Exosomal lncRNA PVT1/VEGFA Axis Promotes Colon Cancer Metastasis and Stemness by Downregulation of Tumor Suppressor miR-152-3p

Figure 4

PVT1 silencing suppressed colon tumorigenic and metastatic potential. (a) The siRNA knockdown effect of PVT1 on two colon cancer cell lines. (b) The basal levels of PVT1 and VEGF (Western blot and gene expression) in cell lysates and exosomes. (c) Colony formation assay revealed that si-PVT1-transfected HCT116 and LoVo cells formed a significantly lower number of colonies compared with control parental cells. (d) Comparative tumorsphere-forming assay. HCT116 and LoVo cells transfected with si-PVT1 were significantly less potent in forming tumorspheres compared with their parental cells. (e) Comparison of expression between parental colon cancer cells and PVT1-silenced cells. Right panels: qPCR analysis demonstrated markedly decreased expression of metastatic markers, namely, VEGFA, Twist1, and MMP2, and the oncogenic marker EGFR in si-PVT1 colon cells. Left panels: Western blots of parental versus PVT1-silenced HCT116 and LoVo cells. Prominent reduction in the expression of VEGFA, Twist1, MMP2, and EGFR was observed after PVT1 silencing in both cell lines. Effect of PVT1 expression on cell (f) migration and (g) invasion of HCT116 and LoVo cells detected using Transwell assays. NC: negative control (scramble PVT1 oligonucleotides). ; ; . Scale bar: 100 μm.

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