PTEN and cancer: In leukemia, RhoA/ROCK1/PTEN activation was critical to apoptosis induced by R-(−)-gossypol acetic acid (AT-101), a natural cottonseed product that exhibits anti-cancer activity, but the treatment with Y27632, or down-regulation of ROCK1 with siRNA lowered the effectiveness of the small molecule inhibitor (Li et al. 2014b).