By Sara Bondell - June 02, 2023
A modified form of the herpes virus was approved by the U.S. Food and Drug Administration in 2015 as a standard treatment for melanoma.
Talimogene laherparepvec, or T-VEC, is a modified form of the herpes simplex 1 virus that is injected directly into a tumor. It causes cancer cells to burst and activates the immune system to attack tumors.
Researchers at Moffitt Cancer Center are now investigating if T-VEC can target triple-negative breast cancer.
“While some features of triple-negative breast cancer make the tumor more aggressive, those same features can make the tumor more susceptible to oncolytic viruses. Oncolytic viruses like tumors that are rapidly dividing because then it can recruit more cell machinery to make more virus when they’re activated,” said Dr. Hatem Soliman, a breast oncologist.
A previous Moffitt study found triple-negative breast cancer patients whose tumors were injected with T-VEC while undergoing chemotherapy were more likely to have no viable cancer left in their breasts or lymph nodes after the tissue was surgically removed.
A new study investigated if analyzing a tumor’s genetic material could better predict which triple-negative breast cancer patients would benefit from T-VEC and chemotherapy prior to surgery. The data was presented at the 2023 American Society of Clinical Oncology Annual Meeting.
“We were able to utilize a lot of our technology and research capabilities to analyze samples from these tumors prior to treatment in order to extract RNA and DNA genetic material and sequence this information in order to understand how genes were being turned on or off within the tumors, and also potentially what mutations were harbored within the tumors,” said Soliman, the lead trial investigator.
The study compared women who responded well to the treatment with those who did not, hoping to identify certain genetic markers that predict response and find clues to treatment resistance. Researchers were ultimately able to identify several genes that were upregulated in women who had a complete response, as well as a gene called EIF2A that was associated with a poorer response to therapy. This could help physicians handpick patients who would benefit from the T-VEC and chemotherapy combination therapy in the future.
“There are some genetic findings here that are interesting to look at. We want to continue to pursue this research because it appears to be something promising,” Soliman said. “We are hoping the work we have published serves as a foundation for building up ways to investigate oncolytic viruses in the treatment of triple-negative breast cancer.”