CXCR4 and neoplasm: Regarding the ability of CCL3 to promote the recruitment of fibroblasts, it should be mentioned that cancer-associated fibroblasts represent an important source for the chemokine CXCL12, which has also been linked to an immunosuppressive and thus tumor-promoting microenvironment in the context of CRC and whose receptor CXCR4 showed increased expression levels in the tumor tissue of CRC patients with poor clinical prognosis [29,55,56].