title: Inhibition of tumor necrosis factor-α enhances apoptosis induced by nuclear factor-κB inhibition in leukemia cells.
abstract: Inhibition of nuclear factor-κB (NF-κB) results in antitumor activity in leukemia cells, and may be a potential therapeutic strategy for the treatment of leukemia. However, a significant limitation of NF-κB inhibition in the treatment of leukemia is the low efficiency of this technique. NF-κB inhibitor treatment induces apoptosis in leukemia cells; however, it additionally causes inflammatory molecules to induce increased sensitivity of healthy hematopoietic cells to cell death signals, therefore limiting its clinical applications. Tumor necrosis factor-α (TNF-α) is a key regulator of inflammation, and induces a variety of actions in leukemic and healthy hematopoietic cells. TNF-α induces NF-κB-dependent and -independent survival signals, promoting the proliferation of leukemia cells. However, in healthy hematopoietic cells, TNF-α induces death signaling, an effect which is enhanced by the inhibition of NF-κB. Based on these observations, the present study hypothesized that inhibition of TNF-α signaling may be able to protect healthy hematopoietic cells and other tissue cells, while increasing the anti-leukemia effects of NF-κB inhibition on leukemia cells. The role and underlying molecular mechanisms of TNF-α inhibition in the regulation of NF-κB inhibition-induced apoptosis in leukemia cells was therefore investigated in the present study. The results indicated that inhibition of TNF-α enhanced NF-κB inhibition-induced apoptosis in leukemia cells. It was also revealed that protein kinase B was significant in the regulation of TNF-α and NF-κB inhibition-induced apoptosis. During this process, intrinsic apoptotic pathways were activated. A combination of NF-κB and TNF-α inhibition may be a potential specific and effective novel therapeutic strategy for the treatment of leukemia.
authors.affiliation: Central Laboratory, The First Hospital of Lanzhou University, Lanzhou, Gansu 730000, P.R. China.
authors.forename: Qiao-Mei
authors.initials: QM
authors.lastname: Dong
authors.affiliation: Central Laboratory, The First Hospital of Lanzhou University, Lanzhou, Gansu 730000, P.R. China.
authors.forename: Chun
authors.initials: C
authors.lastname: Ling
authors.affiliation: Central Laboratory, The First Hospital of Lanzhou University, Lanzhou, Gansu 730000, P.R. China.
authors.forename: Xuan
authors.initials: X
authors.lastname: Chen
authors.affiliation: Central Laboratory, The First Hospital of Lanzhou University, Lanzhou, Gansu 730000, P.R. China.
authors.forename: L I
authors.initials: LI
authors.lastname: Zhao
keywords: apoptosis; caspase 9; leukemia; molecular mechanism; nuclear factor-κB inhibition; protein kinase B; tumor necrosis factor α