Fig. 5

MSI2a binds to TP53INP1 mRNA, increasing TP53INP1 expression and suppressing ERK1/2 activation. a Diagrams of the MSI2-targeted mRNA TP53INP1. b Heatmap showing that 17 mRNAs were associated with p53 signaling and enriched by MSI2a. c Heatmap showing the expression levels of 17 mRNAs associated with p53 signaling after RNA-Seq analysis. d Heatmap showing the changes in gene expression associated with ERK signaling after RNA-Seq analysis. e RIP assay was performed using cell extracts prepared from Hs-578T cells with an MSI2a-specific antibody or isotype-matched IgG. The level of TP53INP1 mRNA was quantified by using qRT-PCR, while Western blotting showed the specificity of the MSI2a antibody. f qRT-PCR analysis of TP53INP1 mRNA and Western blot analysis of the MSI2, TP53INP1, p-ERK1/2, and ERK1/2 proteins after MSI2a overexpression or knockdown in these TNBC cells. g MSI2a and TP53INP1 expression levels were analyzed in MSI2a-overexpressing MDA-MB-231 and MDA-MB-468 cells by immunofluorescence staining. Green and red represent MSI2a and TP53INP1, respectively. h TP53INP1 staining of xenograft tissues of mice injected with MSI2a-overexpressing MDA-MB-231 cells. Scale bar, 100 μm. *p < 0.05, **p < 0.01, ***p < 0.001