Identification of ANXA1 as A Novel Upstream Negative Regulator of Notch1 Function in AML

ABSTRACT: Abnormal Notch1 expression has an important role in tumorigenesis. However, upstream control mechanisms for Notch1 are still insufficiently understood. Acute myeloid leukemia (AML) is one of the most common and lethal blood malignancies with limited possibilities for treatment. Thus, new therapeutic targets are urgently needed to improve current ineffective therapies. Herein, we found high Annexin A1 (ANXA1) expression was corelated with hyperproliferation of AML cells, and then we identified ANXA1 as a novel negative regulator of Notch1 function in AML. Mechanistically, ANXA1 directly bound to the intracellular domain of Notch1 (NICD) to target this tumor suppressor for degradation. Furthermore, NICD executed its tumor suppressive function through activation of the p15 promoter. Thus, ablation of the Notch1-p15-mediated tumor suppression by ANXA1 provided a novel mechanism of AML proliferation. In human AML patients, we discovered a mutual exclusive relation existed between ANXA1 and Notch1/p15, corroborating our mechanistic discovery. On the basis of these results, we reasonably speculate that targeting ANXA1 would provide an effective approach for treatment of AML. In support of this new therapeutic paradigm, we provided proof-of-concept data by antagonizing ANXA1 using NICD inhibitory peptides.

ORGANISM(S): Homo Sapiens

SUBMITTER: Caiyun Fu  

PROVIDER: PXD056593 | iProX | Thu Oct 03 00:00:00 BST 2024

REPOSITORIES: iProX