FKA treatments do not affect Skp2 expression at the transcriptional levels (data not shown), but down-regulates the protein expression of Skp2 and induces the accumulation of p27 protein, a Skp2 substrate, in prostate cancer cell lines in a dose and time manner (Fig. 2A and Supplementary Fig. 2). The gene discussed is CDKN1B; the disease is prostate cancer.