MYC and cancer: The potent anti-cancer efficacy of H5CmTERT-Ad-driven oncolytic adenoviruses could be attributed to the following factors: (1) insertion of additional c-Myc-binding sites enhanced the transcriptional activity in glioblastoma cells because c-Myc proto-oncogene expression has been found to positively correlate with the grade of malignancy in glioblastoma44 and (2) insertion of HREs augmented the promoter activity under hypoxic conditions45–47.