Gene expression analysis of anti-PDL1 treated colon tumors from the murine enterotoxigenic Bacteroides fragilis (ETBF) tumorigenesis model.. Mus musculus

The multiple intestinal neoplasia (MinApc delta716/+) enterotoxigenic Bacteroides fragilis (ETBF) murine colon tumorigenesis model is characterized by IL-17-dependent, distal colon adenomas. However, the addition of the human BRAFV600E to create BRAFV600ELgr5CreMin (BLM) to the ETBF model results in the addition of tumors in the mid-proximal colon which differ from Min ETBF tumors in that they are infiltrated by CD8+ T cells and are characterized by FACS and gene expression as having INFg and Th1 gene expression patterns. Treatment with anti-PDL1 checkpoint therapy resulted in a significant reduction of tumors in BLM ETBF mice compared to Min ETBF mice. We used RNA sequencing in order to better understand the response of ETBF-induced BLM tumors to anti-PDL1 antibody treatment.Overall design: To characterize the response to anti-PDL1 therapy, we performed RNA sequencing on mRNA extracted from ETBF-induced BLM mid-proximal and distal and Min distal colon tumors following isotype or anti-PDL1 therapy.