CXCL12 and colorectal cancer: Previous studies, largely focused on the expression of CXCR4 on human colorectal cancer cells, suggested that the regulation of the CXCL12/CXCR4 axis in colorectal cell migration, proliferation, and invasion correlated with poor-prognosis angiogenesis [34]; however, the mechanism by which CXCR4 affects Bcl-2 expression in OXA-resistant cells remains unclear.