Western blotting of PDK1. NB4 and THP-1 were cultured in the same condition as cell proliferation assay for 24 hours. PDK1 was abundantly expressed in NB4 even under normoxia, culture under hypoxia did not augment the expression of PDK1 in NB4. Expression of PDK1 was augmented by hypoxia in THP-1. Top, PDK1; bottom, β-actin. H: under hypoxia, N: under normoxia.