Fig. 4

Protein tyrosine phosphatase receptor type B (PTPRB) is downregulated in OS tissues and is a target of miR-624-5p. a–c. PTPRB expression was markedly lower in OS tissues. d. PTPRB expression level was negatively related to miR-624-5p level in OS tissues. e. The mRNA levels of PTPRB were downregulated in several OS cell lines, especially in MG63 and U2OS cells (n = 4). f. MG63 and U2OS cells contained the least PTPRB protein compared with the other cell lines (n = 4). g. Kaplan-Meier analysis demonstrates that patients with high PTPRB expression levels had a much better prognosis based on an online database (https://hgserver1.amc.nl/cgi-bin/r2/main.cgi). h. The WT-PTPRB-3′-UTR and MUT-PTPRB-3′-UTR were synthesized. Overexpressed miR-624-5p markedly suppressed the luciferase activity of WT-PTPRB-3′-UTR but had no effect on MUT-PTPRB-3′-UTR in MG63 and U2OS cells (n = 5). I. qRT-PCR shows that the PTPRB mRNA expression level was negatively regulated by miR-624-5p (n = 4). j. Western blotting results support that miR-624-5p negatively controls the expression level of PTPRB (n = 3)