Prognostic Correlation Between MFG-E8 Expression Level and Colorectal Cancer

Abstract

Colorectal cancer (CRC) is one of the leading causes of cancer-related death all over the world. Milk fat globule-epidermal growth factor (EGF)-factor VIII (MFG-E8) was found to be highly expressed in a variety of cancers. However its role in CRC is unclear. This study investigates the expression of MFG-E8 in CRC tissues and the correlation with clinicopathological features and prognosis in CRC patients. The expression of MFG-E8 proteins was detected by immunohistochemical staining in 90 samples of CRC. The localization of MFG-E8 in colorectal tumor was examined by immunofluorescence staining. The correlation between MFG-E8 protein expression and the clinical pathological features of CRC were evaluated by χ2 test and Fisher's exact test. The survival rates were analyzed by the Kaplan-Meier method, and the relationship between prognostic factors and patient survival was analyzed by the Cox proportional hazard models. Our results showed that MFG-E8 expression increased significantly in colorectal cancer compared with normal mucosa tissues (p <0.001). We further validated MFG-E8 overexpression in 6 pairs of fresh tumor and adjacent normal mucosa tissues from colorectal cancer patients by Western blot (p <0.05). Immunofluorescence staining showed that MFG-E8 accumulated in close proximity to endothelial cells in human colorectal tumor tissue. In addition, high MFG-E8 protein expression was correlated with lymph node metastasis and some pathological classifications (p <0.05). Furthermore, patients with high protein level of MFG-E8 showed shortened overall survivals (p <0.05). Our results showed that MFG-E8 could be a potential novel prognostic marker for CRC and overexpression of MFG-E8 might be involved in lymph node metastasis and angiogenesis of CRC.