The confirmation of Ndrg1 protein induction in different cell lines. (A) HTE cells were incubated with different concentrations of NiCl2 (Ni), hypoxia, and 300 μM of CoCl2 (Co) for 20 hrs. (B) HOS and MCF-7, (C) PW and DU-145 cells were incubated with 500 μM of NiCl2 (nickel), hypoxia, and 300 μM of CoCl2 (cobalt) for 20 hrs. Western blot analyses were done as described in 'Methods' section. The membranes were first incubated with anti-Ndrg1 antibody (top panels), then stripped, and rehybridized with anti-actin antibody (bottom panels) to show loading.