The HK2 Dependent "Warburg Effect" and Mitochondrial Oxidative Phosphorylation in Cancer: Targets for Effective Therapy with 3-Bromopyruvate

Tethering of hexokinase 2 to mitochondria promotes resistance of liver cancer cells to natural killer cell cytotoxicity

Hexokinases (HKs) control the first step of glucose catabolism. A switch of expression from liver HK (glucokinase, GCK) to the tumor isoenzyme HK2 is observed in hepatocellular carcinoma progression. Our prior work revealed that HK isoenzyme switch in hepatocytes not only regulates hepatic metabolic functions but also modulates innate immunity and sensitivity to Natural Killer (NK) cell cytotoxicity. This study investigates the impact of HK2 expression and its mitochondrial binding on the resistance of human liver cancer cells to NK-cell-induced cytolysis. We have shown that HK2 expression induces resistance to NK cell cytotoxicity in a process requiring mitochondrial binding of HK2. Neither HK2 nor GCK expression affects target cells' ability to activate NK cells. In contrast, mitochondrial binding of HK2 reduces effector caspase 3/7 activity both at baseline and upon NK-cell activation. Furthermore, HK2 tethering to mitochondria enhances their resistance to cytochrome c release triggered by tBID. These findings indicate that HK2 mitochondrial binding in liver cancer cells is an intrinsic resistance factor to cytolysis and an escape mechanism from immune surveillance.

3-bromopyruvate induces morphological alteration and may initiate programmed cell death in Cryptococcus neoformans cells

3-Bromopyruvate (3BP), known for its potent anticancer properties, also exhibits remarkable efficacy against the pathogenic fungus Cryptococcus neoformans. So far it has been proven that the main fungicidal activity of 3BP is based on ATP depletion and a reduction of intracellular level of glutathione. The presented study includes a broad range of methods to further investigate the mechanistic effects of 3BP on C. neoformans cells. The use of flow cytometry allowed a thorough examination of their survival during 3BP treatment, while observations using electron microscopy made it possible to note the changes in cellular morphology. Utilizing ruthenium red, the study suggests a mitochondrial pathway may initiate programmed cell death in response to 3BP. Analysis of free radical generation and gene expression changes supports this hypothesis. These findings enhance comprehension of 3BP's mechanisms in fungal cells, paving the way for its potential application as a therapeutic agent against cryptococcosis.

Erianin promotes apoptosis and inhibits Akt-mediated aerobic glycolysis of cancer cells

Highly activated aerobic glycolysis provides the metabolic requirements for tumor cell growth and proliferation. Erianin, a natural product isolated from Dendrobium chrysotoxum Lindl, has been reported to exert antitumor activity in multiple cancers. However, whether Erianin exerts inhibitory effects on aerobic glycolysis and the inherent mechanism remain poorly defined in non-small cell lung cancer (NSCLC). Here, we showed that Erianin inhibited the cell viability and proliferation, and induced apoptosis in NSCLC cells. Moreover, Erianin overtly suppressed aerobic glycolysis via decreasing HK2 expression. Mechanistically, Erianin dose-dependently curbed the Akt-GSK3β signaling pathway phosphorylation activation, which afterwards downregulated HK2 expression. Meanwhile, Erianin inhibited HCC827 tumor growth in vivo. Taken together, our results suggest that the natural product Erianin can suppress aerobic glycolysis and exert potent anticancer effects via the Akt-GSK3β signaling pathway in NSCLC cells.

Thyroid cancer cell metabolism: A glance into cell culture system-based metabolomics approaches

Thyroid cancer is the most common malignancy of the endocrine system and the seventh most prevalent cancer in women worldwide. It is a complex and diverse disease characterized by heterogeneity, underscoring the importance of understanding the underlying metabolic alterations within tumor cells. Metabolomics technologies offer a powerful toolset to explore and identify endogenous and exogenous biochemical reaction products, providing crucial insights into the intricate metabolic pathways and processes within living cells. Metabolism plays a central role in cell function, making metabolomics a valuable reflection of a cell's phenotype. In the OMICs era, metabolomics analysis of cells brings numerous advantages over existing methods, propelling cell metabolomics as an emerging field with vast potential for investigating metabolic pathways and their perturbation in pathophysiological conditions. This review article aims to look into recent developments in applying metabolomics for characterizing and interpreting the cellular metabolome in thyroid cancer cell lines, exploring their unique metabolic characteristics. Understanding the metabolic alterations in tumor cells can lead to the identification of critical nodes in the metabolic network that could be targeted for therapeutic intervention.

Role of long non-coding RNAs in metabolic reprogramming of gastrointestinal cancer cells

Metabolic reprogramming, which is recognized as a hallmark of cancer, refers to the phenomenon by which cancer cells change their metabolism to support their increased biosynthetic demands. Tumor cells undergo substantial alterations in metabolic pathways, such as glycolysis, oxidative phosphorylation, pentose phosphate pathway, tricarboxylic acid cycle, fatty acid metabolism, and amino acid metabolism. Latest studies have revealed that long non-coding RNAs (lncRNAs), a group of non-coding RNAs over 200 nucleotides long, mediate metabolic reprogramming in tumor cells by regulating the transcription, translation and post-translational modification of metabolic-related signaling pathways and metabolism-related enzymes through transcriptional, translational, and post-translational modifications of genes. In addition, lncRNAs are closely related to the tumor microenvironment, and they directly or indirectly affect the proliferation and migration of tumor cells, drug resistance and other processes. Here, we review the mechanisms of lncRNA-mediated regulation of glucose, lipid, amino acid metabolism and tumor immunity in gastrointestinal tumors, aiming to provide more information on effective therapeutic targets and drug molecules for gastrointestinal tumors.

Association between glycolysis markers and prognosis of liver cancer: a systematic review and meta-analysis

BACKGROUND

In recent years, the capacity of tumor cells to maintain high levels of glycolysis, even in the presence of oxygen, has emerged as one of the main metabolic traits and garnered considerable attention. The purpose of this meta-analysis is to investigate the prognostic value of glycolysis markers in liver cancer.

METHODS

PubMed, Embase, and Cochrane Library databases were searched for articles on glycolytic marker expression levels associated with the prognosis of liver cancer until April 2023. Stata SE14.0 was used to calculate the aggregate hazard ratios and 95% confidence intervals.

RESULTS

Thirty-five studies were included. The worse overall survival (OS) (P < 0.001), disease-free survival (DFS) (P = 0.001), recurrence-free survival (RFS) (P = 0.004), and time to recurrence (TTR) (P < 0.001) were significantly associated with elevated expression of glycolysis markers. Higher expression of PKM2 (P < 0.001), STMN1 (P = 0.002), MCT4 (P < 0.001), GLUT1 (P = 0.025), HK-2 (P < 0.001), and CA9 (P < 0.001) were significantly related to shorter OS. Increased levels of PKM2 (P < 0.001), CA9 (P = 0.005), and MCT4 (P < 0.001) were associated with worse DFS. Elevated PKM2 expression (P = 0.002) was also associated with poorer RFS in hepatocellular carcinoma patients. GLUT2 expression was not correlated with the prognosis of liver cancer (P = 0.134).

CONCLUSIONS

Elevated expression of glycolysis markers was associated with worse OS, DFS, RFS, and TTR in patients with liver cancer. Therefore, these glycolysis markers could serve as potential prognostic markers and therapeutic targets in liver cancer.

TRIAL REGISTRATION

PROSPERO registration: CRD42023469645.

The Aurora kinase inhibitor AT9283 inhibits Burkitt lymphoma growth by regulating Warburg effect

Objective

To investigate the effect of the kinase inhibitor AT9283 on Burkitt lymphoma (BL) cells and elucidate the underlying mechanisms.

Methods

The effect of AT9283 on the proliferation of BL cell lines was tested using the MTT assay. Apoptosis and cell cycle were measured by flow cytometry. The proteins associated with the cell cycle, apoptosis, and the Warburg effect were detected using Western blotting. Alterations in glycolytic metabolism in terms of glucose intake and lactate concentrations were determined by glucose and lactate assays.

Results

The current study utilized the GEPIA, the Human Protein Atlas (HAP) database and immunohistochemistry to conduct analyses, which revealed a high expression of Aurora kinases and Warburg effect-related proteins in malignant B-cell lymphoma tissues. AT9283 significantly inhibited the cell proliferation of BL cells and induced G2/M arrest. Additionally, AT9283 induced apoptosis in BL cells and reversed the Warburg effect by increasing glucose uptake and reducing lactate production. Moreover, the protein expression of hexokinase 2, pyruvate kinase M2, and lactate dehydrogenase A was significantly suppressed by AT9283, possibly through the inhibition of c-Myc and HIF-1α protein expression.

Conclusion

The reversal of the Warburg effect in BL cells and the subsequent inhibition of cell proliferation and induction of apoptosis were observed by targeting Aurora A and Aurora B with AT9283. This finding may present new therapeutic options and targets for BL.

The potential role of reprogrammed glucose metabolism: an emerging actionable codependent target in thyroid cancer

Although the incidence of thyroid cancer is increasing year by year, most patients, especially those with differentiated thyroid cancer, can usually be cured with surgery, radioactive iodine, and thyroid-stimulating hormone suppression. However, treatment options for patients with poorly differentiated thyroid cancers or radioiodine-refractory thyroid cancer have historically been limited. Altered energy metabolism is one of the hallmarks of cancer and a well-documented feature in thyroid cancer. In a hypoxic environment with extreme nutrient deficiencies resulting from uncontrolled growth, thyroid cancer cells utilize "metabolic reprogramming" to satisfy their energy demand and support malignant behaviors such as metastasis. This review summarizes past and recent advances in our understanding of the reprogramming of glucose metabolism in thyroid cancer cells, which we expect will yield new therapeutic approaches for patients with special pathological types of thyroid cancer by targeting reprogrammed glucose metabolism.

Histone Methyltransferase NSD2 Activates PKCα to Drive Metabolic Reprogramming and Lenalidomide Resistance in Multiple Myeloma

Multiple myeloma cells undergo metabolic reprogramming in response to the hypoxic and nutrient-deprived bone marrow microenvironment. Primary oncogenes in recurrent translocations might be able to drive metabolic heterogeneity to survive the microenvironment that can present new vulnerabilities for therapeutic targeting. t(4;14) translocation leads to the universal overexpression of histone methyltransferase NSD2 that promotes plasma cell transformation through a global increase in H3K36me2. Here, we identified PKCα as an epigenetic target that contributes to the oncogenic potential of NSD2. RNA sequencing of t(4;14) multiple myeloma cell lines revealed a significant enrichment in the regulation of metabolic processes by PKCα, and the glycolytic gene, hexokinase 2 (HK2), was transcriptionally regulated by PKCα in a PI3K/Akt-dependent manner. Loss of PKCα displaced mitochondria-bound HK2 and reversed sensitivity to the glycolytic inhibitor 3-bromopyruvate. In addition, the perturbation of glycolytic flux led to a metabolic shift to a less energetic state and decreased ATP production. Metabolomics analysis indicated lactate as a differential metabolite associated with PKCα. As a result, PKCα conferred resistance to the immunomodulatory drugs (IMiD) lenalidomide in a cereblon-independent manner and could be phenocopied by either overexpression of HK2 or direct supplementation of lactate. Clinically, t(4;14) patients had elevated plasma lactate levels and did not benefit from lenalidomide-based regimens. Altogether, this study provides insights into the epigenetic-metabolism cross-talk in multiple myeloma and highlights the opportunity for therapeutic intervention that leverages the distinct metabolic program in t(4;14) myeloma.

SIGNIFICANCE

Aberrant glycolysis driven by NSD2-mediated upregulation of PKCα can be therapeutically exploited using metabolic inhibitors with lactate as a biomarker to identify high-risk patients who exhibit poor response towards IMiD-based regimens.

Gastrodin overcomes chemoresistance via inhibiting Skp2-mediated glycolysis

Aerobic glycolysis, a typical phenotype in human tumors, is associated with tumor progression and chemotherapy resistance. The present study demonstrated that cisplatin-resistant oral squamous cell carcinoma (OSCC) cells exerted a stronger glycolysis ability, which was associated with hexokinase 2 (HK2) overexpression. Additionally, the tumor growth of OSCC cells was delayed in vivo and the glycolysis was notably decreased following HK2 knockdown. The natural compound screening revealed that gastrodin could be an effective candidate for OSCC therapy since it inhibited HK2-mediated glucose metabolism and promoted endogenous OSCC cell apoptosis. Furthermore, gastrodin could bind to protein kinase B (Akt) and suppress its activity, thus downregulating HK2 at the transcriptional level. Additionally, S-phase kinase-associated protein 2 (Skp2) was highly expressed in OSCC cells, while K63-linked ubiquitination of Akt was inhibited in Skp2-depleted cisplatin-resistant OSCC cells. Gastrodin could also inhibit the cisplatin resistance of OSCC cells in vivo, particularly when combined with the Skp2 inhibitor, SZL P1-41. Overall, the aforementioned finding suggested that targeting the Skp2-Akt axis could be a potential therapeutic strategy for treating OSCC and overcoming chemoresistance.

Natural epidithiodiketopiperazine alkaloids as potential anticancer agents: Recent mechanisms of action, structural modification, and synthetic strategies

Cancer has become a grave health crisis that threatens the lives of millions of people worldwide. Because of the drawbacks of the available anticancer drugs, the development of novel and efficient anticancer agents should be encouraged. Epidithiodiketopiperazine (ETP) alkaloids with a 2,5-diketopiperazine (DKP) ring equipped with transannular disulfide or polysulfide bridges or S-methyl moieties constitute a special subclass of fungal natural products. Owing to their privileged sulfur units and intriguing architectural structures, ETP alkaloids exhibit excellent anticancer activities by regulating multiple cancer proteins/signaling pathways, including HIF-1, NF-κB, NOTCH, Wnt, and PI3K/AKT/mTOR, or by inducing cell-cycle arrest, apoptosis, and autophagy. Furthermore, a series of ETP alkaloid derivatives obtained via structural modification showed more potent anticancer activity than natural ETP alkaloids. To solve supply difficulties from natural resources, the total synthetic routes for several ETP alkaloids have been designed. In this review, we summarized several ETP alkaloids with anticancer properties with particular emphasis on their underlying mechanisms of action, structural modifications, and synthetic strategies, which will offer guidance to design and innovate potential anticancer drugs.

Sulconazole induces PANoptosis by triggering oxidative stress and inhibiting glycolysis to increase radiosensitivity in esophageal cancer

Esophageal cancer is the seventh most common cancer in the world. Although traditional treatment methods such as radiotherapy and chemotherapy have good effects, their side effects and drug resistance remain problematic. The repositioning of drug function provides new ideas for the research and development of anticancer drugs. We previously showed that the Food and Drug Administration (FDA)-approved drug sulconazole can effectively inhibit the growth of esophageal cancer cells, but its molecular mechanism is not clear. Here, our study demonstrated that sulconazole had a broad spectrum of anticancer effects. It can not only inhibit the proliferation, but also inhibit the migration of esophageal cancer cells. Both transcriptomic sequencing and proteomic sequencing showed that sulconazole could promote various types of programmed cell death and inhibit glycolysis and its related pathways. Experimentally, we found that sulconazole induced apoptosis, pyroptosis, necroptosis and ferroptosis. Mechanistically, sulconazole triggered mitochondrial oxidative stress and inhibited glycolysis. Finally, we showed that low-dose sulconazole can increase radiosensitivity of esophageal cancer cells. Taken together, these new findings provide strong laboratory evidence for the clinical application of sulconazole in esophageal cancer.

Sestrin2-mediated disassembly of stress granules dampens aerobic glycolysis to overcome glucose starvation

Sestrins are a small gene family of pleiotropic factors whose actions promote cell adaptation to a range of stress conditions. In this report we disclose the selective role of Sestrin2 (SESN2) in dampening aerobic glycolysis to adapt to limiting glucose conditions. Removal of glucose from hepatocellular carcinoma (HCC) cells inhibits glycolysis associated with the downregulation of the rate-limiting glycolytic enzyme hexokinase 2 (HK2). Moreover, the accompanying upregulation of SESN2 through an NRF2/ATF4-dependent mechanism plays a direct role in HK2 regulation by destabilizing HK2 mRNA. We show SESN2 competes with insulin like growth factor 2 mRNA binding protein 3 (IGF2BP3) for binding with the 3'-UTR region of HK2 mRNA. Interactions between IGF2BP3 and HK2 mRNA result in their coalescence into stress granules via liquid-liquid phase separation (LLPS), a process which serves to stabilize HK2 mRNA. Conversely, the enhanced expression and cytoplasmic localization of SESN2 under glucose deprivation conditions favors the downregulation of HK2 levels via decreases in the half-life of HK2 mRNA. The resulting dampening of glucose uptake and glycolytic flux inhibits cell proliferation and protect cells from glucose starvation-induced apoptotic cell death. Collectively, our findings reveal an intrinsic survival mechanism allowing cancer cells to overcome chronic glucose shortages, also providing new mechanistic insights into SESN2 as an RNA-binding protein with a role in reprogramming of cancer cell metabolism.

Let-7b-5p inhibits breast cancer cell growth and metastasis via repression of hexokinase 2-mediated aerobic glycolysis

Hexokinase 2 (HK2), a critical rate-limiting enzyme in the glycolytic pathway catalyzing hexose phosphorylation, is overexpressed in multiple human cancers and associated with poor clinicopathological features. Drugs targeting aerobic glycolysis regulators, including HK2, are in development. However, the physiological significance of HK2 inhibitors and mechanisms of HK2 inhibition in cancer cells remain largely unclear. Herein, we show that microRNA-let-7b-5p (let-7b-5p) represses HK2 expression by targeting its 3'-untranslated region. By suppressing HK2-mediated aerobic glycolysis, let-7b-5p restrains breast tumor growth and metastasis both in vitro and in vivo. In patients with breast cancer, let-7b-5p expression is significantly downregulated and is negatively correlated with HK2 expression. Our findings indicate that the let-7b-5p/HK2 axis plays a key role in aerobic glycolysis as well as breast tumor proliferation and metastasis, and targeting this axis is a potential therapeutic strategy for breast cancer.

C-Terminal Truncated HBx Facilitates Oncogenesis by Modulating Cell Cycle and Glucose Metabolism in FXR-Deficient Hepatocellular Carcinoma

Farnesoid X receptor (FXR) is a nuclear receptor known to play protective roles in anti-hepatocarcinogenesis and regulation of the basal metabolism of glucose, lipids, and bile acids. FXR expression is low or absent in HBV-associated hepatocarcinogenesis. Full-length HBx and HBx C-terminal truncation are frequently found in clinical HCC samples and play distinct roles in hepatocarcinogenesis by interacting with FXR or FXR signaling. However, the impact of C-terminal truncated HBx on the progression of hepatocarcinogenesis in the absence of FXR is unclear. In this study, we found that one known FXR binding protein, a C-terminal truncated X protein (HBx C40) enhanced obviously and promoted tumor cell proliferation and migration by altering cell cycle distribution and inducing apoptosis in the absence of FXR. HBx C40 enhanced the growth of FXR-deficient tumors in vivo. In addition, RNA-sequencing analysis showed that HBx C40 overexpression could affect energy metabolism. Overexpressed HSPB8 aggravated the metabolic reprogramming induced by down-regulating glucose metabolism-associated hexokinase 2 genes in HBx C40-induced hepatocarcinogenesis. Overall, our study suggests that C-terminal truncated HBx C40 synergizes with FXR deficiency by altering cell cycle distribution as well as disturbing glucose metabolism to promote HCC development.

Identification of key genes in hepatocellular carcinoma associated with exposure to TCDD and α-endosulfan by WGCNA

2,3,7,8-tet-rachlorodibenzo-p-dioxin (TCDD) and α-endosulfan are two typical persistent organic pollutants (POPs), both of which accumulate in the liver and have potential carcinogenic hepatic effects. The underlying molecular mechanisms of pathogenesis of hepatocellular carcinoma (HCC) remain elusive when exposure to POPs. The aim of this study is to explore the key genes involved in HCC when exposure to TCDD and α-endosulfan by weighted gene co-expression network analysis (WGCNA). First, we performed co-expressed analysis on HCC and normal condition, based on WGCNA. In results, seven co-expressed modules were identified from 56 human liver samples, and the brown module correlated with five stages of HCC. Subsequently, we predicted that human five liver diseases were associated with exposure to TCDD and/or α-endosulfan by Nextbio analysis. Functional enrichment analysis showed that the brown module enriched in oxidation-reduction process, DNA replication, oxidoreductase activity and aging, which were the same as the results when exposure to the mixture of TCDD and α-endosulfan. Lastly, based on the protein-protein interaction network, we identified three novel genes including HK2, EXO1 and PFKP as key genes in HCC associated with exposure to TCDD and α-endosulfan mixture. In addition, survival analysis of key genes in Kaplan-Meier plotter demonstrated that aberrant expression levels of all the three key genes were associated with poor prognosis of HCC. Finally, Western blot analysis confirmed that protein expression levels of PFKP and HK2 in the three exposed groups were significantly elevated, while EXO1 were significantly upregulated when exposure to TCDD and α-endosulfan mixture in HepaRG cells. This study provides a new perspective to the understanding of the genetic mechanism of HCC when exposure to POPs.

Genetic mutations affecting mitochondrial function in cancer drug resistance

Mitochondria are organelles that serve as a central hub for physiological processes in eukaryotes, including production of ATP, regulation of calcium dependent signaling, generation of ROS, and regulation of apoptosis. Cancer cells undergo metabolic reprogramming in an effort to support their increasing requirements for cell survival, growth, and proliferation, and mitochondria have primary roles in these processes. Because of their central function in survival of cancer cells and drug resistance, mitochondria are an important target in cancer therapy and many drugs targeting mitochondria that target the TCA cycle, apoptosis, metabolic pathway, and generation of ROS have been developed. Continued use of mitochondrial-targeting drugs can lead to resistance due to development of new somatic mutations. Use of drugs is limited due to these mutations, which have been detected in mitochondrial proteins. In this review, we will focus on genetic mutations in mitochondrial target proteins and their function in induction of drug-resistance.

Identification and Validation of the Anoikis-Related Gene Signature as a Novel Prognostic Model for Cervical Squamous Cell Carcinoma, Endocervical Adenocarcinoma, and Revelation Immune Infiltration

Background and Objectives: Cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) are malignant disorders with adverse prognoses for advanced patients. Anoikis, which is involved in tumor metastasis, facilitates the survival and separation of tumor cells from their initial site. Unfortunately, it is rarely studied, and in the literature, studies have only addressed the prognosis character of anoikis for patients with CESC. Materials and Methods: We utilized anoikis-related genes (ANRGs) to construct a prognostic signature in CESC patients that were selected from the Genecards and Harmonizome portals. Furthermore, we revealed the underlying clinical value of this signature for clinical maneuvers by providing clinical specialists with an innovative nomogram on the basis of ANRGs. Finally, we investigated the immune microenvironment and drug sensitivity in different risk groups. Results: We screened six genes from fifty-eight anoikis-related differentially expressed genes in the TCGA-CESC cohort, and we constructed a prognostic signature. Then, we built a nomogram combined with CESC clinicopathological traits and risk scores, which demonstrated that this model may improve the prognosis of CESC patients in clinical therapy. Next, the prognostic risk scores were confirmed to be an independent prognostic indicator. Additionally, we programmed a series of analyses, which included immune infiltration analysis, therapy-related analysis, and GSVA enrichment analysis, to identify the functions and mechanisms of the prognostic models during the progression of cancer in CESC patients. Finally, we performed quantitative reverse transcription polymerase chain reaction (qRT-PCR) to verify the six ANRGs. Conclusions: The present discovery verified that the predictive 6-anoikis-related gene (6-ANRG) signature and nomogram serve as imperative factors that might notably impact a CESC patient's prognosis, and they may be able to provide new clinical evidence to assume the role of underlying biological biomarkers and thus become indispensable indicators for prospective diagnoses and advancing therapy.

3-Bromopyruvate-Loaded Ti3C2 MXene/Cu2O Nanosheets for Photoacoustic Imaging-Guided and Hypoxia-Relieving Enhanced Photothermal/Chemodynamic Therapy

Chemodynamic therapy (CDT) is an innovative and effective treatment that relies on the Fenton or Fenton-like reaction, in which endogenous H₂O₂ overproduction is converted into cytotoxic hydroxyl radicals (^•OH) to suppress tumor growth. Nevertheless, the therapeutic efficiency of CDT is severely restricted by undesirable properties, such as reaction conditions and catalyst performance. Herein, a 2D Ti₃C₂ MXene/Cu₂O nanosheet (MCP NS)-based multifunctional nanoplatform (3-BP@MCG NSs) has been constructed, in which glucose oxidase (GOx) and respiration inhibitor 3-bromopyruvate (3-BP) are sequentially embedded. In this structure, the copper-based catalyst Cu₂O releases Cu⁺ in an acid-triggered manner in the tumor microenvironment (TME), which activates the Fenton-like reaction to catalyze the generation of ^•OH for CDT. The composite has excellent photothermal properties and a high-resolution photoacoustic imaging (PAI) capability in the near-infrared (NIR) region, and especially under NIR irradiation, the photothermal effect generated by the nanosheets accelerates catalysis. GOx is a natural enzyme catalyst for depleting glucose and oxygen content in cells, upregulating H₂O₂ levels in situ, and thereby improving the therapeutic effect of CDT. What is more, the supported 3-BP not only reduces oxygen consumption to alleviate hypoxia levels but also inhibits the glycolysis process and lowers ATP levels by suppressing hexokinase activity. As a result, 3-BP@MCG NSs optimize the unique properties of MCP NSs, GOx, and 3-BP via mutual promotion, realizing self-enhanced PTT/CDT synergistic therapy. This work establishes an emerging strategy for highly efficient PAI-guided integrated treatment and provides a proof of concept for the cooperation of hypoxia relief and in situ H₂O₂ and NIR synergistic enhancement to improve therapeutic efficiency.

Triptolide inhibits intrahepatic cholangiocarcinoma growth by suppressing glycolysis via the AKT/mTOR pathway

BACKGROUND

High levels of glycolysis supply large quantities of energy and biological macromolecular raw materials for cell proliferation. Triptolide (TP) is a kind of epoxy diterpene lactone extracted from the roots, flowers, leaves, or grains of the Celastraceae plant, Tripterygium wilfordii. TP has multiple biological activities, including anti-inflammatory, immunologic suppression, and anti-cancer effects. Nevertheless, it is little known regarding its anti-intrahepatic cholangiocarcinoma (ICC) growth, and the mechanism still require exploration.

PURPOSE

This research explored the effect of TP on ICC growth and investigated whether TP inhibits glycolysis via the AKT/mTOR pathway.

METHODS

Cell proliferation was analyzed by Cell Counting Kit-8 (CCK-8), clonogenic assay, and flow cytometry. The underlying molecular mechanism was identified by determining glucose consumption, ATP production, lactate production, hexokinase (HK) and pyruvate kinase (PK) activity, and Western blot analysis. A rapid ICC model of AKT/YapS127A oncogene coactivation in mice was used to clarify the effect of TP treatment on tumor growth and glycolysis.

RESULTS

The results showed that TP treatment significantly inhibited ICC cell proliferation and glycolysis in a dose- and time-dependent manner(P < 0.05). Further analysis suggested that TP suppressed ICC cell glycolysis by targeting AKT/mTOR signaling. Additionally, we found that TP inhibits tumor growth and glycolysis in AKT/YapS127A mice(P < 0.05).

CONCLUSION

Taken together, we revealed that TP suppressed ICC growth by suppressing glycolysis via the AKT/mTOR pathway and may provide a potential therapeutic target for ICC treatment.

Targeting glycolysis for cancer therapy using drug delivery systems

There is close crosstalk between cancer metabolism and immunity. Cancer metabolism regulation is a promising therapeutic target for cancer immunotherapy. Warburg effect is characterized by abnormal glucose metabolism that includes common features of increased glucose uptake and lactate production. The aerobic glycolysis can reprogram the cancer cells and promote the formation of a suppressive immune microenvironment. As a case in point, lactate plays an essential role in tumorigenesis, which is the end product of glycolysis as well as serves as a fuel supporting cancer cell survival. Meanwhile, it is also an important immune regulator that drives immunosuppression in tumors. Immunometabolic therapy is to intervene tumor metabolism and regulate the related metabolites that participate in the innate and acquired immunity, thereby reinstalling the immune balance and eliciting anticancer immune responses. In this contribution to the Orations - New Horizons of the Journal of controlled Release I will provide an overview of glucose metabolism in tumors and its effects on drug resistance and tumor metastasis, and present the advance of glycolysis-targeting therapy strategies with drug delivery techniques, as well as discuss the challenges in glycolysis-targeting immunometabolic therapy.

Identification of plant-based hexokinase 2 inhibitors: combined molecular docking and dynamics simulation studies

Cancer cells ferment glucose, even under aerobic conditions, following a phenomenon known as the 'Warburg effect.' Hexokinase 2 (HK2) catalyzes the crucial step of phosphorylation of glucose for subsequent utilization in glycolysis and other pathways. HK2 has been proposed as a potential therapeutic target for anti-cancer therapy because of its enhanced expression in glucose-dependent tumors. Here, we have employed structure-based virtual screening using in-house library to identify potential phytoconstituents which could inhibit the HK2 activity. The initial hits were selected based on their binding affinity towards HK2 using the molecular docking approach. Subsequently, the filters for physicochemical properties, PAINS patterns and PASS evaluation were applied to find potential hits against HK2. Finally, we have identified epigallocatechin gallate (EGCG) and quercitrin, two natural compounds with appreciable binding affinity, efficiency and specificity towards the HK2 binding pocket. Both compounds were found to be binding preferentially to the HK2 active site and showed a decent set of drug-like properties. All-atom molecular dynamics (MD) simulations for 100 ns were carried out to see the conformational dynamics, complexes stability and interaction mechanism of HK2 with EGCG and quercitrin. MD simulation results showed that HK2 forms stable protein-ligand complexes with EGCG and quercitrin with consistency throughout the trajectory. Overall, these findings suggest that EGCG and quercitrin might be further exploited as promising scaffolds in the drug development process against HK2..Communicated by Ramaswamy H. Sarma.

Design of Nanoparticles in Cancer Therapy Based on Tumor Microenvironment Properties

Cancer is one of the leading causes of death worldwide, and battling cancer has always been a challenging subject in medical sciences. All over the world, scientists from different fields of study try to gain a deeper knowledge about the biology and roots of cancer and, consequently, provide better strategies to fight against it. During the past few decades, nanoparticles (NPs) have attracted much attention for the delivery of therapeutic and diagnostic agents with high efficiency and reduced side effects in cancer treatment. Targeted and stimuli-sensitive nanoparticles have been widely studied for cancer therapy in recent years, and many more studies are ongoing. This review aims to provide a broad view of different nanoparticle systems with characteristics that allow them to target diverse properties of the tumor microenvironment (TME) from nanoparticles that can be activated and release their cargo due to the specific characteristics of the TME (such as low pH, redox, and hypoxia) to nanoparticles that can target different cellular and molecular targets of the present cell and molecules in the TME.

Targeted Mitochondrial Drugs for Treatment of Ischemia-Reperfusion Injury

Ischemia-reperfusion injury is a complex hemodynamic pathology that is a leading cause of death worldwide and occurs in many body organs. Numerous studies have shown that mitochondria play an important role in the occurrence mechanism of ischemia-reperfusion injury and that mitochondrial structural abnormalities and dysfunction lead to the disruption of the homeostasis of the whole mitochondria. At this time, mitochondria are not just sub-organelles to produce ATP but also important targets for regulating ischemia-reperfusion injury; therefore, drugs targeting mitochondria can serve as a new strategy to treat ischemia-reperfusion injury. Based on this view, in this review, we discuss potential therapeutic agents for both mitochondrial structural abnormalities and mitochondrial dysfunction, highlighting the application and prospects of targeted mitochondrial drugs in the treatment of ischemia-reperfusion injury, and try to provide new ideas for the clinical treatment of the ischemia-reperfusion injury.

UBR7 inhibits HCC tumorigenesis by targeting Keap1/Nrf2/Bach1/HK2 and glycolysis

BACKGROUND

Glycolysis metabolism is an attractive target for cancer therapy. Reprogramming metabolic pathways could improve the ability of metabolic inhibitors to suppress cancers with limited treatment options. The ubiquitin-proteasome system facilitates the turnover of most intracellular proteins with E3 ligase conferring the target selection and specificity. Ubiquitin protein ligase E3 component N-recognin 7 (UBR7), among the least studied E3 ligases, recognizes its substrate through a plant homeodomain (PHD) finger. Here, we bring into focus on its suppressive role in glycolysis and HCC tumorigenesis, dependent on its E3 ubiquitin ligase activity toward monoubiquitination of histone H2B at lysine 120 (H2BK120ub).

METHODS

In this study, we carried out high-throughput RNAi screening to identify epigenetic candidates in regulating lactic acid and investigated its possible roles in HCC progression.

RESULTS

UBR7 loss promotes HCC tumorigenesis both in vitro and in vivo. UBR7 inhibits glycolysis by indirectly suppressing HK2 expression, a downstream target of Nrf2/Bach1 axis. Mechanically, UBR7 regulates H2BK120ub to bind to Keap1 promoter through H2BK120ub monoubiquitination, thereby modulating Keap1 expression and downstream Nrf2/Bach1/HK2 signaling. Pharmaceutical and genetic inhibition of glycolytic enzymes attenuate the promoting effect of UBR7 deficiency on tumor growth. In addition, methyltransferase ALKBH5, downregulated in HCC, regulated UBR7 expression in an m6A-dependent manner.

CONCLUSIONS

These results collectively establish UBR7 as a critical negative regulator of aerobic glycolysis and HCC tumorigenesis through regulation of the Keap1/Nrf2/Bach1/HK2 axis, providing a potential clinical and therapeutic target for the HCC treatment.

Cordycepin Inhibits the Growth of Hepatocellular Carcinoma by Regulating the Pathway of Aerobic Glycolysis

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in China, with a high incidence and mortality rate. Glucose metabolism reprogramming is a major characteristic of tumor cells. Increasing evidence indicates that aerobic glycolysis is associated with tumor growth and insensitivity to chemotherapy. Cordycepin inhibits the growth of HCC cells, but the mechanism is yet to be elucidated. Herein, in vitro and in vivo methods were utilized to investigate the cordycepin-inhibited growth of HCC by regulating the metabolic pathway of aerobic glycolysis. In vitro analyses using colony formation and flow cytometry revealed that cordycepin inhibits HCC cells’ proliferation and promotes apoptosis. In addition, cordycepin reduced the production of lactic acid and pyruvate, reduced the uptake of glucose, and decreased the extracellular acidification in HCC cells. Specifically, cordycepin inhibited the expression of HK2, LDHA, and PKM2 in aerobic glycolysis via the AMPK-Akt pathway. Taken together, these findings revealed that cordycepin reduces the tumor energy supply and decreases lactic acid production, thereby inhibiting the growth of HCC cells by regulating the metabolic pathway of aerobic glycolysis. These findings might provide novel insights into the mechanisms underlying cordycepin-mediated inhibition of tumor growth as well as a new treatment for HCC.

Aerobic glycolysis enhances HBx-initiated hepatocellular carcinogenesis via NF-κBp65/HK2 signalling

BACKGROUND

Aerobic glycolysis has been recognized as one of the growth-promoting metabolic alterations of cancer cells. Emerging evidence indicates that nuclear factor κB (NF-κB) plays significant roles in metabolic adaptation in normal cells and cancer cells. However, whether and how NF-κB regulates metabolic reprogramming in hepatocellular carcinoma (HCC), specifically hepatitis B virus X protein (HBx)-initiated HCC, has not been determined.

METHODS

A dataset of the HCC cohort from the TCGA database was used to analyse the expression of NF-κB family members. Expression of NF-κBp65 and phosphorylation of NF-κBp65 (p-p65) were detected in liver tissues from HBV-related HCC patients and normal controls. A newly established HBx^+/+/NF-κBp65^f/f and HBx^+/+/NF-κBp65^Δhepa spontaneous HCC mouse model was used to investigate the effects of NF-κBp65 on HBx-initiated hepatocarcinogenesis. Whether and how NF-κBp65 is involved in aerobic glycolysis induced by HBx in hepatocellular carcinogenesis were analysed in vitro and in vivo.

RESULTS

NF-κBp65 was upregulated in HBV-related HCC, and HBx induced NF-κBp65 upregulation and phosphorylation in vivo and in vitro. Hepatocyte-specific NF-κBp65 deficiency remarkably decreased HBx-initiated spontaneous HCC incidence in HBx-TG mice. Mechanistically, HBx induced aerobic glycolysis by activating NF-κBp65/hexokinase 2 (HK2) signalling in spontaneous hepatocarcinogenesis, and overproduced lactate significantly promoted HCC cell pernicious proliferation via the PI3K (phosphatidylinositide 3-kinase)/Akt pathway in hepatocarcinogenesis.

CONCLUSION

The data elucidate that NF-κBp65 plays a pivotal role in HBx-initiated spontaneous HCC, which depends on hyperactive NF-κBp65/HK2-mediated aerobic glycolysis to activate PI3K/Akt signalling. Thus, phosphorylation of NF-κBp65 will be a potential therapeutic target for HBV-related HCC.

A pan-cancer analysis of the role of hexokinase II (HK2) in human tumors

More and more evidence show that HK2 is closely related to tumors. But no pan-cancer analysis is available. This paper aimed to explore the potential roles of HK2 across thirty-three tumors based on the datasets of the cancer genome Atlas (TCGA) and gene expression omnibus. HK2 is highly expressed in most tumors and related to the progression of some tumors. HK2 expression was associated with the infiltration of T follicular helper cells for the TCGA tumors of uveal melanoma, breast invasive carcinoma (BRCA), breast invasive carcinoma-luminalA (BRCA-LumA), head and neck squamous cell carcinoma (HNSC), head and neck squamous cell carcinoma with HPV positive (HNSC-HPV⁺), and cancer-associated fibroblasts for the tumors of brain lower grade glioma and stomach adenocarcinoma. Our first pan-cancer study offers a relatively comprehensive understanding of the roles of HK2 in different tumors.

The RNA m6A writer WTAP in diseases: structure, roles, and mechanisms

N6-methyladenosine (m⁶A) is a widely investigated RNA modification in studies on the "epigenetic regulation" of mRNAs that is ubiquitously present in eukaryotes. Abnormal changes in m⁶A levels are closely related to the regulation of RNA metabolism, heat shock stress, tumor occurrence, and development. m⁶A modifications are catalyzed by the m⁶A writer complex, which contains RNA methyltransferase-like 3 (METTL3), methyltransferase-like 14 (METTL14), Wilms tumor 1-associated protein (WTAP), and other proteins with methyltransferase (MTase) capability, such as RNA-binding motif protein 15 (RBM15), KIAA1429 and zinc finger CCCH-type containing 13 (ZC3H13). Although METTL3 is the main catalytic subunit, WTAP is a regulatory subunit whose function is to recruit the m⁶A methyltransferase complex to the target mRNA. Specifically, WTAP is required for the accumulation of METTL3 and METTL14 in nuclear speckles. In this paper, we briefly introduce the molecular mechanism of m⁶A modification. Then, we focus on WTAP, a component of the m⁶A methyltransferase complex, and introduce its structure, localization, and physiological functions. Finally, we describe its roles and mechanisms in cancer.

Glycolytic Inhibitors Potentiated the Activity of Paclitaxel and Their Nanoencapsulation Increased Their Delivery in a Lung Cancer Model

Antiglycolytic agents inhibit cell metabolism and modify the tumor’s microenvironment, affecting chemotherapy resistance mechanisms. In this work, we studied the effect of the glycolytic inhibitors 3-bromopyruvate (3BP), dichloroacetate (DCA) and 2-deoxyglucose (2DG) on cancer cell properties and on the multidrug resistance phenotype, using lung cancer cells as a model. All compounds led to the loss of cell viability, with different effects on the cell metabolism, migration and proliferation, depending on the drug and cell line assayed. DCA was the most promising compound, presenting the highest inhibitory effect on cell metabolism and proliferation. DCA treatment led to decreased glucose consumption and ATP and lactate production in both A549 and NCI-H460 cell lines. Furthermore, the DCA pretreatment sensitized the cancer cells to Paclitaxel (PTX), a conventional chemotherapeutic drug, with a 2.7-fold and a 10-fold decrease in PTX IC₅₀ values in A549 and NCI-H460 cell lines, respectively. To increase the intracellular concentration of DCA, thereby potentiating its effect, DCA-loaded poly(lactic-co-glycolic acid) nanoparticles were produced. At higher DCA concentrations, encapsulation was found to increase its toxicity. These results may help find a new treatment strategy through combined therapy, which could open doors to new treatment approaches.

Mitofusin-2 in cancer: Friend or foe?

Cancer is a category of disorders characterized by excessive cell proliferation with the ability to infiltrate or disseminate to other organs of the body. Mitochondrial dysfunction, as one of the most prominent hallmarks of cancer cells, has been related to the onset and development of various cancers. Mitofusin 2 (MFN2) is a major mediator of mitochondrial fusion, endoplasmic reticulum (ER)-mitochondria interaction, mitophagy and axonal transport of mitochondria. Available data have shown that MFN2, which its alterations have been associated with mitochondrial dysfunction, could affect cancer initiation and progression. In fact, it showed that MFN2 may have a double-edged sword effect on cancer fate. Precisely, it demonstrated that MFN2, as a tumor suppressor, induces cancer cell apoptosis and inhibits cell proliferation via Ca²⁺ and Bax-mediated apoptosis and increases P21 and p27 levels, respectively. It also could suppress cell survival via inhibiting PI3K/Akt, Ras-ERK1/2-cyclin D1 and mTORC2/Akt signaling pathways. On the other hand, MFN2, as an oncogene, could increase cancer invasion via snail-mediated epithelial-mesenchymal transition (EMT) and in vivo tumorigenesis. While remarkable progress has been achieved in recent decades, further exploration is required to elucidate whether MFN2 could be a friend or it's an enemy. This study aimed to highlight the different functions of MFN2 in various cancers.

Arsenic exposure elevated ROS promotes energy metabolic reprogramming with enhanced AKT-dependent HK2 expression

Exposure to inorganic or organic arsenic compounds continues to pose substantial public health concerns for hundreds of millions of people around the globe. Highly exposed individuals are susceptible to various illnesses, including impairments and cancers of the lung, liver, skin and bladder. Long-term exposure to low-dose arsenic has been identified to induce aerobic glycolysis, which contributes to cells aberrant proliferation. However, the mechanism underlying arsenic-induced aerobic glycolysis is still unclear. Here, mtDNA copy number is enhanced in arsenic-exposed populations and a positive correlation between serum HK2 and urinary total arsenic was observed in the individuals with high urine arsenic (≥ 0.032 mg/L). In a rat model of trivalent arsenic (iAs³⁺) exposure, the levels of HK2, NDUFA9 and NDUFB8 were increased in the rats treated with iAs³⁺ daily by gavage for 12 weeks than those in the control rats. Subsequently, in a low-dose arsenic exposure cell model we found that 0.2 μmol/L iAs³⁺ induced aerobic glycolysis to promote L-02 cells proliferation and inhibit apoptosis, in which HK2 played an important role. Further studies showed accumulated ROS determined the metabolic reprogramming via activating AKT and then increasing HK2 expression. On the one hand, activated AKT induced aerobic glycolysis by increasing HK2 to promote L-02 cells viability and DNA synthesis; on the other hand, phosphorylated AKT induced HK2 mitochondrial outer-membrane location with VDAC1 to inhibit apoptosis. Taken together, our results indicated that ROS induced by low-dose arsenic exposure determined energy metabolic reprogramming and acted a critical regulator for AKT-dependent HK2 expression and aerobic glycolysis.

Long non-coding RNAs play an important regulatory role in tumorigenesis and tumor progression through aerobic glycolysis

Compared to normal cells, cancer cells generate ATP mainly through aerobic glycolysis, which promotes tumorigenesis and tumor progression. Long non-coding RNAs (LncRNAs) are a class of transcripts longer than 200 nucleotides with little or without evident protein-encoding function. LncRNAs are involved in the ten hallmarks of cancer, interestingly, they are also closely associated with aerobic glycolysis. However, the mechanism of this process is non-transparent to date. Demonstrating the mechanism of lncRNAs regulating tumorigenesis and tumor progression through aerobic glycolysis is particularly critical for cancer therapy, and may provide novel therapeutic targets or strategies in cancer treatment. In this review, we discuss the role of lncRNAs and aerobic glycolysis in tumorigenesis and tumor progression, and further explore their interaction, in hope to provide a novel therapeutic target for cancer treatment.

New insights into the prognosis of intraocular malignancy: Interventions for association mechanisms between cancer and diabetes

The intraocular malignancies, which mostly originate from the retina and uvea, exhibit a high incidence of blindness and even death. Uveal melanoma (UM) and retinoblastoma (RB) are the most common intraocular malignancies in adults and children, respectively. The high risks of distant metastases lead to an extremely poor prognosis. Nowadays, various epidemiological studies have demonstrated that diabetes is associated with the high incidence and mortality of cancers, such as liver cancer, pancreatic cancer, and bladder cancer. However, the mechanisms and interventions associated with diabetes and intraocular malignancies have not been reviewed. In this review, we have summarized the associated mechanisms between diabetes and intraocular malignancy. Diabetes mellitus is a chronic metabolic disease characterized by prolonged periods of hyperglycemia. Recent studies have reported that the abnormal glucose metabolism, insulin resistance, and the activation of the IGF/insulin-like growth factor-1 receptor (IGF-1R) signaling axis in diabetes contribute to the genesis, growth, proliferation, and metastases of intraocular malignancy. In addition, diabetic patients are more prone to suffer severe complications and poor prognosis after radiotherapy for intraocular malignancy. Based on the common pathogenesis shared by diabetes and intraocular malignancy, they may be related to interventions and treatments. Therefore, interventions targeting the abnormal glucose metabolism, insulin resistance, and IGF-1/IGF-1R signaling axis show therapeutic potentials to treat intraocular malignancy.

The hexokinase "HKDC1" interaction with the mitochondria is essential for liver cancer progression

Liver cancer (LC) is the fourth leading cause of death from cancer malignancies. Recently, a putative fifth hexokinase, hexokinase domain containing 1 (HKDC1), was shown to have significant overexpression in LC compared to healthy liver tissue. Using a combination of in vitro and in vivo tools, we examined the role of HKDC1 in LC development and progression. Importantly, HKDC1 ablation stops LC development and progression via its action at the mitochondria by promoting metabolic reprogramming and a shift of glucose flux away from the TCA cycle. HKDC1 ablation leads to mitochondrial dysfunction resulting in less cellular energy, which cannot be compensated by enhanced glucose uptake. Moreover, we show that the interaction of HKDC1 with the mitochondria is essential for its role in LC progression, and without this interaction, mitochondrial dysfunction occurs. As HKDC1 is highly expressed in LC cells, but only to a minimal degree in hepatocytes under normal conditions, targeting HKDC1, specifically its interaction with the mitochondria, may represent a highly selective approach to target cancer cells in LC.

Research progress on the interaction between long non‑coding RNAs and RNA‑binding proteins to influence the reprogramming of tumor glucose metabolism (Review)

As epigenetic regulators, long non-coding RNAs (lncRNAs) are involved in various important regulatory processes and typically interact with RNA-binding proteins (RBPs) to exert their core functional effects. An increasing number of studies have demonstrated that lncRNAs can regulate the occurrence and development of cancer through a variety of complex mechanisms and can also participate in tumor glucose metabolism by directly or indirectly regulating the Warburg effect. As one of the metabolic characteristics of tumor cells, the Warburg effect provides a large amount of energy and numerous intermediate products to meet the consumption demands of tumor metabolism, providing advantages for the occurrence and development of tumors. The present review article summarizes the regulatory effects of lncRNAs on the reprogramming of glucose metabolism after interacting with RBPs in tumors. The findings discussed herein may aid in the better understanding of the pathogenesis of malignancies, and may provide novel therapeutic targets, as well as new diagnostic and prognostic markers for human cancers.

FOXM1 regulates glycolysis and energy production in multiple myeloma

The transcription factor, forkhead box M1 (FOXM1), has been implicated in the natural history and outcome of newly diagnosed high-risk myeloma (HRMM) and relapsed/refractory myeloma (RRMM), but the mechanism with which FOXM1 promotes the growth of neoplastic plasma cells is poorly understood. Here we show that FOXM1 is a positive regulator of myeloma metabolism that greatly impacts the bioenergetic pathways of glycolysis and oxidative phosphorylation (OxPhos). Using FOXM1-deficient myeloma cells as principal experimental model system, we find that FOXM1 increases glucose uptake, lactate output, and oxygen consumption in myeloma. We demonstrate that the novel 1,1-diarylethylene small-compound FOXM1 inhibitor, NB73, suppresses myeloma in cell culture and human-in-mouse xenografts using a mechanism that includes enhanced proteasomal FOXM1 degradation. Consistent with the FOXM1-stabilizing chaperone function of heat shock protein 90 (HSP90), the HSP90 inhibitor, geldanamycin, collaborates with NB73 in slowing down myeloma. These findings define FOXM1 as a key driver of myeloma metabolism and underscore the feasibility of targeting FOXM1 for new approaches to myeloma therapy and prevention.

CRISPR/Cas9 Screens Reveal that Hexokinase 2 Enhances Cancer Stemness and Tumorigenicity by Activating the ACSL4-Fatty Acid β-Oxidation Pathway

Metabolic reprogramming is often observed in carcinogenesis, but little is known about the aberrant metabolic genes involved in the tumorigenicity and maintenance of stemness in cancer cells. Sixty-seven oncogenic metabolism-related genes in liver cancer by in vivo CRISPR/Cas9 screening are identified. Among them, acetyl-CoA carboxylase 1 (ACC1), aldolase fructose-bisphosphate A (ALDOA), fatty acid binding protein 5 (FABP5), and hexokinase 2 (HK2) are strongly associated with stem cell properties. HK2 further facilitates the maintenance and self-renewal of liver cancer stem cells. Moreover, HK2 enhances the accumulation of acetyl-CoA and epigenetically activates the transcription of acyl-CoA synthetase long-chain family member 4 (ACSL4), leading to an increase in fatty acid β-oxidation activity. Blocking HK2 or ACSL4 effectively inhibits liver cancer growth, and GalNac-siHK2 administration specifically targets the growth of orthotopic tumor xenografts. These results suggest a promising therapeutic strategy for the treatment of liver cancer.

3‑Bromopyruvic acid regulates glucose metabolism by targeting the c‑Myc/TXNIP axis and induces mitochondria‑mediated apoptosis in TNBC cells

Aerobic glycolysis is commonly observed in tumor cells, including triple-negative breast cancer (TNBC) cells, and the rate of aerobic glycolysis is higher in TNBC cells than in non-TNBC cells. Hexokinase 2 (HK2) is a key enzyme in the glycolytic pathway and a target of the transcription factor c-Myc, which is highly expressed in TNBC and promotes aerobic glycolysis by enhancing HK2 expression. As an inhibitor of HK2, 3-bromopyruvic acid (3-BrPA) exhibits good therapeutic efficacy in intrahepatic and extrahepatic tumors and inhibits the proliferation of human tumor cells with high expression levels of c-Myc in vivo and in vitro. In addition, 3-BrPA combines with photodynamic therapy to inhibit TNBC cell migration. Thioredoxin-interacting protein (TXNIP) competes with c-Myc to reduce glucose consumption in tumor cells to restrain cell proliferation. A comparative analysis was performed in the present study in TNBC (HCC1143) and non-TNBC (MCF-7) cell lines to explore the effect of 3-BrPA on energy metabolism in TNBC cells and to investigate the possible mechanism of action. Cell viability and apoptosis were detected through Cell Counting Kit-8 and flow cytometry assays, respectively. Expression levels of HK2, glucose transporter 1, TXNIP, c-Myc and mitochondria-regulated apoptosis pathway proteins were measured through western blotting. 3-BrPA inhibited cell proliferation, downregulated c-Myc and HK2 expression, and upregulated TXNIP expression in TNBC cells, but it doesn't have the same effect on non-TNBC cells. Furthermore, 3-BrPA induced the typical manifestations of mitochondrial-mediated apoptosis such as decreasing Bcl-2 expression and increasing Bax, Cyt-C and Caspase-3 expression. The present results suggested that 3-BrPA promoted TXNIP protein expression and reduced HK2 expression in TNBC cells by downregulating c-Myc expression, inhibiting glycolysis including suppressing lactate generation, intracellular ATP generation and HK activity, inducing mitochondrial-mediated apoptosis and eventually suppressing TNBC cell proliferation. These findings may reveal a novel therapeutic target for the clinical treatment of TNBC.

Integration of glucose and cardiolipin anabolism confers radiation resistance of HCC

BACKGROUND AND AIMS

Poor response to ionizing radiation (IR) due to resistance remains a clinical challenge. Altered metabolism represents a defining characteristic of nearly all types of cancers. However, how radioresistance is linked to metabolic reprogramming remains elusive in hepatocellular carcinoma (HCC).

APPROACH AND RESULTS

Baseline radiation responsiveness of different HCC cells were identified and cells with acquired radio-resistance were generated. By performing proteomics, metabolomics, metabolic flux, and other functional studies, we depicted a metabolic phenotype that mediates radiation resistance in HCC, whereby increased glucose flux leads to glucose addiction in radioresistant HCC cells and a corresponding increase in glycerophospholipids biosynthesis to enhance the levels of cardiolipin. Accumulation of cardiolipin dampens the effectiveness of IR by inhibiting cytochrome c release to initiate apoptosis. Mechanistically, mammalian target of rapamycin complex 1 (mTORC1) signaling-mediated translational control of hypoxia inducible factor-1α (HIF-1α) and sterol regulatory element-binding protein-1 (SREBP1) remodels such metabolic cascade. Targeting mTORC1 or glucose to cardiolipin synthesis, in combination with IR, strongly diminishes tumor burden. Finally, activation of glucose metabolism predicts poor response to radiotherapy in cancer patients.

CONCLUSIONS

We demonstrate a link between radiation resistance and metabolic integration and suggest that metabolically dismantling the radioresistant features of tumors may provide potential combination approaches for radiotherapy in HCC.

Potential of Novel Methyl Jasmonate Analogs as Anticancer Agents to Metabolically Target HK-2 Activity in Glioblastoma Cells

Change in the energy metabolism of cancer cells, which display significant differences compared to normal cells, is a rising phenomenon in developing new therapeutic approaches against cancers. One of the metabolic enzymes, hexokinase-II (HK-II) is involved in glycolysis, and inhibiting the HK-II activity may be a potential metabolic target for cancer therapy as most of the drugs in clinical use act on DNA damage. Methyl jasmonate (MJ) is one of the compounds blocking HK-II activity in cancer cells. In a previous study, we showed that the novel MJ analogs inhibit HK-II activity through VDAC detachment from the mitochondria. In this study, to evaluate the potential of targeting HK-2 activity, through patient cohort analysis, we first determined HK-2 expression levels and prognostic significance in highly lethal glioblastoma (GBM) brain tumor. We then examined the in vitro therapeutic effects of the novel analogs in the GBM cells. Here, we report that, among all, compound-10 (C-10) showed significant in vitro therapeutic efficacy as compared to MJ which is in use for preclinical and clinical studies. Afterward, we analyzed cell death triggered by C-10 in two different GBM cell lines. We found that C-10 treatment increased the apoptotic/necrotic cells and autophagy in GBM cells. The newly developed analog, C-10, was found to be lethal against GBM by the activation of cell death authorities, mostly in a necrotic and autophagic fashion at the early stages of the treatment. Considering that possibly decreased intracellular ATP levels by C-10 mediated inhibition of HK-2 activity and disabled VDAC interaction, a more detailed analysis of HK-2 inhibition-mediated cell death can provide a deep understanding of the mechanism of action on the oncosis/necroptosis axis. These findings provide an option to design clinically relevant and effective novel HK-II inhibitors and suggest novel MJ analogs to further study them as potential anticancer agents against GBM.

Sodium butyrate inhibits aerobic glycolysis of hepatocellular carcinoma cells via the c‐myc/hexokinase 2 pathway

Aerobic glycolysis is a well‐known hallmark of hepatocellular carcinoma (HCC). Hence, targeting the key enzymes of this pathway is considered a novel approach to HCC treatment. The effects of sodium butyrate (NaBu), a sodium salt of the short‐chain fatty acid butyrate, on aerobic glycolysis in HCC cells and the underlying mechanism are unknown. In the present study, data obtained from cell lines with mouse xenograft model revealed that NaBu inhibited aerobic glycolysis in the HCC cells in vivo and in vitro. NaBu induced apoptosis while inhibiting the proliferation of the HCC cells in vivo and in vitro. Furthermore, the compound inhibited the release of lactate and glucose consumption in the HCC cells in vitro and inhibited the production of lactate in vivo. The modulatory effects of NaBu on glycolysis, proliferation and apoptosis were related to its modulation of hexokinase 2 (HK2). NaBu downregulated HK2 expression via c‐myc signalling. The upregulation of glycolysis in the HCC cells induced by sorafenib was impeded by NaBu, thereby enhancing the anti‐HCC effect of sorafenib in vitro and in vivo. Thus, NaBu inhibits the expression of HK2 to downregulate aerobic glycolysis and the proliferation of HCC cells and induces their apoptosis via the c‐myc pathway.

Developing a 5-gene prognostic signature for cervical cancer by integrating mRNA and copy number variations

Background

Cervical cancer is frequently detected gynecological cancer all over the world. This study was designed to develop a prognostic signature for an effective prediction of cervical cancer prognosis.

Methods

Differentially expressed genes (DEGs) were identified based on copy number variation (CNV) data and expression profiles from different databases. A prognostic model was constructed and further optimized by stepwise Akaike information criterion (stepAIC). The model was then evaluated in three groups (training group, test group and validation group). Functional analysis and immune analysis were used to assess the difference between high-risk and low-risk groups.

Results

The study developed a 5-gene prognostic model that could accurately classify cervical cancer samples into high-risk and low-risk groups with distinctly different prognosis. Low-risk group exhibited more favorable prognosis and higher immune infiltration than high-risk group. Both univariate and multivariate Cox regression analysis showed that the risk score was an independent risk factor for cervical cancer.

Conclusions

The 5-gene prognostic signature could serve as a predictor for identifying high-risk cervical cancer patients, and provided potential direction for studying the mechanism or drug targets of cervical cancer. The integrated analysis of CNV and mRNA expanded a new perspective for exploring prognostic signatures in cervical cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09291-z.

Cancer on-target: Selective enhancement of 3-bromopyruvate action by an electromagnetic field in vitro

Cancer is one of the leading causes of death in the modern world. Nowadays, most often treatment methods used in clinical oncology are drug therapies applied as monotherapy or combined therapy. Additionally, recent studies focus on developing approaches with the use of a drug in combination with other factors, not only chemical, to improve the probability and magnitude of therapeutic responses and reduce the possibility of chemoresistance. Such a promising factor seems to be an electromagnetic field (EMF) application. Here, we tested the effect of continuous or pulsed EMF on human cancer cells of different origin treated or not with 3-bromopyruvate, a small and powerful alkylating agent with a broad spectrum of anticancer activities. We provide strong evidence suggesting that ELF-EMF potentiates the anti-cancer activity of 3BP in human cancer cells through inhibition of TNFα secretion leading to irreversible p21/p27-dependent G2/M cell cycle arrest and finally cancer cell death. Our findings suggest a novel approach combining pharmacotherapy with ELF-EMF. In conclusion, electromagnetic field seems to be a potential modulator of anti-cancer efficacy of 3BP while combined therapy offers off-target activity. These features contribute to the development of innovative therapeutic strategies for cancer treatment.

Polychlorinated biphenyl quinone exposure promotes breast cancer aerobic glycolysis: An in vitro and in vivo examination

Polychlorinated biphenyls (PCBs) were classified as group I carcinogenic to humans, as their toxicological mechanisms have been associated with cancer initiation and promotion. However, whether PCBs have effects on cancer progression are still largely veiled. Here, we for the first time discovered that a PCB quinone-type metabolite, namely PCB29-pQ, exposure significantly promoted aerobic glycolysis, a hallmark property of metabolic reprogramming in cancer progression. PCB29-pQ exposure activated corresponding glucose transporter type 1 (GLUT1)/integrin β1/Src/focal adhesion kinase (FAK) signaling pathway in breast cancer MDA-MB-231 cells. Conversely, the inhibition of GLUT1 reversed this effect, as well as the ability of migration and invasion of MDA-MB-231 cells. In addition, PCB29-pQ-induced breast cancer metastasis in 4T1-luc cell inoculated nude mice is repressed by GLUT1 inhibition. Overall, our results demonstrated a novel mechanism that PCB29-pQ exposure promotes aerobic glycolysis in both in vitro and in vivo breast cancer models in a GLUT1-dependent fashion, which may provide a strategy to prevent breast cancer cell spread.

Altered Basal Lipid Metabolism Underlies the Functional Impairment of Naive CD8+ T Cells in Elderly Humans

Aging is associated with functional deficits in the naive T cell compartment, which compromise the generation of de novo immune responses against previously unencountered Ags. The mechanisms that underlie this phenomenon have nonetheless remained unclear. We found that naive CD8+ T cells in elderly humans were prone to apoptosis and proliferated suboptimally in response to stimulation via the TCR. These abnormalities were associated with dysregulated lipid metabolism under homeostatic conditions and enhanced levels of basal activation. Importantly, reversal of the bioenergetic anomalies with lipid-altering drugs, such as rosiglitazone, almost completely restored the Ag responsiveness of naive CD8+ T cells. Interventions that favor lipid catabolism may therefore find utility as adjunctive therapies in the elderly to promote vaccine-induced immunity against targetable cancers and emerging pathogens, such as seasonal influenza viruses and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Quantitative Proteome Analysis in Response to Glucose Concentration in C2C12 Myotubes

Glucose is important for the maintenance of muscle function; however, it is still unclear how changes in glucose concentration affect muscle. Here, we analyzed the effect of glucose concentration on protein expression under different glucose concentration media in C2C12 myotubes. First, we performed proteome analysis in C2C12 myotubes cultured in Low (1.0 g/L), Medium (2.0 g/L), and High (4.5 g/L) glucose media. Proteome analysis revealed 113 proteins were significantly changed in group cultured in Low or Medium glucose media compared to group cultured in High glucose media. Furthermore, glycolysis, oxidative phosphorylation, and fatty acid metabolism were increased in the Medium and Low groups. Among these pathways, HK2, PFKP, NDUFA11, and FABP3 were especially upregulated proteins in Low and Medium groups. In this context, ATP production in C2C12 myotubes cultured in Low and Medium glucose media was increased. There was no significant change in myotubes morphology and myogenic differentiation factors in all groups. Finally, we examined the effect on glucose concentration in culture media on myosin isoforms expression by qRT-PCR. As a result, Myh2 and Myh4 were significantly increased in Low and Medium conditions. Altogether, Low and Medium glucose conditions induced Myh expression probably via enhancement glucose utilization.

Exosome-delivered circular RNA DLGAP4 induces chemoresistance via miR-143-HK2 axis in neuroblastoma

Accumulating evidence validates that aerobic glycolysis is involved in chemotherapy resistance in human malignant tumors. In the present study, we explored the role of exosome-delivered circular RNA DLGAP4 (circDLGAP4), a novel identified circRNAs, in the chemoresistance of neuroblastoma (NB) cells. Our study demonstrated that doxorubicin-resistant cells expressed higher HK2, accompanied with enhanced glycolysis. In addition, circDLGAP4 was validated to act as a sponge for the HK2-targeting miR-143. As a molecular cargo, exosomes were found to deliver circDLGAP4 from doxorubicin-resistant cells to the sensitive cells. Functionally, exosomal circDLGAP4 enhanced glycolysis and drug resistance via regulating miR-143 and HK2 in NB cells. Consistently, upregulation of HK2 induced by circDLGAP4 or miR-143 inhibitors produced the similar malignant transformation in NB cells. However, knockdown of circDLGA P4 could reversed the drug resistance in the recipient cells. In conclusion, these findings demonstrate that exosome-delivered circDLGAP4 promotes the glycolysis, proliferation, and invasion of sensitive NB cells by regulating miR-143 and HK2, providing a novel link between drug resistance and circDLGAP4/miR-143/HK2 axis in drug-resistant NB.