PPARD and infectious otitis media: First, AOM-induced colon tumorigenesis was decreased in mice harboring the flanking LoxP sites surrounding the Pparb/d alleles but without Cre expression.61 Thus, expression of PPARβ/δ was not lost in the intestines of these mice but the same phenotype was observed in the mice with colonocyte-specific loss-of PPARβ/δ.