XPR1 and neoplasm: Modica et al (2008) have shown that loss of FXR in mouse models of intestinal tumorigenesis results in early mortality and increased tumour progression. Farnesoid X receptor deficiency has been shown to increase adenocarcinoma size in the small intestine of the APCmin mice and increase the prevalence and size of AOM-induced adenocarcinoma in the colon (Maran et al, 2009).