Simultaneous targeting of glycolysis and oxidative phosphorylation as a therapeutic strategy to treat diffuse large B-cell lymphoma

Transcriptional activation of SIRT5 by FOXA1 reprograms glycolysis to facilitate the malignant progression of diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) is the most common diagnosed subtype of lymphoma with high invasiveness and heterogeneity. Glycolysis is involved in regulating DLBCL progression. We aimed to explore the role of forkhead box protein A1 (FOXA1) in DLBCL and the mechanisms related to sirtuine5 (SIRT5) and glycolysis. FOXA1 expression in DLBCL cells was analyzed. Then, the proliferation and apoptosis of DLBCL cells were detected using Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EDU) staining and flow cytometry analysis following FOXA1 or SIRT5 knockdown. The glycolysis was assessed by measuring extracellular acidification rate (ECAR), glucose consumption and lactate secretion. Immunoblotting was employed to examine the expression of apoptosis- and glycolysis-related proteins. Additionally, luciferase reporter assay and chromatin immunoprecipitation (ChIP) assay were conducted to test the combination of FOXA1 to SIRT5 promotor region. Subsequently, SIRT5 expression was upregulated to conduct rescue assays. Finally, the effects of FOXA1 downregulation on the growth and glycolysis in OCI-ly7 tumor-bearing mice were examined. As a result, FOXA1 was upregulated in DLBCL cells and FOXA1 or SIRT5 knockdown inhibited the proliferation, accelerated the apoptosis and suppressed glycolysis reprograming in DLBCL cells. Importantly, FOXA1 could transcriptionally activate SIRT5 expression in DLBCL cells. Besides, SIRT5 overexpression counteracted the effects of FOXA1 deficiency on the proliferation, apoptosis and glycolysis reprogramming in DLBCL cells. Furthermore, FOXA1 knockdown inhibited the tumor growth, suppressed the glycolysis reprogramming and downregulated SIRT5 expression in vivo. In summary, FOXA1 could transcriptionally activate SIRT5 to reprogram glycolysis, thereby facilitating the malignant progression of DLBCL.

Metabolic regulation of the immune system in health and diseases: mechanisms and interventions

Metabolism, including glycolysis, oxidative phosphorylation, fatty acid oxidation, and other metabolic pathways, impacts the phenotypes and functions of immune cells. The metabolic regulation of the immune system is important in the pathogenesis and progression of numerous diseases, such as cancers, autoimmune diseases and metabolic diseases. The concept of immunometabolism was introduced over a decade ago to elucidate the intricate interplay between metabolism and immunity. The definition of immunometabolism has expanded from chronic low-grade inflammation in metabolic diseases to metabolic reprogramming of immune cells in various diseases. With immunometabolism being proposed and developed, the metabolic regulation of the immune system can be gradually summarized and becomes more and more clearer. In the context of many diseases including cancer, autoimmune diseases, metabolic diseases, and many other disease, metabolic reprogramming occurs in immune cells inducing proinflammatory or anti-inflammatory effects. The phenotypic and functional changes of immune cells caused by metabolic regulation further affect and development of diseases. Based on experimental results, targeting cellular metabolism of immune cells becomes a promising therapy. In this review, we focus on immune cells to introduce their metabolic pathways and metabolic reprogramming, and summarize how these metabolic pathways affect immune effects in the context of diseases. We thoroughly explore targets and treatments based on immunometabolism in existing studies. The challenges of translating experimental results into clinical applications in the field of immunometabolism are also summarized. We believe that a better understanding of immune regulation in health and diseases will improve the management of most diseases.

Metabolomics for hematologic malignancies: Advances and perspective

With the use of advanced technology, metabolomics allows for a thorough examination of metabolites and other small molecules found in biological specimens, blood, and tissues. In recent years, metabolomics has been recognized that is closely related to the development of malignancies in the hematological system. Alterations in metabolomic pathways and networks are important in the pathogenesis of hematologic malignancies and can also provide a theoretical basis for early diagnosis, efficacy evaluation, accurate staging, and individualized targeted therapy. In this review, we summarize the progress of metabolomics, including glucose metabolism, amino acid metabolism, and lipid metabolism in lymphoma, myeloma, and leukemia through specific mechanisms and pathways. The research of metabolomics gives a new insight and provides therapeutic targets for the treatment of patients with hematologic malignancies.

Mitochondrial reprogramming by activating OXPHOS via glutamine metabolism in African American patients with bladder cancer

Bladder cancer (BLCA) mortality is higher in African American (AA) patients compared with European American (EA) patients, but the molecular mechanism underlying race-specific differences are unknown. To address this gap, we conducted comprehensive RNA-Seq, proteomics, and metabolomics analysis of BLCA tumors from AA and EA. Our findings reveal a distinct metabolic phenotype in AA BLCA characterized by elevated mitochondrial oxidative phosphorylation (OXPHOS), particularly through the activation of complex I. The results provide insight into the complex I activation-driven higher OXPHOS activity resulting in glutamine-mediated metabolic rewiring and increased disease progression, which was also confirmed by [U]13C-glutamine tracing. Mechanistic studies further demonstrate that knockdown of NDUFB8, one of the components of complex I in AA BLCA cells, resulted in reduced basal respiration, ATP production, GLS1 expression, and proliferation. Moreover, preclinical studies demonstrate the therapeutic potential of targeting complex I, as evidenced by decreased tumor growth in NDUFB8-depleted AA BLCA tumors. Additionally, genetic and pharmacological inhibition of GLS1 attenuated mitochondrial respiration rates and tumor growth potential in AA BLCA. Taken together, these findings provide insight into BLCA disparity for targeting GLS1-Complex I for future therapy.

Discovery of PRMT3 Degrader for the Treatment of Acute Leukemia

Protein arginine methyltransferase 3 (PRMT3) plays an important role in gene regulation and a variety of cellular functions, thus, being a long sought-after therapeutic target for human cancers. Although a few PRMT3 inhibitors are developed to prevent the catalytic activity of PRMT3, there is little success in removing the cellular levels of PRMT3-deposited ω-NG,NG-asymmetric dimethylarginine (ADMA) with small molecules. Moreover, the non-enzymatic functions of PRMT3 remain required to be clarified. Here, the development of a first-in-class MDM2-based PRMT3-targeted Proteolysis Targeting Chimeras (PROTACs) 11 that selectively reduced both PRMT3 protein and ADMA is reported. Importantly, 11 inhibited acute leukemia cell growth and is more effective than PRMT3 inhibitor SGC707. Mechanism study shows that 11 induced global gene expression changes, including the activation of intrinsic apoptosis and endoplasmic reticulum stress signaling pathways, and the downregulation of E2F, MYC, oxidative phosphorylation pathways. Significantly, the combination of 11 and glycolysis inhibitor 2-DG has a notable synergistic antiproliferative effect by further reducing ATP production and inducing intrinsic apoptosis, thus further highlighting the potential therapeutic value of targeted PRMT3 degradation. These data clearly demonstrated that degrader 11 is a powerful chemical tool for investigating PRMT3 protein functions.

Matrix Protein of Vesicular Stomatitis Virus Targets the Mitochondria, Reprograms Glucose Metabolism, and Sensitizes to 2-Deoxyglucose in Glioblastoma

A potential therapeutic approach for cancer treatment is target oxidative phosphorylation and glycolysis simultaneously. The matrix protein of vesicular stomatitis virus (VSV MP) can target the surface of mitochondria, causing morphological changes that may be associated with mitochondrial dysfunction and oxidative phosphorylation inhibition. Previous research has shown that mitochondrial abnormalities can direct glucose metabolism toward glycolysis. Thus, after treatment with VSV MP, glycolysis inhibition is necessary to completely block glucose metabolism and eradicate cancer. Here, to inhibit glycolysis, the 2-deoxy-D-glucose (2-DG), a synthetic glucose analog was used to combine with VSV MP to treat cancer. This study aims to determine how VSV MP affects the glucose bioenergetic metabolism of cancer cells and to evaluate the synergistic effect of 2-DG when combined with VSV. Our results indicated that in U87 and C6 glioblastoma cell lines, VSV MP caused mitochondrial membrane potential loss, cytochrome c release, and glucose bioenergetics metabolism reprogramming. When combined with 2-DG, VSV MP synergistically aggravated cell viability, apoptosis, and G2/M phase arrest. Meanwhile, the combination therapy exacerbated ATP depletion, activated AMPK, and inhibited mammalian target of rapamycin signaling pathways. In addition, 2-DG treatment alone induced autophagy in glioblastoma cells; however, VSV MP inhibited the autophagy induced by 2-DG in combined treatment and finally contributed to the enhanced cytotoxic effect of the combination strategy in U87 and C6 cancer cells. In the orthotopic U87 glioblastoma model and subcutaneous C6 glioblastoma model, the combined treatment led to significant tumor regression and prolonged survival. A potent therapeutic approach for treating glioblastoma may be found in the combination of VSV MP and glycolytic inhibitors.

Targeting metabolic pathways to counter cancer immunotherapy resistance

Immunotherapies have revolutionized the treatment of certain cancers, but challenges remain in overcoming immunotherapy resistance. Research shows that metabolic modulation of the tumor microenvironment can enhance antitumor immunity. Here, we discuss recent preclinical and clinical evidence for the efficacy of combining metabolic modifiers with immunotherapies. While this combination holds great promise, a few key areas must be addressed, which include identifying the effects of metabolic modifiers on immune cell metabolism, the putative biomarkers of therapeutic efficacy, the efficacy of modifiers on tumors harboring metabolic heterogeneity, and the potential development of resistance due to tumor reliance on alternative metabolic pathways. We propose solutions to these problems and posit that assessing these parameters is crucial for considering the potential of metabolic modifiers in sensitizing tumors to immunotherapies.

Targeting cancer and immune cell metabolism with the complex I inhibitors metformin and IACS-010759

Metformin and IACS-010759 are two distinct antimetabolic agents. Metformin, an established antidiabetic drug, mildly inhibits mitochondrial complex I, while IACS-010759 is a new potent mitochondrial complex I inhibitor. Mitochondria is pivotal in the energy metabolism of cells by providing adenosine triphosphate through oxidative phosphorylation (OXPHOS). Hence, mitochondrial metabolism and OXPHOS become a vulnerability when targeted in cancer cells. Both drugs have promising antitumoral effects in diverse cancers, supported by preclinical in vitro and in vivo studies. We present evidence of their direct impact on cancer cells and their immunomodulatory effects. In clinical studies, while observational epidemiologic studies on metformin were encouraging, actual trial results were not as expected. However, IACS-01075 exhibited major adverse effects, thereby causing a metabolic shift to glycolysis and elevated lactic acid concentrations. Therefore, the future outlook for these two drugs depends on preventive clinical trials for metformin and investigations into the plausible toxic effects on normal cells for IACS-01075.

Single-cell and spatial transcriptomics reveal a high glycolysis B cell and tumor-associated macrophages cluster correlated with poor prognosis and exhausted immune microenvironment in diffuse large B-cell lymphoma

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous malignancy characterized by varied responses to treatment and prognoses. Understanding the metabolic characteristics driving DLBCL progression is crucial for developing personalized therapies.

METHODS

This study utilized multiple omics technologies including single-cell transcriptomics (n = 5), bulk transcriptomics (n = 966), spatial transcriptomics (n = 10), immunohistochemistry (n = 34), multiple immunofluorescence (n = 20) and to elucidate the metabolic features of highly malignant DLBCL cells and tumor-associated macrophages (TAMs), along with their associated tumor microenvironment. Metabolic pathway analysis facilitated by scMetabolism, and integrated analysis via hdWGCNA, identified glycolysis genes correlating with malignancy, and the prognostic value of glycolysis genes (STMN1, ENO1, PKM, and CDK1) and TAMs were verified.

RESULTS

High-glycolysis malignant DLBCL tissues exhibited an immunosuppressive microenvironment characterized by abundant IFN_TAMs (CD68+CXCL10+PD-L1+) and diminished CD8+ T cell infiltration. Glycolysis genes were positively correlated with malignancy degree. IFN_TAMs exhibited high glycolysis activity and closely communicating with high-malignancy DLBCL cells identified within datasets. The glycolysis score, evaluated by seven genes, emerged as an independent prognostic factor (HR = 1.796, 95% CI: 1.077-2.995, p = 0.025 and HR = 2.631, 95% CI: 1.207-5.735, p = 0.015) along with IFN_TAMs were positively correlated with poor survival (p < 0.05) in DLBCL. Immunohistochemical validation of glycolysis markers (STMN1, ENO1, PKM, and CDK1) and multiple immunofluorescence validation of IFN_TAMs underscored their prognostic value (p < 0.05) in DLBCL.

CONCLUSIONS

This study underscores the significance of glycolysis in tumor progression and modulation of the immune microenvironment. The identified glycolysis genes and IFN_TAMs represent potential prognostic markers and therapeutic targets in DLBCL.

Unraveling ETC complex I function in ferroptosis reveals a potential ferroptosis-inducing therapeutic strategy for LKB1-deficient cancers

The role of the mitochondrial electron transport chain (ETC) in regulating ferroptosis is not fully elucidated. Here, we reveal that pharmacological inhibition of the ETC complex I reduces ubiquinol levels while decreasing ATP levels and activating AMP-activated protein kinase (AMPK), the two effects known for their roles in promoting and suppressing ferroptosis, respectively. Consequently, the impact of complex I inhibitors on ferroptosis induced by glutathione peroxidase 4 (GPX4) inhibition is limited. The pharmacological inhibition of complex I in LKB1-AMPK-inactivated cells, or genetic ablation of complex I (which does not trigger apparent AMPK activation), abrogates the AMPK-mediated ferroptosis-suppressive effect and sensitizes cancer cells to GPX4-inactivation-induced ferroptosis. Furthermore, complex I inhibition synergizes with radiotherapy (RT) to selectively suppress the growth of LKB1-deficient tumors by inducing ferroptosis in mouse models. Our data demonstrate a multifaceted role of complex I in regulating ferroptosis and propose a ferroptosis-inducing therapeutic strategy for LKB1-deficient cancers.

CASi: A framework for cross-timepoint analysis of single-cell RNA sequencing data

Single-cell RNA sequencing (scRNA-seq) technology has been widely used to study the differences in gene expression at the single cell level, providing insights into the research of cell development, differentiation, and functional heterogeneity. Various pipelines and workflows of scRNA-seq analysis have been developed but few considered multi-timepoint data specifically. In this study, we develop CASi, a comprehensive framework for analyzing multiple timepoints' scRNA-seq data, which provides users with: (1) cross-timepoint cell annotation, (2) detection of potentially novel cell types emerged over time, (3) visualization of cell population evolution, and (4) identification of temporal differentially expressed genes (tDEGs). Through comprehensive simulation studies and applications to a real multi-timepoint single cell dataset, we demonstrate the robust and favorable performance of the proposal versus existing methods serving similar purposes.

Automatic subtyping of Diffuse Large B-cell Lymphomas (DLBCL): Raman-based genetic and metabolic classification

Diffuse large B-cell lymphoma (DLBCL), the most common non-Hodgkin's lymphoma in adults, is a genetically and metabolically heterogeneous group of aggressive malignancies. The complexity of their molecular composition and the variability in clinical presentation make clinical diagnosis and treatment selection a serious challenge. The challenge is therefore to quickly and correctly classify DLBCL cells. In this work, we show that Raman imaging is a tool with high diagnostic potential, providing unique information about the biochemical components of tumor cells and their metabolism. We present models of classification of lymphoma cells based on their Raman spectra. The models automatically and efficiently identify DLBCL cells and assign them to a given cell-of-origin (COO) subtype (activated B cell-like (ABC) or germinal center B cell-like (GCB)) or, respectively, to a comprehensive cluster classification (CCC) subtype (OxPhos/non-OxPhos). In addition, we describe each lymphoma subtype by its unique spectral profile, linking it to biochemical, genetic, or metabolic features.

Cryptotanshinone suppresses ovarian cancer via simultaneous inhibition of glycolysis and oxidative phosphorylation

Ovarian cancer is one of the most lethal cancers in female reproductive system due to heterogeneity and lack of effective treatment. Targeting aerobic glycolysis, a predominant energy metabolism of cancer cells has been recognized a novel strategy to overcome cancer cell growth. However, the capability of cancer cells to undergo metabolic reprogramming guarantees their survival even when glycolysis is inhibited. Here in this study, we have shown that Cryptotanshinone (CT), a lipid-soluble bioactive anticancer molecule of Salvia miltiorrhiza, inhibits both glycolysis and oxidative phosphorylation (OXPHOS) in ovarian cancer cells leading to growth suppression and apoptosis induction. Our mechanistic study revealed that CT decreased glucose uptake and lactate production, and inhibited the kinase activity of LDHA and HK2. The molecular docking study showed that CT could directly bind with GLUT1, LDHA, HK2, PKM2 and complex-1. The immunoblotting data showed that CT decreased the expression of aberrantly activated glycolytic proteins includingGLUT1, LDHA, HK2, and PKM2. Besides, we found that CT inhibited mitochondrial ComplexⅠ activity, decreased the ratio of NAD+/NADH, and suppressed the generation of ATP and induced activation of AMPK, which controls energy-reducing processes. These in vitro findings were further validated using xenograft model. The findings of in vivo studies were in line with in vitro studies. Taken together, CT effectively suppressed glycolysis and OXPHOS, inhibited growth and induced apoptosis in ovarian cancer cells both in vitro and in vivo study models.

Role of Human Monocarboxylate Transporter 1 (hMCT1) and 4 (hMCT4) in Tumor Cells and the Tumor Microenvironment

In recent years, the abnormal glucose metabolism of tumor cells has attracted increasing attention. Abnormal glucose metabolism is closely related to the occurrence and development of tumors. Monocarboxylate transporters (MCTs) transport the sugar metabolites lactic acid and pyruvate, which affect glucose metabolism and tumor progression in a variety of ways. Thus, research has recently focused on MCTs and their potential functions in cancer. The MCT superfamily consists of 14 members. MCT1 and MCT4 play a crucial role in the maintenance of intracellular pH in tumor cells by transporting monocarboxylic acids (such as lactate, pyruvate and butyrate). MCT1 and MCT4 are highly expressed in a variety of tumor cells and are involved the proliferation, invasion and migration of tumor cells, which are closely related to the prognosis of cancer. Because of their important functions in tumor cells, MCT1 and MCT4 have become potential targets for cancer treatment. In this review, we focus on the structure, function and regulation of MCT1 and MCT4 and discuss the developed inhibitors of MCT1 and MCT4 to provide more comprehensive information that might aid in the development of strategies targeting MCTs in cancer.

Antiproliferative effects of mitochondria-targeted N-acetylcysteine and analogs in cancer cells

N-acetylcysteine (NAC) has been used as an antioxidant drug in tumor cells and preclinical mice tumor xenografts, and it improves adaptive immunotherapy in melanoma. NAC is not readily bioavailable and is used in high concentrations. The effects of NAC have been attributed to its antioxidant and redox signaling role in mitochondria. New thiol-containing molecules targeted to mitochondria are needed. Here, mitochondria-targeted NAC with a 10-carbon alkyl side chain attached to a triphenylphosphonium group (Mito₁₀-NAC) that is functionally similar to NAC was synthesized and studied. Mito₁₀-NAC has a free sulfhydryl group and is more hydrophobic than NAC. Mito₁₀-NAC is nearly 2000-fold more effective than NAC in inhibiting several cancer cells, including pancreatic cancer cells. Methylation of NAC and Mito₁₀-NAC also inhibited cancer cell proliferation. Mito₁₀-NAC inhibits mitochondrial complex I-induced respiration and, in combination with monocarboxylate transporter 1 inhibitor, synergistically decreased pancreatic cancer cell proliferation. Results suggest that the antiproliferative effects of NAC and Mito₁₀-NAC are unlikely to be related to their antioxidant mechanism (i.e., scavenging of reactive oxygen species) or to the sulfhydryl group-dependent redox modulatory effects.

Aldose reductase and cancer metabolism: The master regulator in the limelight

It is strongly established that metabolic reprogramming mediates the initiation, progression, and metastasis of a variety of cancers. However, there is no common biomarker identified to link the dysregulated metabolism and cancer progression. Recent studies strongly advise the involvement of aldose reductase (AR) in cancer metabolism. AR-mediated glucose metabolism creates a Warburg-like effect and an acidic tumour microenvironment in cancer cells. Moreover, AR overexpression is associated with the impairment of mitochondria and the accumulation of free fatty acids in cancer cells. Further, AR-mediated reduction of lipid aldehydes and chemotherapeutics are involved in the activation of factors promoting proliferation and chemo-resistance. In this review, we have delineated the possible mechanisms by which AR modulates cellular metabolism for cancer proliferation and survival. An in-depth understanding of cancer metabolism and the role of AR might lead to the use of AR inhibitors as metabolic modulating agents for the therapy of cancer.

OXPHOS inhibitors, metabolism and targeted therapies in cancer

More and more studies highlight the complex metabolic characteristics and plasticity of cancer cells. To address these specificities and explore the associated vulnerabilities, new metabolism-targeting therapeutic strategies are being developed. It is more and more accepted that cancer cells do not produce their energy only from aerobic glycolysis, as some subtypes strongly rely on mitochondrial respiration (OXPHOS). This review focuses on classical and promising OXPHOS inhibitors (OXPHOSi), unravelling their interest and modes of actions in cancer, particularly in combination with other strategies. Indeed, in monotherapy, OXPHOSi display limited efficiency as they mostly trigger cell death in cancer cell subtypes that strongly depend on mitochondrial respiration and are not able to shift to other metabolic pathways to produce energy. Nevertheless, they remain very interesting in combination with conventional therapeutic strategies such as chemotherapy and radiotherapy, increasing their anti-tumoral actions. In addition, OXPHOSi can be included in even more innovative strategies such as combinations with other metabolic drugs or immunotherapies.

Metabolomics: A New Era in the Diagnosis or Prognosis of B-Cell Non-Hodgkin's Lymphoma

A wide range of histological as well as clinical properties are exhibited by B-cell non-Hodgkin's lymphomas. These properties could make the diagnostics process complicated. The diagnosis of lymphomas at an initial stage is essential because early remedial actions taken against destructive subtypes are commonly deliberated as successful and restorative. Therefore, better protective action is needed to improve the condition of those patients who are extensively affected by cancer when diagnosed for the first time. The development of new and efficient methods for early detection of cancer has become crucial nowadays. Biomarkers are urgently needed for diagnosing B-cell non-Hodgkin's lymphoma and assessing the severity of the disease and its prognosis. New possibilities are now open for diagnosing cancer with the help of metabolomics. The study of all the metabolites synthesised in the human body is called "metabolomics." A patient's phenotype is directly linked with metabolomics, which can help in providing some clinically beneficial biomarkers and is applied in the diagnostics of B-cell non-Hodgkin's lymphoma. In cancer research, it can analyse the cancerous metabolome to identify the metabolic biomarkers. This review provides an understanding of B-cell non-Hodgkin's lymphoma metabolism and its applications in medical diagnostics. A description of the workflow based on metabolomics is also provided, along with the benefits and drawbacks of various techniques. The use of predictive metabolic biomarkers for the diagnosis and prognosis of B-cell non-Hodgkin's lymphoma is also explored. Thus, we can say that abnormalities related to metabolic processes can occur in a vast range of B-cell non-Hodgkin's lymphomas. The metabolic biomarkers could only be discovered and identified as innovative therapeutic objects if we explored and researched them. In the near future, the innovations involving metabolomics could prove fruitful for predicting outcomes and bringing out novel remedial approaches.

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.

Monocarboxylate transporter 4 involves in energy metabolism and drug sensitivity in hypoxia

Metabolic reprogramming of cancer cells is a potential target for cancer therapy. It is also known that a hypoxic environment, one of the tumor microenvironments, can alter the energy metabolism from oxidative phosphorylation to glycolysis. However, the relationship between hypoxia and drug sensitivity, which targets energy metabolism, is not well known. In this study, A549 cells, a cell line derived from lung adenocarcinoma, were evaluated under normoxia and hypoxia for the sensitivity of reagents targeting oxidative phosphorylation (metformin) and glycolysis (α-cyano-4-hydroxycinnamic acid [CHC]). The results showed that a hypoxic environment increased the expression levels of monocarboxylate transporter (MCT) 4 and hypoxia-induced factor-1α (HIF-1α), whereas MCT1 and MCT2 expression did not vary between normoxia and hypoxia. Furthermore, the evaluation of the ATP production ratio indicated that glycolysis was enhanced under hypoxic conditions. It was then found that the sensitivity to metformin decreased while that to CHC increased under hypoxia. To elucidate this mechanism, MCT4 and HIF-1α were knocked down and the expression level of MCT4 was significantly decreased under both conditions. In contrast, the expression of HIF-1α was decreased by HIF-1α knockdown and increased by MCT4 knockdown. In addition, changes in metformin and CHC sensitivity under hypoxia were eliminated by the knockdown of MCT4 and HIF-1α, suggesting that MCT4 is involved in the phenomenon described above. In conclusion, it was shown that the sensitivity of reagents targeting energy metabolism is dependent on their microenvironment. As MCT4 is involved in some of these mechanisms, we hypothesized that MCT4 could be an important target molecule for cancer therapy.

A glycolysis-related gene signatures in diffuse large B-Cell lymphoma predicts prognosis and tumor immune microenvironment

Background: Diffuse large B-cell lymphoma (DLBCL) is the most common type of lymphoma which that highly aggressive and heterogeneous. Glycolysis has been implicated in the regulation of tumor microenvironment (TME) and development. In this study, we aimed to establish a glycolysis-related prognostic model for the risk stratification, prognosis prediction, and immune landscape evaluation in patients with DLBCL. Methods: Three independent datasets GSE181063, GSE10846, and GSE53786 containing gene expression profiles and clinical data were downloaded from the Gene Expression Omnibus (GEO) database. The glycolysis-related prognostic model was developed with Cox and Least Absolute Shrinkage and Selector Operation (LASSO) regression and validated. A nomogram integrating clinical factors and glycolytic risk scores was constructed. The composition of the TME was analyzed with the ESTIMATE algorithm and single-sample gene set enrichment analysis (ssGSEA). Results: A glycolytic risk model containing eight genes was developed. The area under the receiver operating characteristic (ROC) curve (AUC) for the 1-, 3-, and 5-year was 0.718, 0.695, and 0.688, respectively. Patients in the high-risk group had significantly lower immune scores, elevated tumor purity, and poorer survival compared with those in the low-risk group. The nomogram constructed based on glycolytic risk score, age, Eastern Cooperative Oncology Group performance status (ECOG-PS), use of rituximab, and cell of origin (COO) displayed better prediction performance compared with the International Prognostic Index (IPI) in DLBCL. The glycolytic risk score was negatively correlated with the infiltration level of activated CD8 T cells, activated dendritic cells, natural killer cells, and macrophages and immune checkpoint molecules including PD-L2, CTLA4, TIM-3, TIGIT, and B7-H3. Conclusion: These results suggested that the glycolytic risk model could accurately and stably predict the prognosis of patients with DLBCL and might unearth the possible explanation for the glycolysis-related poor prognosis.

Current Status of Novel Agents for the Treatment of B Cell Malignancies: What's Coming Next?

Resistance to death is one of the hallmarks of human B cell malignancies and often contributes to the lack of a lasting response to today's commonly used treatments. Drug discovery approaches designed to activate the death machinery have generated a large number of inhibitors of anti-apoptotic proteins from the B-cell lymphoma/leukemia 2 family and the B-cell receptor (BCR) signaling pathway. Orally administered small-molecule inhibitors of Bcl-2 protein and BCR partners (e.g., Bruton's tyrosine kinase and phosphatidylinositol-3 kinase) have already been included (as monotherapies or combination therapies) in the standard of care for selected B cell malignancies. Agonistic monoclonal antibodies and their derivatives (antibody-drug conjugates, antibody-radioisotope conjugates, bispecific T cell engagers, and chimeric antigen receptor-modified T cells) targeting tumor-associated antigens (TAAs, such as CD19, CD20, CD22, and CD38) are indicated for treatment (as monotherapies or combination therapies) of patients with B cell tumors. However, given that some patients are either refractory to current therapies or relapse after treatment, novel therapeutic strategies are needed. Here, we review current strategies for managing B cell malignancies, with a focus on the ongoing clinical development of more effective, selective drugs targeting these molecules, as well as other TAAs and signaling proteins. The observed impact of metabolic reprogramming on B cell pathophysiology highlights the promise of targeting metabolic checkpoints in the treatment of these disorders.

Advances in Understanding of Metabolism of B-Cell Lymphoma: Implications for Therapy

There have been significant recent advances in the understanding of the role of metabolism in normal and malignant B-cell biology. Previous research has focused on the role of MYC and mammalian target of rapamycin (mTOR) and how these interact with B-cell receptor signaling and hypoxia to regulate glycolysis, glutaminolysis, oxidative phosphorylation (OXPHOS) and related metabolic pathways in germinal centers. Many of the commonest forms of lymphoma arise from germinal center B-cells, reflecting the physiological attenuation of normal DNA damage checkpoints to facilitate somatic hypermutation of the immunoglobulin genes. As a result, these lymphomas can inherit the metabolic state of their cell-of-origin. There is increasing interest in the potential of targeting metabolic pathways for anti-cancer therapy. Some metabolic inhibitors such as methotrexate have been used to treat lymphoma for decades, with several new agents being recently licensed such as inhibitors of phosphoinositide-3-kinase. Several other inhibitors are in development including those blocking mTOR, glutaminase, OXPHOS and monocarboxylate transporters. In addition, recent work has highlighted the importance of the interaction between diet and cancer, with particular focus on dietary modifications that restrict carbohydrates and specific amino acids. This article will review the current state of this field and discuss future developments.

GAPDH in neuroblastoma: Functions in metabolism and survival

Neuroblastoma is a pediatric cancer of neural crest cells. It develops most frequently in nerve cells around the adrenal gland, although other locations are possible. Neuroblastomas rely on glycolysis as a source of energy and metabolites, and the enzymes that catalyze glycolysis are potential therapeutic targets for neuroblastoma. Furthermore, glycolysis provides a protective function against DNA damage, and there is evidence that glycolysis inhibitors may improve outcomes from other cancer treatments. This mini-review will focus on glyceraldehyde 3-phosphate dehydrogenase (GAPDH), one of the central enzymes in glycolysis. GAPDH has a key role in metabolism, catalyzing the sixth step in glycolysis and generating NADH. GAPDH also has a surprisingly diverse number of localizations, including the nucleus, where it performs multiple functions, and the plasma membrane. One membrane-associated function of GAPDH is stimulating glucose uptake, consistent with a role for GAPDH in energy and metabolite production. The plasma membrane localization of GAPDH and its role in glucose uptake have been verified in neuroblastoma. Membrane-associated GAPDH also participates in iron uptake, although this has not been tested in neuroblastoma. Finally, GAPDH activates autophagy through a nuclear complex with Sirtuin. This review will discuss these activities and their potential role in cancer metabolism, treatment and drug resistance.