miR-155 affects RhoA activation and F-actin polymerization. (A) Raji, VAL, and SUDHL6 lymphoma cells, transfected with hsa-miR-155 or control nontargeting miRNA 48 hours before the experiment, were starved for 8 hours and then treated with LPA (1.5 μg/mL) for 45 seconds. Cellular lysates were prepared, and RhoA pull-down assay was performed. HGAL knockdown and equal loading were confirmed by Western blot of HGAL, RhoA, and actin antibodies. Densitometry analysis of normalized RhoA-GTP to total RhoA is presented. The values in the control samples were arbitrarily defined as 1. Results are representative of 3 independent experiments. (B) Assay for polymerized F-actin. Raji, VAL, and SUDHL6 lymphoma cells, transfected with hsa-miR-155 or nontargeted control miRNA 48 hours before the experiment, were starved for 8 hours and then left unstimulated or treated with LPA (1.5 μg/mL) for 45 seconds followed by staining with Alexa-488 phalloidin and analyzed by flow cytometry.