An experimental gene therapy has been shown to eradicate advance prostate cancer — offering a promising new approach that could one day lead to novel treatments for life-threatening tumors.

Even with the best available treatments, most patients with untreatable advanced cancer — known as metastatic, hormone-refractory prostate cancer — live only two to three years.

But researchers at Virginia Commonwealth University have developed a unique approach that uses microscopic gas bubbles to deliver a viral gene therapy directly to the cancer, in combination with an experimental drug that targets a specific gene driving the cancer's growth.

The combo therapy was able to destroy primary and metastatic prostate cancer tumors in pre-clinical laboratory tests that could pave the way for animal studies and eventual trials in human cancer patients.

"We are at a point in our research where we have validated the efficacy of this combination treatment approach in preclinical animal models, and we now need to define its safety through toxicology and pharmacology studies," said lead researcher Paul B. Fisher, chairman of VCU School of Medicine's Department of Human and Molecular Genetics and director of the VCU Institute of Molecular Medicine.

"We are hopeful that this research will culminate in the development of a phase 1 clinical trial that will test the safety of this novel approach and potentially lead to an effective new therapy for advanced prostate cancer."

The new treatment, detailed in the journal Oncotarget, uses a novel "cancer terminator virus" (CTV), which delivers a tumor-killing agent.

In laboratory tests, the researchers found CTV, when combined with an experimental drug known as BI-97D6, effectively killed prostate tumors without harming health tissues.

"This approach holds promise for the treatment of many different cancers," said Fisher. "Our team is collaborating with researchers … to move this research forward."