Scientists in Wales today suggested they have found a way to slow down the metabolism of vitamins A and D, giving them the staying power to help men with advanced prostrate cancer that no longer responds to hormone therapy.Chemists at the Welsh School of Pharmacy in Cardiff said that prostate cancer is usually treated with hormonal therapy, but at some point the cancer generally becomes resistant to this treatment. It has been recognized for some time that vitamins A and D might have a therapeutic effect in hormone-refractory prostate cancer by suppressing the growth of cancer cells and restoring the control of cell growth that is lost in cancer. However, the researchers noted that the vitamins are metabolised quickly in the body and so do not stay around long enough to exert any anticancer effect.