Tetrahydrobenzimidazole TMQ0153 triggers apoptosis, autophagy and necroptosis crosstalk in chronic myeloid leukemia

Sungmi Song,Christo Christov,Déborah Gérard,Jung Weon Lee,Hyejin Kim,Aloran Mazumder,Mario Dicato,Dong-Wook Kim,Ludmila Ermolenko,Jin-Young Lee,Marc Diederich,Heeju Ryu,Ali Al-Mourabit,Claudia Cerella,Barbora Orlikova-Boyer,Seungwon Ji,Michael Schnekenburger

doi:10.1038/s41419-020-2304-8

Abstract

By comparing imatinib-sensitive and -resistant chronic myeloid leukemia (CML) cell models, we investigated the molecular mechanisms by which tetrahydrobenzimidazole derivative TMQ0153 triggered caspase-dependent apoptosis at low concentrations accompanied by loss of mitochondrial membrane potential (MMP) and increase of cytosolic free Ca2+ levels. Interestingly, at higher concentrations, TMQ0153 induced necroptotic cell death with accumulation of ROS, both preventable by N-acetyl-L-cysteine (NAC) pretreatment. At necroptosis-inducing concentrations, we observed increased ROS and decreased ATP and GSH levels, concomitant with protective autophagy induction. Inhibitors such as bafilomycin A1 (baf-A1) and siRNA against beclin 1 abrogated autophagy, sensitized CML cells against TMQ0153 and enhanced necroptotic cell death. Importantly, TMQ153-induced necrosis led to cell surface exposure of calreticulin (CRT) and ERp57 as well as the release of extracellular ATP and high mobility group box (HMGB1) demonstrating the capacity of this compound to release immunogenic cell death (ICD) markers. We validated the anti-cancer potential of TMQ0153 by in vivo inhibition of K562 microtumor formation in zebrafish. Taken together, our findings provide evidence that cellular stress and redox modulation by TMQ0153 concentration-dependently leads to different cell death modalities including controlled necrosis in CML cell models.

Highlights

Imatinib kills leukemic cells essentially via apoptosis but triggers primary or secondary resistance in approximately 20–30% of patients[1]
Our results show that the expression level of NADPH oxidases (NOX) regulator cytochrome b-245 heavy chain (CYBB) was more elevated in chronic myeloid leukemia (CML) patients compared to healthy donors (Supplementary Fig. 9) leading to an increased NOX activity and an increase in reactive oxygen species (ROS) production[30]
We attempted to address the interplay between apoptosis, autophagy, and necroptosis in CML cell models, by using an experimental prooxidant therapeutic approach with the cytotoxic synthetic hydroquinone derivative TMQ0153 aiming to disrupt oxidative and metabolic stress homeostasis

Summary

Introduction

Imatinib kills leukemic cells essentially via apoptosis but triggers primary or secondary resistance in approximately 20–30% of patients[1]. Second-generation tyrosine kinase inhibitors (TKIs) such as dasatinib and nilotinib reactivate apoptotic cell death induction[2,3] in patients with imatinib resistance, de novo resistance against these TKIs was reported[4]. Transformation of leukemic cells by Bcr-Abl is associated with metabolic alterations and increased reactive oxygen species (ROS) generation. Koptyra et al showed that Bcr-Abl kinase stimulates ROS that cause oxidative DNA damage that results in the mutation of the kinase domain, leading to imatinib resistance. Landry et al.[5] published that NADPH oxidase (Nox) activity affects intracellular ROS levels in Bcr-Abl positive cells, enhancing

Methods

Results

Conclusion