Fig. 4.

miR-25-3p overexpression reverses CBR3-AS1-induced activation of the MAPK pathway and chemotherapy resistance in breast cancer cells. a Drug resistance was examined by CCK-8 assays in MCF-7 cells transfected with the CBR3-AS1 overexpression plasmid, miR-25-3p mimic or JNK1 inhibitor. b MCF-7 cells transfected with the CBR3-AS1 overexpression plasmid, miR-25-3p mimic or JNK1 inhibitor were seeded onto plates. The number of colonies was counted on the 14th day after seeding. c Apoptosis rates were detected at a concentration of 200 nM ADR in MCF-7 cells when CBR3-AS1 and miR-25-3p were overexpressed or when JNK1 was inhibited. d-e JNK1, MEK4 and P-gp expression was measured by western blot and qRT-PCR in cells overexpressing CBR3-AS1 and miR-25-3p. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001