Studies have shown that CCL-4, -7, -8, -11, -15, -16, -19, -22, -23, -24, -25 and CXCL-5, -8, -9, and -16 were increased in breast cancer compared with normal adjacent breast tissue (Abrahamsson et al., 2017), and genetic polymorphisms near genes encoding CCL-2, -4, -5, -20, -22, CXCL-10, -12 and XCL-1 were found to be associated with the risk and prognosis of breast cancer (Eskandari-Nasab et al., 2014; Li et al., 2014; Jafarzadeh et al., 2015; Jafarzadeh et al., 2016; Stephens et al., 2017; He and Zhang, 2018; Hu et al., 2018; Chou et al., 2020). Here, CCL2 is linked to breast cancer.