(B) RT-qPCR quantification of relative pri-miR-21, pre-miR-21, miR-21-5p and miR-21-3p levels in HaCaT cells treated for 24h with 2 or 5ng/ml of recombinant human TGFβ-1 (+) or vehicle (-) as indicated. Pri-miR-21: Veh vs TGF-1 5ng/ml P = 0.029; Pre-miR-21: Veh vs TGF-1 5ng/ml P = 0.001; miR-21-5p: Veh vs TGF-1 5ng/ml P = 0.002; miR-21-3p: Veh vs TGF-1 5ng/ml P = 1.7E-05. N=3 biological replicates, one representative experiment is shown out of two independent replicates . 