Epithelial-Mesenchymal Transition Phenotype, Metformin, and Survival for Colorectal Cancer Patients with Diabetes Mellitus II

Abstract

Objectives. We aimed to explore the association between metformin treatment and epithelial-mesenchymal transition (EMT) phenotype and further appraise the prognostic values of metformin and EMT markers E-cadherin and vimentin for colorectal cancer (CRC) in clinical practice. Methods. We collected specimens and evaluated clinicopathological parameters of 102 stage I to III CRC patients with prediagnosed type 2 diabetes mellitus (DM II). Expression of E-cadherin and vimentin in tumors was detected by immunohistochemistry (IHC), and statistical analysis was performed using SPSS 19.0. Results. In correlation tests, we found a lower tumor cell EMT degree (more E-cadherin (P=0.014) and less vimentin (P=0.011) expression in patients who used metformin, and the expression of E-cadherin and vimentin was associated with serum CA19-9 (P=0.048, P=0.009), tumor invasive depth (T) (P<0.001, P=0.045), and lymph invasion (N) (P=0.013, P=0.001). In Cox multivariate regression analysis, E-cadherin was identified as a prognostic factor for disease-free survival (DFS) (P=0.038) and metformin use (P=0.015P=0.044) and lymph invasion (P=0.016P=0.023) were considered as the prognostic factors for both DFS and overall survival (OS). Conclusion. Our study suggested that metformin may impede the EMT process and improve survival for stage I-III CRC patients with DM II.