Fatty Acid Binding Protein 6 Is Overexpressed in Colorectal Cancer

Purpose: Fatty acid binding protein 6 (FABP6) is a cancer-related protein that acts as an intracellular transporter of bile acid in the ileal epithelium. Because bile acids are implicated in the carcinogenesis of colorectal cancer, we evaluated FABP6 expression in colorectal cancer. Experimental Design: The expression of FABP6 mRNA was evaluated in 78 paired samples of cancer/normal tissue representing colorectal cancer cases, plus 16 adenomas, and 16 metastatic lymph nodes. An immunohistochemical study was conducted with paraffin sections. In vitro transfection was done to determine FABP69s biological roles. Results: The expression of FABP6 mRNA was significantly higher in cancer (75 of 78, 96.2%) than in normal tissue ( P P P P In vitro transfection revealed that transfectants showed weaker invasiveness ( P P Conclusions: The expression of FABP6 was higher in primary colorectal cancers and adenomas than in normal epithelium, but was dramatically decreased in lymph node metastases, suggesting that FABP6 may play an important role in early carcinogenesis.