90B1 expression may predict shorter survival (overall survival (OS)) and disease-free survival (DFS) for NSCLC patients. Cox model multivariate analyses indicated that HSP90B1 overexpression was an independent poor prognostic factor for both of OS and DFS. Therefore, HSP90B1 and DDIT3 may the potential biomarker to predict the NSCLC clinicopathological progress. Meanwhile, high HSP90B1 expression means poor prognosis, and HSP90B1 can be a promising prognosis factor for NSCLC.