rhHAPLN1 inhibits PDGF-BB elevated HASMCs proliferation. (A) Ki-67 (green) and DAPI (blue) staining of HASMCs after treatment with 20 ng/ml rhHAPLN1 or 10 ng/ml PDGF-BB for 48 h. Representative images (left) and corresponding quantification of Ki-67-positive HASMCs (right) are shown. Scale bar: 100 μm. (B, C) Western blots examining the protein expression levels of FAK, p53, p21Cip1, p27Kip1, Cyclin D, CDK4, Cyclin E, and CDK2 in HASMCs after treatment with rhHAPLN1 (concentrations indicated on figure) or 10 ng/ml PDGF-BB for 48 h. GAPDH was used as a positive control. P-values indicated by # were calculated relative to untreated cells, whereas P-values indicated by * were calculated relative to PDGF-BB treated cells. * or # indicates P < 0.05, ** or ## indicates P < 0.001, *** or ### indicates P < 0.0005, and **** or #### indicates P < 0.0001 (N = 3 per group).