Glucose Transporter 1 Inhibitors Induce Autophagy and Synergize With Lenvatinib in Thyroid Cancer Cells.

BACKGROUND: Less differentiated thyroid cancer may upregulate the expression of glucose transporter 1 (GLUT1) and increase glycolytic activity. However, it is uncertain whether GLUT1 can be used as a target for therapy. METHODS: Thyroid cancer cell lines were treated with two different GLUT1 inhibitors, STF-31 and BAY-876. Functional assays were conducted to evaluate the effects of these inhibitors on cell biology. RESULTS: GLUT1 inhibitors dose-dependently decreased cell growth and clonogenicity of thyroid cancer cells. Cell cycle analysis showed that these inhibitors caused G2/M arrest instead of apoptosis. Additionally, treatment with GLUT1 inhibitors led to the activation of autophagy. In both the Transwell and spheroid models, GLUT1 inhibitors significantly suppressed cell invasiveness. Moreover, GLUT1 inhibitors demonstrated synergistic interactions when combined with lenvatinib. CONCLUSIONS: Treatment with GLUT1 inhibitors activates autophagy and provokes cell cycle arrest, accompanied by a decrease in colony formation and invasive capacity in thyroid cancer cells.

Digitonin-Loaded Nanoscale Metal-Organic Framework for Mitochondria-Targeted Radiotherapy-Radiodynamic Therapy and Disulfidptosis.

The efficacy of radiotherapy (RT) is limited by inefficient X-ray absorption and reactive oxygen species generation, upregulation of immunosuppressive factors, and a reducing tumor microenvironment (TME). Here, the design of a mitochondria-targeted and digitonin (Dig)-loaded nanoscale metal-organic framework, Th-Ir-DBB/Dig, is reported to overcome these limitations and elicit strong antitumor effects upon low-dose X-ray irradiation. Built from Th6O4(OH)4 secondary building units (SBUs) and photosensitizing Ir(DBB)(ppy)2 2+ (Ir-DBB, DBB = 4,4'-di(4-benzoato)-2,2'-bipyridine; ppy = 2-phenylpyridine) ligands, Th-Ir-DBB exhibits strong RT-radiodynamic therapy (RDT) effects via potent radiosensitization with high-Z SBUs for hydroxyl radical generation and efficient excitation of Ir-DBB ligands for singlet oxygen production. Th-Ir-DBB/Dig releases digitonin in acidic TMEs to trigger disulfidptosis of cancer cells and sensitize cancer cells to RT-RDT through glucose and glutathione depletion. The released digitonin simultaneously downregulates multiple immune checkpoints in cancer cells and T cells through cholesterol depletion. As a result, Th-Ir-DBB/dig plus X-ray irradiation induces strong antitumor immunity to effectively inhibit tumor growth in mouse models of colon and breast cancer.

Hyaluronan and Glucose Dual-targeting Probe: Synthesis and Application.

In this work, we developed a dual-targeting probe consisted of well-defined hyaluronan (HA) oligosaccharide and glucose (Glc) labeled with Rhodamine B (HGR). The probe was designed to enhance tumor targeting both in vitro and in vivo, by simultaneously targeting CD44 and Glc transporter 1 (GLUT1). The HA oligosaccharide component was crucial for accurately assessing the impact of sugar chain structure on targeting efficacy, while its unoccupied carboxyl groups could minimize interference with HA's binding affinity to CD44. In vitro studies demonstrated that HGR possessed remarkable cytocompatibility and superior targeting abilities compared to single-targeting probes. It displayed a marked preference for CD44high/GLUT1high cells rather than CD44low/GLUT1low cells. In vivo studies using murine models further confirmed the significantly enhanced targeting efficacy and excellent biocompatibility of HGR. Therefore, this designed dual-targeting probe holds potential for clinical tumor detection.

Gestational exposure to BPA alters the expression of glucose and lipid metabolic mediators in the placenta: role in programming offspring for obesity.

Bisphenol A (BPA) exposure during pregnancy is known to predispose offspring to obesity in later life. Our previous studies demonstrated obesogenic effects in BPA-exposed offspring, including excess body fat, increased feed efficiency, adipocyte hypertrophy, and altered leptin signaling. However, the role of the placenta in mediating these effects remained unclear. This study investigates the mechanisms by which BPA exposure affects placental glucose and lipid transporters and their impact on offspring adiposity in Wistar rats. Dams were orally gavaged with BPA [0.4 (low dose-LD) and 4.0 (high dose-HD) µg/kg body weight] from gestational day (gD) 4 to 14. Gestational exposure to LD BPA increased the expression of 11ß hydroxysteroid dehydrogenase 1 (11ß HSD1) and estrogen receptor alpha (ERα) proteins (p<0.05) in the placenta compared to control and HD BPA. Similar changes were observed in the expression of mTOR signaling mediators, fatty acid transporters, and intracellular fatty acid-binding proteins. There were no changes in the dam's body weight or lipid and glucose profiles. However, there was a dose dependent increase in glucose transporter (GLUT1) expression in the placenta. While LD BPA increased hexokinase 2 expression in the placenta, HD BPA had no effect. Both doses of BPA increased IL6 expression, but only LD BPA exposure increased PPAR-gamma expression. Additionally, BPA exposure induced ADRP expression and localization, suggesting potential lipid overload in the placenta. Furthermore, BPA exposure altered the placental epigenetic profile, with increased expression of DNA methyltransferases (DNMTs). Overall, gestational BPA exposure led to dose-specific alterations in placental glucose and lipid metabolic activities, possibly playing an role in increasing the supply of these macronutrients to the fetus and predisposing the offspring to obesity.

Hypoxia-Inducible Factor 1-Alpha (HIF-1α): An Essential Regulator in Cellular Metabolic Control.

The element that causes hypoxia when the von Hippel-Lindau (VHL) protein is not functioning is hypoxia-inducible factor 1-alpha (HIF-1α), which is the essential protein linked to cell control under hypoxia. Consequently, in situations where cells are oxygen-deficient, HIF-1α carries out a variety of essential functions. Citations to relevant literature support the notion that HIF-1α regulates the mitochondrial and glycolytic pathways, as well as the transition from the former to the latter. Cells with limited oxygen supply benefit from this change, which is especially beneficial for the inhibition of the mitochondrial electron transport chain and enhanced uptake of glucose and lactate. During hypoxic stress, HIF-1α also controls proline and glycolytic transporters such as lactate dehydrogenase A (LDHA) and glucose transporter 1 (GLUT1). These mechanisms help the cell return to homeostasis. Therefore, through metabolic change promoting adenosine triphosphate (ATP) synthesis and reducing reactive oxygen species (ROS) creation, HIF-1α may have a role in reducing oxidative stress in cells. This evidence, which describes the function of HIF-1α in many molecular pathways, further supports the notion that it is prognostic and that it contributes to hypoxic cell adaption. Understanding more about disorders, including inflammation, cancer, and ischemia, is possible because of HIF-1α's effect on metabolic changes. Gaining knowledge about the battle between metabolism, which is directed by HIF-1α, would help advance the research on pathophysiological situations involving dysregulated hypoxia and metabolism.

Hypoxia-Regulated Proteins: Expression in Endometrial Cancer and Their Association with Clinicopathologic Features.

BACKGROUND: Hypoxia-regulated proteins (HIF-1α and GLUT-1) have been identified as prognostic markers in various cancers; however, their role in endometrial cancer remains unclear. This study aimed to evaluate HIF-1α and GLUT-1 expression in endometrial cancer and correlate their expression with clinicopathological features. MATERIALS AND METHODS: A tissue microarray (TMA) was constructed using specimens from a retrospective cohort of 51 endometrial cancer patients who underwent hysterectomy at the Gyeongsang National University Hospital between 2002 and 2009. Clinicopathologic data were collected from electronic medical records, and HIF-1α and GLUT-1 expressions were assessed in the tumor tissue. RESULTS: GLUT-1 expression in endometrial cancer was categorized as mosaic, central, or diffuse. Most patients (56.0%) exhibited a central pattern, followed by diffuse (32.0%) and mosaic (12.0%) patterns. GLUT-1 expression was not significantly associated with histologic grade (p = 0.365). HIF-1α expression in immune cells, but not tumor cells, was significantly associated with a higher histologic grade. A higher proportion of HIF-1α-positive immune cells, using both thresholds (≤1% vs. >1% and ≤5% vs. >5%), was significantly associated with higher histologic grade (p = 0.032 and p = 0.048, respectively). In addition, a higher proportion of HIF-1α-positive immune cells was significantly associated with a diffuse GLUT-1 expression pattern using >5% as a threshold. There were no significant differences in the proportion of HIF-1α-positive immune cells between groups stratified by age, tumor size, or invasion depth, regardless of whether the 1% or 5% threshold for HIF-1α positivity was used. CONCLUSIONS: A higher proportion of HIF-1α-positive immune cells is associated with endometrial cancers with higher histologic grade and diffuse GLUT1 expression patterns. These findings suggest a potential role for HIF-1α as a prognostic marker and highlight the need for further studies into the role of HIF-1α in the tumor microenvironment.

Acidic Pepsin Affects Laryngeal Carcinoma Cell Growth and Invasion Through Glycolysis.

OBJECTIVE: The pathogenic mechanism underlying the effects of acidic pepsin in laryngeal cancer remains unclear. This study investigated whether acidic pepsin influences Glut-1 expression and glycolytic activity in laryngeal carcinoma cells and whether it plays a role in the growth and migration of these cells through glycolysis. STUDY DESIGN: In vitro study. SETTING: A university-affiliated hospital. METHODS: Laryngeal carcinoma TU 212 and TU 686 cells were treated with acidic pepsin and 2-deoxy-d-glucose (2-DG), then transfected with Glut-1 small interfering RNA (siRNA). Glucose uptake was detected by a radioimmunoassay counter, lactate secretion was detected by a lactic acid kit, and Glut-1 expression was detected by western blotting. Cell viability, migration and invasion, and clonal formation were assessed using the Cell Counting Kit-8, Transwell chamber, and clonal formation assays, respectively. RESULTS: Acidic pepsin significantly increased Glut-1 expression in laryngeal carcinoma cells compared with the control group (P < .01). It also significantly enhanced 18F-fluorodeoxyglucose (Cin/Cout) uptake, lactate secretion, cell viability, migration, invasion, and clonal formation in laryngeal carcinoma cells compared with the control group (P < .01). The glycolytic inhibitor 2-DG and Glut-1 siRNA significantly reversed the effects of acidic pepsin on laryngeal carcinoma cells (P < .01). CONCLUSION: Acidic pepsin enhances the growth and migration of laryngeal carcinoma cells by upregulating Glut-1, thus promoting glycolysis.

Guía mexicana para el diagnóstico y el tratamiento del hemangioma infantil.

Infantile hemangioma is a benign vascular tumor, the most common in childhood, whose natural evolution is the disappearance of the lesion in the pediatric age and which has effective and safe treatments that limit its growth and favor its disappearance at younger ages. Infantile hemangioma continues to be a reason for attention to complications, due to erroneous diagnoses, lack of knowledge of the condition, late referral or fear of the effects of the medications used for its treatment. Furthermore, its presence is normalized without taking into account that it can cause uncertainty, anxiety, feelings of guilt and, as a consequence, a significant impact on the quality of life, mainly in the parents or caregivers of the child. The need for a clinical practice guideline in our country arises from the high presentation of late-remitted complications in infantile hemangioma even with the availability of adequate treatments, the continuous evolution of medicine and the appearance of new evidence. Throughout the guide you will find recommendations regarding the diagnosis, treatment and follow-up of patients with infantile hemangioma, taking into account the paraclinical tests that can be performed, topical or systemic management options, as well as adjuvant therapies. For the first time, objective tools for patient follow-up are included in a guide for the management of infantile hemangioma, as well as to help the first contact doctor in timely referral.

El hemangioma infantil es un tumor vascular benigno, el más frecuente de la infancia, cuya evolución natural favorece la desaparición de la lesión en la misma edad pediátrica y que cuenta con tratamientos eficaces y seguros que limitan su crecimiento y favorecen su desaparición a edades más tempranas. Continúa siendo motivo de atención de complicaciones, debido a diagnósticos erróneos, desconocimiento del padecimiento, referencia tardía o temor de los efectos de los fármacos utilizados para su tratamiento. Además, se normaliza su presencia sin tomar en cuenta que puede llegar a causar incertidumbre, ansiedad, sentimientos de culpa y, como consecuencia, importante afectación de la calidad de vida, principalmente en los padres o cuidadores del niño. La necesidad de una guía de práctica clínica en nuestro país surge ante la alta presentación de complicaciones del hemangioma infantil referidas de manera tardía aun con la disponibilidad de tratamientos adecuados, la evolución continua de la medicina y la aparición de nueva evidencia. A lo largo de la guía se encontrarán recomendaciones en relación con el diagnóstico, el tratamiento y el seguimiento de los pacientes con hemangioma infantil, tomando en cuenta los paraclínicos que pueden realizarse, las opciones de manejo tópico o sistémico, y las terapias adyuvantes. Por primera vez se incluyen en una guía para el manejo del hemangioma infantil herramientas objetivas para el seguimiento de los pacientes, así como para ayudar al médico de primer contacto en su referencia oportuna.

Bone marrow derived mesenchymal stem cells restored GLUT1 expression in the submandibular salivary glands of ovariectomized rats.

OBJECTIVE: Loss of ovarian function in menopause is commonly associated with salivary gland dysfunction. The aim is to study the possible therapeutic effect of bone marrow mesenchymal stem cells (BM-MSCs) on the altered structure of the submandibular salivary glands (SMGs) of ovariectomized rats. DESIGN: Twenty-four female, adult, Wistar rats were used and distributed into three groups (8 rats/group). The control group included sham-operated rats. The ovariectomized group consisted of rats with removed ovaries. The third group consisted of ovariectomized rats received injections, via tail, of MSCs extracted from bone marrow of 3-weeks-old rat hind limb (BM-MSC group). Four weeks after BM-MSC transplantation, the bone mineral density (BMD) of the femur was detected. The SMG was dissected and processed for histological, immunohistochemical, and histomorphometric analyses. RESULTS: The ovariectomized rats depicted low BMD in the femur. The SMG acini revealed atrophy. The ductal and acinar cells depicted vacuolization and abnormal nuclear histology. GLUT1 immunostaining was decreased in SMG ducts. The BM-MSC group resumed the normal SMG histology and GLUT1 immunolabelling. CONCLUSIONS: BM-MSC therapy restored the normal SMG structure and GLUT1 immunostaining in the treated ovariectomized rats, suggesting improved glucose transporting function.

In-silico screening of bioactive compounds of Moringa oleifera as potential inhibitors targeting HIF-1α/VEGF/GLUT-1 pathway against Breast Cancer.

OBJECTIVES: Breast cancer is among the most heterogeneous and aggressive diseases and a foremost cause of death in women globally. Hypoxic activation of HIF-1α in breast cancers triggers the transcription of a battery of genes encoding proteins that facilitate tumor growth and metastasis and is correlated with a poor prognosis. Based on the reported cytotoxic and anti-cancer properties of Moringa oleifera (Mo), this study explores the inhibitory effect of bioactive compounds from M. oleifera and breast cancer target proteins HIF-1α, VEGF, and GLUT-1 in silico. METHODS: The X-ray crystallographic structures of HIF-1α, VEGF, and GLUT1 were sourced from the Protein Data Bank (PDB) and docked with 70 3D PubChem structures of bioactive compounds of M. oleifera using AutoDock Vina, and binding modes were analyzed using Discovery Studio. Five compounds with the highest binding energies were selected and further drug-likeness, oral bioavailability, ADME, and toxicity profiles were analyzed using SwissADME, ADMETSaR, and ADMETlab 3.0 web server. RESULTS: Out of the screened 70 bioactive compounds, the top five compounds with the best binding energies were identified namely Apigenin, Ellagic Acid, Isorhamnetin, Luteolin, and Myricetin with each receptor. Molecular docking results indicated that the ligands interact strongly with the target HIF-1α, VEGF, and GLUT-1 receptors through hydrogen bonds and hydrophobic interactions. These compounds showed favorable drug-like and pharmacokinetic properties, possessed no substantial toxicity, and were fairly bioavailable. CONCLUSIONS: Results suggested that the compounds possess strong potential in developing putative lead compounds targeting HIF-1α that are safe natural plant-based drugs against breast cancer.

Ginsenoside CK cooperates with bone mesenchymal stem cells to enhance angiogenesis post-stroke via GLUT1 and HIF-1α/VEGF pathway.

The transplantation of bone marrow mesenchymal stem cells (MSCs) in stroke is hindered by the restricted rates of survival and differentiation. Ginsenoside compound K (CK), is reported to have a neuroprotective effect and regulate energy metabolism. We applied CK to investigate if CK could promote the survival of MSCs and differentiation into brain microvascular endothelial-like cells (BMECs), thereby alleviating stroke symptoms. Therefore, transwell and middle cerebral artery occlusion (MCAO) models were used to mimic oxygen and glucose deprivation (OGD) in vitro and in vivo, respectively. Our results demonstrated that CK had a good affinity for GLUT1, which increased the expression of GLUT1 and the production of ATP, facilitated the proliferation and migration of MSCs, and activated the HIF-1α/VEGF signaling pathway to promote MSC differentiation. Moreover, CK cooperated with MSCs to protect BMECs, promote angiogenesis and vascular density, enhance neuronal and astrocytic proliferation, thereby reducing infarct volume and consequently improving neurobehavioral outcomes. These results suggest that the synergistic effects of CK and MSCs could potentially be a promising strategy for stroke.

C1GALT1 induces the carcinogenesis of thyroid cancer through regulation by miR-141-3p and GLUT1.

Core 1 ß 1,3-galactosyltransferase 1 (C1GALT1) acts as an important glycosyltransferase in the occurrence and development of tumor glycosylation. However, the regulatory mechanisms of C1GALT1 in thyroid cancer (TC) is still unclear. In this study, we discovered that the expression level of C1GALT1 was significantly increased in thyroid adenocarcinoma tissues and cell lines (p < 0.01). Meanwhile, gene silencing of C1GALT1 inhibited the proliferation (CCK-8 assay), migration (wound healing), and invasion (Transwell) of TC cells (p < 0.05). Further investigation indicated that miR-141-3p had a negative correlation with C1GALT1 and suppressed cancer carcinogenesis in TC cells. Moreover, we first found that glucose transporter 1 (GLUT1) was a downstream element of C1GALT1 and was positively correlated with C1GALT1 levels in TC. The GLUT1 could reverse the inhibitory effects of siRNA C1GALT1 on cell development (p < 0.05). These data suggest that the miR-141-3p/C1GALT1/GLUT1 axis plays an essential role during TC progression and may be a probable biomarker or therapeutic target for thyroid cancer patients.

GLUT1 promotes cell proliferation via binds and stabilizes phosphorylated EGFR in lung adenocarcinoma.

BACKGROUND: While previous studies have primarily focused on Glucose transporter type 1 (GLUT1) related glucose metabolism signaling, we aim to discover if GLUT1 promotes tumor progression through a non-metabolic pathway. METHODS: The RNA-seq and microarray data were comprehensively analyzed to evaluate the significance of GLUT1 expression in lung adenocarcinoma (LUAD). The cell proliferation, colony formation, invasion, and migration were used to test GLUT1 's oncogenic function. Co-immunoprecipitation and mass spectrum (MS) were used to uncover potential GLUT1 interacting proteins. RNA-seq, DIA-MS, western blot, and qRT-PCR to probe the change of gene and cell signaling pathways. RESULTS: We found that GLUT1 is highly expressed in LUAD, and higher expression is related to poor patient survival. GLUT1 knockdown caused a decrease in cell proliferation, colony formation, migration, invasion, and induced apoptosis in LUAD cells. Mechanistically, GLUT1 directly interacted with phosphor-epidermal growth factor receptor (p-EGFR) and prevented EGFR protein degradation via ubiquitin-mediated proteolysis. The GLUT1 inhibitor WZB117 can increase the sensitivity of LUAD cells to EGFR-tyrosine kinase inhibitors (TKIs) Gefitinib. CONCLUSIONS: GLUT1 expression is higher in LUAD and plays an oncogenic role in lung cancer progression. Combining GLUT1 inhibitors and EGFR-TKIs could be a potential therapeutic option for LUAD treatment.

Immunohistochemical Localization of Glucose Transporter GLUT1 and GLUT3 in the Testes of some Mammals / Localización Inmunohistoquímica del Transportador de Glucosa GLUT1 y GLUT3 en los Testículos de Algunos Mamíferos

SUMMARY: Glucose has an essential role in the proliferation and survival of testicular tissue. Glucose transporters (GLUTs) are responsible for glucose uptake across cell membranes. In the present work, two main isoforms GLUT1 and GLUT3 were investigated in the testes of Laboratory mouse (BALB/c), Lesser Egyptian jerboa (Jaculus jaculus), Golden hamster (Mesocricetus auratus), and Desert Hedgehog (Paraechinus aethiopicus). Immunofluorescent localization of GLUT1 and GLUT3 showed considerable species differences. The lowest expression of GLUT1 and GLUT3 was localized in the testis of Laboratory mouse (BALB/c), the highest GLUT1 localization was detected in the testis of Lesser Egyptian jerboa (Jaculus jaculus), and the highest GLUT3 immunofluorescent localization was observed in the testis of Hedgehog (Paraechinus aethiopicus). The results imply that GLUT3 is the principal glucose transporter in the studied testes, which is related to species differences. The different immunolocalization of GLUT in examined testes suggests using various transport systems for energy gain in different species.

La glucosa tiene un papel esencial en la proliferación y supervivencia del tejido testicular. Los transportadores de glucosa (GLUT) son responsables de la absorción de glucosa a través de las membranas celulares. En el presente trabajo, se investigaron dos isoformas principales GLUT1 y GLUT3 en los testículos de un ratón de laboratorio (BALB/c), un jerbo egipcio menor (Jaculus jaculus), un hámster dorado (Mesocricetus auratus) y un erizo del desierto (Paraechinus aethiopicus). La localización inmunofluorescente de GLUT1 y GLUT3 mostró diferencias considerables entre especies. La expresión más baja de GLUT1 y GLUT3 se localizó en el testículo del ratón de laboratorio (BALB/c), la localización más alta de GLUT1 se detectó en el testículo del jerbo egipcio menor (Jaculus jaculus) y la localización inmunofluorescente de GLUT3 más alta se observó en el testículo de Erizo (Paraechinus aethiopicus). Los resultados implican que GLUT3 es el principal transportador de glucosa en los testículos estudiados, lo que está relacionado con diferencias entre especies. La diferente inmunolocalización de GLUT en los testículos examinados sugiere el uso de varios sistemas de transporte para ganar energía en diferentes especies.

Tryptophan deficiency induced by indoleamine 2,3-dioxygenase 1 results in glucose transporter 1-dependent promotion of aerobic glycolysis in pancreatic cancer.

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.

Targeted blocking of EGFR and GLUT1 by compound H reveals a new strategy for treatment of triple-negative breast cancer and nasopharyngeal carcinoma.

BACKGROUND: Cytoplasmic epidermal growth factor receptor (EGFR) is overexpressed in both nasopharyngeal carcinoma (NPC) and triple-negative breast cancer (TNBC), while clinical outcome and prognosis vary greatly among patients treated with gefitinib, and all patients eventually develop resistance to this agent. Therefore, we propose a new concept for synthesizing multitarget compounds and reveal new therapeutic strategies for NPC and TNBC expressing EGFR. METHODS: Compound H was synthesized in our previous study. Molecular docking, and cell thermal shift assays (CETSAs) and drug affinity responsive target stability(DARTS) were used to confirm the binding of compound H to EGFR and GLUT1. Methylthiazolyldiphenyl-tetrazolium bromide(MTT), annexin V-PE assays, mitochondrial membrane potential (MMP) assays, and animal models were used to evaluate the inhibitory effect of compound H on TNBC cell lines. Energy metabolism tests, Western blotting, and immunofluorescence staining were performed to evaluate the synergistic effects on EGFR- and glucose transporter type 1(GLUT1)-mediated energy metabolism. RESULTS: Compound H can simultaneously act on the EGFR tyrosine kinase ATP-binding site and inhibit GLUT1-mediated energy metabolism, resulting in reductions in ATP, MMP, intra-cellular lactic acid, and EGFR nuclear transfer. The anti-tumor activity of compound H is significantly superior to the combination of GLUT1 inhibitor BAY876 and EGFR inhibitor gefitinib. Compound H has remarkable anti-proliferative effects on TNBC MDA-MB231 cells, and importantly, no obvious toxicity effects of compound H were found in vivo. CONCLUSIONS: Synergistic effects of inhibition of EGFR- and GLUT1-mediated energy metabolism by compound H may present a new strategy for the treatment of TNBC and NPC.

Study of expression of GLUT-1 in oral potentially malignant disorders and oral squamous cell carcinoma: An immuno-histochemical analysis.

Background: Glucose is the chief source of energy for cells, and glucose transporter 1 (GLUT-1) is one of the most common glucose transporters in humans. Tumour cells are known to express hypoxia-related protein, and these may allow tumour cells to survive under a sustained hypoxic environment. Surviving cells develop a more aggressive phenotype, which results in poor prognosis. Aims and Objectives: Expression and comparison of GLUT-1 in normal tissues, potentially malignant disorders (PMDs), and oral squamous cell carcinoma (OSCC) and comparison of expression in different grades of OSCC. Material and Methods: A total of 57 cases (10 normal, 17 PMD, and 30 cases of OSCC) were stained immuno-histochemically with GLUT-1. The expression was scored as 0, 1, 2, 3, and 4 for negative, mild, moderate, severe, and intense staining, respectively. Results: GLUT-1 expression was detected in all grades of OSCC. A significant correlation was found on comparing normal and OSCC, normal and PMDs, and PMD and OSCC. The expression of GLUT-1 was significant when compared with different histopathological grades of OSCC. Conclusions: Expression of GLUT-1 increased from normal to PMDs to increasing grades of OSCC and hence can be used as a prognostic predictive marker for OSCC.

Immunohistochemical evaluation of Glut1 in dentigerous cysts, odontogenic keratocysts, and ameloblastoma.

Context: Glucose uptake may be considered the rate-limiting step for the growth and metabolism of the cancer cell. Studies on GLUT1 have shown that GLUT1 is involved in cell survival and proliferation in both healthy and pathological circumstances. GLUT1 expression is regarded as one of the crucial elements in the development of local aggressiveness, tumour invasiveness, and metastasis, particularly in malignant tumours. The role of glut1 in odontogenic cysts and tumours has remained uncertain. Aim: The aim of the study is to assess the expression of Glut1 in dentigerous cysts, odontogenic keratocysts, and ameloblastoma. Settings and Design: The study was conducted in GSL Dental College. The study design was a resprospective immunohistochemical study. Methods and Material: Formalin-fixed, paraffin-embedded blocks of histologically confirmed cases (n = 50), 10 cases of odontogenic keratocysts, dentigerous cysts, ameloblastomas solid, ameloblastomas unicystic, and dental follicles each. Brown colour staining was considered as positive staining for GLUT1. Quantitative analysis was performed by counting the number of labelled cells, and semi-quantitative analysis was conducted by assigning immunostaining intensity scores. Statistical Analysis: Chi-square test was used to compare differences between the groups. A P value of ≤0.05 was considered as statistically significant. Results: Odontogenic keratocysts and unicystic ameloblastoma showed ≥50% of label cells with strong intensity of staining. Odontogenic keratocysts and solid ameloblastoma showed sub-cellular localisation of staining in the cytoplasm and membrane. Dentigerous cysts exhibited combined nucleus, cytoplasm, and membrane sub-cellular localisation of staining. Conclusions: The development of ameloblastomas, odontogenic keratocysts, and dentigerous cysts appears to be influenced by GLUT-1. Variation in its expression may aid in explanation of some of the differences in biological activity of these lesions.

Dihydroartemisinin breaks the positive feedback loop of YAP1 and GLUT1-mediated aerobic glycolysis to boost the CD8+ effector T cells in hepatocellular carcinoma.

Aerobic glycolysis is a hallmark of hepatocellular carcinoma (HCC). Dihydroartemisinin (DHA) exhibits antitumor activity towards liver cancer. Our previous studies have shown that DHA inhibits the Warburg effect in HCC cells. However, the mechanism still needs to be clarified. Our study aimed to elucidate the interaction between YAP1 and GLUT1-mediated aerobic glycolysis in HCC cells and focused on the underlying mechanisms of DHA inhibiting aerobic glycolysis in HCC cells. In this study, we confirmed that inhibition of YAP1 expression lowers GLUT1-mediated aerobic glycolysis in HCC cells and enhances the activity of CD8+T cells in the tumor niche. Then, we found that DHA was bound to cellular YAP1 in HCC cells. YAP1 knockdown inhibited GLUT1-mediated aerobic glycolysis, whereas YAP1 overexpression promoted GLUT1-mediated aerobic glycolysis in HCC cells. Notably, liver-specific Yap1 knockout by AAV8-TBG-Cre suppressed HIF-1α and GLUT1 expression in tumors but not para-tumors in DEN/TCPOBOP-induced HCC mice. Even more crucial is that YAP1 forms a positive feedback loop with GLUT1-mediated aerobic glycolysis, which is associated with HIF-1α in HCC cells. Finally, DHA reduced GLUT1-aerobic glycolysis in HCC cells through YAP1 and prevented the binding of YAP1 and HIF-1α. Collectively, our study revealed the mechanism of DHA inhibiting glycolysis in HCC cells from a perspective of a positive feedback loop involving YAP1 and GLUT1 mediated-aerobic glycolysis and provided a feasible therapeutic strategy for targeting enhanced aerobic glycolysis in HCC.

Enhanced Sampling Molecular Dynamics Simulations Reveal Transport Mechanism of Glycoconjugate Drugs through GLUT1.

Glucose transporters GLUT1 belong to the major facilitator superfamily and are essential to human glucose uptake. The overexpression of GLUT1 in tumor cells designates it as a pivotal target for glycoconjugate anticancer drugs. However, the interaction mechanism of glycoconjugate drugs with GLUT1 remains largely unknown. Here, we employed all-atom molecular dynamics simulations, coupled to steered and umbrella sampling techniques, to examine the thermodynamics governing the transport of glucose and two glycoconjugate drugs (i.e., 6-D-glucose-conjugated methane sulfonate and 6-D-glucose chlorambucil) by GLUT1. We characterized the specific interactions between GLUT1 and substrates at different transport stages, including substrate recognition, transport, and releasing, and identified the key residues involved in these procedures. Importantly, our results described, for the first time, the free energy profiles of GLUT1-transporting glycoconjugate drugs, and demonstrated that H160 and W388 served as important gates to regulate their transport via GLUT1. These findings provide novel atomic-scale insights for understanding the transport mechanism of GLUT1, facilitating the discovery and rational design of GLUT1-targeted anticancer drugs.