No regulatory effect of these different oxygenation conditions on GAPDH expression was shown by semiquantitative RT-PCR in the Hep-1-6 mouse hepatoma and in Hep-3-B and HepG2 human hepato-cellular carcinoma cell lines (Fig. 1A) as well as in human lung adenocarcinoma epithelial cell line (A-549) and both HT-29 and HCT-116 colon cancer cell lines (Fig. 1C). Here, GAPDH is linked to malignant colon neoplasm.