Abstract
A modified oncolytic vaccinia virus helps kill pancreatic tumor cells and makes them more vulnerable to immunotherapy in an animal model, shows research. Oncolytic viruses that are designed to attack tumor cells are a promising therapeutic option for pancreatic cancer, but reliable delivery to the tumor cells has been problematic in the past. This is particularly true for inaccessible or metastatic cancers, where treatment cannot always be injected directly into the tumor.
Yaohe Wang, M.D., Ph.D., a professor at the Barts Cancer Centre at Queen Mary, and his team engineered an oncolytic vaccinia virus to spread more easily between cancer cells in a tumor and between different tumors. They also ‘armed' the virus with interleukin-21 which can help activate immune T cells to target the cancer.
The researchers tested the efficacy of the modified virus in mouse and Syrian hamster models of pancreatic cancer. As reported in the Journal for ImmunoTherapy of Cancer, treatment of the animals with a combination of the oncolytic virus, the checkpoint inhibitor, and a drug (PI3Kδ inhibitor) that stops white blood cells in the immune system from destroying the therapeutic virus led to extended survival.
Addition of interleukin-21 also seemed to make the tumors more susceptible to treatment with an immune checkpoint inhibitor.
The team now hopes to progress the research to Phase I clinical trials to assess the efficacy of this treatment in pancreatic cancer patients.
