CCL2 and neoplasm: Furthermore, a previous study has shown that the overexpression of SUSD2 can increase the expression of CCL2 in MDA-MB231 cells (EGFR+) and that the knockdown of SUSD2 downregulates CCL2 levels in SKBR3 (EGFR+ HER2+) cells, implying that the SUSD2/CCL2 axis could lead to macrophage recruitment in the tumor microenvironment (TME) [12].