CXCL12 and neoplasm: Cancer-associated immune modulation is achieved via certain secretory products that include but are not limited to (i) cytokines (e.g., interleukins), (ii) chemokines (e.g., SDF-1) that promote the activation of tumor-associated macrophages, and (iii) establishment of an acidic tumor microenvironment (TME) that renders majority of antitumor immune cells less efficient or non-functional (8).