HuH - 7 (human HCC), HepG2 (human hepatocellular blastoma), 293T (human
embryonic kidney fibroblast), HeLa (human cervical cancer cells), NIH 3T3 (murine fibroblast), and HCT116 (human colon cancer) and its derived cell line HCT116 p21 − / − (kindly provided by Dr. B. Vogelstein, Howard Hughes Medical Institute, Chevy Chase and the Sydney Kimmel Comprehensive Cancer Center of the Johns Hopkins University School of Medicine, Baltimore, MD; ref.