Kewei Jiang1, Liang Lyu1, Zhanlong Shen1, Jizhun Zhang1, Hui Zhang1, Jianqiang Dong2, Yichao Yan1, Fangfang Liu3, Shan Wang4. 1. Department of Gastroenterological Surgery, Peking University People's Hospital, Beijing 100044, China. 2. Central Laboratory, Peking University People's Hospital, Beijing 100044, China. 3. Department of Pathology, Peking University People's Hospital, Beijing 100044, China. 4. Department of Gastroenterological Surgery, Peking University People's Hospital, Beijing 100044, China. Email: shanwang60@sina.com.
Abstract
BACKGROUND: Sirtuin 1 (SIRT1) has been reported to have diverse roles in various biological processes through deacetylation of histone and nonhistone proteins. However, the correlations among SIRT1 protein expression, clinicopathological parameters, and survival of colorectal cancer patients remain unclear. METHODS: SIRT1 protein expression was measured by immunohistochemistry in a paraffin-embedded tissue microarray, including 120 paired colorectal cancer and normal mucosa tissues. The correlations among SIRT1 protein expression, clinicopathological features, and prognosis were analyzed. RESULTS: All samples (100%) were positive for SIRT1, with variable staining in the cytoplasm rather than in the nucleus. There was significant difference in SIRT1 overexpression between adenocarcinomas and normal mucosal tissue (P < 0.01, χ(2) test). SIRT1 overexpression was more frequently observed in advanced-stage tumors (P = 0.046, 0.002, χ(2) test). SIRT1 overexpression was significantly correlated with poor overall survival (P = 0.013, log-rank test) and diseasefree survival (P = 0.012, log-rank test). CONCLUSIONS: SIRT1 overexpression correlated with advanced stage and poor prognosis. SIRT1 may play an important role in the progression of colorectal cancer.
BACKGROUND:Sirtuin 1 (SIRT1) has been reported to have diverse roles in various biological processes through deacetylation of histone and nonhistone proteins. However, the correlations among SIRT1 protein expression, clinicopathological parameters, and survival of colorectal cancerpatients remain unclear. METHODS:SIRT1 protein expression was measured by immunohistochemistry in a paraffin-embedded tissue microarray, including 120 paired colorectal cancer and normal mucosa tissues. The correlations among SIRT1 protein expression, clinicopathological features, and prognosis were analyzed. RESULTS: All samples (100%) were positive for SIRT1, with variable staining in the cytoplasm rather than in the nucleus. There was significant difference in SIRT1 overexpression between adenocarcinomas and normal mucosal tissue (P < 0.01, χ(2) test). SIRT1 overexpression was more frequently observed in advanced-stage tumors (P = 0.046, 0.002, χ(2) test). SIRT1 overexpression was significantly correlated with poor overall survival (P = 0.013, log-rank test) and diseasefree survival (P = 0.012, log-rank test). CONCLUSIONS:SIRT1 overexpression correlated with advanced stage and poor prognosis. SIRT1 may play an important role in the progression of colorectal cancer.