HFD promotes CAC development depending on the gut microbiota. (A) Experimental design for dietary and antibiotics treatment in a CAC mouse model. (B) Weight change in CD-fed, HFD-fed, and ABX-treated HFD-fed mice before sacrifice. (C) Macroscopic polyps (arrows) were identified in the distal and mid colons. (D) Day-60 weight alteration in CD-fed, HFD-fed, and ABX-treated HFD-fed mice before sacrifice. (E-F) The number (E) and maximal cross-sectional area (F) of macroscopic polyps were quantified. (G) Representative pictures of H&E staining in each group. Scale bar = 100 μm. (H) Immunofluorescence staining for ZO-1 in mouse colons. (I) Quantitative analysis of ZO-1 index. (J) Quantitative analysis of pathologic score was calculated according to the following criteria: 0, normal; 1, LGD; 2, HGD; and 3, carcinoma. H&E, hematoxylin and eosin; LGD, low-grade dysplasia; HGD, high-grade dysplasia. CD-fed, n = 8; HFD-fed, n = 8; and ABX-treated HFD-fed, n = 8. ns, no significance; *, P < 0.05; **, P < 0.01; ***, P < 0.001.