Oxamate targeting aggressive cancers with special emphasis to brain tumors

Intranuclear TCA and mitochondrial overload: The nascent sprout of tumors metabolism

Abnormal glucose metabolism in tumors is a well-known form of metabolic reprogramming in tumor cells, the most representative of which, the Warburg effect, has been widely studied and discussed since its discovery. However, contradictions in a large number of studies and suboptimal efficacy of drugs targeting glycolysis have prompted us to further deepen our understanding of glucose metabolism in tumors. Here, we review recent studies on mitochondrial overload, nuclear localization of metabolizing enzymes, and intranuclear TCA (nTCA) in the context of the anomalies produced by inhibition of the Warburg effect. We provide plausible explanations for many of the contradictory points in the existing studies, including the causes of the Warburg effect. Furthermore, we provide a detailed prospective discussion of these studies in the context of these new findings, providing new ideas for the use of nTCA and mitochondrial overload in tumor therapy.

Burning lactic acid: a road to revitalizing antitumor immunity

Lactic acid (LA) accumulation in tumor microenvironments (TME) has been implicated in immune suppression and tumor progress. Diverse roles of LA have been elucidated, including microenvironmental pH regulation, signal transduction, post-translational modification, and metabolic remodeling. This review summarizes LA functions within TME, focusing on the effects on tumor cells, immune cells, and stromal cells. Reducing LA levels is a potential strategy to attack cancer, which inevitably affects the physiological functions of normal tissues. Alternatively, transporting LA into the mitochondria as an energy source for immune cells is intriguing. We underscore the significance of LA in both tumor biology and immunology, proposing the burning of LA as a potential therapeutic approach to enhance antitumor immune responses.

Lactate and lactylation in cancer

Accumulated evidence has implicated the diverse and substantial influence of lactate on cellular differentiation and fate regulation in physiological and pathological settings, particularly in intricate conditions such as cancer. Specifically, lactate has been demonstrated to be pivotal in molding the tumor microenvironment (TME) through its effects on different cell populations. Within tumor cells, lactate impacts cell signaling pathways, augments the lactate shuttle process, boosts resistance to oxidative stress, and contributes to lactylation. In various cellular populations, the interplay between lactate and immune cells governs processes such as cell differentiation, immune response, immune surveillance, and treatment effectiveness. Furthermore, communication between lactate and stromal/endothelial cells supports basal membrane (BM) remodeling, epithelial-mesenchymal transitions (EMT), metabolic reprogramming, angiogenesis, and drug resistance. Focusing on lactate production and transport, specifically through lactate dehydrogenase (LDH) and monocarboxylate transporters (MCT), has shown promise in the treatment of cancer. Inhibitors targeting LDH and MCT act as both tumor suppressors and enhancers of immunotherapy, leading to a synergistic therapeutic effect when combined with immunotherapy. The review underscores the importance of lactate in tumor progression and provides valuable perspectives on potential therapeutic approaches that target the vulnerability of lactate metabolism, highlighting the Heel of Achilles for cancer treatment.

Lactylation modification in cardio-cerebral diseases: A state-of-the-art review

Cardio-cerebral diseases (CCDs), encompassing conditions such as coronary heart disease, myocardial infarction, stroke, Alzheimer's disease, et al., represent a significant threat to human health and well-being. These diseases are often characterized by metabolic abnormalities and remodeling in the process of pathology. Glycolysis and hypoxia-induced lactate accumulation play critical roles in cellular energy dynamics and metabolic imbalances in CCDs. Lactylation, a post-translational modification driven by excessive lactate accumulation, occurs in both histone and non-histone proteins. It has been implicated in regulating protein function across various pathological processes in CCDs, including inflammation, angiogenesis, lipid metabolism dysregulation, and fibrosis. Targeting key proteins involved in lactylation, as well as the enzymes regulating this modification, holds promise as a therapeutic strategy to modulate disease progression by addressing these pathological mechanisms. This review provides a holistic picture of the types of lactylation and the associated modifying enzymes, highlights the roles of lactylation in different pathological processes, and synthesizes the latest clinical evidence and preclinical studies in a comprehensive view. We aim to emphasize the potential of lactylation as an innovative therapeutic target for preventing and treating CCD-related conditions.

Progress in Lactate Metabolism and Its Regulation via Small Molecule Drugs

Lactate, once viewed as a byproduct of glycolysis and a metabolic "waste", is now recognized as an energy-providing substrate and a signaling molecule that modulates cellular functions under pathological conditions. The discovery of histone lactylation in 2019 marked a paradigm shift, with subsequent studies revealing that lactate can undergo lactylation with both histone and non-histone proteins, implicating it in the pathogenesis of various diseases, including cancer, liver fibrosis, sepsis, ischemic stroke, and acute kidney injury. Aberrant lactate metabolism is associated with disease onset, and its levels can predict disease outcomes. Targeting lactate production, transport, and lactylation may offer therapeutic potential for multiple diseases, yet a systematic summary of the small molecules modulating lactate and its metabolism in various diseases is lacking. This review outlines the sources and clearance of lactate, as well as its roles in cancer, liver fibrosis, sepsis, ischemic stroke, myocardial infarction, and acute kidney injury, and summarizes the effects of small molecules on lactate regulation. It aims to provide a reference and direction for future research.

Elucidating the causal links between plasma and cerebrospinal fluid metabolites and pituitary tumors: a Mendelian randomization analysis

Background

Pituitary tumors (PTs) are common benign intracranial tumors. Investigating the metabolites in serum and cerebrospinal fluid in PTs is essential to understanding the underlying biological mechanisms and identifying new biomarkers and therapeutic strategies.

Methods

We used the GWAS dataset of PTs from the FinnGen database, a dataset of 486 plasma metabolites from the GWAS catalog database, and a dataset of 338 cerebrospinal fluid (CSF) metabolites from the WADRC and WRAP study collections. An inverse variance weighting (IVW) approach was utilized as the mainly method to investigate causality between metabolites and PTs, supplemented by four complementary methods to strengthen our findings. Additionally, we utilized several sensitivity methods to guarantee the robustness of our findings.

Results

The study identified 17 plasma metabolites and 10 CSF metabolites related to PTs. Among these, 11 metabolites indicated a significant positive causality with PTs, while 16 displayed a remarkable negative causality. Particularly, plasma levels of 3-dehydrocarnitine (OR = 2.73, 95% CI = 1.55-4.83, P = 0.001) and acetylcarnitine (OR = 0.35, 95% CI = 0.19-0.63, P = 0.001) were found to be significant exposure factors for PTs. Multiple sensitivity analyses confirm the robustness of the results. The study found no evidence of a reverse causality between PTs and the plasma levels of 3-dehydrocarnitine and acetylcarnitine.

Conclusions

The present study identified 27 metabolites associated with the incidence of PTs, among which 3-dehydrocarnitine and acetylcarnitine are the most noteworthy.

Inducing disulfidptosis in tumors:potential pathways and significance

Regulated cell death (RCD) is crucial for the elimination of abnormal cells. In recent years, strategies aimed at inducing RCD, particularly apoptosis, have become increasingly important in cancer therapy. However, the ability of tumor cells to evade apoptosis has led to treatment resistance and relapse, prompting extensive research into alternative death processes in cancer cells. A recent study identified a novel form of RCD known as disulfidptosis, which is linked to disulfide stress. Cancer cells import cystine from the extracellular environment via solute carrier family 7 member 11 (SLC7A11) and convert it to cysteine using nicotinamide adenine dinucleotide phosphate (NADPH). When NADPH is deficient or its utilization is impaired, cystine accumulates, leading to the formation of disulfide bonds in the actin cytoskeleton, triggering disulfidptosis. Disulfidptosis reveals a metabolic vulnerability in tumors, offering new insights into cancer therapy strategies. This review provides a detailed overview of the mechanisms underlying disulfidptosis, the current research progress, and limitations. It also highlights innovative strategies for inducing disulfidptosis and explores the potential of combining these approaches with traditional cancer therapies, particularly immunotherapy, to expedite clinical translation.

Lactic acid: The culprit behind the immunosuppressive microenvironment in hepatocellular carcinoma

As a solid tumor with high glycolytic activity, hepatocellular carcinoma (HCC) produces excess lactic acid and increases extracellular acidity, thus forming a unique immunosuppressive microenvironment. L-lactate dehydrogenase (LDH) and monocarboxylate transporters (MCTs) play a very important role in glycolysis. LDH is the key enzyme for lactic acid (LA) production, and MCT is responsible for the cellular import and export of LA. The synergistic effect of the two promotes the formation of an extracellular acidic microenvironment. In the acidic microenvironment of HCC, LA can not only promote the proliferation, survival, transport and angiogenesis of tumor cells but also have a strong impact on immune cells, ultimately leading to an inhibitory immune microenvironment. This article reviews the role of LA in HCC, especially its effect on immune cells, summarizes the progress of LDH and MCT-related drugs, and highlights the potential of immunotherapy targeting lactate combined with HCC.

Emerging roles of the chromatin remodeler MORC2 in cancer metabolism

Cancer is characterized by metabolic reprogramming in cancer cells, which is crucial for tumorigenesis. The highly deregulated chromatin remodeler MORC2 contributes to cell proliferation, invasion, migration, DNA repair, and chemoresistance. MORC2 also plays a key role in metabolic reprogramming, including lipogenesis, glucose, and glutamine metabolism. A recent study showed that MORC2-regulated glucose metabolism affects the expression of E-cadherin, a crucial protein in the epithelial-to-mesenchymal transition. This review discusses recent developments in MORC2 regulated cancer cell metabolism and its role in cancer progression.

Transcriptional regulation and post-translational modifications in the glycolytic pathway for targeted cancer therapy

Cancer cells largely rely on aerobic glycolysis or the Warburg effect to generate essential biomolecules and energy for their rapid growth. The key modulators in glycolysis including glucose transporters and enzymes, e.g. hexokinase 2, enolase 1, pyruvate kinase M2, lactate dehydrogenase A, play indispensable roles in glucose uptake, glucose consumption, ATP generation, lactate production, etc. Transcriptional regulation and post-translational modifications (PTMs) of these critical modulators are important for signal transduction and metabolic reprogramming in the glycolytic pathway, which can provide energy advantages to cancer cell growth. In this review we recapitulate the recent advances in research on glycolytic modulators of cancer cells and analyze the strategies targeting these vital modulators including small-molecule inhibitors and microRNAs (miRNAs) for targeted cancer therapy. We focus on the regulation of the glycolytic pathway at the transcription level (e.g., hypoxia-inducible factor 1, c-MYC, p53, sine oculis homeobox homolog 1, N6-methyladenosine modification) and PTMs (including phosphorylation, methylation, acetylation, ubiquitination, etc.) of the key regulators in these processes. This review will provide a comprehensive understanding of the regulation of the key modulators in the glycolytic pathway and might shed light on the targeted cancer therapy at different molecular levels.

Adiponectin Receptor Agonist AdipoRon Inhibits Proliferation and Drives Glycolytic Dependence in Non-Small-Cell Lung Cancer Cells

Despite the countless therapeutic advances achieved over the years, non-small-cell lung cancer (NSCLC) is the leading cause of cancer-related death worldwide. To this primacy contribute both non-oncogene addicted and advanced NSCLCs, in which conventional therapies are only partially effective. The adiponectin receptor agonist AdipoRon has revealed antiproliferative action in different cancers, including osteosarcoma and pancreatic cancer. Herein, we investigated its potential anticancer role in NSCLC for the first time. We proved that AdipoRon strongly inhibits viability, growth and colony formation in H1299 and A549 NSCLC cells, mainly through a slowdown in cell cycle progression. Along with the biological behaviors, a metabolic switching was observed after AdipoRon administration in NSCLC cells, consisting of higher glucose consumption and lactate accumulation. Remarkably, both 2-Deoxy Glucose and Oxamate glycolytic-interfering agents greatly enhanced AdipoRon's antiproliferative features. As a master regulator of cell metabolism, AMP-activated protein kinase (AMPK) was activated by AdipoRon. Notably, the ablation of AdipoRon-induced AMPK phosphorylation by Compound-C significantly counteracted its effectiveness. However, the engagement of other pathways should be investigated afterwards. With a focus on NSCLC, our findings further support the ability of AdipoRon in acting as an anticancer molecule, driving its endorsement as a future candidate in NSCLC therapy.

Brain Tumor Detection and Categorization with Segmentation of Improved Unsupervised Clustering Approach and Machine Learning Classifier

There is no doubt that brain tumors are one of the leading causes of death in the world. A biopsy is considered the most important procedure in cancer diagnosis, but it comes with drawbacks, including low sensitivity, risks during biopsy treatment, and a lengthy wait for results. Early identification provides patients with a better prognosis and reduces treatment costs. The conventional methods of identifying brain tumors are based on medical professional skills, so there is a possibility of human error. The labor-intensive nature of traditional approaches makes healthcare resources expensive. A variety of imaging methods are available to detect brain tumors, including magnetic resonance imaging (MRI) and computed tomography (CT). Medical imaging research is being advanced by computer-aided diagnostic processes that enable visualization. Using clustering, automatic tumor segmentation leads to accurate tumor detection that reduces risk and helps with effective treatment. This study proposed a better Fuzzy C-Means segmentation algorithm for MRI images. To reduce complexity, the most relevant shape, texture, and color features are selected. The improved Extreme Learning machine classifies the tumors with 98.56% accuracy, 99.14% precision, and 99.25% recall. The proposed classifier consistently demonstrates higher accuracy across all tumor classes compared to existing models. Specifically, the proposed model exhibits accuracy improvements ranging from 1.21% to 6.23% when compared to other models. This consistent enhancement in accuracy emphasizes the robust performance of the proposed classifier, suggesting its potential for more accurate and reliable brain tumor classification. The improved algorithm achieved accuracy, precision, and recall rates of 98.47%, 98.59%, and 98.74% on the Fig share dataset and 99.42%, 99.75%, and 99.28% on the Kaggle dataset, respectively, which surpasses competing algorithms, particularly in detecting glioma grades. The proposed algorithm shows an improvement in accuracy, of approximately 5.39%, in the Fig share dataset and of 6.22% in the Kaggle dataset when compared to existing models. Despite challenges, including artifacts and computational complexity, the study's commitment to refining the technique and addressing limitations positions the improved FCM model as a noteworthy advancement in the realm of precise and efficient brain tumor identification.

Recent progress in metabolic reprogramming in gestational diabetes mellitus: a review

Gestational diabetes mellitus is a prevalent metabolic disease that can impact the normal course of pregnancy and delivery, leading to adverse outcomes for both mother and child. Its pathogenesis is complex and involves various factors, such as insulin resistance and β-cell dysfunction. Metabolic reprogramming, which involves mitochondrial oxidative phosphorylation and glycolysis, is crucial for maintaining human metabolic balance and is involved in the pathogenesis and progression of gestational diabetes mellitus. However, research on the link and metabolic pathways between metabolic reprogramming and gestational diabetes mellitus is limited. Therefore, we reviewed the relationship between metabolic reprogramming and gestational diabetes mellitus to provide new therapeutic strategies for maternal health during pregnancy and reduce the risk of developing gestational diabetes mellitus.

A Review of Advances in Mitochondrial Research in Cancer

BACKGROUND

Abnormalities in mitochondrial structure or function are closely related to the development of malignant tumors. Mitochondrial metabolic reprogramming provides precursor substances and energy for the vital activities of tumor cells, so that cancer cells can rapidly adapt to the unfavorable environment of hypoxia and nutrient deficiency. Mitochondria can enable tumor cells to gain the ability to proliferate, escape immune responses, and develop drug resistance by altering constitutive junctions, oxidative phosphorylation, oxidative stress, and mitochondrial subcellular relocalization. This greatly reduces the rate of effective clinical control of tumors.

PURPOSE

Explore the major role of mitochondria in cancer, as well as targeted mitochondrial therapies and mitochondria-associated markers.

CONCLUSIONS

This review provides a comprehensive analysis of the various aspects of mitochondrial aberrations and addresses drugs that target mitochondrial therapy, providing a basis for clinical mitochondria-targeted anti-tumor therapy.

Metabolic reprogramming in nasopharyngeal carcinoma: Mechanisms and therapeutic opportunities

The high prevalence of metabolic reprogramming in nasopharyngeal carcinoma (NPC) offers an abundance of potential therapeutic targets. This review delves into the distinct mechanisms underlying metabolic reprogramming in NPC, including enhanced glycolysis, nucleotide synthesis, and lipid metabolism. All of these changes are modulated by Epstein-Barr virus (EBV) infection, hypoxia, and tumor microenvironment. We highlight the role of metabolic reprogramming in the development of NPC resistance to standard therapies, which represents a challenging barrier in treating this malignancy. Furthermore, we dissect the state of the art in therapeutic strategies that target these metabolic changes, evaluating the successes and failures of clinical trials and the strategies to tackle resistance mechanisms. By providing a comprehensive overview of the current knowledge and future directions in this field, this review sets the stage for new therapeutic avenues in NPC.

Oxamate enhances the efficacy of CAR-T therapy against glioblastoma via suppressing ectonucleotidases and CCR8 lactylation

BACKGROUND

Chimeric antigen receptor (CAR)-T immunotherapy fails to treat solid tumors due in part to immunosuppressive microenvironment. Excess lactate produced by tumor glycolysis increases CAR-T immunosuppression. The mechanism of lactate inducing the formation of immunosuppressive microenvironment remains to be further explored.

METHODS

Immunocyte subpopulations and molecular characteristics were analyzed in the orthotopic xenografts of nude mice using flow cytometry assay and immunohistochemical staining after oxamate, a lactate dehydrogenase A (LDHA) inhibitor, and control T or CAR-T cells injection alone or in combination. RT-qPCR, western blot, flow cytometry, immunofluorescence, luciferase reporter assay, chromatin immunoprecipitation and ELISA were performed to measure the effect of lactate on the regulation of CD39, CD73 and CCR8 in cultured glioma stem cells, CD4 + T cells or macrophages.

RESULTS

Oxamate promoted immune activation of tumor-infiltrating CAR-T cells through altering the phenotypes of immune molecules and increasing regulatory T (Treg) cells infiltration in a glioblastoma mouse model. Lactate accumulation within cells upregulated CD39, CD73 and CCR8 expressions in both lactate-treated cells and glioma stem cells-co-cultured CD4 + T cells and macrophages, and intracellular lactate directly elevated the activities of these gene promotors through histone H3K18 lactylation.

CONCLUSIONS

Utilizing lactate generation inhibitor not only reprogramed glucose metabolism of cancer stem cells, but also alleviated immunosuppression of tumor microenvironment and reduced tumor-infiltrating CAR-Treg cells, which may be a potential strategy to enhance CAR-T function in glioblastoma therapy.

Surviving the hunger games: Metabolic reprogramming in medulloblastoma

Medulloblastoma is a highly malignant pediatric brain tumor characterized by its aggressive nature and limited treatment options. Metabolic changes have recently emerged as key factors in the development, progression, and response to therapy in various types of cancer. Cancer cells exhibit remarkable adaptability by modulating glucose, lipids, amino acids, and nucleotide metabolism to survive in nutrient- and oxygen-deprived environments. Although medulloblastoma has been extensively studied from a genomic perspective, leading to the identification of four subgroups and their respective subcategories, the investigation of its metabolic phenotype has remained relatively understudied. This review focus on the available literature, aiming to summarize the current knowledge about the main metabolic pathways that are deregulated in medulloblastoma tumors, while emphasizing the controversial aspects and the progress that is yet to be made. Furthermore, we underscored the insights gained so far regarding the impact of metabolism on the development of drug resistance in medulloblastoma and the therapeutic strategies employed to target specific metabolic pathways.

Lactate metabolic pathway regulates tumor cell metastasis and its use as a new therapeutic target

Abnormal energy metabolism is one of the ten hallmarks of tumors, and tumor cell metabolism provides energy and a suitable microenvironment for tumorigenesis and metastasis. Tumor cells can consume large amounts of glucose and produce large amounts of lactate through glycolysis even in the presence of oxygen, a process called aerobic glycolysis, also known as the Warburg effect. Lactate is the end product of the aerobic glycolysis. Lactate dehydrogenase A (LDHA), which is highly expressed in cancer cells, promotes lactate production and transports lactate to the tumor microenvironment and is taken up by surrounding stromal cells under the action of monocarboxylate transporter 1/4 (MCT1/4), which in turn influences the immune response and enhances the invasion and metastasis of cancer cells. Therapeutic strategies targeting lactate metabolism have been intensively investigated, focusing on its metastasis-promoting properties and various target inhibitors; AZD3965, an MCT1 inhibitor, has entered phase I clinical trials, and the LDHA inhibitor N-hydroxyindole (NHI) has shown cancer therapeutic activity in pre-clinical studies. Interventions targeting lactate metabolism are emerging as a promising option for cancer therapy, with chemotherapy or radiotherapy combined with lactate-metabolism-targeted drugs adding to the effectiveness of cancer treatment. Based on current research, this article outlines the role of lactate metabolism in tumor metastasis and the potential value of inhibitors targeting lactate metabolism in cancer therapy.

Staphylococcus epidermidis biofilms undergo metabolic and matrix remodeling under nitrosative stress

Staphylococcus epidermidis is a commensal skin bacterium that forms host- and antibiotic-resistant biofilms that are a major cause of implant-associated infections. Most research has focused on studying the responses to host-imposed stresses on planktonic bacteria. In this work, we addressed the open question of how S. epidermidis thrives on toxic concentrations of nitric oxide (NO) produced by host innate immune cells during biofilm assembly. We analyzed alterations of gene expression, metabolism, and matrix structure of biofilms of two clinical isolates of S. epidermidis, namely, 1457 and RP62A, formed under NO stress conditions. In both strains, NO lowers the amount of biofilm mass and causes increased production of lactate and decreased acetate excretion from biofilm glucose metabolism. Transcriptional analysis revealed that NO induces icaA, which is directly involved in polysaccharide intercellular adhesion (PIA) production, and genes encoding proteins of the amino sugar pathway (glmM and glmU) that link glycolysis to PIA synthesis. However, the strains seem to have distinct regulatory mechanisms to boost lactate production, as NO causes a substantial upregulation of ldh gene in strain RP62A but not in strain 1457. The analysis of the matrix components of the staphylococcal biofilms, assessed by confocal laser scanning microscopy (CLSM), showed that NO stimulates PIA and protein production and interferes with biofilm structure in a strain-dependent manner, but independently of the Ldh level. Thus, NO resistance is attained by remodeling the staphylococcal matrix architecture and adaptation of main metabolic processes, likely providing in vivo fitness of S. epidermidis biofilms contacting NO-proficient macrophages.

A triple-drug combination induces apoptosis in cervical cancer-derived cell lines

Introduction

Cervical cancer is a worldwide health problem due to the number of deaths caused by this neoplasm. In particular, in 2020, 30,000 deaths of this type of tumor were reported in Latin America. Treatments used to manage patients diagnosed in the early stages have excellent results as measured by different clinical outcomes. Existing first-line treatments are not enough to avoid cancer recurrence, progression, or metastasis in locally advanced and advanced stages. Therefore, there is a need to continue with the proposal of new therapies. Drug repositioning is a strategy to explore known medicines as treatments for other diseases. In this scenario, drugs used in other pathologies that have antitumor activity, such as metformin and sodium oxamate, are analyzed.

Methods

In this research, we combined the drugs metformin and sodium oxamate with doxorubicin (named triple therapy or TT) based on their mechanism of action and previous investigation of our group against three CC cell lines.

Results

Through flow cytometry, Western blot, and protein microarray experiments, we found TT-induced apoptosis on HeLa, CaSki, and SiHa through the caspase 3 intrinsic pathway, including the critical proapoptotic proteins BAD, BAX, cytochrome-C, and p21. In addition, mTOR and S6K phosphorylated proteins were inhibited in the three cell lines. Also, we show an anti-migratory activity of the TT, suggesting other targets of the drug combination in the late CC stages.

Discussion

These results, together with our former studies, conclude that TT inhibits the mTOR pathway leading to cell death by apoptosis. Our work provides new evidence of TT against cervical cancer as a promising antineoplastic therapy.

The Oligostilbene Gnetin H Is a Novel Glycolysis Inhibitor That Regulates Thioredoxin Interacting Protein Expression and Synergizes with OXPHOS Inhibitor in Cancer Cells

Since aerobic glycolysis was first observed in tumors almost a century ago by Otto Warburg, the field of cancer cell metabolism has sparked the interest of scientists around the world as it might offer new avenues of treatment for malignant cells. Our current study claims the discovery of gnetin H (GH) as a novel glycolysis inhibitor that can decrease metabolic activity and lactic acid synthesis and displays a strong cytostatic effect in melanoma and glioblastoma cells. Compared to most of the other glycolysis inhibitors used in combination with the complex-1 mitochondrial inhibitor phenformin (Phen), GH more potently inhibited cell growth. RNA-Seq with the T98G glioblastoma cell line treated with GH showed more than an 80-fold reduction in thioredoxin interacting protein (TXNIP) expression, indicating that GH has a direct effect on regulating a key gene involved in the homeostasis of cellular glucose. GH in combination with phenformin also substantially enhances the levels of p-AMPK, a marker of metabolic catastrophe. These findings suggest that the concurrent use of the glycolytic inhibitor GH with a complex-1 mitochondrial inhibitor could be used as a powerful tool for inducing metabolic catastrophe in cancer cells and reducing their growth.

Anti-GD2 immunoliposomes loaded with oxamate for neuroblastoma

Oncometabolism can be targeted for the development of less myelotoxic oncotherapeutics. Lactate dehydrogenase A (LDHA) is central to the Warburg effect, a potential oncometabolic shift in neuroblastoma (NBL). Advanced surgical, cytotoxic and cell-differentiating therapies improved survival of children with NBL. Anti-GD2 monoclonal antibodies (mAb) effectively targeting NBL are also incorporated into complex therapies. However, poor clinical outcomes of high-risk NBL require improvements. Here, we verified the pre-reported prognostic value of LDHA expression in NBL using the R2 onco-genomics platform. Kaplan-Meier curves re-demonstrated that higher tumor LDHA expression correlates with worse survival. Multivariate statistics confirmed LDHA is independent from age, stage, and MYCN amplification. In conclusion, a molecular construct is proposed with anti-GD2 mAbs utilized for the targeted delivery of liposomes containing an LDHA inhibitor, Oxamate. Development and preclinical testing of this immunoliposome may validate targeted inhibition of the Warburg effect for NBL. IMPACT: Development of therapeutics against oncometabolism. Targeted specified drug-delivery with mAb. Sparing normal tissues from profound LDHA inhibition. Immunoliposome loaded with an anti-metabolite. If preclinically successful, has translational potential.

Modulating Glycolysis to Improve Cancer Therapy

Cancer cells undergo metabolic reprogramming and switch to a 'glycolysis-dominant' metabolic profile to promote their survival and meet their requirements for energy and macromolecules. This phenomenon, also known as the 'Warburg effect,' provides a survival advantage to the cancer cells and make the tumor environment more pro-cancerous. Additionally, the increased glycolytic dependence also promotes chemo/radio resistance. A similar switch to a glycolytic metabolic profile is also shown by the immune cells in the tumor microenvironment, inducing a competition between the cancer cells and the tumor-infiltrating cells over nutrients. Several recent studies have shown that targeting the enhanced glycolysis in cancer cells is a promising strategy to make them more susceptible to treatment with other conventional treatment modalities, including chemotherapy, radiotherapy, hormonal therapy, immunotherapy, and photodynamic therapy. Although several targeting strategies have been developed and several of them are in different stages of pre-clinical and clinical evaluation, there is still a lack of effective strategies to specifically target cancer cell glycolysis to improve treatment efficacy. Herein, we have reviewed our current understanding of the role of metabolic reprogramming in cancer cells and how targeting this phenomenon could be a potential strategy to improve the efficacy of conventional cancer therapy.

Siah2 inhibitor and the metabolic antagonist Oxamate retard colon cancer progression and downregulate PD1 expression

BACKGROUND

Solid tumors such as colon cancer are characterized by rapid and sustained cell proliferation, which ultimately results in hypoxia, induction of hypoxia-inducible factor-1α (HIF-1α), and activation of glycolysis to promote tumor survival and immune evasion. We hypothesized that a combinatorial approach of menadione (MEN) as an indirect HIF-1α inhibitor and sodium oxamate (OX) as a glycolysis inhibitor may be a promising treatment strategy for colon cancer.

OBJECTIVES

We investigated the potential efficacy of this combination for promoting an antitumor immune response and suppressing tumor growth in a rat model of colon cancer.

METHODS

Colon cancer was induced by once-weekly subcutaneous injection of 20 mg/kg dimethylhydrazine (DMH) for 16 weeks. Control rats received the vehicle and then no further treatment (negative control) or MEN plus OX for 4 weeks (drug control). Dimethylhydrazine-treated rats were then randomly allocated to four groups: DMH alone group and other groups treated with MEN, OX, and a combination of (MEN and OX) for 4 weeks. Serum samples were assayed for the tumor marker carbohydrate antigen (CA19.9), while expression levels of HIF-1α, caspase-3, PHD3, LDH, and PD1 were evaluated in colon tissue samples by immunoassay and qRT-PCR. Additionally, Ki-67 and Siah2 expression levels were examined by immunohistochemistry.

RESULTS

The combination of MEN plus OX demonstrated a greater inhibitory effect on the expression levels of HIF-1α, Siah2, LDH, Ki-67, and PD1, and greater enhancement of caspase-3 and PHD3 expression in colon cancer tissues than either drug alone.

CONCLUSION

Simultaneous targeting of hypoxia and glycolysis pathways by a combination of MEN and OX could be a promising therapy for inhibiting colon cancer cell growth and promoting antitumor immunity [1].

Tadalafil increases the antitumor activity of 5-FU through inhibiting PRMT5-mediated glycolysis and cell proliferation in colorectal cancer

BACKGROUND

Protein arginine methyltransferase 5 (PRMT5) is upregulated in multiple tumors and plays a pivotal role in cancer cell proliferation. However, the role of PRMT5 in colorectal cancer remains poorly understood.

METHODS

We detected the expression level of PRMT5 and glycolytic enzymes using online databases and colorectal cancer cell lines by immunohistochemical staining, quantitative real-time polymerase chain reaction (qRT-PCR), and western blotting. And MTT and colony formation assays were conducted to investigate cell proliferation. Then, we evaluated ECAR and OCR levels using a biological energy analyzer to investigate the energy status of colorectal cancer, and the transcriptional regulation was detected by dual luciferase reporter assay and ChIP assay. Finally, the efficacy of combined treatment of tadalafil and 5-FU was verified.

RESULTS

PRMT5 was highly expressed in colorectal cancer tissues compared with their normal counterparts and correlated with poor prognosis in CRC patients. Then, we demonstrated that PRMT5 knockdown or loss of function attenuated the viability of CRC cells, while overexpression of PRMT5 promoted cell proliferation. Mechanistically, PRMT5 enhanced glycolysis through transcriptionally activating LDHA expression. In addition, the PRMT5 inhibitor, tadalafil, rendered CRC cells sensitive to antitumor agent 5-FU in vitro and in vivo.

CONCLUSIONS

Our data indicates that PRMT5 promoted colorectal cancer proliferation partially through activating glycolysis and may be a potential target for colorectal cancer therapy.

Targeting Glucose Metabolism Enzymes in Cancer Treatment: Current and Emerging Strategies

Simple Summary

Reprogramming of glucose metabolism is a hallmark of cancer and can be targeted by therapeutic agents. Some metabolism regulators, such as ivosidenib and enasidenib, have been approved for cancer treatment. Currently, more advanced and effective glucose metabolism enzyme-targeted anticancer drugs have been developed. Furthermore, some natural products have shown efficacy in killing tumor cells by regulating glucose metabolism, offering novel therapeutic opportunities in cancer. However, most of them have failed to be translated into clinical applications due to low selectivity, high toxicity, and side effects. Recent studies suggest that combining glucose metabolism modulators with chemotherapeutic drugs, immunotherapeutic drugs, and other conventional anticancer drugs may be a future direction for cancer treatment.

Abstract

Reprogramming of glucose metabolism provides sufficient energy and raw materials for the proliferation, metastasis, and immune escape of cancer cells, which is enabled by glucose metabolism-related enzymes that are abundantly expressed in a broad range of cancers. Therefore, targeting glucose metabolism enzymes has emerged as a promising strategy for anticancer drug development. Although several glucose metabolism modulators have been approved for cancer treatment in recent years, some limitations exist, such as a short half-life, poor solubility, and numerous adverse effects. With the rapid development of medicinal chemicals, more advanced and effective glucose metabolism enzyme-targeted anticancer drugs have been developed. Additionally, several studies have found that some natural products can suppress cancer progression by regulating glucose metabolism enzymes. In this review, we summarize the mechanisms underlying the reprogramming of glucose metabolism and present enzymes that could serve as therapeutic targets. In addition, we systematically review the existing drugs targeting glucose metabolism enzymes, including small-molecule modulators and natural products. Finally, the opportunities and challenges for glucose metabolism enzyme-targeted anticancer drugs are also discussed. In conclusion, combining glucose metabolism modulators with conventional anticancer drugs may be a promising cancer treatment strategy.

Revealing the crosstalk between nasopharyngeal carcinoma and immune cells in the tumor microenvironment

Nasopharyngeal carcinoma (NPC) arises from the epithelial cells located in the nasopharynx and has a distinct geographic distribution. Chronic Epstein-Barr virus (EBV) infection, as its most common causative agents, can be detected in 100% of NPC types. In-depth studies of the cellular and molecular events leading to immunosuppression in NPC have revealed new therapeutic targets and diverse combinations that promise to benefit patients with highly refractory, advanced and metastatic NPC. This paper reviews the mechanisms by which NPC cells to circumvent immune surveillance and approaches being attempted to restore immunity. We integrate existing insights into anti-NPC immunity and molecular signaling pathways as well as targeting therapies in anticipation of broader applicability and effectiveness in advanced metastatic NPC.

Transcriptional, chromatin, and metabolic landscapes of LDHA inhibitor-resistant pancreatic ductal adenocarcinoma

Metabolic reprogramming, due in part to the overexpression of metabolic enzymes, is a key hallmark of cancer cells. Lactate dehydrogenase (LDHA), a metabolic enzyme that catalyzes the interconversion of lactate and pyruvate, is overexpressed in a wide variety of cancer types, including pancreatic ductal adenocarcinoma (PDAC). Furthermore, the genetic or pharmacological inhibition of LDHA suppresses cancer growth, demonstrating a cancer-promoting role for this enzyme. Therefore, several pharmacological LDHA inhibitors are being developed and tested as potential anti-cancer therapeutic agents. Because cancer cells are known to rapidly adapt and become resistant to anti-cancer therapies, in this study, we modeled the adaptation of cancer cells to LDHA inhibition. Using PDAC as a model system, we studied the molecular aspects of cells resistant to the competitive LDHA inhibitor sodium oxamate. We performed unbiased RNA-sequencing (RNA-seq), assay for transposase-accessible chromatin with sequencing (ATAC-seq), and metabolomics analyses of parental and oxamate-resistant PDAC cells treated with and without oxamate to identify the transcriptional, chromatin, and metabolic landscapes of these cells. We found that oxamate-resistant PDAC cells were significantly different from parental cells at the levels of mRNA expression, chromatin accessibility, and metabolites. Additionally, an integrative analysis combining the RNA-seq and ATAC-seq datasets identified a subset of differentially expressed mRNAs that directly correlated with changes in chromatin accessibility. Finally, functional analysis of differentially expressed metabolic genes in parental and oxamate-resistant PDAC cells treated with and without oxamate, together with an integrative analysis of RNA-seq and metabolomics data, revealed changes in metabolic enzymes that might explain the changes in metabolite levels observed in these cells. Collectively, these studies identify the transcriptional, chromatin, and metabolic landscapes of LDHA inhibitor resistance in PDAC cells. Future functional studies related to these changes remain necessary to reveal the direct roles played by these changes in the development of LDHA inhibitor resistance and uncover approaches for more effective use of LDHA inhibitors in cancer therapy.