Aberrant deleted in liver cancer-1 expression is associated with tumor metastasis and poor prognosis in urothelial carcinoma

This study explored the potential role of deleted in liver cancer-1 (DLC-1) as a prognostic indicator of cancer metastasis and survival in urothelial carcinoma (UC). Tissue microarrays were constructed from paraffin-embedded specimens from 88 UC patients, and immunohistochemical staining was performed to investigate the association of DLC-1 with clinicopathologic characteristics and clinical outcome. The DLC-1 expression showed a significant positive correlation with tumor location (p = 0.041) and a significant negative correlation with advanced histological grade (p = 0.013). In tumors with low DLC-1 expression, Bcl-2 positivity was observed in 24.4% of cases. The DLC-1 expression had significant negative associations with Bcl-2 expression (p = 0.032) and with highly metastatic UC (p = 0.032). Kaplan-Meier analysis showed that DLC-1 protein expression was negatively associated with both overall survival (OS) (p = 0.035) and with distant metastasis-free survival (DMFS) (p = 0.041), but not with disease-free survival. Multivariate analyses indicated that tumor size was the significant independent predictors of OS (p = 0.048); however, only DLC-1 expression was a significant independent predictor of DMFS (p = 0.019). In conclusion, reduced DLC-1 protein expression may be an important factor in tumor progression and a useful prognostic molecular marker in UC.