CXCL12 and breast cancer: In this context, genotype frequencies of CXCL12 polymorphism rs1801157 have been investigated in order to address its possible role in tumor pathogenesis in different conditions, including acute lymphoblastic leukemia [16], chronic myelogenous leukemia [33], breast cancer [34, 35], and Hodgkin’s lymphoma and non-Hodgkin’s lymphoma [35].