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Recent studies have shown that Solute Carrier Family 9 Member A2 (SLC9A2) could serve as a biomarker for cancer. However, its mechanism of action in osteosarcoma (OS) was still unclear. In this study, the data sets GSE154530 and GSE99671 were downloaded from the Gene Expression Omnibus (GEO) database, and 31 differentially expressed genes (DEGs) related to methylation were screened by bioinformatics analysis tools. Subsequently, SLC9A2 was screened as a candidate gene from DEGs, which was significantly downregulated in OS. CCK‐8, transwell, western blotting and Seahorse XFe24 Cell Metabolic Analyzer assays demonstrated that overexpression of SLC9A2 could constrain OS cell proliferation, invasion, and aerobic glycolysis. Dual‐luciferase reporter gene assay and chromatin immunoprecipitation (ChIP) assays indicated ETS proto‐oncogene 1 (ETS1) was a transcription suppressor of SLC9A2, and overexpression of ETS1 could promote methylation levels in specific regions of the SLC9A2 promoter. ETS1 could promote the proliferation, invasion, and aerobic glycolysis ability of OS cells, as well as tumor growth in vivo by inhibiting the expression of SLC9A2. In addition, SLC9A2, suppressing by ETS1, restrains growth and invasion of OS via inhibition of aerobic glycolysis. Thus, SLC9A2 can function as a key inhibitory factor in the aerobic glycolysis to inhibit proliferation and invasion of OS. This indicated that SLC9A2 has a potential targeted therapeutic effect on OS. [ABSTRACT FROM AUTHOR]

Introduction: The majority of individuals diagnosed with advanced colorectal cancer (CRC) will ultimately acquire resistance to 5-FU treatment. An increasing amount of evidence indicates that aerobic glycolysis performs a significant function in the progression and resistance of CRC. Nevertheless, the fundamental mechanisms remain to be fully understood. Methods: Proteomic analysis of 5-FU resistant CRC cells was implemented to identify and determine potential difference expression protein. Results: These proteins may exhibit resistance mechanisms that are potentially linked to the process of aerobic glycolysis. Herein, we found that nucleolar protein 58 (NOP58) has been overexpressed within two 5-FU resistant CRC cells, 116- 5FuR and Lovo-5FuR. Meanwhile, the glycolysis rate of drug-resistant cancer cells has increased. NOP58 knockdown decreased glycolysis and enhanced the sensitivity of 116-5FuR and Lovo-5FuR cells to 5FU. Conclusion: The proteomic analysis of chemoresistance identifies a new target involved in the cellular adaption to 5-FU and therefore highlights a possible new therapeutic strategy to overcome this resistance. [ABSTRACT FROM AUTHOR]

Proliferating cells have increased mitochondrial activity relative to quiescent cells. Metabolic pathways in mitochondria are saturated in proliferating cells exhibiting the Warburg effect. Mitochondrial activity is constrained by the flux of NAD+ turnover in proliferating cells. The Warburg effect occurs in proliferating cells because glycolysis outpaces the maximum rate of glucose oxidation. A long-standing question in cancer biology has been why oxygenated tumors ferment the majority of glucose they consume to lactate rather than oxidizing it in their mitochondria, a phenomenon known as the 'Warburg effect.' An abundance of evidence shows not only that most cancer cells have fully functional mitochondria but also that mitochondrial activity is important to proliferation. It is therefore difficult to rationalize the metabolic benefit of cancer cells switching from respiration to fermentation. An emerging perspective is that rather than mitochondrial metabolism being suppressed in tumors, as is often suggested, mitochondrial activity increases to the level of saturation. As such, the Warburg effect becomes a signature of excess glucose being released as lactate due to mitochondrial overload. [ABSTRACT FROM AUTHOR]

Osteosarcoma (OS) is one of the most aggressive bone tumors worldwide. Emerging documents have shown that long noncoding RNAs (lncRNAs) elicit crucial regulatory functions in the process of tumorigenesis. LncRNA DLGAP1‐AS2 is recognized as a regulator in several types of cancers, but its biological functions and molecular mechanisms in OS remain to be elucidated. RT‐qPCR and In situ hybridization (ISH) were used to evaluate DLGAP1‐AS2 expression in OS samples. Western blotting was used for the measurement of the protein levels of hexokinase 2 (HK2) and epithelial–mesenchymal transition (EMT)‐related markers. The proliferation of OS cells was determined using a CCK‐8 assay and EdU assay. TUNEL assay and flow cytometry were performed to assess OS cell apoptosis. Glucose metabolism in vitro assays were used. The binding relations among miR‐451a, HK2, and DLGAP1‐AS2 were validated by luciferase reporter assay. The cellular distribution of DLGAP1‐AS2 in OS cells was determined by FISH and subcellular fractionation assays. Mouse xenograft models were established to perform the experiments in vivo. We found that DLGAP1‐AS2 expression was upregulated in OS tissues and cells. Downregulation of DLGAP1‐AS2 expression suppressed the malignancy of OS cells by restraining cell proliferation, the EMT process, invasiveness, migration, and aerobic glycolysis and accelerating apoptotic behaviors. Of note, silenced DLGAP1‐AS2 restrained tumor growth and metastasis in vivo. However, DLGAP1‐AS2 overexpression accelerated the progression of OS. We further found that DLGAP1‐AS2 upregulation was induced by hypoxia and low glucose. Additionally, DLGAP1‐AS2 bound to miR‐451a to upregulate HK2 expression. Rescue assays revealed that the DLGAP1‐AS2/miR‐451a/HK2 axis contributed to OS cell malignancy by promoting aerobic glucose metabolism. Overall, these findings revealed a new regulatory pathway where DLGAP1‐AS2 upregulated HK2 expression by sponging miR‐451a to accelerate OS development. [ABSTRACT FROM AUTHOR]

Secondary diabetes mellitus (DM) in secretory pheochromocytomas and paragangliomas (PPGLs) is encountered in up to 50% of cases, with its presentation ranging from mild, insulin resistant forms to profound insulin deficiency states, such as diabetic ketoacidosis and hyperglycemic hyperosmolar state. PPGLs represent hypermetabolic states, in which adrenaline and noradrenaline induce insulin resistance in target tissues characterized by aerobic glycolysis, excessive lipolysis, altered adipokine expression, subclinical inflammation, as well as enhanced gluconeogenesis and glucogenolysis. These effects are mediated both directly, upon adrenergic receptor stimulation, and indirectly, via increased glucagon secretion. Impaired insulin secretion is the principal pathogenetic mechanism of secondary DM in this setting; yet, this is relevant for tumors with adrenergic phenotype, arising from direct inhibitory actions in beta pancreatic cells and incretin effect impairment. In contrast, insulin secretion might be enhanced in tumors with noradrenergic phenotype. This dimorphic effect might correspond to two distinct glycemic phenotypes, with predominant insulin resistance and insulin deficiency respectively. Secondary DM improves substantially post-surgery, with up to 80% remission rate. The fact that surgical treatment of PPGLs restores insulin sensitivity and secretion at greater extent compared to alpha and beta blockade, implies the existence of further, non-adrenergic mechanisms, possibly involving other hormonal co-secretion by these tumors. DM management in PPGLs is scarcely studied. The efficacy and safety of newer anti-diabetic medications, such as glucagon-like peptide 1 receptor agonists and sodium glucose cotransporter 2 inhibitors (SGLT2is), as well as potential disease-modifying roles of metformin and SGLT2is warrant further investigation in future studies. [ABSTRACT FROM AUTHOR]

Abstract Indoleamine 2,3‐dioxygenase 1 (IDO1), the key enzyme in the catabolism of the essential amino acid tryptophan (Trp) through kynurenine pathway, induces immune tolerance and is considered as a critical immune checkpoint, but its impacts as a metabolism enzyme on glucose and lipid metabolism are overlooked. We aim to clarify the potential role of IDO1 in aerobic glycolysis in pancreatic cancer (PC). Analysis of database revealed the positive correlation in PC between the expressions of IDO1 and genes encoding important glycolytic enzyme hexokinase 2 (HK2), pyruvate kinase (PK), lactate dehydrogenase A (LDHA) and glucose transporter 1 (GLUT1). It was found that IDO1 could modulate glycolysis and glucose uptake in PC cells, Trp deficiency caused by IDO1 overexpression enhanced glucose uptake by stimulating GLUT1 translocation to the plasma membrane of PC cells. Besides, Trp deficiency caused by IDO1 overexpression suppressed the apoptosis of PC cells via promoting glycolysis, which reveals the presence of IDO1–glycolysis–apoptosis axis in PC. IDO1 inhibitors could inhibit glycolysis, promote apoptosis, and exhibit robust therapeutic efficacy when combined with GLUT1 inhibitor in PC mice. Our study reveals the function of IDO1 in the glucose metabolism of PC and provides new insights into the therapeutic strategy for PC.

The retina consumes massive amounts of energy, yet its metabolism and substrate exploitation remain poorly understood. Here, we used a murine explant model to manipulate retinal energy metabolism under entirely controlled conditions and utilised 1H-NMR spectroscopy-based metabolomics, in situ enzyme detection, and cell viability readouts to uncover the pathways of retinal energy production. Our experimental manipulations resulted in varying degrees of photoreceptor degeneration, while the inner retina and retinal pigment epithelium were essentially unaffected. This selective vulnerability of photoreceptors suggested very specific adaptations in their energy metabolism. Rod photoreceptors were found to rely strongly on oxidative phosphorylation, but only mildly on glycolysis. Conversely, cone photoreceptors were dependent on glycolysis but insensitive to electron transport chain decoupling. Importantly, photoreceptors appeared to uncouple glycolytic and Krebs-cycle metabolism via three different pathways: (1) the mini-Krebs-cycle, fuelled by glutamine and branched chain amino acids, generating N-acetylaspartate; (2) the alanine-generating Cahill-cycle; (3) the lactate-releasing Cori-cycle. Moreover, the metabolomics data indicated a shuttling of taurine and hypotaurine between the retinal pigment epithelium and photoreceptors, likely resulting in an additional net transfer of reducing power to photoreceptors. These findings expand our understanding of retinal physiology and pathology and shed new light on neuronal energy homeostasis and the pathogenesis of neurodegenerative diseases.

Abstract Background Long noncoding RNAs (lncRNAs) have been reported to play vital roles in the development and progression of cancer. However, their biological significance and functional mechanisms in non-small cell lung cancer (NSCLC) are mostly unclear. Methods We performed RNA-sequencing to predict the differential expression of lncRNAs in clinical NSCLC and paired paracancerous lung tissues. To identify lncRNA expression, quantitative polymerase chain reaction (qPCR) was used. Using both cell and mouse models, We studied lncRNA AC016727.1’s function in NSCLC growth and metastasis. Western blot assays, dual luciferase reporter assays, and chromatin immunoprecipitation were used to analyze the functional mechanism of lncRNA AC016727.1. Results Our larger NSCLC cohorts validated that the lncRNA AC016727.1 was upregulated in 94 paired NSCLC tissues and correlated with poor survival. Functionally, lncRNA AC016727.1 downregulation inhibited NSCLC cell proliferation, aerobic glycolysis, EMT, and migration, inducing apoptosis. Conversely, upregulated lncRNA AC016727.1 expression exhibited the opposite effect, promoting NSCLC cell survival. Importantly, lncRNA AC016727.1 knockdown inhibited lung cancer growth and slowed the progression of lung metastasis in nude mouse models. Mechanistically, lncRNA AC016727.1 upregulated BACH1 target gene expression by acting as a sponge for miR-98-5p, thereby functioning as a competing endogenous RNA. The function of lncRNA AC016727.1 is mediated by the miR-98-5p/BACH1 axis in NSCLC cells. Meanwhile, the transcription factor HIF-1α can bind to the promoter and activate lncRNA AC016727.1 transcription. lncRNA AC016727.1 regulates HIF-1α expression via BACH1 in NSCLC and forms the lncRNA AC016727.1/BACH1/HIF-1α signaling loop under hypoxic conditions. Conclusion Our study reveals a novel lncRNA AC016727.1/BACH1/HIF-1α signaling loop in the progression of NSCLC under hypoxic conditions, suggesting that lncRNA AC016727.1 could act as a useful biomarker for NSCLC and a new therapeutic target.

The dysregulation of energetic metabolism is one of the hallmarks of cancer cells. Indeed, the growth of head and neck squamous cell carcinoma (HNSCC) cells depends heavily on glycolytic activity, which can be considered a potential therapeutic target. Wnt signaling is one of the pathways that undergoes upregulation in HNSCC. Our previous studies have shown that Wnt signaling inhibitors—PRI-724 and IWP-O1—attenuate tongue SCC survival and reduce glucose uptake and lactate release. The aim of this research was to further evaluate the possible mechanisms of the previously observed effects. We assessed the effect of PRI-724 and IWP-O1 on the expression of selected glycolytic enzymes: phosphofructokinase M, pyruvate kinase M2, and lactate dehydrogenase. Relative transcript expression was assessed by real-time PCR, and protein levels by Western blot. Moreover, clinical data concerning mRNA and protein expression, gene promoter methylation, and HNSCC patients’ survival time were analyzed by the UALCAN tool, and protein–protein interaction was assessed using the STRING database. Experimental and bioinformatic data confirmed the relation between Wnt signaling and glycolytic enzymes in tongue cancer cells and HNSCC clinical samples. Overall, the inhibition of glucose metabolism by Wnt signaling inhibitors is a promising mode of action against tongue cancer cells.

Abstract Background Emerging evidence indicates that circular RNAs (circRNAs) play vital roles in tumor progression, including lung adenocarcinomas (LUAD). However, the mechanisms by which circRNAs promote the progression of LUAD still require further investigation. Methods Quantitative real-time PCR was performed to detect the expression of circP4HB in LUAD tissues and cells. Then, Kaplan–Meier analysis was used to determine the prognostic value of circP4HB expression. We employed RNA pull-down, RNA immunoprecipitation, mass spectrometry, cells fraction, glucose consumption, lactate production, pyruvate kinase M2 (PKM2) activity, and macrophage polarization assays to uncover the underlying mechanisms of circP4HB in LUAD. Results We found that circP4HB is upregulated in LUAD tissues and correlated with advanced TNM stages and lymph node metastasis. LUAD patients with high circP4HB expression had poor prognoses. Functionally, circP4HB promoted LUAD progression in vivo and in vitro. Upregulated circP4HB increased glucose consumption, lactate production and accelerated aerobic glycolysis in LUAD cells. Mechanically, circP4HB mainly accumulated in the cytoplasm of LUAD cells and bound with PKM2 and subsequently upregulating PKM2 enzymatic activity by increasing its tetramer formation. Additionally, circP4HB promoted M2 macrophage phenotype shift via targeting PKM2. Finally, rescue assays further confirmed that circP4HB could promote LUAD cell progression through its interaction with PKM2. Conclusion These results demonstrate that circP4HB could promote LUAD progression, indicating circP4HB might be a potential therapeutic target of LUAD. Graphical Abstract

Abstract Background Despite improvements in prognosis due to advances in treatment, including surgery, genetic screening, and molecular targeted therapy, the outcomes of ovarian cancer (OC) remain unsatisfactory. Internal mRNA modifications are extremely common in eukaryotes; N6-methyladenosine (m6A) alteration has significant effects on mRNA stability and translation, and it is involved in the pathophysiology of numerous diseases related to cancer. Methods Bioinformatics analysis, quantitative real-time polymerase chain reaction and Western blotting were used to detect the expression of vir-like m6A methyltransferase associated (KIAA1429) in OC tissues and cell lines. Several different cell models and animal models were established to determine the role of KIAA1429 in glucose metabolism reprogramming and the underlying molecular mechanism of OC. The mechanism of oncology functional assays, co-immunoprecipitation and a luciferase reporter gene was employed to ascertain how KIAA1429 interacts with important molecular targets. Results We reported that KIAA1429 was overexpressed in OC and predicted a poor prognosis. Functionally, KIAA1429 promoted cell growth by inducing proliferation and inhibiting necrosis. Mechanistically, KIAA1429 promoted tumor progression and glycolysis via stabilizing ENO1 mRNA in a way dependent on m6A. Furthermore, we investigated that the SPI1 transcription factor is the main transcription factor that regulates KIAA1429 transcription in OC. Conclusion Our findings revealed that SPI1/KIAA1429/ENO1 signaling is a novel molecular axis and raises awareness of the vital functions of the changes in KIAA1429 and m6A changes in the metabolic reprogramming of OC. These results identified new potential biomarkers and treatment targets for OC.

Abstract Background Replication factor C subunit 2 (RFC2) participates in the growth and metastasis of various malignancies. Our study investigated the roles of RFC2 in colorectal cancer (CRC). Results RFC2 expression was upregulated in CRC tissues and cells. High RFC2 expression was associated with poor prognosis. Knockdown RFC2 inhibited proliferation, induced apoptosis, and suppressed migration and invasion of CRC cells. CREB5 was a transcription factor of RFC2, and CREB5 knockdown suppressed RFC2 expression. Furthermore, RFC2 promoted aerobic glycolysis and MET/PI3K/AKT/mTOR pathway. Conclusion RFC2 promoted the progression of CRC cells via activating aerobic glycolysis and the MET/PI3K/AKT/mTOR pathway.

AP000695.2 is a novel long non-coding RNA (lncRNA). Its aberrant high expression is remarkably associated with poor prognosis of patients with lung adenocarcinoma (LUAD). However, its role and underlying mechanism in LUAD remains unclear. Previous bioinformatics analysis indicated that AP000695.2 may be closely related to the glycolysis of LUAD. This study aims to verify and explore the mechanism of AP000695.2 in glycolysis of LUAD. Overexpression plasmid and siRNA are used to construct cell models of upregulation and downregulation of AP000695.2, respectively. AP000695.2 is highly expressed in lung cancer cell lines as revealed by qPCR. Western blot analysis, FDG uptake, lactate production assay and ECAR determination results show that high expression of AP000695.2 facilitates glycolysis of LUAD cells. CCK-8, EdU staining, Transwell and wound healing assays show that high expression of AP000695.2 promotes cell growth and migration of LUAD. The relationship between AP000695.2 and miR-335-3p is confirmed by bioinformatics analysis and dual-luciferase reporter assays. Through the dual-luciferase reporter assay, TEA domain transcription factor 1 (TEAD1) is identified as a target gene of miR-335-3p. Rescue experiments are applied to verify the relationship among AP000695.2, miR-335-3p and TEAD1. Our study indicates that AP000695.2 is involved in the mechanism of LUAD through functioning as a ceRNA to competitively sponge miR-335-3p, thereby regulating the expression of TEAD1. In the in vivo models, AP000695.2 depletion restrains tumor growth and glycolysis. AP000695.2 promotes the glycolysis of LUAD by regulating the miR-335-3p/TEAD1 axis, and it may serve as a potential target of anti-tumor energy metabolism therapy.

Abstract Background Age-associated changes in immunity are inextricably linked to chronic inflammation and age-related diseases, the impact of aging on monocyte subsets is poorly understood. Methods Flow cytometry was applied to distinguish three monocyte subsets between 120 young and 103 aged individuals. We then analyzed the expression profiles of three monocyte subsets from 9 young and 9 older donors and CD14+ monocytes from 1202 individuals between 44 and 83 years old. Flow cytometry was used to measure β-galactosidase activities, ROS levels, mitochondrial contents, mitochondrial membrane potentials (MMPs) and intracellular IL-6 levels in three monocyte subsets of young and elderly individuals, and plasma IL-6 levels were detected by electrochemiluminescence immunoassay. Mitochondrial stress and glycolytic rate of CD14+ monocytes from young and aged individuals were measured by Seahorse XFe24 Analyzer. Results Compared with young individuals, the percentage of classical subset in aged persons significantly decreased, while the proportion of nonclassical subset increased. Age-related differential genes were obviously enriched in cellular senescence, ROS, oxidative phosphorylation, mitochondrial respiratory chain, IL-6 and ribosome-related pathways. Compared with young individuals, the β-galactosidase activities, ROS contents, intracellular IL-6 levels of three monocyte subsets, and plasma IL-6 levels in aged individuals were significantly elevated, while the MMPs apparently declined with age and the mitochondrial contents were only increased in intermediate and nonclassical subsets. CD14+ monocytes from elderly adults had conspicuously lower basal and spare respiratory capacity and higher basal glycolysis than those from young individuals. Conclusions During aging, monocytes exhibited senescence-associated secretory phenotype, mitochondrial dysfunction, decreased oxidative phosphorylation and increased glycolysis and the nonclassical subset displayed the clearest features of aging. Our study comprehensively investigated age-related transcriptional alterations of three monocyte subsets and identified the pivotal pathways of monocyte senescence, which may have significant implications for tactics to alleviate age-related conditions.

The Warburg effect (or aerobic glycolysis), which was first described in 1926 by Otto Heinrich Warburg, consists of the change in glucose metabolism in cancer cells. In normal cells, glucose metabolism finalizes in the mitochondria through oxidative phosphorylation (OXPHOS) in the presence of oxygen. However, the Warburg effect describes a change in the glucose metabolism in cancer cells, consuming excess glucose and converting it into lactate independently of the presence of oxygen. During this process, a wide variety of enzymes can modify their expression and activity to contribute to the mechanism of deregulated cancer metabolism. Therefore, the modulation of enzymes regulating aerobic glycolysis is a strategy for cancer treatment. Although numerous enzymes play a role in regulating aerobic glycolysis, hexokinase 2 (HK2), pyruvate dehydrogenase kinase (PDK), pyruvate kinase (PK), and lactate dehydrogenase (LDH) are worth mentioning. Numerous modulators of these enzymes have been described in recent years. This review aims to present and group, according to their chemical structure, the most recent emerging molecules targeting the above-mentioned enzymes involved in the Warburg effect in view of the future development of cancer treatments.

Abstract Cells that undergo normal differentiation mainly rely on mitochondrial oxidative phosphorylation to provide energy, but most tumour cells rely on aerobic glycolysis. This phenomenon is called the "Warburg effect". Phosphoglycerate kinase 1 (PGK1) is a key enzyme in aerobic glycolysis. PGK1 is involved in glucose metabolism as well as a variety of biological activities, including angiogenesis, EMT, mediated autophagy initiation, mitochondrial metabolism, DNA replication and repair, and other processes related to tumorigenesis and development. Recently, an increasing number of studies have proven that PGK1 plays an important role in cancer. In this manuscript, we discussed the effects of the structure, function, molecular mechanisms underlying PGK1 regulation on the initiation and progression of cancer. Additionally, PGK1 is associated with chemotherapy resistance and prognosis in tumour patients. This review presents an overview of the different roles played by PGK1 during tumorigenesis, which will help in the design of experimental studies involving PGK1 and enhance the potential for the use of PGK1 as a therapeutic target in cancer. Video Abstract

Objective To investigate the effects of microRNA-21 (miR-21) on proliferation, apoptosis and aerobic clycolysis of pancreatic cancer cells and its possible mechanism. Methods Human pancreatic cancer cell SW1990 and normal pancreatic duct epithelial cell HPDE were taken as research objects. SW1990 cells were transfected and divided into miR-NC group (transfected with miR-NC) and miR-21-minic group (transfected with miR-21-minic). MTT and clone formation assay were used to detect cell proliferation ability. Flow cytometry was used to detect cell apoptosis. RT-qPCR was used to detect the mRNA expression levels of miR-21 and pyruvate kinase M2 (PKM2) in cells. Western blot was used to detect PKM2 protein level. The luciferase reporter assay was used to detect the targeting relationship between miR-21 and PKM2. Results The expression level of miR-21 in SW1990 cells was higher than that in HPDE cells (0.79±0.02 vs 0.23±0.02, t =34.290, P＜0.01), while the expression levels of PKM2 protein (0.41±0.03) and mRNA (0.62±0.02) in SW1990 cells were lower than those in HPDE cells (0.95±0.02, 1.13±0.03, t =25.940, 24.500, P＜0.01). At 72 and 96 hours, the cell proliferation ability and number of clones cell in the miR-21-minic group were significantly higher than those in the miR-NC group, while the number of apoptotic cells was lower than that in the miR-NC group (P＜0.05). The glucose consumption, and the content of lactate, hexokinase (HK) and lactate dehydrogenase (LDH) in miR-21-mimic group were significantly higher than those in miR-NC group ( t =5.992, 21.340, 5.643, 4.008, P＜0.05). The level of PKM2 protein in the miR-21 mic group was lower than that in the miR-NC group ( t =10.070, P＜0.01). There were a certain number of complementary base pairs between miR-21 and WT-3′ UTR-PKM2, and the cell luciferase activity of miR-21-minic+WT-PKM2 group was lower than that of the transfected miR-NC+WT-PKM2 group ( t =15.680, P＜0.01). Conclusion The overexpression of miR-21 in pancreatic cancer cells may promote the proliferation, aerobic glycolysis, and inhibit apoptosis of pancreatic cancer cells. The mechanism may be related to targeting PKM2.

Abstract Background Renal cell carcinoma (RCC) is a hypermetabolic disease. Abnormal up-regulation of glycolytic signaling promotes tumor growth, and glycolytic metabolism is closely related to immunotherapy of renal cancer. The aim of the present study was to determine whether and how the glycolysis-related biomarker TCIRG1 affects aerobic glycolysis, the tumor microenvironment (TME) and malignant progression of clear cell renal cell carcinoma (ccRCC). Methods Based on The Cancer Genome Atlas (TCGA, n = 533) and the glycolysis-related gene set from MSigDB, we identified the glycolysis-related gene TCIRG1 by bioinformatics analysis, analyzed its immunological properties in ccRCC and observed how it affected the biological function and glycolytic metabolism using online databases such as TIMER 2.0, UALCAN, LinkedOmics and in vitro experiments. Results It was found that the expression of TCIRG1, was significantly increased in ccRCC tissue, and that high TCIRG1 expression was associated with poor overall survival (OS) and short progression-free interval (PFI). In addition, TCIRG1 expression was highly correlated with the infiltration immune cells, especially CD4+T cell Th1, CD8+T cell, NK cell, and M1 macrophage, and positively correlated with PDCD1, CTLA4 and other immunoinhibitors, CCL5, CXCR3 and other chemokines and chemokine receptors. More importantly, TCIRG1 may regulate aerobic glycolysis in ccRCC via the AKT/mTOR signaling pathway, thereby affecting the malignant progression of ccRCC cell lines. Conclusions Our results demonstrate that the glycolysis-related biomarker TCIRG1 is a tumor-promoting factor by affecting aerobic glycolysis and tumor immune microenvironment in ccRCC, and this finding may provide a new idea for the treatment of ccRCC by combination of metabolic intervention and immunotherapy.

Background Hepatic stellate cells (HSCs) are the major cells which play a pivotal role in liver fibrosis. During injury, extracellular stimulators can induce HSCs transdifferentiated into active form. Phloretin showed its ability to protect the liver from injury, so in this research we would like to investigate the effect of phloretin on succinate-induced HSCs activation in vitro and liver fibrosis in vivo study. Methods In in vitro, succinate was used to induce HSCs activation, and then the effect of phloretin on activated HSCs was examined. In in vivo, succinate was used to generated liver fibrosis in mouse and phloretin co-treated to check its protection on the liver. Results Phloretin can reduce the increase of fibrogenic markers and inhibits the proliferation, migration, and contraction caused by succinate in in vitro experiments. Moreover, an upregulation of proteins associated with aerobic glycolysis occurred during the activation of HSCs, which was attenuated by phloretin treatment. In in vivo experiments, intraperitoneal injection of phloretin decreased expression of fibrotic and glycolytic markers in the livers of mice with sodium succinate diet-induced liver fibrosis. These results suggest that aerobic glycolysis plays critical role in activation of HSCs and succinate can induce liver fibrosis in mice, whereas phloretin has therapeutic potential for treating hepatic fibrosis. Conclusion Intraperitoneal injection of phloretin attenuated succinate-induced hepatic fibrosis and alleviates the succinate-induced HSCs activation.

Abstract Purpose The oncoprotein KAI1 C-terminal interacting tetraspanin (KITENIN; vang-like 1) promotes cell metastasis, invasion, and angiogenesis, resulting in shorter survival times in cancer patients. Here, we aimed to determine the effects of KITENIN on the energy metabolism of human colorectal cancer cells. Experimental design The effects of KITENIN on energy metabolism were evaluated using in vitro assays. The GEPIA web tool was used to extrapolate the clinical relevance of KITENIN in cancer cell metabolism. The bioavailability and effect of the disintegrator of KITENIN complex compounds were evaluated by LC–MS, in vivo animal assay. Results KITENIN markedly upregulated the glycolytic proton efflux rate and aerobic glycolysis by increasing the expression of GLUT1, HK2, PKM2, and LDHA. β-catenin, CD44, CyclinD1 and HIF-1A, including c-Myc, were upregulated by KITENIN expression. In addition, KITENIN promoted nuclear PKM2 and PKM2-induced transactivation, which in turn, increased the expression of downstream mediators. This was found to be mediated through an effect of c-Myc on the transcription of hnRNP isoforms and a switch to the M2 isoform of pyruvate kinase, which increased aerobic glycolysis. The disintegration of KITENIN complex by silencing the KITENIN or MYO1D downregulated aerobic glycolysis. The disintegrator of KITENIN complex compound DKC1125 and its optimized form, DKC-C14S, exhibited the inhibition activity of KITENIN-mediated aerobic glycolysis in vitro and in vivo. Conclusions The oncoprotein KITENIN induces PKM2-mediated aerobic glycolysis by upregulating the c-Myc/hnRNPs axis.

Background and purpose: Methyltransferase Wilms’ tumor 1-associating protein (WTAP) has been proven to play an important role in the development of tumors. This study aimed to explore the influence of WTAP on the occurrence and development of glioma from the perspective of N6-methyladenosine (m6A) modification. Methods: The differentially expressed m6A regulators in glioma were screened from GEO database. The expression of WTAP/B cell-specific Moloney murine leukemia virus integration site 1 (BMI1) in glioma tissue and cell lines was evaluated by real-time fluorescence quantitative polymerase chain reaction (RTFQ-PCR) and Western blot. Methyl thiazoyl terazolium (MTT) was used to explore the effects of WTAP/BMI1 on glioma cell proliferation. Extracellular acidification rate (ECAR) kits and glucose consumption and lactate production detection kits were utilized to detect aerobic glycolysis of glioma cells. Results: Compared with normal tissues, WTQP and BMI1 expressions were upregulated in glioma tissues. Otherwise, compared with WTAP (1.01±0.13) and BMI1 (1.02±0.11) expressions in HEB cells, WTAP (2.38±0.17) and BMI1 (2.25±0.14) expressions in U251 cells were increased (P

Metastasis is the main cause of cancer-related death. Growing evidence has shown that changes in glucose metabolism in nasopharyngeal carcinoma cells affect the invasion and metastasis of nasopharyngeal carcinoma through many pathways. This review summarizes the molecular mechanism underlying abnormal glucose metabolism in nasopharyngeal carcinoma cells and analyzes its relationship with the invasion and metastasis of nasopharyngeal carcinoma, including aerobic glycolysis, aerobic oxidation, and pentose phosphate pathway. The aim is to provide novel approaches using the relationships among glucose metabolism, invasion, and metastasis in the targeted therapy of nasopharyngeal carcinoma.

The relationship between tumor metabolism and immunity is complex and diverse. To date, the role of tumor-specific metabolic reprogramming in shaping the specific tumor microenvironment in tumor immunotherapy remains unclear. Lactic acid is the main product of glycolysis, and the aerobic glycolysis of tumor cells causes lactic acid to accumulate in the microenvironment. Recent studies have shown that the accumulation of lactic acid in the tumor microenvironment hinders anti-tumor immunity, especially affects the function, differentiation, and metabolism of immune cells, and participates in tumor immune escape, thus promoting tumor. This article reviews the effects of lactate accumulation in the tumor microenvironment on dendritic cells, T cells, NK cells, tumor-associated macrophages, and myeloid-derived suppressor cells. Targeted intervention of lactate production and efflux by tumor cells is expected to become a new strategy for tumor immunotherapy.

Background: Long noncoding RNAs (lncRNAs) have been reported to play vital roles in the development and progression of cancer. However, their biological significance and functional mechanisms in non-small cell lung cancer (NSCLC) are mostly unclear. Methods: We performed RNA-sequencing to predict the differential expression of lncRNAs in clinical NSCLC and paired paracancerous lung tissues. To identify lncRNA expression, quantitative polymerase chain reaction (qPCR) was used. Using both cell and mouse models, We studied lncRNA AC016727.1's function in NSCLC growth and metastasis. Western blot assays, dual luciferase reporter assays, and chromatin immunoprecipitation were used to analyze the functional mechanism of lncRNA AC016727.1. Results: Our larger NSCLC cohorts validated that the lncRNA AC016727.1 was upregulated in 94 paired NSCLC tissues and correlated with poor survival. Functionally, lncRNA AC016727.1 downregulation inhibited NSCLC cell proliferation, aerobic glycolysis, EMT, and migration, inducing apoptosis. Conversely, upregulated lncRNA AC016727.1 expression exhibited the opposite effect, promoting NSCLC cell survival. Importantly, lncRNA AC016727.1 knockdown inhibited lung cancer growth and slowed the progression of lung metastasis in nude mouse models. Mechanistically, lncRNA AC016727.1 upregulated BACH1 target gene expression by acting as a sponge for miR-98-5p, thereby functioning as a competing endogenous RNA. The function of lncRNA AC016727.1 is mediated by the miR-98-5p/BACH1 axis in NSCLC cells. Meanwhile, the transcription factor HIF-1α can bind to the promoter and activate lncRNA AC016727.1 transcription. lncRNA AC016727.1 regulates HIF-1α expression via BACH1 in NSCLC and forms the lncRNA AC016727.1/BACH1/HIF-1α signaling loop under hypoxic conditions. Conclusion: Our study reveals a novel lncRNA AC016727.1/BACH1/HIF-1α signaling loop in the progression of NSCLC under hypoxic conditions, suggesting that lncRNA AC016727.1 could act as a useful biomarker for NSCLC and a new therapeutic target. [ABSTRACT FROM AUTHOR]

Objective　To investigate Artemisinin-affected cell proliferation and aerobic glycolysis on clear cell renal carcinomas (ccRCC) through regulating ENO2 and clarify the mechanism. Methods　ccRCC cell lines OSRC2 and ACHN were exposed to 0, 10, 20, 30, and 40 µmol/L Artemisinin, OSRC2 and ACHN cells treated with 25 µmol/L Artemisinin or transfected with si-ENO2 at the same time. CCK-8 assay detected cell proliferation, glucose consumption, and lactate production were detected by glucose test kit and lactate test kit. The expressions of HK2, LDHA, and ENO2 were detected by Western blot, and ENO2 mRNA expression was detected by RTqPCR. Results　The survival rate of OSRC2 and ACHN cells were decreased with the increase of Artemisinin concentration and treatment time, the IC50 of OSRC2 cells was 25.47 µmol/L, and the IC50 of ACHN was 26.31 µmol/L. ENO2 was upregulated in OSRC2 and ACHN cells (P < 0.01). and Artemisinin diminished ENO2 expression in cancer cells (all P < 0.05). Exposure to Artemisinin (25 µmol/L) or knocking down ENO2 significantly inhibited the survival of OSRC2 and ACHN cells ( all P < 0.001), glucose consumption ( P < 0.05), lactate production (all P < 0.05) and protein expression of HK2 and LDHA (all P < 0.05). Compared with si-ENO2 group, the survival rate (P < 0.001), glucose consumption (P < 0.05), lactate production (all P < 0.05) and the expression of HK2 and LDHA (all P < 0.05) of OSRC2 and ACHN cells in knocking down ENO2 and treated with 25 µmol/L Artemisinin group were decreased. Conclusion　Artemisinin can inhibit the survival rate and aerobic glycolysis of ccRCC cells, and plays a role by downregulating the expression of ENO2 in ccRCC. [ABSTRACT FROM AUTHOR]

Background: Emerging evidence indicates that circular RNAs (circRNAs) play vital roles in tumor progression, including lung adenocarcinomas (LUAD). However, the mechanisms by which circRNAs promote the progression of LUAD still require further investigation. Methods: Quantitative real-time PCR was performed to detect the expression of circP4HB in LUAD tissues and cells. Then, Kaplan–Meier analysis was used to determine the prognostic value of circP4HB expression. We employed RNA pull-down, RNA immunoprecipitation, mass spectrometry, cells fraction, glucose consumption, lactate production, pyruvate kinase M2 (PKM2) activity, and macrophage polarization assays to uncover the underlying mechanisms of circP4HB in LUAD. Results: We found that circP4HB is upregulated in LUAD tissues and correlated with advanced TNM stages and lymph node metastasis. LUAD patients with high circP4HB expression had poor prognoses. Functionally, circP4HB promoted LUAD progression in vivo and in vitro. Upregulated circP4HB increased glucose consumption, lactate production and accelerated aerobic glycolysis in LUAD cells. Mechanically, circP4HB mainly accumulated in the cytoplasm of LUAD cells and bound with PKM2 and subsequently upregulating PKM2 enzymatic activity by increasing its tetramer formation. Additionally, circP4HB promoted M2 macrophage phenotype shift via targeting PKM2. Finally, rescue assays further confirmed that circP4HB could promote LUAD cell progression through its interaction with PKM2. Conclusion: These results demonstrate that circP4HB could promote LUAD progression, indicating circP4HB might be a potential therapeutic target of LUAD. [ABSTRACT FROM AUTHOR]

Lactate represents the main product of pyruvate reduction catalyzed by the lactic dehydrogenase family of enzymes. Cancer cells utilize great quantities of glucose, shifting toward a glycolytic metabolism. With the contribution of tumor stromal cells and under hypoxic conditions, this leads toward the acidification of the extracellular matrix. The ability to shift between different metabolic pathways is a characteristic of breast cancer cells and is associated with an aggressive phenotype. Furthermore, the preliminary scientific evidence concerning the levels of circulating lactate in breast cancer points toward a correlation between hyperlactacidemia and poor prognosis, even though no clear linkage has been demonstrated. Overall, lactate may represent a promising metabolic target that needs to be investigated in breast cancer. [ABSTRACT FROM AUTHOR]

Modulation of autophagy as an anticancer strategy has been widely studied and evaluated in several cell models. However, little attention has been paid to the metabolic changes that occur in a cancer cell when autophagy is inhibited or induced. In this review, we describe how the expression and regulation of various autophagy-related (ATGs) genes and proteins are associated with cancer progression and cancer plasticity. We present a comprehensive review of how deregulation of ATGs affects cancer cell metabolism, where inhibition of autophagy is mainly reflected in the enhancement of the Warburg effect. The importance of metabolic changes, which largely depend on the cancer type and form part of a cancer cell's escape strategy after autophagy modulation, is emphasized. Consequently, pharmacological strategies based on a dual inhibition of metabolic and autophagy pathways emerged and are reviewed critically here. [ABSTRACT FROM AUTHOR]

Background: Replication factor C subunit 2 (RFC2) participates in the growth and metastasis of various malignancies. Our study investigated the roles of RFC2 in colorectal cancer (CRC). Results: RFC2 expression was upregulated in CRC tissues and cells. High RFC2 expression was associated with poor prognosis. Knockdown RFC2 inhibited proliferation, induced apoptosis, and suppressed migration and invasion of CRC cells. CREB5 was a transcription factor of RFC2, and CREB5 knockdown suppressed RFC2 expression. Furthermore, RFC2 promoted aerobic glycolysis and MET/PI3K/AKT/mTOR pathway. Conclusion: RFC2 promoted the progression of CRC cells via activating aerobic glycolysis and the MET/PI3K/AKT/mTOR pathway. [ABSTRACT FROM AUTHOR]

Background: Despite improvements in prognosis due to advances in treatment, including surgery, genetic screening, and molecular targeted therapy, the outcomes of ovarian cancer (OC) remain unsatisfactory. Internal mRNA modifications are extremely common in eukaryotes; N6-methyladenosine (m6A) alteration has significant effects on mRNA stability and translation, and it is involved in the pathophysiology of numerous diseases related to cancer. Methods: Bioinformatics analysis, quantitative real-time polymerase chain reaction and Western blotting were used to detect the expression of vir-like m6A methyltransferase associated (KIAA1429) in OC tissues and cell lines. Several different cell models and animal models were established to determine the role of KIAA1429 in glucose metabolism reprogramming and the underlying molecular mechanism of OC. The mechanism of oncology functional assays, co-immunoprecipitation and a luciferase reporter gene was employed to ascertain how KIAA1429 interacts with important molecular targets. Results: We reported that KIAA1429 was overexpressed in OC and predicted a poor prognosis. Functionally, KIAA1429 promoted cell growth by inducing proliferation and inhibiting necrosis. Mechanistically, KIAA1429 promoted tumor progression and glycolysis via stabilizing ENO1 mRNA in a way dependent on m6A. Furthermore, we investigated that the SPI1 transcription factor is the main transcription factor that regulates KIAA1429 transcription in OC. Conclusion: Our findings revealed that SPI1/KIAA1429/ENO1 signaling is a novel molecular axis and raises awareness of the vital functions of the changes in KIAA1429 and m6A changes in the metabolic reprogramming of OC. These results identified new potential biomarkers and treatment targets for OC. [ABSTRACT FROM AUTHOR]

The effect of graphene oxide (GO) nanoparticles of 100–200 nm in size coated with linear (LP-GO) and branched (BP-GO) polyethylene glycol at concentrations of 5 and 25 μg/mL on the metabolism of Jurkat tumor cells was studied. It was found that LP-GO nanoparticles at a concentration of 25 μg/mL can enhance basal glycolysis of Jurkat T-lymphocyte tumor cell line cells, while LP-GO and BP-GO at the same concentration can reduce the indicators of compensatory glycolysis. Despite this, GO nanoparticles coated with linear and branched PEG at a concentration of 5 μg/mL do not have pronounced effects on oxidative phosphorylation and glycolysis of Jurkat cells and could therefore be safe for activated T cells. [ABSTRACT FROM AUTHOR]

Aims: The isocitrate dehydrogenase (IDH) phenotype is associated with reprogrammed energy metabolism in glioblastoma (GBM) cells. Small nucleolar RNAs (snoRNAs) are known to exert an important regulatory role in the energy metabolism of tumor cells. The purpose of this study was to investigate the role of C/D box snoRNA U3 and transcription factor zinc finger and BTB domain‐containing 7A (ZBTB7A) in the regulation of aerobic glycolysis and the proliferative capacity of IDH1 wild‐type (IDH1WT) GBM cells. Methods: Quantitative reverse transcription PCR and western blot assays were utilized to detect snoRNA U3 and ZBTB7A expression. U3 promoter methylation status was analyzed via bisulfite sequencing and methylation‐specific PCR. Seahorse XF glycolysis stress assays, lactate production and glucose consumption measurement assays, and cell viability assays were utilized to detect glycolysis and proliferation of IDH1WT GBM cells. Results: We found that hypomethylation of the CpG island in the promoter region of U3 led to the upregulation of U3 expression in IDH1WT GBM cells, and the knockdown of U3 suppressed aerobic glycolysis and the proliferation ability of IDH1WT GBM cells. We found that small nucleolar‐derived RNA (sdRNA) U3‐miR, a small fragment produced by U3, was able to bind to the ZBTB4 3′UTR region and reduce ZBTB7A mRNA stability, thereby downregulating ZBTB7A protein expression. Furthermore, ZBTB7A transcriptionally inhibited the expression of hexokinase 2 (HK2) and lactate dehydrogenase A (LDHA), which are key enzymes of aerobic glycolysis, by directly binding to the HK2 and LDHA promoter regions, thereby forming the U3/ZBTB7A/HK2 LDHA pathway that regulates aerobic glycolysis and proliferation of IDH1WT GBM cells. Conclusion: U3 enhances aerobic glycolysis and proliferation in IDH1WT GBM cells via the U3/ZBTB7A/HK2 LDHA axis. [ABSTRACT FROM AUTHOR]

Myofibroblasts activation intensively contributes to cardiac fibrosis with undefined mechanism. Salvianolic acid A (SAA) is a phenolic component derived from Salvia miltiorrhiza with antifibrotic potency. This study aimed to interrogate the inhibitory effects and underlying mechanism of SAA on myofibroblasts activation and cardiac fibrosis. Antifibrotic effects of SAA were evaluated in mouse myocardial infarction (MI) model and in vitro myofibroblasts activation model. Metabolic regulatory effects and mechanism of SAA were determined using bioenergetic analysis and cross‐validated by multiple metabolic inhibitors and siRNA or plasmid targeting Ldha. Finally, Akt/GSK‐3β‐related upstream regulatory mechanisms were investigated by immunoblot, q‐PCR, and cross‐validated by specific inhibitors. SAA inhibited cardiac fibroblasts‐to‐myofibroblasts transition, suppressed collage matrix proteins expression, and effectively attenuated MI‐induced collagen deposition and cardiac fibrosis. SAA attenuated myofibroblasts activation and cardiac fibrosis by inhibiting LDHA‐driven abnormal aerobic glycolysis. Mechanistically, SAA inhibited Akt/GSK‐3β axis and downregulated HIF‐1α expression by promoting its degradation via a noncanonical route, and therefore restrained HIF‐1α‐triggered Ldha gene expression. SAA is an effective component for treating cardiac fibrosis by diminishing LDHA‐driven glycolysis during myofibroblasts activation. Targeting metabolism of myofibroblasts might occupy a potential therapeutic strategy for cardiac fibrosis. [ABSTRACT FROM AUTHOR]

Background: Age-associated changes in immunity are inextricably linked to chronic inflammation and age-related diseases, the impact of aging on monocyte subsets is poorly understood. Methods: Flow cytometry was applied to distinguish three monocyte subsets between 120 young and 103 aged individuals. We then analyzed the expression profiles of three monocyte subsets from 9 young and 9 older donors and CD14+ monocytes from 1202 individuals between 44 and 83 years old. Flow cytometry was used to measure β-galactosidase activities, ROS levels, mitochondrial contents, mitochondrial membrane potentials (MMPs) and intracellular IL-6 levels in three monocyte subsets of young and elderly individuals, and plasma IL-6 levels were detected by electrochemiluminescence immunoassay. Mitochondrial stress and glycolytic rate of CD14+ monocytes from young and aged individuals were measured by Seahorse XFe24 Analyzer. Results: Compared with young individuals, the percentage of classical subset in aged persons significantly decreased, while the proportion of nonclassical subset increased. Age-related differential genes were obviously enriched in cellular senescence, ROS, oxidative phosphorylation, mitochondrial respiratory chain, IL-6 and ribosome-related pathways. Compared with young individuals, the β-galactosidase activities, ROS contents, intracellular IL-6 levels of three monocyte subsets, and plasma IL-6 levels in aged individuals were significantly elevated, while the MMPs apparently declined with age and the mitochondrial contents were only increased in intermediate and nonclassical subsets. CD14+ monocytes from elderly adults had conspicuously lower basal and spare respiratory capacity and higher basal glycolysis than those from young individuals. Conclusions: During aging, monocytes exhibited senescence-associated secretory phenotype, mitochondrial dysfunction, decreased oxidative phosphorylation and increased glycolysis and the nonclassical subset displayed the clearest features of aging. Our study comprehensively investigated age-related transcriptional alterations of three monocyte subsets and identified the pivotal pathways of monocyte senescence, which may have significant implications for tactics to alleviate age-related conditions. [ABSTRACT FROM AUTHOR]

Cells that undergo normal differentiation mainly rely on mitochondrial oxidative phosphorylation to provide energy, but most tumour cells rely on aerobic glycolysis. This phenomenon is called the "Warburg effect". Phosphoglycerate kinase 1 (PGK1) is a key enzyme in aerobic glycolysis. PGK1 is involved in glucose metabolism as well as a variety of biological activities, including angiogenesis, EMT, mediated autophagy initiation, mitochondrial metabolism, DNA replication and repair, and other processes related to tumorigenesis and development. Recently, an increasing number of studies have proven that PGK1 plays an important role in cancer. In this manuscript, we discussed the effects of the structure, function, molecular mechanisms underlying PGK1 regulation on the initiation and progression of cancer. Additionally, PGK1 is associated with chemotherapy resistance and prognosis in tumour patients. This review presents an overview of the different roles played by PGK1 during tumorigenesis, which will help in the design of experimental studies involving PGK1 and enhance the potential for the use of PGK1 as a therapeutic target in cancer. 52igY7jBAnbBhRvJHFPWGt Video Abstract [ABSTRACT FROM AUTHOR]

In this study, novel methods were developed, which allowed continuous (24/7) measurement of arterial blood pressure and renal blood flow in freely moving rats and the intermittent collection of arterial and renal venous blood to estimate kidney metabolic fluxes of O2 and metabolites. Specifically, the study determined the effects of a high salt (HS; 4.0% NaCl) diet upon whole kidney O2 consumption and arterial and renal venous plasma metabolomic profiles of normal Sprague–Dawley rats. A separate group of rats was studied to determine changes in the cortex and outer medulla tissue metabolomic and mRNAseq profiles before and following the switch from a 0.4% to 4.0% NaCl diet. In addition, targeted mRNA expression analysis of cortical segments was performed. Significant changes in the metabolomic and transcriptomic profiles occurred with feeding of the HS diet. A progressive increase of kidney O2 consumption was found despite a reduction in expression of most of the mRNA encoding enzymes of TCA cycle. A novel finding was the increased expression of glycolysis-related genes in Cx and isolated proximal tubular segments in response to an HS diet, consistent with increased release of pyruvate and lactate from the kidney to the renal venous blood. Data suggests that aerobic glycolysis (eg, Warburg effect) may contribute to energy production under these circumstances. The study provides evidence that kidney metabolism responds to an HS diet enabling enhanced energy production while protecting from oxidative stress and injury. Metabolomic and transcriptomic analysis of kidneys of Sprague-Dawley rats fed a high salt diet. Graphical Abstract [ABSTRACT FROM AUTHOR]

The Warburg effect (or aerobic glycolysis), which was first described in 1926 by Otto Heinrich Warburg, consists of the change in glucose metabolism in cancer cells. In normal cells, glucose metabolism finalizes in the mitochondria through oxidative phosphorylation (OXPHOS) in the presence of oxygen. However, the Warburg effect describes a change in the glucose metabolism in cancer cells, consuming excess glucose and converting it into lactate independently of the presence of oxygen. During this process, a wide variety of enzymes can modify their expression and activity to contribute to the mechanism of deregulated cancer metabolism. Therefore, the modulation of enzymes regulating aerobic glycolysis is a strategy for cancer treatment. Although numerous enzymes play a role in regulating aerobic glycolysis, hexokinase 2 (HK2), pyruvate dehydrogenase kinase (PDK), pyruvate kinase (PK), and lactate dehydrogenase (LDH) are worth mentioning. Numerous modulators of these enzymes have been described in recent years. This review aims to present and group, according to their chemical structure, the most recent emerging molecules targeting the above-mentioned enzymes involved in the Warburg effect in view of the future development of cancer treatments. [ABSTRACT FROM AUTHOR]

Context: Gastric cancer (GC) is a significant contributor to global mortality and is recognized for its elevated prevalence and fatality rates. Nitric Oxide (NO) plays a role in multiple aspects of cancer metastasis and progression. CS-NO is a polysaccharide-based biomaterial with NO-releasing properties that shows promising therapeutic potential. Nonetheless, the action mechanism of CS-NO in GC is still largely unclear. Methods: The present study employed various experimental techniques, including CCK-8 assay, colony formation assay, EdU staining, and transwell assays, to evaluate the proliferation, migration, and invasion of GC cells. Additionally, ELISA was utilized to measure glucose uptake, lactate production, and cellular ATP levels in GC cells. In vivo investigations on nude mice were conducted to validate the in vitro results. Objective: The present study aimed to examine the potential anti-tumor properties of CS-NO on GC through in vitro and in vivo investigations, while also exploring the underlying mechanisms involved. Results: Our data suggested that CS-NO might prevent GC cell invasion and migration. Decreased expressions of GLUT1, HK2, and LDHA further demonstrated that CS-NO significantly suppressed aerobic glycolysis in GC cells. The administration of CS-NO resulted in a significant reduction of YAP and TAZ levels in GC cells. Our data further show that CS-NO treatment could inhibit GC cancer growth in mice, consistent with the significant decrease in Ki67, GLUT1 and YAP expression levels. Discussion and conclusion: These findings could reveal the good effects of CS-NO therapy on inhibiting GC. [ABSTRACT FROM AUTHOR]

Determining the aggressiveness of renal cell carcinoma (RCC) noninvasively is a critical part of the diagnostic workup for treating this disease that kills more than 15,000 people annually in the USA. Recently, we have shown that not only the amount of lactate produced, as a consequence of the Warburg effect, but also its efflux out of the cell, is a critical marker of RCC aggressiveness and differentiating RCCs from benign renal tumors. Enzymatic conversions can now be measured in situ with hyperpolarized (HP) 13 C magnetic resonance (MR) on a sub-minute time scale. Using RCC models, we have shown that this technology can interrogate in real time both lactate production and compartmentalization, which are associated with tumor aggressiveness. The dynamic HP MR data have enabled us to robustly characterize parameters that have been elusive to measure directly in intact living cells and murine tumors thus far. Specifically, we were able to measure the same intracellular lactate longitudinal relaxation time in three RCC cell lines of 16.42 s, and lactate efflux rate ranging from 0.14 to 0.8 s-1 in the least to the most aggressive RCC cell lines and correlate it to monocarboxylate transporter isoform 4 expression. We also analyzed dynamic HP lactate and pyruvate data from orthotopic murine RCC tumors using a simplified one-compartment model, and showed comparable apparent pyruvate to lactate conversion rate (kPL ) values with those measured in vitro. This kinetic modeling was then extended to characterize the lactate dynamics in patient-derived living RCC tissue slices; and even without direct measurement of the extracellular lactate signal the efflux parameter was still assessed and was distinct between the benign renal tumors and RCCs. Across all these preclinical models, the rate parameters of kPL and lactate efflux correlated to cancer aggressiveness, demonstrating the validity of our modeling approach for noninvasive assessment of RCC aggressiveness.

Abstract Ovarian cancer (OC) represents one of the most detrimental gynecological malignancies. RNA‐binding protein eukaryotic translation initiation factor 4A isoform 3 (EIF4A3) is well‐regarded as a definitive oncogene that contributes to the development of multiple malignant tumors. This study sought to elucidate the molecular mechanism of EIF4A3 in OC growth and aerobic glycolysis by regulation of pyruvate dehydrogenase kinase 4 (PDK4) mRNA stability. We determined the EIF4A3 and PDK4 expression levels in OC cell lines and normal ovarian epithelial cells, and subsequently evaluated the cell viability and colony formation by cell counting kit‐8 and colony formation assays. The degree of cell aerobic glycolysis was evaluated by measurements of lactic acid production, glucose intake, adenosine triphosphate level, extracellular oxygen consumption, and protein levels of pyruvate kinase isozymes M2 and hexokinase‐2. Afterwards, we verified the binding of EIF4A3 and PDK4 mRNA via RNA immunoprecipitation, and determined the mRNA stability after actinomycin D treatment. Finally, a series of rescue experiments was performed with pcDNA3.1‐PDK4. EIF4A3 and PDK4 were upregulated in OC cells. Silencing EIF4A3 obstructed cell proliferation and aerobic glycolysis, while the same was annulled by EIF4A3 overexpression. Mechanically, EIF4A3 could bind to PDK4 mRNA to stabilize its mRNA and upregulate its protein levels. PDK4 overexpression inverted the inhibitory role of silencing EIF4A3 in proliferation and aerobic glycolysis. Overall, our findings highlighted that EIF4A3 induced OC progression by stabilizing PDK4 mRNA.

Background: Circular RNAs (circRNAs) have been uncovered to be implicated in the malignant development of bladder cancer (BC). Objective: Herein, this work aimed to investigate the role and mechanism of circRNA ubiquitin-associated protein 2 (circUBAP2) in BC progression. Design, setting, and participants: Quantitative real-time polymerase chain reaction and Western blotting were used for the detection of genes and proteins. Outcome measurements and statistical analysis: In vitro functional experiments were conducted using colony formation, 5-ethynyl-2′-deoxyuridine (EdU), Transwell, wound healing, and flow cytometry assays, respectively. A glycolysis analysis was conducted by assessing glucose uptake and lactate production. A murine xenograft model was established to perform in vivo experiments. The binding interaction between miR-496 and circUBAP2 or DNA topoisomerase 2-alpha (TOP2A) was verified using a dual-luciferase reporter assay. Results and limitations: CircUBAP2 was highly expressed in BC patients, and high circUBAP2 expression showed a shorter survival rate. Functionally, knockdown of circUBAP2 could suppress BC cell growth, migration, invasion, and aerobic glycolysis in vitro, as well as impede BC growth in nude mice. Mechanistically, circUBAP2 acted as a sponge for miR-496, which targeted TOP2A. Moreover, circUBAP2 could indirectly regulate TOP2A expression through sequestering miR-496. Furthermore, a series of rescue experiments showed that miR-496 inhibition reversed the anticancer action of circUBAP2 knockdown on BC cells. Moreover, miR-496 could attenuate BC cell malignant phenotypes and aerobic glycolysis, which were abolished by TOP2A overexpression. Conclusions: Silencing of circUBAP2 could suppress BC growth, invasion, migration, and aerobic glycolysis by the miR-496/TOP2A axis, suggesting a promising target for the molecular targeted therapies of BC. Patient summary: Circular RNA ubiquitin-associated protein 2 (circUBAP2) was found to be associated with poor prognosis in bladder cancer (BC). Knockdown of circUBAP2 might suppress BC growth, invasion, migration, and aerobic glycolysis, indicating that it may be a new target for the development of molecular targeted therapy for BC.

Context: Aerobic glycolysis is a breast cancer hallmark that has become a novel target for anticancer therapy. GLUT1, HK2, PKM2, and LDHA are oncogenic proteins in the pathway. The compounds of ethyl acetate fraction of Selaginella doederleinii Hieron extract can be developed as aerobic glycolysis inhibitors by impeding the proteins’ activity. Aims: To analyze the anticancer activity of compounds of the ethyl acetate fraction of S. doederleinii via inhibiting oncogenic proteins in the aerobic glycolysis pathway. Methods: The 3D protein structures were obtained from the RCSB database. Ligands were compounds of the ethyl acetate fraction predicted to have a good oral bioavailability based on our previous study. The ligand structures were downloaded from the PubChem database. Docking and analysis of chemical interactions were performed using Autodock Vina in Pyrx and Discovery Studio 2020, respectively. Results: Some compounds interacted with the specific binding site of proteins with low binding affinity. Diosgenin interacted with GLUT1 and LDHA with the binding affinity of -11.8 and -9.6 kcal/mol. Frutinone A was found to bind PKM2 and LDHA with the binding affinity of -10.0 and -8.4 kcal/mol. Vitexin interacted with GLUT1 and PKM2 with the binding affinity of -10.4 and -10.0 kcal/mol. Valerodine and 5-hydroxyferulic acid methyl ester could bind HK2 with a binding affinity of -6.1 and -6.8 kcal/mol. Conclusions: The compounds of ethyl acetate fraction of S. doederleinii extract were predicted to inhibit GLUT1, HK2, PKM2, and LDHA. Therefore, these compounds could be developed as anti-breast cancer agents targeting the aerobic glycolysis pathway.

PurposeTo quantify abnormal metabolism of diffuse gliomas using "aerobic glycolytic imaging" and investigate its biological correlation.MethodsAll subjects underwent a pH-weighted amine chemical exchange saturation transfer spin-and-gradient-echo echoplanar imaging (CEST-SAGE-EPI) and dynamic susceptibility contrast perfusion MRI. Relative oxygen extraction fraction (rOEF) was estimated as the ratio of reversible transverse relaxation rate R2' to normalized relative cerebral blood volume. An aerobic glycolytic index (AGI) was derived by the ratio of pH-weighted image contrast (MTRasym at 3.0 ppm) to rOEF. AGI was compared between different tumor types (N = 51, 30 IDH mutant and 21 IDH wild type). Metabolic MR parameters were correlated with 18F-FDG uptake (N = 8, IDH wild-type glioblastoma), expression of key glycolytic proteins using immunohistochemistry (N = 38 samples, 21 from IDH mutant and 17 from IDH wild type), and bioenergetics analysis on purified tumor cells (N = 7, IDH wild-type high grade).ResultsAGI was significantly lower in IDH mutant than wild-type gliomas (0.48 ± 0.48 vs. 0.70 ± 0.48; P = 0.03). AGI was strongly correlated with 18F-FDG uptake both in non-enhancing tumor (Spearman, ρ = 0.81; P = 0.01) and enhancing tumor (ρ = 0.81; P = 0.01). AGI was significantly correlated with glucose transporter 3 (ρ = 0.71; P = 0.004) and hexokinase 2 (ρ = 0.73; P = 0.003) in IDH wild-type glioma, and monocarboxylate transporter 1 (ρ = 0.59; P = 0.009) in IDH mutant glioma. Additionally, a significant correlation was found between AGI derived from bioenergetics analysis and that estimated from MRI (ρ = 0.79; P = 0.04).ConclusionAGI derived from molecular MRI was correlated with glucose uptake (18F-FDG and glucose transporter 3/hexokinase 2) and cellular AGI in IDH wild-type gliomas, whereas AGI in IDH mutant gliomas appeared associated with monocarboxylate transporter density.