KLK3 and neoplasm: The wet tumor weights or serum PSA in control and flavokawain B–treated group recorded at the end of the treatment are 0.43±0.27 g and 0.097±0.048 g, or 66.6±12.8 ng/mL and 18.4±4.8 ng/ml, respectively (mean ± SD; n = 13 for control and n = 6 for FKB treatment groups; P<0.001, Student's t test).