DPP4 and colorectal carcinoma: Hereby, in this study, we aim to investigate whether dysregulation of stem cell markers, including Oct4, ALDH1A1, CD133, CD166, CD24, CD26, CD29, CD44, c-MYC, CXCR4, EpCAM, LGR5, LRIG1, Msi1, and SOX2, is detected in patients with CRC and to evaluate if rectal swab samples may serve as a tool for gene expression analysis and CRC screening.