Recently, we demonstrated that metastatic cancer cells have an increased level and activity of DNA-PKcs, the catalytic subunit of DNA-dependent protein kinase (DNA-PK), compared with their primary cells [14], and An et al. reported that DNA-PKcs regulates the stability of c-Myc through the Akt/GSK3β/c-Myc ubiquitination signal pathway [15]. Here, MYC is linked to metastatic malignant neoplasm.