PDGF-mediated inhibition of p27Kip1 by miR-221 Promotes Cell proliferation.

<p>(A, B): AsPC-1 cells were transfected with a negative control mimic, the miR-221 mimic, antisense oligonucleotides to miR-221 (anti-mIR-221) or p27Kip1 siRNA. The cells were then treated with PDGF-BB (20 ng/ml) for 24 h and subjected to qRT-PCR (A) and Western blot analysis (B) for p27Kip1. (C): AsPC-1 cells were transfected with negative control or p27Kip1 siRNA and subjected to the MTT cell proliferation assay (The results are indicated as the absorbance readings at 490 nm). (C) (D, E): AsPC-1 cells were transfected with a negative control mimic, the miR-221 mimic, antisense oligonucleotides to miR-221 (anti-mIR-221) or p27Kip1 siRNA. The cells were then treated with PDGF-BB (20 ng/ml) for 24 h and subjected to staining with a FITC-conjugated antibody against the proliferation marker PCNA and DAPI (E). In total, 150 cells were counted per condition, and the percentage of PCNA-positive cells is presented (D). All experiments in this figure were carried out in triplicate, and the results are displayed as the means ± SD.