PARP1 and head and neck squamous cell carcinoma: We extended our observations of the impact of the PARP inhibitors olaparib and talazoparib in radiosensitising HPV-negative HNSCC 3D spheroids by examining the effects in response to proton beam therapy, which is a precision-targeted modality that is increasingly being utilised for the treatment of HNSCC patients (25, 26).