According to a new study by researchers in the U.S. the popular prostate cancer treatment, androgen deprivation therapy, may in fact encourage the spread of cancer cells throughout the body.
It is common for men with advanced prostate cancer to be given therapy which blocks their body’s production or use of testosterone; this is because the hormone encourages the growth of prostate cancer.
The treatment 'androgen deprivation therapy' (ADT), is not considered to be a cure but is thought to delay the growth and spread of tumors which are inoperable.
However this new research suggests that the therapy encourages the production of a protein that makes the cancer cells more likely to proliferate.
The team at the Johns Hopkins School of Medicine do however say that their discovery is very much a preliminary one and they do not advise androgen deprivation therapy should cease as the therapy as it is effective at slowing down the growth of tumors.
The finding could however ultimately lead to changes in standard treatment for what can be a deadly disease.
The researchers identified the unsuspected potential problem with ADT following the discovery that the gene that codes for the protein Nestin was active in lab-grown human prostate cancer cells.
David Berman, an assistant professor of pathology, urology and oncology at Johns Hopkins and his colleagues became interested in whether prostate cancer cells in people also produce Nestin.
The team searched for Nestin in cells taken from men who had surgery to remove locally confined cancers of their prostates but found none.
However when they looked for Nestin in prostate cancer cells isolated from patients who had died of metastatic prostate cancer, where the cancer cells had spread out from the prostate tumor, they found substantial evidence that the Nestin gene was active.
Berman suggests that the difference was that androgen deprivation therapy is a treatment generally given only when prostate cancers become aggressive and likely to metastasize because the treatment is thought to slow tumor growth and weaken the disease.
Berman says patients who eventually die because their disease metastasizes are almost certain to have received this type of therapy.
The suspicion that by depriving cells of androgens might also affect Nestin expression, led the researchers to experiment on a prostate cancer cell line that depends on androgens to grow.
They found that when they removed androgens from the chemical mixture the cells live in, their production of Nestin increased.