BAP1 is a good prognostic factor in advanced non-small cell lung cancer

Purpose: Non-small cell lung cancer (NSCLC) is the leading worldwide source of cancer-related deaths. Although some drugs targeting epidermal growth factor receptor (EGFR) mutations have been developed, most advanced NSCLC is still incurable and new targets for anticancer drugs are in demand. BRCA1-associated protein-1 (BAP1) is a component of the ubiquitin proteasome system (UPS). UPS has emerged as a potential target for anticancer drugs. The aim of the present study was to investigate the expression of BAP1 protein in patients with NSCLC. Methods: BAP1 expression was measured using Western blot analysis in 103 cases patients with advanced NSCLC. Results: Results revealed 49 (47.5%) patients were classified with high expression of BAP1. Squamous cell carcinomas were more likely to be observed in BAP1 high expressers compared with adenocarcinomas (55.8% vs. 32.3%, p = 0.001). High BAP1 expression was associated with no lymph node metastasis (p = 0.002). There was also a significant association between BAP1 expression and histological type (p = 0.014), while expression of BAP1 was not correlated with other clinical or pathological characteristics. Kaplan-Meier survival analysis showed that patients with high BAP1 expression had a longer median survival compared with patients with low BAP1 expression (23.2 vs. 14.7 months, p = 0.021). Multivariate analysis revealed that high BAP1 expression was an independent lower risk for all 103 patients (HR = 0.61, 95% CI 0.32-0.71, p = 0.003). Conclusions: BAP1 may be a useful prognostic factor of NSCLC patients and potential target for anticancer drugs.