Existing drugs can be used to treat blood cancer gene defects

Cancer occurs when there is a genetic defect which spreads as cells divide. Modern science has tools to detect those genetic genes and maybe we will be able to fix them some day.

Scientists at the University of Birmingham and Queen’s University Belfast have revealed that a defective gene normally found in blood cancers could be treated with available drugs.

In cancers called myelodysplastic syndromes blood cells do not form properly. This type of blood cancer is more common in older people

In cancers called myelodysplastic syndromes blood cells do not form properly. This type of blood cancer is more common in older people. Image credit: Ed Uthman via Wikimedia (CC BY 2.0)

Repurposing medications to treat blood cancer

PARP inhibitors, including olaparib and rucaparib, are used to treat ovarian, breast, prostate and pancreatic cancers. These illnesses have something in common – many patients have inherited a faulty BRCA1 or BRCA2 gene.

Scientists noticed that mutation of another gene SF3B1 produces similar effects – it stops normal DNA repair mechanisms and prevents it from making normal healthy copies of itself. SF3B1 mutations occur in blood cancers and scientists found that PARP inhibitors, specifically olaparib, could be used to address these gene mutations as well. PARP inhibitors stop DNA repair entirely and cause cancer cells to die.

The SF3B1 mutation is found in about 30% of blood cancers called myelodysplastic syndromes. In cases of this condition blood cells don’t form properly. These kinds of cancers usually occur in older people and are notoriously difficult to treat, because many therapies are quite harsh. Interestingly, SF3B1 mutation also occurs uveal melanoma or cancers of the eye, which are also extremely hard to treat. Scientists believe that tumours carrying SF3B1 gene mutation could be treated by PARP inhibitors. 

Future potential

Scientists hope that this discovery could lead to better survival rates, especially in cancers which have limited treatment options and Dr Kienan Savage, lead author of the study, said: “Our findings have clinical implications for the treatment of many cancers. We specifically focused on this genetic mutation as it is found in several difficult to treat leukaemias and other cancers, and it affects so many cancer patients. By deepening our understanding of this gene mutation, we have identified new ways of treating these cancers that could improve survival rates.”

PARP inhibitors can become a part of less-aggressive treatment in terms of adverse side effects. This would make this therapy more suitable for older and more frail people. Scientists now want to conduct clinical trials of PARP inhibitors with patients who have the SF3B1 mutation to see if they can stop their cancer from spreading. Testing should be aided by the fact that PARP inhibitors are already in use and their safety is well understood.

Cancer is very difficult to treat, but novel methods emerge all the time. Scientists are noticing that mortality statistics in cancer are getting better and hopefully PARP inhibitors will save many lives as well.

 

Source: University of Birmingham