Pharmacy

A paired laboratory and epidemiological study has  identified the cardiac drug  digoxin as the basis for a new chemotherapeutic approach for the treatment of prostate  cancer.   Investigators   at Johns Hopkins University have screened 3,187 compounds that yielded digoxin as the most potent inhibitory agent.

The    investigators    then    evaluated epidemiological data from studies where incidence of prostate cancer was linked to digoxin use. This evaluation produced a cohort of about 47,000 men aged 40-75 who had participated in Harvard's Health Professionals Follow-up Study (HPFS) from 1986 through 2006 and did not have a cancer diagnosis before 1986. Results revealed that regular digoxin users, especially users for at least 10 years, had a lower prostate cancer risk. Thus, digoxin was both highly potent in inhibiting prostate cancer cell growth in vitro, and its use was associated with a 25 per cent lower prostate cancer risk.

Dr Elizabeth Platz, the first author and Professor-Epidemiology, Oncology and Urology, Johns Hopkins University, said, "We realized that combining our laboratory and epidemiologic approaches could reduce the possibility that results on the candidate drugs might be due to chance. Adding the epidemiology study to the drug screen step provided an assessment of the drug's potential activity in people." However, despite the promising findings presented in this study, digoxin was not shown to prevent prostate cancer, and the authors do not suggest the drug be used to prevent the disease.