A new technique in Gene Therapy Kills Prostate Tumor Cells

Results from a long-term clinical trial conducted by cancer researchers at Houston Methodist Hospital show that combining radiation treatment with “suicide gene therapy”, a technique in which prostate cancer cells are genetically modified so they signal a patient’s immune system to attack them, provides a safe and effective one-two punch against the disease. The research team concluded that survival rate was 5-20 percent higher compared to now used medical procedures for treatment. Once the herpes virus gene is delivered to the patient, it starts producing thymidine kinase. The technique causes the tumour cells in the body to self-destruct, giving it the name “suicide gene therapy”.

A phase III patient trial, which is the final efficacy and safety evaluation for in-situ immunomodulatory gene therapy before it gets the FDA approval, is already in the pipeline. Those presenting with less severe cases of cancer were only administered radiotherapy, while those with more advanced cancers were also given hormonal therapy in addition to radiotherapy. While severe cases of prostate cancer were offered suicide gene therapy thrice, the less severe prostate cancer patients were given the therapy twice.

The 62 patients in both arms who completed the clinical trial had remarkably high five-year freedom from failure rates, meaning no indication by biochemical testing of cancer recurrence, of 94 per cent and 91 per cent, respectively. Although there was no control group in this study, the researchers said the results showed a five to 20% improvement on previous studies of prostate cancer treatment. For severe prostate cancer, the survival rate was 94 percent. The sample group was divided into two different subsections: one consisting of patients whose cancer diagnosis was considered more severe, and another whose cancer was considered less severe.

High success rates were recorded even in the absence of androgen deprivation therapy, which is commonly employed so as to stop prostate tumors for becoming more widespread and aggressive. That DNA material was transported inside the genes by employing adenoviruses, just like the ones that transmit conditions such as bronchitis, conjunctivitis, pneumonia or the common cold.

Researchers at Houston Methodist Hospital have come up with a new treatment for prostate cancer which they claim could successfully and safely kills prostate tumor cells.

For the study, the researchers modified a gene, which is then delivered into the tumor cells using a virus vector, or a virus is implanted with the gene.

The findings appeared online in the Journal of Radiation Oncology (JRO). In the United Kingdom alone, around 41,000 individuals every year are diagnosed with prostate cancer. 24 months after the treatment was fully administrated prostate biopsies were performed. The scientists added that this result was extremely pleasing, particularly considering that the patients enrolled in the study were deemed incurable by other physicians, according to Bin Ten, the lead author of the study.