The scientists from the Trinity Translational Medicine Institute at St James’s Hospital Dublin, in collaboration with the Cancer Stem Cell Group, Coombe Hospital, Dublin, found that lung cancer cells that have high levels of ALDH activity, a recently identified marker of cancer stem cells became resistant to chemotherapy. This induces the growth and expansion of a drug-resistant population of lung cancer cells, allowing the cancer cells to survive the effects of treatment.
These findings may help explain why a large number of lung cancer patients receiving this type of chemotherapy eventually relapse resulting in progression of their disease.
The FDA-approved alcohol aversion drug Disulfiram (Antabuse), which has been used to treat alcohol addiction for over sixty years, works against ALDH by restricting its activity.
Disulfiram is an already approved drug with well-tolerated side effects which can be taken orally. Its potential use may give chemotherapeutic drugs such as cisplatinin the treatment of resistant lung tumours.
Upon alcohol consumption, it prevents the body from metabolising alcohol and makes the person feel sick. When it comes to cancer cells, the drug was found to be effective in inhibiting the activity of ALDH, which resulted in decreased tumour cell growth and increased killing of lung cancer stem cells. The research team found that the alcohol aversion drug Disulfiram in combination with chemotherapy was significantly more effective in killing drug-resistant lung cancer stem cells compared to treatment with the chemotherapy alone.
Dr Martin Barr, Adjunct Assistant Professor and a lead investigator in the Thoracic Oncology Research Group, St James’s Hospital and Trinity said: “Disulfiram is an already approved drug with well-tolerated side effects which can be taken orally. Its potential use may give chemotherapeutic drugs such as cisplatin, a new lease of life in the treatment of resistant lung tumours. We believe that our research findings show that this is a really important option that warrants further investigation and clinical testing. “
An alternative approach to seeking new drug treatments for cancer is not to start with molecular targets, but to assess those drugs approved for other therapeutic uses which show some evidence of anti-cancer activity. This is the field of drug repurposing in oncology and there is now an increasing interest in the use of non-cancer drugs as anti-cancer therapeutics.
This is the field of drug repurposing in oncology and there is now an increasing interest in the use of non-cancer drugs as anti-cancer therapeutics.
“The development of novel anti-cancer drugs against various malignant tumours is both time-consuming and expensive and involves pre-clinical and clinical testing. Finding new uses for existing drugs, otherwise known as ‘repurposing’, may allow for new uses of an old drug that may lead to the discovery of new treatments. Such repurposing is a proven shortcut between the research laboratory and the clinic,” said Dr Lauren MacDonagh who carried out this study as part of her PhD at Trinity College Dublin.
