NFKB1 and prostate cancer: For example, Lee et al. demonstrated that 4-O-methylhonokiol (MH), a PPARγ agonist, has antitumor activity in prostate cancer through increased PPARγ activity and p21-mediated suppression of NF-κB activity as observed by the loss of MH-induced growth inhibition and NF-κB inhibition in a p21 siRNA knockdown experiment [25].