miR-34a Regulates Multidrug Resistance via Positively Modulating OAZ2 Signaling in Colon Cancer Cells

Figure 5

OAZ2 overexpression abolishes miR-34a deficiency-induced oxaliplatin-resistance. (a) HCT-8/OAZ2 cells were established as described in Materials and Methods. OAZ2 overexpression was confirmed by immunoblotting analysis. pcDNA3.1+/DYK vector is expressed in mammalian cells as a tagged protein with a C-terminal DYKDDDDK tag (DYKDDDDK is the same as FLAG® which is a registered trademark of Sigma-Aldrich). (b) RT-qPCR analysis of miR-34a expression in HCT-8/OAZ2 cells. (c) HCT-8/OAZ2 cells with different transfections were incubated with different doses of oxaliplatin for 24 h, followed by cell viability assay. Different superscript letters denote groups that are statistically different (). (d) HCT-8/OAZ2 cell-derived tumor xenografts model was established as described in Materials and Methods. Tumor volumes were measured every 4 days. and when comparing DYK-OAZ2 + miR-34a inhibitor to miR-34a inhibitor alone. (e) HCT-8/OAZ2 cells were transiently transfected with miR-34a inhibitor or Inhibitor NC for 48 h, followed by immunoblotting analysis of the expression levels of OAZ2, MRP2, P-gp, BCRP, and Bcl-2. (f) Proposed working model in the current study.

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