Newly discovered testosterone effect may act on prostate cancer

Apr 6 2006

A newly-discovered mode of action of testosterone is showing great promise in the fight against prostate cancer, with tests showing a 60% reduction in tumor size in mice.

Testosterone has been associated with a higher rate of certain cancers. Classically, testosterone passes through the cell membrane to act inside the cell. However recent work has indicated that testosterone may also act at the cell surface, through receptors called Ambs (androgen membrane binding sites).

Now a team led by Professor Christos Stournaras (University of Heraklion, Greece) has discovered that activating these cell-surface testosterone binding sites can significantly reduce the size of prostate cancer tumours.

When testosterone is bound to another protein such as BSA, it does not enter the cell, and so can only be expressed at the cell membrane. Professor Stournaras’s team treated mice which had been given prostate cancer through inoculation with LNCaP cancer cells. They found that after one month of treatment with testosterone bound to the protein BSA (Bovine Serum Albumin) there was a 60% reduction in tumour size, with no apparent side-effects.

Professor Stournaras said: "This work strongly supports the concept that drugs which activate membrane androgen receptors may represent a new class of anti-tumour agents in prostate cancer. This is new, and we need to make sure that these results can be transferred to humans in a satisfactory way. But if we can develop drugs which act safely on these Ambs (androgen membrane binding sites) then we will have a completely new therapeutic option for prostate cancer".