Fig. 3.

circPhf21a knockdown increased the proliferation and ECM anabolism of PMCs. A PMCs were transfected with circPhf21a siRNA or negative control siRNA at a final concentration of 20 nM. After 48 h of transfection, the expression level of circPhf21a was measured by RT-qPCR and normalized to Gapdh level. n = 3, ***p < 0.001, ****p < 0.0001. B PMCs were transfected with circPhf21a#3 siRNA (si-circPhf21a) or negative control siRNA (si-NC) at a final concentration of 20 nM. After 48 h of transfection, the expression level of Phf21a was measured by RT-qPCR and normalized to Gapdh level. n = 3, ns p > 0.05. C, D PMCs were transfected with si-circPhf21a or si-NC at a final concentration of 20 nM. After 48 h of transfection, the proliferation of PMCs was assessed using EdU assay. n = 3, ****p < 0.0001, scale bar = 50 μm. E–G PMCs were transfected with si-circPhf21a or si-NC at a final concentration of 20 nM. After 48 h, protein levels of Mmp13 and Col2a1 were determined by western blotting. n = 3, **p < 0.01. H PMCs were transfected with si-circPhf21a or si-NC at a final concentration of 20 nM. After 48 h, the mRNA expression levels of Mmp3, Mmp13, Adamts4, Col2a1 and Aggrecan were detected by RT-qPCR analysis in PMCs. n = 3, **p < 0.01, ***p < 0.001, ****p < 0.0001