Arecoline inhibits activation of STAT3, p190RhoGAP, and SHP2 and increases Rock-1 cleavage in HA22T/VGH cells. HA22T/VGH cells were treated with 0-100 μg/ml of arecoline for 24 h, then the cells were harvested and proteins extracted and used for Western blotting with antibodies against Gp130, phospho-Tyr705-STAT3 (STAT3-Tyr-p), p190RhoGAP, SHP2, or Rock-1; the Gp130, p190RhoGAP, and SHP2 blots were then stripped and re-blotted using antibodies against phospho-Tyr (Tyr-p). β-actin was used as the internal control. The values shown are the quantitative density analysis expressed as the relative density compared to that in untreated cells (control), taken as 100%. The results are expressed as the mean ± S.D. for three separate experiments. *: p < 0.05 as compared to the untreated control.