DPP4 and colorectal carcinoma: For clinical trials in the future, we suggest that the DPP4-inhibitor treatment for CRC patients could be started with the routine clinical dosage, but a higher dosage can be considered if the patients do not respond well to the treatment based on pre-/post-treatment changes in lymphocyte count, PNI, NLR, PLR and PLT count as we mentioned in Section 3.3.