Mannose metabolism inhibition sensitizes acute myeloid leukaemia cells to therapy by driving ferroptotic cell death

Unraveling lipid metabolism for acute myeloid leukemia therapy

PURPOSE OF REVIEW

The aim of this review is to highlight the importance of lipids' intricate and interwoven role in mediating diverse acute myeloid leukemia (AML) processes, as well as potentially novel lipid targeting strategies. This review will focus on new studies of lipid metabolism in human leukemia, particularly highlighting work in leukemic stem cells (LSCs), where lipids were assessed directly as a metabolite.

RECENT FINDINGS

Lipid metabolism is essential to support LSC function and AML survival through diverse mechanisms including supporting energy production, membrane composition, signaling pathways, and ferroptosis. Recent work has highlighted the role of lipid rewiring in metabolic plasticity which can underlie therapy response, the impact of cellular and genetic heterogeneity in AML on lipid metabolism, and the discovery of noncanonical roles of lipid related proteins in AML.

SUMMARY

Recent findings around lipid metabolism clearly demonstrates their importance to our understanding and therapeutic targeting of AML. We have only begun to unravel the regulation and utilization of lipids in this disease. Further, understanding the layered dynamics of lipid homeostasis could provide novel opportunities to target lipid metabolism in AML and LSCs with the potential of improving outcomes for patients with AML.

Mannose metabolism reshapes T cell differentiation to enhance anti-tumor immunity

Cellular metabolic status profoundly influences T cell differentiation, persistence, and anti-tumor efficacy. Our single-cell metabolic analyses of T cells reveal that diminished mannose metabolism is a prominent feature of T cell dysfunction. Conversely, experimental augmentation/restoration of mannose metabolism in adoptively transferred T cells via D-mannose supplementation enhances anti-tumor activity and restricts exhaustion differentiation both in vitro and in vivo. Mechanistically, D-mannose treatment induces intracellular metabolic programming and increases the O-GlcNAc transferase (OGT)-mediated O-GlcNAcylation of β-catenin, which preserves Tcf7 expression and epigenetic stemness, thereby promoting stem-like programs in T cells. Furthermore, in vitro expansion with D-mannose supplementation yields T cell products for adoptive therapy with stemness characteristics, even after extensive long-term expansion, that exhibits enhanced anti-tumor efficacy. These findings reveal cell-intrinsic mannose metabolism as a physiological regulator of CD8+ T cell fate, decoupling proliferation/expansion from differentiation, and underscoring the therapeutic potential of mannose modulation in cancer immunotherapy.

HDAC inhibitor enhances ferroptosis susceptibility of AML cells by stimulating iron metabolism

Acute Myeloid Leukemia (AML) are challenging blood cancers with limited long-term survival rates, necessitating novel therapeutic strategies. This study explored the role of Histone deacetylase (HDAC) inhibitors in enhancing ferroptosis in AML cells by modulating iron metabolism. We demonstrated that HDAC inhibitors (Entinostat and Vorinostat) sensitize AML cells to ferroptosis both in vitro and in vivo. Mechanistically, we show that HDAC inhibitor treatment upregulated the expression of iron metabolism genes that lead to increased labile iron pool. Notably, NCOA4, a ferritin degradation mediator, and HMOX1/2 proteins, involved in heme breakdown, were identified as critical contributors to this process. The functional role of these genes was confirmed through CRISPR-Cas9 mediated knockouts, which significantly rescued cells from HDAC-induced ferroptosis sensitivity. Our results suggest a novel therapeutic approach for AML, where combining HDAC inhibitors with ferroptosis inducers could exploit the disrupted iron metabolism in AML cells. This study highlights the potential of HDAC inhibitors to modulate iron metabolism pathways, offering new insights into the treatment of these malignancies.

Stearoyl-CoA desaturase inhibition is toxic to acute myeloid leukemia displaying high levels of the de novo fatty acid biosynthesis and desaturation

Identification of specific and therapeutically actionable vulnerabilities, ideally present across multiple mutational backgrounds, is needed to improve acute myeloid leukemia (AML) patients' outcomes. We identify stearoyl-CoA desaturase (SCD), the key enzyme in fatty acid (FA) desaturation, as prognostic of patients' outcomes and, using the clinical-grade inhibitor SSI-4, show that SCD inhibition (SCDi) is a therapeutic vulnerability across multiple AML models in vitro and in vivo. Multiomic analysis demonstrates that SCDi causes lipotoxicity, which induces AML cell death via pleiotropic effects. Sensitivity to SCDi correlates with AML dependency on FA desaturation regardless of mutational profile and is modulated by FA biosynthesis activity. Finally, we show that lipotoxicity increases chemotherapy-induced DNA damage and standard chemotherapy further sensitizes AML cells to SCDi. Our work supports developing FA desaturase inhibitors in AML while stressing the importance of identifying predictive biomarkers of response and biologically validated combination therapies to realize their full therapeutic potential.

Mapping Natural Sugars Metabolism in Acute Myeloid Leukaemia Using 2D Nuclear Magnetic Resonance Spectroscopy

Metabolism plays a central role in cancer progression. Rewiring glucose metabolism is essential for fulfilling the high energy and biosynthetic demands as well as for the development of drug resistance. Nevertheless, the role of other diet-abundant natural sugars is not fully understood. In this study, we performed a comprehensive 2D NMR spectroscopy tracer-based assay with a panel of 13C-labelled sugars (glucose, fructose, galactose, mannose and xylose). We assigned over 100 NMR signals from metabolites derived from each sugar and mapped them to metabolic pathways, uncovering two novel findings. First, we demonstrated that mannose has a semi-identical metabolic profile to that of glucose with similar label incorporation patterns. Second, next to the known role of fructose in driving one-carbon metabolism, we explained the equally important contribution of galactose to this pathway. Interestingly, we demonstrated that cells growing with either fructose or galactose became less sensitive to certain one-carbon metabolism inhibitors such as 5-Flurouracil and SHIN1. In summary, this study presents the differential metabolism of natural sugars, demonstrating that mannose has a comparable profile to that of glucose. Conversely, galactose and fructose contribute to a greater extent to one-carbon metabolism, which makes them important modulators for inhibitors targeting this pathway. To our knowledge, this is the first NMR study to comprehensively investigate the metabolism of key natural sugars in AML and cancer.

Manipulating mannose metabolism as a potential anticancer strategy

Cancer cells acquire metabolic advantages over their normal counterparts regarding the use of nutrients for sustained cell proliferation and cell survival in the tumor microenvironment. Notable among the metabolic traits in cancer cells is the Warburg effect, which is a reprogrammed form of glycolysis that favors the rapid generation of ATP from glucose and the production of biological macromolecules by diverting glucose into various metabolic intermediates. Meanwhile, mannose, which is the C-2 epimer of glucose, has the ability to dampen the Warburg effect, resulting in slow-cycling cancer cells that are highly susceptible to chemotherapy. This anticancer effect of mannose appears when its catabolism is compromised in cancer cells. Moreover, de novo synthesis of mannose within cancer cells has also been identified as a potential target for enhancing chemosensitivity through targeting glycosylation pathways. The underlying mechanisms by which alterations in mannose metabolism induce cancer cell vulnerability are just beginning to emerge. This review summarizes the current state of our knowledge of mannose metabolism and provides insights into its manipulation as a potential anticancer strategy.

Ferroptosis in Cancer Therapy: Mechanisms, Small Molecule Inducers, and Novel Approaches

Ferroptosis, a unique form of programmed cell death, is initiated by an excess of iron accumulation and lipid peroxidation-induced damage. There is a growing body of evidence indicating that ferroptosis plays a critical role in the advancement of tumors. The increased metabolic activity and higher iron levels in tumor cells make them particularly vulnerable to ferroptosis. As a result, the targeted induction of ferroptosis is becoming an increasingly promising approach for cancer treatment. This review offers an overview of the regulatory mechanisms of ferroptosis, delves into the mechanism of action of traditional small molecule ferroptosis inducers and their effects on various tumors. In addition, the latest progress in inducing ferroptosis using new means such as proteolysis-targeting chimeras (PROTACs), photodynamic therapy (PDT), sonodynamic therapy (SDT) and nanomaterials is summarized. Finally, this review discusses the challenges and opportunities in the development of ferroptosis-inducing agents, focusing on discovering new targets, improving selectivity, and reducing toxic and side effects.

Genipin inhibits proliferation of gastric cancer cells by inducing ferroptosis: an integrated study of network pharmacology and bioinformatics study

Ferroptosis has been demonstrated to suppress cancer development and is targeted for cancer therapy. Genipin, an iridoid constituent in Gardeniae Fructus, has been reported to exert anti-cancer abilities. However, whether genipin could induce ferroptosis remains unclear. The purpose of this study is to explore the anti-gastric cancer (GC) effects of genipin by inducing ferroptosis and to identify the potential targets. CCK-8 and colony formation assays were performed to evaluate the anti-GC effects of genipin. Flowcytometry and western blot were used to indicate ferroptosis-inducing ability of genipin. The potential targets of genipin were analyzed by network pharmacology, screened using UALCAN and KM-plotter database and evaluated by molecular docking. The results showed that genipin inhibited cell viability and proliferation of GC cells. Genipin treatment decreased levels of GPX4 and SLC7A11, induced accumulation of lipid peroxidation intracellularly and led to ferroptosis in GC cells. Network pharmacology analysis identified that lipid- and ROS-related pathways involved in ferroptosis ranked high among genipin-GC common targets. Data from UALCAN and KM-plotter database demonstrated that expression levels of ferroptosis-related targets, including AURKA, BCAT2, DHODH, and GPI, increased in GC tissues and the higher levels of the above four targets were related to tumor stage, tumor grade, and poor prognosis. Among these four targets, AURKA, BCAT2, and DHODH were confirmed by molecular docking with binding energies less than - 5. Taken together, our study demonstrates that genipin could exert anti-GC ability by inducing ferroptosis and provides evidence for the potential application of genipin in GC treatment.