The designed compounds, which were actually hybrids of vorinostat and coumarin, were initially tested against two breast carcinoma (i.e., BT-474 and MDA-MB-231) and one prostate cancer (i.e., PC-3) cell lines to choose the most potential hits and some of these were found to downregulate the expressions of cell-cycle regulatory genes such as p21, p53 and cyclin D1 (CD1) in both breast and prostate cancer cells. This evidence concerns the gene CCND1 and Familial prostate cancer.