IDUA and neuroblastoma: The pro-apoptotic effects of AZD7762 and etoposide on their sensitive NB subtypes were verified using the terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL) assay, which demonstrated that the proportion of apoptotic cells was significantly augmented in the AZD7762-treated MPS-I and etoposide-treated MPS-II groups (Figure 9 E and F).