Vitamin A May Improve Prostate Cancer Response To Treatment
A new research conducted by the scientists at the University of York have shown a link between prostate cancer and vitamin A. Professor Norman Maitland and his team, found that a prostate specific gene expression can be controlled by retinoic acid, a derivative of vitamin A.
This discovery was published in the scientific journal Nucleic Acids Research and shows the possibility of testing if administration of retinoic acid in prostate cancer patients can force prostatic malignant stem cells to develop in more specialized cells. The process according to which stem cells develop in more specialized cells is known as differentiation and is useful in cancer treatment because may produce death of cancerous cells or make malignant cells more susceptible to chemotherapy.
All-trans retinoic acid therapy (ATRA) is already used in another form of cancer acute promyelocytic leukaemia (APL) and has been hugely successful in improving survival rates from 0% to 80%.
Approximately 41,000 men are diagnosed with prostate cancer every year in the UK, and although around 80% survive for five years or more, 10,000 men die annually.
Professor Maitland, Director of the YCR Cancer Research Unit in the Department of Biology, said: “It has been known for many years that low vitamin A in samples of blood is associated with prostate cancer, but nobody knew the mechanisms involved. We have revealed a functional biological link between retinoic receptor expression and our laboratory models of prostate cancers.
In this study, scientists investigated a gene called the prostate transglutaminase (TGP). TGP gene is one of the most prostate-specific genes known from the 28,000 in the human genome and they demonstrated that the TGP gene is controlled by the retinoic acid signalling pathway. They observed that when retinoic acid enters into prostate cancer cell, it binds to one of the three receptors that are located in the nucleus of the cell. After this binding, a sequence of molecular events are triggered inside cell nucleus which results in the activation or inhibition of TGP gene. Scientists also demonstrated that this situation is applied to a great number of other genes, gens that are telling the cell how to behave (to divide for example).
In a separate review article published in Nature Reviews Urology, Professor Maitland argues that differentiation therapies have previously been misused in cancer treatments, but that used in lower doses, they could be a realistic treatment option.
“Oncologists have been using agents such as retinoic acid as toxins. What we need to do is use them at lower doses so that they change the properties of the susceptible cells. However, they may affect normal stem cells and some cells may react unpredictably, so we need to investigate what happens before we try the treatment on patients. This will now form part of our experimental approach in York.”, Professor Maitland added.