Novel Suicide Gene Therapy Used to Treat Malignant Brain Tumors

Physicians and researchers in the Methodist Neurological Institute (NI) are studying the use of a novel combination of radiation and suicide gene therapy to treat typically stubborn malignant brain tumors.

This therapy, which combines radiation and gene therapy, has already proven successful in eradicating localized prostate cancer. Methodist is one of only two sites in the United States to offer this unique gene therapy clinical trial for patients with malignant gliomas, the most common form of brain tumor.

In the study, the common cold virus is used as a "cargo ship" to carry the herpes virus gene into the tumor. This gene agent, known as AdV-tk, is injected into the brain tumor during surgery. Following the procedure, study patients are given the drug Valtrex orally, which is the medication used to treat the herpes virus. When the drug kills the herpes, it also blasts the cancer cells, making them self-destruct. Study patients will also undergo radiation therapy and chemotherapy, if needed.

"Malignant gliomas are unique in their ability to grow uncontrollably and aggressively invade and destroy neighboring areas of the brain," said Dr. Pamela New, a neuro-oncologist and the principal investigator on this study at Methodist. "If this therapy can eliminate the spread of cancer in the brain and recognize and kill additional cancerous cells that may be lurking in the brain, then we can give our brain tumor patients freedom from this disease."

Malignant gliomas account for more than half of the more than 18,000 primary malignant brain tumors diagnosed each year in the United States. These tumors are the second-most common cause of cancer death in the 15 to 44 age group.

As a result of the success of the prostate study at Methodist, this treatment also will be applied to multiple cancer sites in the near future, including lung, pancreas, rectal, anal, and renal cell.

Researchers will follow a total of 24 study patients at the Methodist NI and Ohio State University for up to five years.

Source: Methodist Hospital, Houston