Ang1 and Ang4 differentially affect colitis and carcinogenesis in an AOM-DSS mouse model.

Abstract

IntroductionAngiogenin-1 (Ang1) and angiogenin-4 (Ang4) are 14-kDa ribonucleases with potent angiogenic and antimicrobial properties. The role of Ang1 and Ang4 in chronic colitis and colitis-associated cancer has not been previously studied.MethodsWild-type (WT) and angiogenin-1 knock-out (Ang1-KO) C57BL/6 mice were given azoxymethane, a colon carcinogen, 2 days in advance of three cycles of 3.5% dextran sodium sulfate (DSS). Disease activity index (DAI) was recorded, a colonoscopy was performed after each DSS treatment, and mice were euthanized (colitis, recovery, cancer) with tissue evaluated by histopathology. Ang1, Ang4, TNF-α, Il-1F062, IL-6, IL-10, IL-23, IL-33 mRNA levels were analyzed by RT-PCR.ResultsAng1-KO mice exhibited more severe colitis compared to WT mice during both the acute (PConclusionsIn a mouse model of colitis-associated cancer, Ang1-KO mice develop more severe colitis, but fewer tumors compared to WT mice. Ang1 levels correlate with the severity of colitis and the development of colitis-associated cancer, while Ang4 was upregulated during both colitis and cancer. Ang1 and Ang4 play important regulatory roles in the response to chronic colitis and the development of colitis-associated cancer and may serve as novel therapeutic targets.