Binding of gut microbiota to Toll-like receptors (TLRs) on the surface of local cells generates lipopolysaccharides (LPS), activating inflammatory responses, increasing recruitment of inflammatory cells and cytokine secretion, promoting the expression of CXC receptor 2 (CXCR2), CXC ligands (CXCLs), STAT3, and IL-6, activating NF-kB, leading to oxidative stress imbalance in the microenvironment, DNA damage, and ultimately tumor formation (27). Here, CXCR2 is linked to neoplasm.