To date, attenuation by gene-inactivating deletions has been widely applied to HSV-1, but this strategy can limit the efficacy of oHSVs since it can compromise the virulence also in tumour cells54, and affect the viral ability to escape host’s antiviral immune pathways (e.g. cGAS/STING axis)55,56. This evidence concerns the gene STING1 and neoplasm.