This is common to relatively differentiated CRC cell lines (HT-29, HRT-18 and Caco-2) but not seen in less-differentiated cells such as those of the HCT-116, SW480 and SW620 lines, which express very low intrinsic levels of CD26 (Lefort et al., 2020). This evidence concerns the gene DPP4 and colorectal carcinoma.