AHR and colonic neoplasm: Here, we found that the AhR antagonist CH-223191 inhibited the proliferation of HT-29 and HCT116 cells (in a similar manner as AhR KO), which seems to provide further support to the hypothesis that the AhR plays a positive role in the control of colon cancer cell proliferation, perhaps in a similar manner as in the above discussed models of liver carcinoma cells.