TLR4 and cholangiocarcinoma: In the PSC setting, Zhang et al. reported a crucial role of intestinal flora composition in regulating anticancer immunity in CC by controlling the hepatic accumulation of polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) through the TLR4-dependent mechanism and the chemokine (C-X-C motif) ligand 1 (CXCL1)/C-X-C chemokine receptor 2 (CXCR2) axis, highlighting a relevant implication of dysbiosis in promoting carcinogenesis in mouse models [55].