CXCL1 and colorectal cancer: The marker for gastrointestinal cancer stem cells, dicortin-like kinin (DCLK1), promotes the growth of colorectal cancer by inhibiting the function of tumor-specific cytotoxic T-lymphocytes through the recruitment of myeloid-derived suppressor cells (MDSCs) via the CXCL1-CXCR2 axis (106).