miR-155 regulates expression of RTKN2. (A) Effect of hsa-miR-155 overexpression on native RTKN2 and myosin light chain kinase protein levels in Raji, VAL, and MC116 cell line at 48 hours after transfection, assessed by Western blot. Actin levels were used as loading control. Densitometry analysis of normalized RTKN2 and myosin light chain kinase protein to actin are presented. The values in the control samples were arbitrarily defined as 1. Results are representative of 3 independent experiments. (B) Dual luciferase activity of reporter plasmids with the wild-type or mutated 3′-UTR of RTKN2 fused to the luciferase gene following hsa–miR-155 cotransfection in HeLa cells. The black columns represent cotransfections with hsa–miR-155; and the gray columns, the cotransfection of the same reporter vector with the nontargeting control. Mutations of the putative binding sites are represented as M1 and M2 3′-UTR and concomitant mutation of both sites as M1 + 2 3′-UTR. Values are normalized to the value of each control, which is noted as 100%. *Significant difference (P < .05). Error bars represent SEM.