MPO and glioblastoma: The avidin-biotin peroxidase technique was used to detect various markers, such as CD3 (T-cells), CD8 (cytotoxic T-cells), CD68 (macrophages), myeloperoxidase (MPO), heat shock protein 70 (HSP70), and caspase-3, in glioblastoma tissues treated with NPs and radiotherapy.