CDKN1B and Familial prostate cancer: Even though information is lacking regarding the effect of PEITC on p57 gene expression, there are several studies which have shown that PEITC can induce other regulators of cell cycle progression at G1, such as p21WAF-1/Cip-1 and p27Kip1, resulting in a cell-cycle arrest in the G1-phase in vascular smooth muscle cells in vitro [43], and prostate cancer cells in xenograft mice [44].