Bioenergetic Alterations in Colorectal Polyp and Cancer

Background: The change of cellular energy metabolism in colorectal carcinogenesis is poorly understood. It is widely accepted tht most, if not all, colorectal cancers (CRCs) arise from adenomatous polyps (APs). Our aim was to characterize the mitochondrial and bioenergetic alternations in the adenoma-carcinoma sequence. Results: Two glycolysis-related genes, aldolase B (ALDOB) and solute carrier family 16 member 4 (SLC16A4), were upregulated in polyps. This result was further confirmed by the real-time PCR analysis showing that the both ALDOB and SLC16A4 mRNA expressions were higher in the polyps with villous component compared with their adjacent normal mucosa. 5 colon polyps with villous component and adjacent normal mucosa were included. Total RNA was isolated with TRIzol reagent (Invitrogen, Carlsbad, CA). Gene expression profiles of the human polyps and adjacent normal mucosa were analyzed with a human gene 2.0 array (Affymetrix, Santa Clara, CA). For real-time Q-PCR, first strand cDNA was synthesized with an oligo-T primer using superscript III first strand synthesis kit (Invitrogen, Carlsbad, CA). Gene expression of ALDOB, SLC16A4 and GAPDH mRNA were analyzed with the TaqMan® GENE expression assay (Applied Biosystem, Foster City, CA).