A study published by the online medical publication PLOS ONE earlier this month has shown that a drug traditionally used to treat alcoholism can have a clinical benefit for mesothelioma patients as well. Curiously enough, this drug may suppress tumor growth and make mesothelioma cells more responsive to chemotherapy and radiation treatment.
Disulfiram, or Antabuse as it’s more commonly known, has been used for decades in the treatment of alcoholism. It works by interfering with alcohol-processing enzymes in the body, making those who take it essentially unable to stomach alcohol.
Only more recently has it shown potential as an anticancer drug. A clinical trial completed in 2009 by the Hadassah Medical Organization in Israel tested the efficacy of disulfiram in combination with chemotherapy in lung cancer patients, showing a clinical benefit.
“Several studies have shown that [disulfiram] and its metabolites can potentiate the effects of some anticancer drugs,” reported the study by PLOS. It was further shown that “proof-of-concept studies reveal, for the first time, [mesothelioma] inhibitory properties of [disulfiram].”
Suppressing Mesothelioma Growth
Disulfiram must be binded with a copper compound to exhibit results as an anticancer drug. Used this way, disulfiram may inhibit mesothelioma growth and interrupt signaling between mesothelioma cells. However, further research is required to determine exactly how this drug interacts with mesothelioma cells.
This new study shows the drug can induce apoptosis in pleural mesothelioma cells. Apoptosis is the process of cellular death that healthy cells undergo. Cancer cells typically do not submit to apoptosis, resulting in the uncontrollable growth of mesothelioma tumors.
“Consistent with emerging anti-cancer potential of [disulfiram], our current studies revealed that [disulfiram] inhibits growth of a number of [pleural mesothelioma] cells,” the authors of the study said.
It is also believed the drug may work by preventing the growth of new blood vessels in mesothelioma tumors, thereby inhibiting the growth and spread of the disease. The growth of blood vessels in tumors, known as angiogenesis, is a key biological factor in the progression of cancers.
Dr. Arun Rishi of Karmanos Cancer Institute, one of the studies co-authors, expressed optimism for exploring this treatment option in mesothelioma patients.
” The clinical trials for [disulfiram] in [mesothelioma] patients are a logical next step,” said Dr. Rishi. “We have an on-going collaboration with MPM expert and co-author Dr. Harvey Pass to explore and pursue this issue.”
Making Chemotherapy and Radiation More Effective
One of the greatest advantages to using disulfiram for mesothelioma treatment is that researchers already know it is well-tolerated in humans. When new drugs for cancer treatment are being tested, the first step after animal trials is to determine the acceptable levels of toxicity.
Chemotherapy drugs, for instance, are extremely toxic substances even in low doses and may not offer a benefit to mesothelioma patients if it affects their overall health too much.
Disulfiram, however, has virtually no toxicity levels–meaning it could be used as part of a multimodal approach to make chemotherapy and radiation more effective. This would be a welcome development in chemotherapy for mesothelioma.
The only FDA-approved treatment for mesothelioma, Alimta and cisplatin, wasn’t approved until barely a decade ago. Although progress is being made, chemotherapy treatments for mesothelioma patients are somewhat ineffectual in comparison to treatment for other cancers.
While survival rates vary with factors such as age and the stage of disease, chemotherapy alone has only shown a survival benefit of several months. Diseases such as prostate cancer are much more receptive to chemotherapy. Therefore, mesothelioma patients, especially those who aren’t able to have surgery, may seriously benefit from the addition of disulfiram in their treatment plan if it increases the efficacy of chemotherapy.
“Our studies are but a first step, and I am certain that anti-[mesothelioma] properties and survival benefits will be explored henceforth,” said Dr. Rishi.
Although more is yet to be learned about disulfiram in relation to mesothelioma treatment, the drug’s relatively low risk may make it a viable option for patients in the near future.