the instant invention is directed to the use of a pharmaceutical composition containing an effective amount of adenosine or an adenosine analog or derivative as an agent useful in the treatment of hormone - independent cancers , such as prostate cancer . the invention is also directed to diagnostic uses of these compounds to determine effective treatment regimes for specific tumors , a process for screening for new , therapeutically useful analogs of these compounds , and the use of these compounds in facilitating the extraction of intracellular components .