Rotavirus vaccines kill cancer cells

The team headed by Aurelian Marabelle discovered in mice that commercially available vaccines against rotavirus – which causes diarrhea in children – have cancer-killing properties and boost the power of PD-1 and CTLA-4 checkpoint inhibitors. As the vaccines are available and have established safety records, the researchers suggest to use them to prime the immune system to be more responsive to cancer immunotherapy.

Tala Shekarian and colleagues found that the approved attenuated rotavirus vaccines Rotateq and Rotarix –  induced cell death in neuroblastoma and breast cancer cell cultures by activating NF-κB, without harming healthy human fibroblasts or breast tissue cells. Further experiments showed that injecting weakened or inactive strains of rotavirus boosted the efficacy of anti-PD-L1 and anti-CTLA-4 therapy in mouse models of lymphoma and neuroblastoma, partly by activating an RNA receptor named RIG-I. The authors believe that weakened strains of rotavirus could be used to mitigate treatment resistance in patients with cancer, especially in pediatric populations with malignancies such as neuroblastoma.