CXCR2 and neoplasm: Then we tested the protein expression levels of CXCR2 and TGF-β, because some studies have indicated that CXCR2 can also mediate PI3K/Akt/GSK-3β/Snail signaling pathway (25, 26), and many researches have revealed that CXCR2 is also significant in the recruitment of different cells (tumor-associated macrophages, tumor-associated neutrophils, myeloid-derived suppressor cells, regulatory T cells) which constitute the tumor microenvironment (29–32).