Fig. 8

miR-92b-3p inhibited cell growth and metastasis in PC in vivo. a-c Tumor growth curve and tumor weights after AsPC-1 cells stably expressing miR-92b-3p or empty vector were injected into nude mice. (Each group, n = 10) (d) Comparison of the tumor formation frequency for PC cells stably expressing miR-92b-3p or empty vector. The P value was assessed by log-rank test. e Effects of miR-92b-3p on tumor metastases in nude mice. f H&E staining of the liver after injection of AsPC-1 cells transfected with miR-92b-3p or empty vector. Scale bars: 50 μm. g-i Immunohistochemistry and qPCR analyses to detect the number of Ki-67⁺ cells and the protein and mRNA levels of Gabra3, MMP-2 and MMP-9 in tumor xenografts from the miR-92b-3p overexpression and control groups. Representative images from 10 separate samples are shown. Original magnification, ×400; Scale bars: 50 μm. j Gelatin zymography analyses to detect MMP-2 and MMP-9 activities in tumor xenografts from the miR-92b-3p overexpression and control groups. k Proposed model for how miR-92b-3p regulates PC cell proliferation and metastasis by targeting Gabra3 via the AKT/mTOR and JNK pathways. We propose that miR-92b-3p interacts with Gabra3 via its mRNA 3′-UTR. Then, Gabra3 stimulates the AKT/mTOR and JNK pathways; these effects increase the phosphorylation of p70sp6k as well as the protein levels and activities of MMP-2 and MMP-9, thus increasing proliferation and metastasis in PC. Bar, SEM; *P < 0.05; **P < 0.01; ***P < 0.001; Student’s t test or Fisher’s exact test