Figure 5

MCRS1 promoted EMT through the up-regulation of miR-155. (a) Screening strategy of miR-155. (b) The relative expression of miR-155 in NSCLC cell lines. (c) The level of miR-155 in clinical samples including 6 noncancerous lung tissue and 15 NSCLC tissues (Student’s t-test, *P <0.05). (d) Left: The map of miR-155 host gene (MIR155HG). Right: miR-155 was identified as a downstream target of MCRS1 using ChIP analysis; normal mouse IgG was used as the immunoprecipitation negative control. Input and immunoprecipitated DNAs were analyzed by PCR using primers specific for the promoter of the miR-155 host gene (MIR155HG). (e) miR-155 expression in EPLC-32 M1 and NCI-H292 cells with and without MCRS1 silencing. (f) Protein expression of RhoA (a target of miR-155) in EPLC-32 M1 and NCI-H292 cells after miR-155 treatment. (g) Protein expression of RhoA in EPLC-32 M1 and NCI-H292 cells with and without MCRS1 silencing. (h, i) The miR-155 inhibitor (miR-155 ASO) treatment decreased cell growth and invasion in cancer cells without MCRS1 silencing, and the miR-155 mimic treatment rescued the effects of MCRS1 with regard to cell growth and invasion in MCRS1–depleted cells. (j) The relationship between the level of miR-155 expression and the status of tumor metastasis (*P <0.05; one-way ANOVA and Student’s t-test). Luc: cells without MCRS1 silencing; Msh3: cells with stable MCRS1 silencing; NC: negative control. ASO: antisense oligonucleotide. Noncancerous: noncancerous lung tissues; No metastasis: NSCLCs without metastasis; Metastasis: NSCLCs with metastasis.