APC and neoplasm: Interestingly, the TRα1 overexpression enhanced the intestinal tumorigenic process in the Apc+/1638N (40) animals (vil-TRα1/Apc+/1638N mice, hereafter designated as vil-TRα1/Apc) (15) while TRα-KO in the same Apc-mutated background retarded tumor development (16).