Combining suicide gene therapy and chemo combo kills prostate cancer cells - Results of a long-term clinical trial have demonstrated that combining chemotherapy with a treatment known as "suicide gene therapy," can successfully kill prostate tumor cells.
In the study published in the Journal of Radiation Oncology, researchers from the Houston Methodist Hospital, U.S., compared two groups of patients and report high five-year overall survival rates of 97 percent and 94 percent, respectively.
Between 1999 and 2003, 36 prostate cancer patients participated in the phase II clinical trial, and were split into two groups.
One group with cancer cells confined to the prostate, assigned Arm A, received only radiotherapy while the other with a more aggressive prostate cancer, Arm B, received both radiation and hormonal therapies.
The patients in Arm A received the experimental gene therapy twice during the study, whereas the Arm B group received the treatment thrice.
Senior study author E. Brian Butler said we used an adenovirus, similar to the one that causes the common cold, to carry the therapy agent - a herpes virus gene that produces the enzyme thymidine kinase, or TK -directly into the tumor cells.
Butler further added that once the herpes virus gene was delivered and it began manufacturing TK, patients were given a commonly used anti-herpes drug, valacyclovir. The combination attacked the herpes DNA, and the TK-producing tumor cells self-destructed, which is why the procedure is called 'suicide gene therapy.'