Under hypoxia, some cells are irreversibly injured and die, whereas others can adapt to the
stress and survive. The molecular and genetic basis underlying cellular sensitivity to hypoxic
injury is unclear. Here we have selected death-resistant cells by repeated episodes of
hypoxia. The selected cells are cross-resistant to apoptosis induced by staurosporine, azide,
and cisplatin. These cells up-regulate Bcl-X L, an anti-apoptotic protein. Bcl-X L interacts
with the pro-apoptotic molecule Bax and abrogates its toxicity in mitochondria, resulting in …