Mcl-1 expression and JNK activation induces a threshold for apoptosis in Bcl-xL-overexpressing hematopoietic cells.
Oncotarget 2017;
8:11042-11052. [PMID:
28038464 PMCID:
PMC5355244 DOI:
10.18632/oncotarget.14223]
[Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 12/20/2016] [Indexed: 02/05/2023] Open
Abstract
The regulation of Mcl-1 expression is necessary for the induction of cancer cell apoptosis by ABTs such as ABT-737, ABT-263 and ABT-199. However, the reduction in Mcl-1 expression is not sufficient for initiating cell death in hematopoietic cancer cells with high Bcl-xL expression. Here, we demonstrate that 2-deoxyglucose (2-DG) enhanced the effect of ABT-199 to induce cell apoptosis in hematologic malignancies with up-regulated Bcl-xL expression. Our study revealed that 2-DG could decrease glucose-dependent and Akt-independent Mcl-1 expression, which is mediated by the mechanistic target of rapamycin complex 1 (mTORC1) pathway. Moreover, the combination of 2-DG and ABT-199 triggered c-Jun NH2-terminal kinase (JNK) phosphorylation and subsequent Bcl-xL degradation, whereas 2-DG and ABT-199 alone had little effect on JNK activation. Therefore, the combination of 2-DG and ABT-199 initiated cell death through the reduction of Mcl-1 expression and JNK activation. Our study could provide a clinical theoretical basis for the use of ABT-199 in hematologic malignancies with excessive Bcl-xL expression.
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