PGC-1 expression level in human colorectal cancer: A predictor of lymph node metastasis

Abstract

3616 Background: Previous study showed that the expression of peroxisome proliferator-activated receptor γ (PPARγ) and PPARγ coactivator-1 (PGC-1) was correlated with clinical outcome in breast cancer. However, no published data are available about the biological and clinical significance of PGC-1 in colorectal cancer. Thus, our aim was to explore the expression of PPARγ and PGC-1 in colorectal cancer as well as their association with other clinicopathological features, and to evaluate the role of PPARγ and PGC-1 as a prognostic indicator of colorectal cancer. Methods: We have investigated the presence of PPARγ and PGC-1 in human colorectal cancer tissues and adjacent normal tissues from 108 primary colorectal cancer patients by immunohistochemistry. The correlation between their expression and clinicopathologic features was investigated. Three-year overall survival of patients with different expression of PPARγ and PGC-1 were analyzed by the Kaplan-Meier method. Results: No significant correlation was found between PPARγ expression and age at surgery, gender, histopathologic differentiation, depth of infiltration, relapse, and Dukes’ stage. No significant correlation was found between PGC-1 expression and age at surgery, the histopathologic differentiation, the depth of infiltration, and relapse. However, PGC-1 expression was closely related to Duke’s stage and nodal metastasis (p=0.024 and p=0.020, respectively). Survival analysis showed that the PGC-1-positive group has a reduced overall survival (p=0.0367). Conclusions: Based on our results, PGC-1 may be valuable marker of nodal metastasis and represent a biomarker of poor prognosis in colorectal cancer. No significant financial relationships to disclose.