(A) miRNA activity profiles for HEK293 and HEK293T were established using the miRNA Asensor arrays. (B) Several miRNAs were selected and their activities compared. Compared to HEK293T cells, miR-17-5p, miR-18a, miR-20a, and miR-106a activities were lower in HEK293 cells, while miR-21, miR-222, let-7a, let-7b, let-7c, let-7e, and let-7f were higher. (C) miR-21 expression level was detected by QRT-PCR. The miR-21 activity was consistent with its expression level in the two cell lines. 2ΔCt was used to indicate the miRNA expression levels. ΔCt = CtU6−CtmiRNA. RIF, relative inhibiting fold. Error bars correspond to mean±SD (n = 3). Student T test was used for statistical anylasis. *indicates P values<0.05 and ** P values<0.01.