RNA-seq analyses of STAT1-delta IEC ApcMin (n=3) and STAT1-flox/flox ApcMin (n=3) mice

The interferon-inducible transcription factor STAT1 is a tumor suppressor in various malignancies. We investigated STAT1 functions in intestinal tumorigenesis of ApcMin mice. Surprisingly, loss of STAT1 in intestinal epithelial cells (STAT1?IEC) interfered with ApcMin induced intestinal tumor formation and tumor progression. RNASeq data demonstrated reduced expression of Indoleamine-2,3-dioxygenase-1 (IDO1) in STAT1?IEC ApcMin tumors. IDO1 is implicated in synthesis of kynurenine, a metabolite that induces ß-Catenin nuclear localisation and suppresses anti-tumor immune responses.