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Cancer cells reprogram their metabolism to promote growth and proliferation. The genetic evidence pointing to the importance of the amino acid serine in tumorigenesis is striking. The gene encoding the enzyme 3-phosphoglycerate dehydrogenase (PHGDH), which catalyzes the first committed step of serine biosynthesis, is overexpressed in tumors and cancer cell lines via focal amplification and nuclear factor erythroid-2-related factor 2 (NRF2)-mediated up-regulation. PHGDH-overexpressing cells are exquisitely sensitive to genetic ablation of the pathway. Here, we report the discovery of a selective small molecule inhibitor of PHGDH, CBR-5884, identified by screening a library of 800,000 drug-like compounds. CBR-5884 inhibited de novo serine synthesis in cancer cells and was selectively toxic to cancer cell lines with high serine biosynthetic activity. Biochemical characterization of the inhibitor revealed that it was a noncompetitive inhibitor that showed a time-dependent onset of inhibition and disrupted the oligomerization state of PHGDH. The identification of a small molecule inhibitor of PHGDH not only enables thorough preclinical evaluation of PHGDH as a target in cancers, but also provides a tool with which to study serine metabolism. [ABSTRACT FROM AUTHOR]

Summary The mammalian target of rapamycin complex 1 (mTORC1) regulates activation of immune cells and cellular energy metabolism. Although glycolysis has been linked to immune functions, the mechanisms by which glycolysis regulates NLRP3 inflammasome activation remain unclear. Here, we demonstrate that mTORC1-induced glycolysis provides an essential mechanism for NLRP3 inflammasome activation. Moreover, we demonstrate that hexokinase 1 (HK1)-dependent glycolysis, under the regulation of mTORC1, represents a critical metabolic pathway for NLRP3 inflammasome activation. Downregulation of glycolysis by inhibition of Raptor/mTORC1 or HK1 suppressed both pro-IL-1β maturation and caspase-1 activation in macrophages in response to LPS and ATP. These results suggest that upregulation of HK1-dependent glycolysis by mTORC1 regulates NLRP3 inflammasome activation. [ABSTRACT FROM AUTHOR]

Ferroptosis is a pervasive non-apoptotic form of cell death highly relevant in various degenerative diseases and malignancies. The hallmark of ferroptosis is uncontrolled and overwhelming peroxidation of polyunsaturated fatty acids contained in membrane phospholipids, which eventually leads to rupture of the plasma membrane. Ferroptosis is unique in that it is essentially a spontaneous, uncatalyzed chemical process based on perturbed iron and redox homeostasis contributing to the cell death process, but that it is nonetheless modulated by many metabolic nodes that impinge on the cells' susceptibility to ferroptosis. Among the various nodes affecting ferroptosis sensitivity, several have emerged as promising candidates for pharmacological intervention, rendering ferroptosis-related proteins attractive targets for the treatment of numerous currently incurable diseases. Herein, the current members of a Germany-wide research consortium focusing on ferroptosis research, as well as key external experts in ferroptosis who have made seminal contributions to this rapidly growing and exciting field of research, have gathered to provide a comprehensive, state-of-the-art review on ferroptosis. Specific topics include: basic mechanisms, in vivo relevance, specialized methodologies, chemical and pharmacological tools, and the potential contribution of ferroptosis to disease etiopathology and progression. We hope that this article will not only provide established scientists and newcomers to the field with an overview of the multiple facets of ferroptosis, but also encourage additional efforts to characterize further molecular pathways modulating ferroptosis, with the ultimate goal to develop novel pharmacotherapies to tackle the various diseases associated with - or caused by - ferroptosis., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: SJD is a co-founder of Prothegen, Inc. and holds patents related to ferroptosis. XJ is an inventor on patents related to autophagy and cell death and holds equity of and consults for Exarta Therapeutics and Lime Therapeutics. JAO is a member of the scientific advisory board for Vicinitas Therapeutics and has patent applications related to ferroptosis. TP reports grants from Dracen Pharmaceuticals, Kymera Therapeutics, Bristol-Myers Squibb, Agios Pharmaceuticals, personal fees from Vividion Therapeutics, Tohoku University, and personal fees from Faeth Therapeutics outside the submitted work; in addition, TP has a patent for US-20210361603-A1 pending and a patent for US-20210085763-A1 pending. BRS is an inventor on patents and patent applications involving ferroptosis, holds equity in and serves as a consultant to Exarta Therapeutics, and ProJenX Inc, holds equity in Sonata Therapeutics, and serves as a consultant to Weatherwax Biotechnologies Corporation and Akin Gump Strauss Hauer & Feld LLP. TVB holds patents related to ferroptosis inhibitors. CWil is a consultant for Odyssey Therapeutics and Orphagen Pharmaceuticals. YZ is a consultant for Keen Therapeutics. BP and MC hold patents for some of the compounds described herein, and is co-founder and shareholder of ROSCUE Therapeutics., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

The nonphysiological nutrient levels found in traditional culture media have been shown to affect numerous aspects of cancer cell physiology, including how cells respond to certain therapeutic agents. Here, we comprehensively evaluated how physiological nutrient levels affect therapeutic response by performing drug screening in human plasma-like medium. We observed dramatic nutrient-dependent changes in sensitivity to a variety of FDA-approved and clinically trialed compounds, including rigosertib, an experimental cancer therapeutic that recently failed in phase III clinical trials. Mechanistically, we found that the ability of rigosertib to destabilize microtubules is strongly inhibited by the purine metabolism end product uric acid, which is uniquely abundant in humans relative to traditional in vitro and in vivo cancer models. These results demonstrate the broad and dramatic effects nutrient levels can have on drug response and how incorporation of human-specific physiological nutrient medium might help identify compounds whose efficacy could be influenced in humans.

The analysis of metabolic perturbation in biological samples is crucial to understand mechanisms of metabolic diseases. Here, we describe a protocol for quantitative stable isotope-labeled metabolite tracing of cysteine metabolism in cultured cells. This protocol relies on an extraction protocol to derivatize free thiols to prevent oxidation. In addition, the quantitative tracing of serine into multiple pathways, including the glutathione synthesis pathway, allows for the interrogation of cysteine and glutathione synthesis. This protocol provides a flexible framework that can be adapted to interrogate many metabolites and pathways of interest., (© 2023. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Cells are subjected to oxidative stress during the initiation and progression of tumors, and this imposes selective pressure for cancer cells to adapt mechanisms to tolerate these conditions. Here, we examined the dependency of cancer cells on glutathione (GSH), the most abundant cellular antioxidant. While cancer cell lines displayed a broad range of sensitivities to inhibition of GSH synthesis, the majority were resistant to GSH depletion. To identify cellular pathways required for this resistance, we carried out genetic and pharmacologic screens. Both approaches revealed that inhibition of deubiquitinating enzymes (DUBs) sensitizes cancer cells to GSH depletion. Inhibition of GSH synthesis, in combination with DUB inhibition, led to an accumulation of polyubiquitinated proteins, induction of proteotoxic stress, and cell death. These results indicate that depletion of GSH renders cancer cells dependent on DUB activity to maintain protein homeostasis and cell viability and reveal a potentially exploitable vulnerability for cancer therapy., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Metabolic dysregulation is an appreciated hallmark of cancer and a target for therapeutic intervention. Cellular metabolism involves a series of oxidation/reduction (redox) reactions that yield the energy and biomass required for tumor growth. Cells require diverse molecular species with constituent sulfur atoms to facilitate these processes. For humans, this sulfur is derived from the dietary consumption of the proteinogenic amino acids cysteine and methionine, as only lower organisms (e.g., bacteria, fungi, and plants) can synthesize them de novo. In addition to providing the sulfur required to sustain redox chemistry, the metabolism of these sulfur-containing amino acids yield intermediate metabolites that constitute the cellular antioxidant system, mediate inter- and intracellular signaling, and facilitate the epigenetic regulation of gene expression, all of which contribute to tumorigenesis., (© 2019 Elsevier Inc. All rights reserved.)

Pancreatic ductal adenocarcinoma (PDA) is arguably the most lethal malignancy in the United States. Despite the identification of many molecular alterations in PDA, this information has not translated into effective therapeutic strategies to date. A recent report in Cancer Cell (Fernandez-Zapico et al, Cancer Cell 2005, 7:39-49) reveals an unexpected role for the hematopoietic-specific RhoGEF VAV1 in pancreatic tumorigenesis, where ectopic expression of VAV1 as a result of promoter demethylation was identified in the majority of established cell lines and PDA tissue samples. Importantly, VAV1 expression was functionally required for optimal proliferation, transformation and survival of pancreatic cancer cell lines. This study provides the first evidence of VAV1 promoter demethylation as an event in cancer progression, suggesting that aberrant signaling pathways driven by VAV1 are potential therapeutic targets in PDA.