Fig 2: Let-7i-3p directly targets CCND1. (a) Putative WT and mutant‐type (MUT) let-7i-3p target sequences of CCND1 mRNA 3′-UTR. (b and c) Relative luciferase activity in HCT116 and 293T cells co-transfected with constructs carrying WT or mutant-type CCND1 mRNA 3′-UTR with let-7i-3p or NC. (d and e) The overexpression of let-7i-3p in the HCT116 cells attenuated the expression of CCND1 mRNA and protein levels, respectively, and a statistical histogram was shown at right (f). *P < 0.05 and **P < 0.01.

Fig 3: The relative (A) gene and (B) protein expression of CCND1 and p21 molecules in colonic tissues from the different groups is shown as bar graphs (n = 10 mice/group; data were analysed by ANOVA followed by Tukey’s HSD post hoc test and are shown as the mean ± SD; a = p < 0.05 compared with the NC group; b = p < 0.05 compared with the PC group; c = p < 0.05 compared with 5-FU monotherapy; d = p < 0.05 compared VD3 monotherapy; e = p < 0.05 compared with Met monotherapy; f = p < 0.05 compared with VF dual therapy; g = p < 0.05 compared with MF dual therapy; and h = p < 0.05 compared with VM dual therapy). (C) Localisation of CCND1 and p21 proteins by immunohistochemistry (IHC) in colonic tissues from the different groups (n = 10 mice/group; 20× objective; scale bar = 15 µm).

Fig 4: Silencing SNHG8 inhibited the proliferation, migration, and invasion of EBVaGC. (A) SNHG8 gene knockdown in AGS-BX1 cells (AGS-BX1/SNHG8-SH) had a low expression of SNHG8 quantified by qPCR as compared to vector alone control (AGS-BX1/NC) and wild-type cells (AGS-BX1). SNHG8 silencing reduced the malignant behaviors of AGS-BX1/SNHG8-SH cells in following aspects: the cell proliferation as measured with MTT assay (B); colony formation (C); cells in G0/1 (D); the expressions of proliferation-related-genes of BCL-2, CCND1, C=PARP, and PCNA demonstrated by qRT-PCR and Western blot (E, F); the migration measured with the wound healing assay (G, H); the invasion measured with the transwell invasive assay (I); and the expressions of invasion/metastasis-related-genes of Snail, VIM, CDH1, and CDH2 demonstrated by qRT-PCR and Western blotting (J, K). **p < 0.01; ***p < 0.001; ****p < 0.0001.

Fig 5: The expression of let-7i-3p and CCND1 in CRC cells. (a) The expression of let-7i-3p in four cell lines was determined by qRT-PCR. (b) The expression of CCND1 mRNA in four cell lines. (c) The expression of CCND1 protein in six cell lines was determined by western blot. (d) Quantification of CCND1 was normalized to α-tubulin. *P < 0.05 and **P < 0.01.