Language

English

Publication Date

8-14-2025

Journal

Blood

DOI

10.1182/blood.2025028938

PMID

40359431

Abstract

Insufficient eradication of cancer cells and survival of drug tolerant clones are major relapse driving forces. Underlying molecular mechanisms comprise activated prosurvival and antiapoptotic signaling, leading to insufficient apoptosis and drug resistance. The identification of programmed cell death pathways alternative to apoptosis opens up possibilities to antagonize apoptosis escape routes. We have earlier shown that acute lymphoblastic leukemia (ALL) harbors a distinct propensity to undergo cell death by receptor-interacting protein kinase 1 (RIPK1)-dependent necroptosis, activated by small-molecule second mitochondria-derived activators of caspase (SMAC) mimetics. Despite demonstrated safety and tolerability of SMAC mimetics in clinical trials, their efficacy as single agent seems still limited, highlighting the need for combinatorial treatments. Here, we investigate so far unexplored regulatory mechanisms of necroptosis and identify targets for interference to augment the necroptotic antileukemia response. Ex vivo drug response profiling in a model of the bone marrow microenvironment reveals powerful synergy of necroptosis induction with histone deacetylase (HDAC) inhibition. Subsequent transcriptome analysis and functional in vivo CRISPR screening identify gene regulatory circuitries through the master transcription regulators specificity protein 1 (SP1), p300, and HDAC2 to drive necroptosis. Although deletion of SP1 or p300 confers resistance to necroptosis, loss of HDAC2 sensitizes cells to RIPK1-dependent cell death by SMAC mimetics. Consequently, our data inform strong in vivo antileukemic activity of combinatorial necroptosis induction and HDAC inhibition in patient-derived human leukemia models. Thus, transcriptional dependency of necroptosis activation is a key regulatory mechanism that identifies novel targets for interference, pointing out a strategy to exploit alternative nonapoptotic cell death pathways to eradicate resistant disease.

Keywords

Humans, Precursor Cell Lymphoblastic Leukemia-Lymphoma, Necroptosis, Animals, Mice, Receptor-Interacting Protein Serine-Threonine Kinases, Sp1 Transcription Factor, Gene Expression Regulation, Leukemic, Histone Deacetylase Inhibitors, Cell Line, Tumor, Transcription, Genetic

Published Open-Access

yes

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.