Figure 5.

c-Myc transactivates miR-21 expression by binding to the pri-miR-21 promoter. A. Correlation between c-Myc protein and miR-21 expression in B cell lymphoma lines. B, C. Ramos and OCI-LY10 were transfected with pCDH vector or pCDH-c-Myc for 48h, cell extracts were prepared and the levels of c-Myc and control GAPDH were determined by Western blot (B), and the miR-21 level was determined by qPCR (C). D, E. Ramos and OCI-LY10 were transfected with pLKO vector (control) or pLKO-c-Myc for 48 h, cell extracts were prepared and the levels of c-Myc and control GAPDH were determined by Western blot (D), and the miR-21 level was determined by qPCR (E). F. HEK293T cells was transfected with control pGL3.0, pGL3.0-miR-21-WT, and pCDH-c-Myc, or both, 48 h after transfection, the cells were lysed, and luciferase activity was measured. G. Schematic diagram of the locations of c-Myc-binding sites at the miR-21 promoter region (-1000 bp to +1 bp). H, schematic presentation of the pGL3.0 luciferase reporter constructs containing wild-type or mutant E boxes. I. HEK-293T cells were transfected with the pGL3.0 wild-type or mutants with pCDH-c-Myc, the cells were lysed, and luciferase activity was measured. J, K. Transfections were performed as in B or D, cell extracts were prepared and ChIP assays were performed. *, P < 0.05; **, P < 0.01; ***, P < 0.001.