A new study shows that an antidepressant could be crucial in helping cancer treatment drugs reach their full potential.
The study by scientists at the Institute of Cancer Research found that tranylcypromine (TCP - cis and trans iosmers - below structures) – which can be used to treat psychotic depressive states - can make cancer cells vulnerable to the effects of a vitamin A- derivative drug called ATRA (above structure).
Retinoids are a class of chemical compounds related chemically to vitamin A. ATRA is already used successfully to treat a rare form of acute myeloid leukemia (AML), but up until now, has not been effective against other types of the disease. ATRA works by encouraging leukemia cells to mature and die naturally, but the researchers lead by Ar. Arthur Zelent say that the reason many AML patients do not respond to the treatment is because the genes that ATRA normally attacks are switched off by an enzyme called LSD1. The scientists discovered that using TCP to block this 'off switch' could reactivate these genes, making the cancer cells susceptible to ATRA.
The team has already joined forces with the University of Munster in Germany to start a Phase II clinical trial of the drug combination in AML patients. The authors also commented that both the retinoid ATRA and the antidepressant TCP are already available in the UK and off-patent, so these drugs should not be expensive for the health service.