A study on 5-Fluorouracil (5-FU) resistant colon cancer observed that an enzymatically active form of DPP4 is secreted into the microenvironment by various body fluids and high expression of DPP4 in poorly differentiated colon cancer tissues indicates that DPP4 activity in bodily fluids might be an efficient non-invasive diagnostic biomarker in CRC [62]. Here, DPP4 is linked to colorectal carcinoma.