Researchers from the University of York in the UK have discovered a potential new treatment option for patients with early-stage prostate cancer – low-temperature plasmas.
The study, published in the British Journal of Cancer, seeks to address the current inadequacy of long-term treatment for prostate cancer, despite the continual improvements that have been made to methods of treatment in recent years.
At present, patients who develop early stage organ-confined tumors can be treated with a focal therapy, such as cryotherapy or radiotherapy.
“However, around a third of patients will experience recurrence of their disease following radiotherapy,” explains study co-author Adam Hirst. “This may be due to the inherent radio-resistance of a small fraction of the tumor – the cancer stem-like cells. Furthermore, numerous side effects are often experienced following treatment.”
According to the American Cancer Society (ACS), prostate cancer is the second-most common cancer in American men and the second leading cause of cancer death among this group. Around 1 in 7 will be diagnosed with the disease during their lifetime, at an average age of 66.
“In recent years, the rapidly advancing field of low-temperature atmospheric pressure plasmas has shown considerable promise for future translational biomedical applications,” write the study authors, “including cancer therapy, through the generation of reactive oxygen and nitrogen species.”
Low-temperature plasmas are formed when a high electric field is applied across a gas via an electrode, breaking down the gas. As the plasma is formed, a unique reactive environment is formed that contains high concentrations of reactive oxygen and nitrogen species.
The plasmas are subsequently used to transfer reactive oxygen and nitrogen species to a target, leading to oxidative damage and cell death that differs from the kind caused by other forms of therapy.
While other therapies cause apoptosis, prompting cells to die through natural mechanisms that cells can eventually become resistant to, low-temperature plasma breaks up cells and causes necrosis. In necrosis, cell death occurs through the rupturing of cell membranes.
The researchers used tissue samples from a single patient in order to take both healthy prostate cells and prostate cancer cells, allowing for a direct comparison of the effectiveness of the treatment.
“Through this research we have found that [low-temperature plasmas] induce high levels of DNA damage, which led in turn to a substantial reduction in colony-forming ability, and ultimately necrotic cell death,” states Hirst.
As well as being effective at killing cancer cells, the use of low-temperature plasmas could also be a more cost-effective way of treating organ-confined prostate cancer in comparison with current forms of radiotherapy and photodynamic therapy.
“Using clinically relevant, close-to-patient samples, we have presented the first experimental evidence promoting the potential of [low-temperature plasma] as a future focal cancer therapy treatment for patients with early stage prostate cancer,” Hirst concludes.
The researchers will now look at testing the application of low-temperature plasmas on three-dimensional replica tumors in order to assess the precision of plasma application.
“We believe that with appropriate imaging techniques to facilitate accurate tumor targeting and spare normal tissues, the multifaceted action of [low-temperature plasma] will provide advantages over other focal therapies,” state the authors.
The team estimates that if all trials are successful, low-temperature plasma could be used to treat cancer patients in 15 years time.
Recently, Medical News Today reported on a study in which an international consortium of scientists reveals the genetic root of prostate cancers in individual men. Their discovery demonstrates that tumors share common gene faults that could offer new targets for treatment.