Temporal and regional expression changes and co-staining patterns of metabolic and stemness-related markers during glioblastoma progression

Glioblastomas (GBMs) are characterized by high heterogeneity, involving diverse cell types, including those with stem-like features contributing to GBM's malignancy. Moreover, metabolic alterations promote growth and therapeutic resistance of GBM. Depending on the metabolic state, antimetabolic treatments could be an effective strategy. Against this background, we investigated temporal and regional expression changes and co-staining patterns of selected metabolic markers [pyruvate kinase muscle isozyme 1/2 (PKM1/2), glucose transporter 1 (GLUT1), monocarboxylate transporter 1/4 (MCT1/4)] in a rodent model and patient-derived samples of GBM. To understand the cellular sources of marker expression, we also examined the connection of metabolic markers to markers related to stemness [Nestin, Krüppel-like factor 4 (KLF4)] in a regional and temporal context. Rat tumour biopsies revealed a temporally increasing expression of GLUT1, higher expression of MCT1/4, Nestin and KLF4, and lower expression of PKM1 compared to the contralateral hemisphere. Patient-derived tumours showed a higher expression of PKM2 and Nestin in the tumour centre vs. edge. Whereas rare co-staining of GLUT1/Nestin was found in tumour biopsies, PKM1/2 and MCT1/4 showed a more distinct co-staining with Nestin in rats and humans. KLF4 was mainly co-stained with GLUT1, MCT1 and PKM1/2 in rat and human tumours. All metabolic markers yielded individual co-staining patterns among themselves. Co-staining mainly occurred later in tumour progression and was more pronounced in tumour centres. Also, positive correlations were found amongst markers that showed co-staining. Our results highlight a link between metabolic alterations and stemness in GBM progression, with complex distinctions depending on studied markers, time points and regions.

Cannabidiol Exposure During Rat Pregnancy Leads to Labyrinth-Specific Vascular Defects in the Placenta and Reduced Fetal Growth

Introduction: Cannabis use is increasing among pregnant people, and cannabidiol (CBD), a constituent of cannabis, is often perceived as "natural" and "safe" as it is non-intoxicating. In utero, cannabis exposure is associated with negative health outcomes, including fetal growth restriction (FGR). The placenta supplies oxygen and nutrients to the fetus, and alterations in placental development can lead to FGR. While there has been some investigation into the effects of Δ9-THC, there has been limited investigation into the impacts of in utero gestational CBD exposure on the placenta. Methods: This study used histological and transcriptomic analysis of embryonic day (E)19.5 rat placentas from vehicle and CBD (3 mg/kg intraperitoneal injection) exposed pregnancies (E6.5-18.5). Results: The study revealed that pups from CBD-exposed pregnancies were 10% smaller, with the placentae displaying a decreased fetal blood space perimeter-to-area ratio. The transcriptomic analysis supported compromised angiogenesis and blood vessel formation with downregulated biological processes, including tube morphogenesis, angiogenesis, blood vessel morphogenesis, blood vessel development and vasculature development. Further, the CBD-exposed placentas displayed changed expression of glucose transporters (decreased GLUT1 and GR expression and increased GLUT3 expression). Transcriptomic analysis further revealed upregulated biological processes associated with metabolism. Finally, histological and transcriptomic analysis revealed altered cell populations within the placenta, specifically to syncytiotrophoblast layer II and endothelial cells. Conclusion: Together these results suggest that the structural changes in CDB-exposed placentae, including the altered expression of nutrient transporters and the changes to the placental fetal vasculature, may underlie the reduced fetal growth.

Xanthatin induce DDP-resistance lung cancer cells apoptosis through regulation of GLUT1 mediated ROS accumulation

Chemoresistance to cisplatin (DDP) therapy is a major obstacle that needs to be overcome in treating lung cancer patients. Xanthatin has been reported to exhibit an antitumor effect on various cancers, but the function of xanthatin in DDP-resistance lung cancer remains unclear. The study aimed to explore the effect and mechanisms of xanthatin on proliferation, apoptosis, and migration in DDP-resistance lung cancer cells. In the present study, xanthatin suppresses the expression of glucose transporter 1 (GLUT1), attenuates the pentose phosphate pathway (PPP), and causes ROS accumulation and apoptosis, thereby mitigating the antioxidative capacity in DDP-resistance cells. Previous studies have shown that GLUT1 is associated with resistance to platinum drugs. We found that GLUT1 was significantly increased in the DDP-resistant lung cancer cell line compared to the parental cell line, and xanthatin significantly downregulated GLUT1 expression in DDP-resistant lung cancer cells. Notably, overexpression of GLUT1 significantly reduced the production of ROS and increased cellular NADPH/NADP+ and GSH/GSSG ratios. Thus, these results suggest that xanthatin induces DDP-resistance lung cancer cells apoptosis through regulation of GLUT1-mediated ROS accumulation. These findings might provide a possible strategy for the clinical treatment of DDP-resistant lung cancer.

Prognostic impact of the combination of HIF‑1α and GLUT1 in patients with oesophageal squamous cell carcinoma

Oesophageal squamous cell carcinoma (ESCC) is a common type of carcinoma. Hypoxia is associated with chemo- and radio-resistance, which may lead to a poor prognosis. Hypoxia-inducible factor-1α (HIF-1α) is the main transcriptional regulator of the cellular response to low oxygen levels. Moreover, it can trigger the expression of critical genes, including glucose transporter protein type 1 (GLUT1). The aim of the present study was to evaluate the roles of HIF-1α and GLUT1 in ESCC and their usefulness as prognostic markers. HIF-1α and GLUT1 were measured in four ESCC cell lines, namely Eca109, KYSE150, TE-1 and TE-10, by western blotting following culture under normoxic and hypoxic conditions. In addition, xenograft tumors were established in mice using normoxic and hypoxic Eca109 cells and the chemosensitivity of the xenografts to 5-fluorouracil (5-FU) was evaluated. Furthermore, HIF-1α and GLUT1 were analysed by immunochemistry in the tumor tissues of patients with ESCC and the associations of their expression levels with clinicopathological parameters were investigated. The results revealed that HIF-1α and GLUT1 protein expression was weak in all four cell lines under a normoxic atmosphere but increased following culture in a hypoxic environment. In vivo, 5-FU inhibited tumor growth more strongly in normoxic Eca109 ×enografts than hypoxic Eca109 ×enografts. Higher levels of apoptosis were also detected in the normoxic Eca109 ×enografts via western blotting and TUNEL analysis. In patients with ESCC, HIF-1α expression was associated with advanced ESCC while GLUT1 expression was associated with the sex of the patients. Multivariate analysis demonstrated that HIF-1α and GLUT1 were negatively associated with progression-free survival (PFS) and overall survival (OS). Additionally, a combination of HIF-1α and GLUT1 expression was a predictor of RFS and OS in patients with ESCC without lymph node metastasis but not those with lymph node metastasis. The study demonstrated that HIF-1α and GLUT1 were strongly expressed in vitro and in xenograft models when cells were exposed to hypoxia. The simultaneous high expression of HIF-1α and GLUT1 was associated with poorer survival, and may play an important role in ESCC chemoresistance and the prognosis of ESCC.

Self-Assembled Carrier-Free Nanodrugs for Starvation Therapy-Amplified Photodynamic Therapy of Cancer

Traditional starvation treatment strategies, which involve glucose oxidase and drug-induced thrombi, often suffer from aggravated tumor hypoxia and have failed to improve antitumor efficacy in combination with oxygen-dependent photodynamic therapy (PDT). Herein, glucose transporter 1 inhibitor genistein (Gen) and photosensitizer chlorin e6 (Ce6) are integrated to construct carrier-free self-assembled nanoparticles defined as GC NPs, for starvation therapy-amplified PDT of tumor. GC NPs with regular morphology and stability are screened out by component adjustment, while the function of each component is preserved. On the one hand, Gen released from GC NPs can cut off tumor glucose uptake by inhibiting the glucose transporter 1 to restrict tumor growth, achieving starvation therapy. On the other hand, they are able to decrease the amount of oxygen consumed by tumor respiration and amplify the therapeutic effect of PDT. In vitro and in vivo experiments verify the excellent synergistic antitumor therapeutic efficacy of GC NPs without any apparent toxicity. Moreover, fluorescence and photoacoustic imaging provide guidance for in vivo PDT, demonstrating the excellent tumor enrichment efficiency of GC NPs. It is believed that this starvation therapy-amplified PDT strategy by carrier-free self-assembled GC NPs holds promising clinical prospects.

Combination of Circulating Cell-Free DNA and Positron Emission Tomography to Distinguish Non-Small Cell Lung Cancer from Tuberculosis

OBJECTIVE

Non-small cell lung cancer (NSCLC) holds high metabolic tumor burden and circulating cell-free DNA (cfDNA) levels, and the relationship between metabolic tumor burden and cfDNA in NSCLC and the underlying mechanism of their interaction therein remain poorly characterized. Our aim was to evaluate the clinical value of cfDNA and metabolic tumor burden by positron emission tomography-computed tomography (PET/CT) for NSCLC differential diagnosis from tuberculosis in patients with solitary pulmonary nodules.

METHODS

Metabolic tumor burden values in humans (subjects with NSCLC, subjects with tuberculosis, and healthy control subjects) and relevant mouse models were detected by preoperative 18F-fluorodeoxyglucose PET (18F-FDG PET/CT) and [3H]-2-deoxy-DG uptake, respectively. The cfDNA levels were detected by quantifying serum cfDNA fragments from the ALU (115 bp) gene using reverse transcription-polymerase chain reaction. RNA sequence was performed to determine the underlying target genes and knocked down or inhibited the target genes in vivo and in vitro to determine the mechanism therein.

RESULTS

Metabolic tumor burden correlated with serum cfDNA levels in NSCLC subjects but not in tuberculosis subjects or healthy controls. Mouse models showed a similar phenomenon. In addition, the RNA sequence showed that glucose transporter 1 (GLU1), factor-related apoptosis ligand (FasL), caspase 8, and caspase 3 were significantly increased in NSCLC mouse tumors compared with those in tuberculosis mouse masses. Inhibiting the metabolic tumor burden by blocking or knocking down GLU1 markedly reduced the expression of FasL, the phosphorylation of caspase 8/caspase 3, and serum cfDNA levels/apoptosis percentage in vivo and in vitro. Furthermore, the use of a combination of cfDNA and metabolic tumor burden allowed better ability to distinguish NSCLC subjects from those with tuberculosis or healthy controls than either method used alone.

CONCLUSION

Metabolic tumor burden promotes the formation of circulating cfDNA through GLU1-mediated apoptosis in NSCLC, and the combination of cfDNA and metabolic tumor burden could be valuable for distinguishing NSCLC from tuberculosis.

GLUT1 and PKM2 may be useful prognostic predictors in patients with non‑small cell lung cancer following curative R0 resection

Lung cancer has a poor prognosis despite recent progresses being made regarding its treatment. In addition, there is a paucity of reliable and independent prognostic predictors for non-small cell lung cancer (NSCLC) following curative resection. Glycolysis is associated with the malignancy and proliferation of cancer cells. Glucose transporter 1 (GLUT1) promotes glucose uptake, whereas pyruvate kinase M2 (PKM2) promotes anaerobic glycolysis. The present study aimed to evaluate the relationship between the expression of GLUT1 and PKM2 and the clinicopathological features of patients with NSCLC, and to identify a reliable prognostic factor for NSCLC following curative resection. Patients with NSCLC who underwent curative surgery were retrospectively enrolled to the present study. GLUT1 and PKM2 expression was assessed using immunohistochemistry. Subsequently, the association between the clinicopathological features of patients with NSCLC and the expression of GLUT1 and PKM2 was assessed. Of the 445 patients with NSCLC included in the present study, 65 (15%) were positive for both GLUT1 and PKM2 expression (G+/P+ group). GLUT1 and PKM2 positivity was significantly associated with sex, absence of adenocarcinoma, lymphatic invasion and pleural invasion. Furthermore, patients with NSCLC in the G+/P+ group presented significantly poorer survival rates than those expressing other markers. G+/P+ expression was significantly associated with poor disease-free survival. In conclusion, the findings of the present study indicated that the combination of GLUT1 and PKM2 may be considered a reliable prognostic factor for patients with NSCLC following curative resection, especially in patients with stage I NSCLC.

Urinary Catheterization Induces Delirium-Like Behavior Through Glucose Metabolism Impairment in Mice

BACKGROUND

Delirium, an acute confusion status, is associated with adverse effects, including the development of Alzheimer's disease. However, the etiology and underlying mechanisms of delirium remain largely to be determined. Many patients have urinary catheterization (UC), and UC is associated with delirium. However, the cause effects of UC-associated delirium and the underlying mechanisms remain largely unknown. We, therefore, established an animal model of UC, without urinary tract infection, in mice and determined whether UC could induce delirium-like behavior in the mice and the underlying mechanism of these effects.

METHODS

Adult female mice (16 weeks old) had UC placement under brief isoflurane anesthesia. The delirium-like behavior was determined using our established mice model at 3, 6, 9, and 24 hours after UC placement. We measured the amounts of glucose in both blood and brain interstitial fluid, adenosine triphosphate (ATP) concentration in the cortex, and glucose transporter 1 in the cortex of mice using western blot, immunohistochemistry imaging, reverse transcriptase-polymerase chain reaction (RT-PCR), and fluorescence at 6 hours after the UC placement. Finally, we used vascular endothelial growth factor (VEGF) in the interaction studies.

RESULTS

We found that UC induced delirium-like behavior in mice at 3, 6, 9, but not 24 hours after the UC placement. UC decreased glucose amounts in brain interstitial fluid (86.38% ± 4.99% vs 100% ± 6.26%, P = .003), but not blood of mice and reduced ATP amounts (84.49% ± 8.85% vs 100% ± 10.64%, P = .031) in the cortex of mice. Finally, UC reduced both protein amount (85.49% ± 6.83% vs 100% ± 11.93%, P = .040) and messenger ribonucleic acid (mRNA) expression (41.95% ± 6.48% vs 100% ± 19.80%, P = .017) of glucose transporter 1 in the cortex of mice. VEGF attenuated these UC-induced changes.

CONCLUSIONS

These data demonstrated that UC decreased brain glucose and energy amounts via impairing the glucose transport from blood to brain, leading to delirium-like behavior in mice. These findings will promote more research to identify the etiologies and underlying mechanisms of delirium.

DNMT3a promotes osteoblast differentiation and alleviates osteoporosis via the PPARγ/SCD1/GLUT1 axis

Background: This study was designed to elucidate the role of DNMT3a and PPARγ functions in postmenopausal osteoporosis. Materials & methods: Mice were ovariectomized to establish an in vivo osteoporosis model and MC3T3-E1-14 osteoblasts were induced to differentiate. Gain- or loss-of-function approaches were used to manipulate the expression of PPARγ, DNMT3a and SCD1, followed by an evaluation of their role in postmenopausal osteoporosis both in vivo and in vitro. Results: DNMT3a induced methylation of the PPARγ promoter region, consequently stimulating osteoblast differentiation. PPARγ elevated SCD1, which decreased GLUT1 and inhibited osteoblast differentiation. Inhibition of PPARγ reduced SCD1 while increasing GLUT1 expression, thus alleviating postmenopausal osteoporosis in mice. Conclusion: DNMT3a promotes osteoblast differentiation and prevents postmenopausal osteoporosis by regulating the PPARγ/SCD1/GLUT1 axis.

Concentration of hypoxia-inducible factor-1, glucose transporter 1 and vascular endothelial growth factor in tissue samples and serum in patients with primary laryngeal carcinoma

BACKGROUND

Markers of tumorigenesis are essential factors which may play a major role in the early detection of head and neck carcinoma.

AIMS/OBJECTIVES

To assess concentration of HIF-1, GLUT1 and VEGF in tissue samples and blood serum and its correlation to the tumour size, nodal disease, pathologic differentiation and patients' data.

MATERIAL AND METHODS

Fifty-two patients diagnosed with laryngeal carcinoma stage I-IV in which concentration of HIF-1, GLUT1 and VEGF was assessed in tissue samples and blood serum using immunoassay method.

RESULTS

HIF-1α, GLUT1, VEGF concentration was significantly higher in cancer tissue samples than in normal tissue (p < .001) and benign laryngeal lesions. Serum levels of the factors were significantly lower in the control group. Statistically significant difference regarding tumour size was found between T2 and T4 stages in HIF-1α concentration in cancer samples and serum.

CONCLUSIONS

The results show that high concentration of HIF-1α, GLUT1 and VEGF might be suggestive of carcinogenic process when diagnosing patients with laryngeal lesions and could promote early detection of malignancy.

SIGNIFICANCE

The results of this study show importance of biochemical assessment in malignant tumours which may affect clinical decisions.

Fungal sensing enhances neutrophil metabolic fitness by regulating antifungal Glut1 activity

Combating fungal pathogens poses metabolic challenges for neutrophils, key innate cells in anti-Candida albicans immunity, yet how host-pathogen interactions cause remodeling of the neutrophil metabolism is unclear. We show that neutrophils mediate renal immunity to disseminated candidiasis by upregulating glucose uptake via selective expression of glucose transporter 1 (Glut1). Mechanistically, dectin-1-mediated recognition of β-glucan leads to activation of PKCδ, which triggers phosphorylation, localization, and early glucose transport by a pool of pre-formed Glut1 in neutrophils. These events are followed by increased Glut1 gene transcription, leading to more sustained Glut1 accumulation, which is also dependent on the β-glucan/dectin-1/CARD9 axis. Card9-deficient neutrophils show diminished glucose incorporation in candidiasis. Neutrophil-specific Glut1-ablated mice exhibit increased mortality in candidiasis caused by compromised neutrophil phagocytosis, reactive oxygen species (ROS), and neutrophil extracellular trap (NET) formation. In human neutrophils, β-glucan triggers metabolic remodeling and enhances candidacidal function. Our data show that the host-pathogen interface increases glycolytic activity in neutrophils by regulating Glut1 expression, localization, and function.

The effect of lactate dehydrogenase-A inhibition on intracellular nucleotides and mitochondrial respiration in pancreatic cancer cells

Pancreatic cancer (PC) is one of the most lethal malignancies. PC is characterized by a high expression of the glucose transporter GLUT-1 and of lactate dehydrogenase A (LDH-A). The novel LDH-A inhibitor NHI-Glc-2 was designed for a better uptake via GLUT-1 and was shown to be cytotoxic against the PC cell line PANC-1. Using RP-HPLC we investigated its effect on adenine nucleotides and NADH/NAD+, while the Seahorse analyzer was used to determine its effect on glycolysis and mitochondrial function. A 24 hour exposure to 10 µM NHI-Glc-2 (around the IC50) decreased the ATP concentration by about 10%, but at 25 µM this decrease was 38%, while NAD+ decreased by 26%, associated with a 35% decrease in the NADH/NAD+ ratio. A 10 µM NHI-Glc-2 decreased extracellular acidification and oxygen consumption (about 75%), as well as the mitochondrial respiration parameters by 50%. In conclusion, LDH-A inhibition markedly affected the energy supply of PANC-1 cells. The respiration data indicated a dependency of the cells on glycolysis and fatty acid oxidation.Supplemental data for this article is available online at https://doi.org/10.1080/15257770.2022.2031215 .

Human papillomavirus16 E6 but not E7 upregulates GLUT1 expression in lung cancer cells by upregulating thioredoxin expression

Background and objective: E6 and E7 proteins in human papillomavirus (HPV) 16 are major oncogenes in several types of tumors, including lung cancer. Previous studies have demonstrated that both E6 and E7 oncoproteins can upregulate GLUT1 protein and mRNA expression levels in lung cancer cells. Thus, the present study aimed to investigate the main differences in the molecular mechanisms of GLUT1 expression regulated by E6 and E7. Methods: The double directional genetic manipulation and immunofluorescence were performed to explore the molecular mechanism of E6 or E7 upregulating the expression of GLUT1 in H1299 and A549 cell lines. Results: The overexpression of E6 in well-established lung cancer cell lines upregulated thioredoxin (Trx) protein expression. Notably, plasmid transfection or small interfering RNA transfection with E7 had no regulatory effect on Trx expression. As an important disulfide reductase of the intracellular antioxidant system, Trx plays important role in maintaining oxidative stress balance and protecting cells from oxidative damage. The overexpression of Trx increased the activation of NF-κB by upregulating p65 expression and promoting p65 nuclear translocation, and further upregulated GLUT1 protein and mRNA expression levels. The results of the present study demonstrated that E6, but not E7, upregulated GLUT1 expression in lung cancer cells by activating NF-κB due to the participation of Trx. Conclusion: These results suggest that Trx plays an important role in the pathogenesis of HPV-associated lung cancer, and propose a novel therapeutic target for HPV-associated lung cancer.

EgGLUT1 Is Crucial for the Viability of Echinococcus granulosus sensu stricto Metacestode: A New Therapeutic Target?

Cystic echinococcosis (CE) is a zoonotic parasitic disease caused by infection with the larvae of Echinococcus granulosus sensu lato (s.l.) cluster. It is urgent to identify novel drug targets and develop new drug candidates against CE. Glucose transporter 1 (GLUT1) is mainly responsible for the transmembrane transport of glucose to maintain its constant cellular availability and is a recent research hotspot as a drug target in various diseases. However, the role of GLUT1 in E. granulosus s.l. (EgGLUT1) was unknown. In this study, we cloned a conserved GLUT1 homology gene (named EgGLUT1-ss) from E. granulosus sensu stricto (s.s.) and found EgGLUT1-ss was crucial for glucose uptake and viability by the protoscoleces of E. granulosus s.s. WZB117, a GLUT1 inhibitor, inhibited glucose uptake by E. granulosus s.s. and the viability of the metacestode in vitro. In addition, WZB117 showed significant therapeutic activity in E. granulosus s.s.-infected mice: a 10 mg/kg dose of WZB117 significantly reduced the number and weight of parasite cysts (P < 0.05) as efficiently as the reference drug, albendazole. Our results demonstrate that EgGLUT1-ss is crucial for glucose uptake by the protoscoleces of E. granulosus s.s., and its inhibitor WZB117 has a therapeutic effect on CE.

Clinical Significance of 18F-fluorodeoxyglucose and Glucose Transporter 1 mRNA in Clear Cell Renal Cell Carcinoma

BACKGROUND/AIM

¹⁸F-fluorodeoxyglucose (FDG) uptake measurement on positron emission tomography/computed tomography (PET/CT) is difficult in renal tumors because of the nearby renal parenchyma and urinary tract, which excrete FDG. We carefully examined the maximum standardized uptake value (SUV_max) on FDG-PET/CT and investigated the relationship between major glucose transporters in the kidney and clear cell renal cell carcinoma (ccRCC) progression.

PATIENTS AND METHODS

Forty-five patients with ccRCC underwent FDG-PET/CT for staging and nephrectomy. Glucose transporter mRNA expression was examined in the removed kidney.

RESULTS

SUV_max was increased in high-stage and high-grade tumors. Glucose transporter 1 (GLUT1) mRNA expression was higher in tumor tissues, in contrast to other glucose transporters. SUV_max was not correlated with GLUT1 mRNA expression. Kaplan-Meier analysis showed reduced overall and recurrence-free survival in the high SUVmax group.

CONCLUSION

Primary ccRCC lesions show a high SUV_max and GLUT1 mRNA over-expression. SUV_max increases with tumor upstaging and upgrading.

Clinical Utility and Limitation of Diagnostic Ability for Different Degrees of Dysplasia of Intraductal Papillary Mucinous Neoplasms of the Pancreas Using 18F-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography

Simple Summary

Elucidating risk factors for different degrees of dysplasia of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas is important in determining strategies for management. In this study, we searched for risk factors for different degrees of dysplasia of IPMNs. Our study indicated that there were no useful factors that significantly differentiated low-grade dysplasia and high-grade dysplasia; however, ¹⁸F-fluorodeoxyglucose–positron emission tomography/computed tomography is useful for differentiating between non-invasive and invasive IPMNs. Our results offer critical information that may determine surgical treatment strategies.

Abstract

The diagnostic value of ¹⁸F-fluorodeoxyglucose (FDG) uptake in the management of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas remains unclear. This study aimed to assess the role of FDG uptake in the diagnosis of different degrees of dysplasia of IPMNs. We retrospectively analyzed the following three points in 84 patients with IPMNs: (1) risk factors to predict high-grade dysplasia (HGD) and invasive carcinoma (INV); (2) the relationship between FDG uptake and glucose transporter 1 (GLUT-1) expression; and (3) the relationship between FDG uptake and the presence of mural nodules. The histopathological diagnosis was low-grade dysplasia (LGD) in 43 patients, HGD in 16, and INV in 25. The maximum standardized uptake value (SUV-max) was significantly higher in INV than in LGD/HGD (p < 0.0001, p = 0.0136). The sensitivity and specificity to discriminate INV from LGD/HGD were 80.0% and 86.2%, respectively, using the receiver operator characteristic curve, when the optimal cutoff score of SUV-max was set at 4.03. Those values were not different between HGD and LGD. More than half of HGD patients had low GLUT-1 expression. Taken together, FDG-PET/CT is useful in distinguishing between non-invasive and invasive IPMN. Our results offer critical information that may determine surgical treatment strategies.

18F-FDG PET/CT metabolic parameters correlate with EIF2S2 expression status in colorectal cancer

Background: We sought to investigate whether the expression of the gene EIF2S2 is related to ¹⁸F-FDG PET/CT metabolic parameters in patients with colorectal cancer (CRC).

Materials and methods: The expression of EIF2S2 in CRC and its relationship with clinicopathological features were obtained through the ONCOMINE, UALCAN and GEPIA databases. EIF2S2 and GLUT1 expression were examined by immunohistochemistry in 42 CRC patients undergoing preoperative PET-CT examination. Spearman correlation analysis was used to assess the relationship between EIF2S2 and GLUT1 levels and clinical parameters. Correlation analysis between EIF2S2 and Reactome-Glycolysis signatures was performed using GEPIA2. We describe the effect of EIF2S2 knockdown on lactate production and the mRNA levels of glycolysis-related genes in human colon cancer SW480 cells.

Results: Immunohistochemistry revealed an upregulation of EIF2S2 protein expression in tumor tissues of colorectal cancer patients, which is consistent with the significant upregulation of EIF2S2 transcript levels in the database. These colorectal cancer patients included 24 cases of colon cancer and 18 cases of rectal cancer, ranging in age from 31 to 78 years. The transcription was significantly related to histological subtypes and TP53 mutations (P <0.05). The value of SUVmax in CRC significantly correlated with the expression of EIF2S2 (rho = 0.462, P <0.01). Although SUVmax and SUVmean was not correlate with the expression of GLUT1 (P <0.05), a significant correlation was observed between the expression of GLUT1 and the volumetric PET parameters, such as MTV and TLG (P < 0.01). GLUT1 expression in CRC was positively correlated with EIF2S2 status (rho = 0.470, P <0.01). In SW480 cells, RNAi-mediated depletion of EIF2S2 inhibited lactic acid production (P <0.05) and SLC2A1, SLC2A3, SLC2A10, HK2, PKM2, LDHA mRNA level (P <0.01).

Conclusions: Primary CRC FDG uptake is strongly associated with the overexpression of EIF2S2, and EIF2S2 may promote glycolysis in CRC by mediating GLUT1.

Physiologic Mechanical Stress Directly Induces Bone Formation by Activating Glucose Transporter 1 (Glut 1) in Osteoblasts, Inducing Signaling via NAD+-Dependent Deacetylase (Sirtuin 1) and Runt-Related Transcription Factor 2 (Runx2)

Mechanical stress is an important factor affecting bone tissue homeostasis. We focused on the interactions among mechanical stress, glucose uptake via glucose transporter 1 (Glut1), and the cellular energy sensor sirtuin 1 (SIRT1) in osteoblast energy metabolism, since it has been recognized that SIRT1, an NAD+-dependent deacetylase, may function as a master regulator of the mechanical stress response as well as of cellular energy metabolism (glucose metabolism). In addition, it has already been demonstrated that SIRT1 regulates the activity of the osteogenic transcription factor runt-related transcription factor 2 (Runx2). The effects of mechanical loading on cellular activities and the expressions of Glut1, SIRT1, and Runx2 were evaluated in osteoblasts and chondrocytes in a 3D cell-collagen sponge construct. Compressive mechanical loading increased osteoblast activity. Mechanical loading also significantly increased the expression of Glut1, significantly decreased the expression of SIRT1, and significantly increased the expression of Runx2 in osteoblasts in comparison with non-loaded osteoblasts. Incubation with a Glut1 inhibitor blocked mechanical stress-induced changes in SIRT1 and Runx2 in osteoblasts. In contrast with osteoblasts, the expressions of Glut1, SIRT1, and Runx2 in chondrocytes were not affected by loading. Our present study indicated that mechanical stress induced the upregulation of Glut1 following the downregulation of SIRT1 and the upregulation of Runx2 in osteoblasts but not in chondrocytes. Since SIRT1 is known to negatively regulate Runx2 activity, a mechanical stress-induced downregulation of SIRT1 may lead to the upregulation of Runx2, resulting in osteoblast differentiation. Incubation with a Glut1 inhibitor the blocked mechanical stress-induced downregulation of SIRT1 following the upregulation of Runx2, suggesting that Glut1 is necessary to mediate the responses of SIRT1 and Runx2 to mechanical loading in osteoblasts.

HIF1 may promote glycolysis in psoriasis vulgaris via upregulation of CD147 and GLUT1

OBJECTIVES

To analyze the expressions and distributions of hypoxia-inducible factor-1α (HIF-1α), CD147, and glucose transporter 1 (GLUT1) in epidermis from psoriasis vulgaris and normal people, and to explore the associations among these proteins and their roles in hypoxic HaCaT cell line.

METHODS

The expression levels of HIF-1α, CD147, and GLUT1 were determined by immunohistochemistry staining in skin biopsies from 48 psoriasis vularis patients and 33 healthy subjects. Cobalt chloride (CoCl2) was added into the culture media of HaCaT cells to mimic hypoxia while RNA interference and transfection technologies were used to explore the association among these proteins by quantitative real-time polymerase chain reaction and Western blotting. Glycolytic capacity was detected by ATP and lactate measurements.

RESULTS

HIF-1α, CD147, and GLUT1 were highly expressed and the glycolytic capacity was increased in lesions of psoriasis vulgaris; HIF-1α upregulated the expression of CD147 and GLUT1, increased the lactate production and decreased the ATP level in CoCl2-treated HaCaT cells, while CD147 and GLUT1 directly or indirectly bound to each other.

CONCLUSIONS

Glycolytic capacity increases in the injured keratinocytes of psoriasis vulgaris, suggesting that HIF-1α, CD147, and GLUT1 are associated with glycolysis, which can be considered as the promising targets for psoriasis therapy.

Cancer Cells' Metabolism Dynamics in Renal Cell Carcinoma Patients' Outcome: Influence of GLUT-1-Related hsa-miR-144 and hsa-miR-186

Simple Summary

Renal cell carcinoma (RCC) is a metabolic associated cancer and the most common and lethal neoplasia in the adult kidney. This study aimed to understand the potential role of hsa-miR-144-5p and hsa-miR-186-3p (which target Glucose Transporter 1—GLUT-1) in clear cell RCC (ccRCC) glycolysis status, as well as their potential as biomarkers. A decrease of intracellular levels of these miRNAs and increase of their excretion was associated with an increase of GLUT-1’s levels and glycolysis’ markers. RCC patients presented higher plasmatic levels of hsa-miR-186-3p than healthy individuals and hsa-miR144-5p’s higher levels were associated with early clinical stages of RCC. Additionally, patients with low plasmatic levels of hsa-miR-144-5p and high plasmatic levels of hsa-miR-186-3p (high-risk group) showed a worse overall survival. Overall, these results indicate that circulating hsa-miR-144-5p and hsa-miR-186-3p may be potential biomarkers of ccRCC prognosis.

Abstract

The cancer cells’ metabolism is altered due to deregulation of key proteins, including glucose transporter 1 (GLUT-1), whose mRNA levels are influenced by microRNAs (miRNAs). Renal cell carcinoma (RCC) is the most common and lethal neoplasia in the adult kidney, mostly due to the lack of accurate diagnosis and follow-up biomarkers. Being a metabolic associated cancer, this study aimed to understand the hsa-miR-144-5p and hsa-miR-186-3p’s potential as biomarkers of clear cell RCC (ccRCC), establishing their role in its glycolysis status. Using three ccRCC lines, the intra- and extracellular levels of both miRNAs, GLUT-1’s mRNA expression and protein levels were assessed. Glucose consumption and lactate production were evaluated as glycolysis markers. A decrease of intracellular levels of these miRNAs and increase of their excretion was observed, associated with an increase of GLUT-1’s levels and glycolysis’ markers. Through a liquid biopsy approach, we found that RCC patients present higher plasmatic levels of hsa-miR-186-3p than healthy individuals. The Hsa-miR144-5p’s higher levels were associated with early clinical stages. When patients were stratified according to miRNAs plasmatic levels, low plasmatic levels of hsa-miR-144-5p and high plasmatic levels of hsa-miR-186-3p (high-risk group) showed the worst overall survival. Thus, circulating levels of these miRNAs may be potential biomarkers of ccRCC prognosis.

Purification of Gekko Small Peptide Fraction and Its Effect of Inducing Apoptosis of EC 9706 Esophageal Cancer Cells by Inhibiting PI3K/Akt/GLUT1 Signaling Pathway

This study aimed to isolate and purify a cytotoxic extraction from Gekko japonicus, identify its components and determine its cytotoxic activity in vitro. We isolated and identified the most potent cytotoxic Gekko small peptide LH-20-15. The identification and analysis of peptide sequences of LH-20-15 were performed by de novo peptide sequencing, and two new peptides were found. LH-20-15 significantly inhibited the proliferation of human esophageal squamous carcinoma EC 9706 cells in a dose-dependent manner. Furthermore, LH-20-15 induced apoptosis in esophageal cancer cells by activating the mitochondrial apoptotic pathway. Further research showed that LH-20-15 inhibited the PI3 K/Akt/GLUT1 signaling pathway. In conclusion, LH-20-15 from Gekko japonicus is a peptide mixture and may inhibit EC 9706 cell proliferation and induce apoptosis by activating the mitochondrial apoptotic pathway. It also regulates glucose metabolism by targeting the PI3 K/Akt/GLUT1 signaling pathway. These small peptides could be new sources of natural cytotoxic ingredients against esophageal cancer with potential drug values.

MicroRNA-140-5p is Downregulated in Osteosarcoma and Overexpression of MicroRNA-140-5p Inhibits Cancer Cell Proliferation by Downregulating GLUT-1

Background

MicroRNA-140-5p plays pivotal role in different types of human malignancies, while its involvement in osteosarcoma is unknown.

Objective

Our study aimed to investigate the functionality of microRNA-140-5p in osteosarcoma.

Methods

Plasma levels of microRNA-140-5p and glucose transporter 1 (GLUT-1) in both osteosarcoma and healthy controls were measured by qRT-PCR and ELISA, respectively. Correlation between plasma levels of microRNA-140-5p and GLUT-1 was analyzed by Pearson correlation coefficient. Correlation between plasma levels of microRNA-140-5p and clinical data of patients with osteosarcoma was analyzed by Chi-square test. MicroRNA-140-5p mimic and GLUT-1 expression vector were transfected into cells of human osteosarcoma cell lines, and the effects on microRNA-140-5p expression, GLUT-1 expression and cell proliferation were analyzed by qRT-PCR, Western-blot and CCK-8 assay, respectively.

Results

Plasma levels of microRNA-140-5p were significantly lower and plasma levels of GLUT-1 were significantly higher in osteosarcoma patients than that in healthy controls. Levels of plasma microRNA-140-5p and GLUT-1 were reversely correlated in osteosarcoma patients. Plasma levels of microRNA-140-5p were correlated with tumor size but not with other clinical data of patients. MicroRNA-140-5p mimic significantly inhibited cancer cell proliferation, while GLUT-1 overexpression significantly promoted cancer cell proliferation. MicroRNA-140-5p mimic significantly downregulated GLUT-1 expression.

Conclusion

GLUT-1 overexpression showed no significant effect on microRNA-140-5p expression but attenuated the inhibitory effects of microRNA-140-5p mimic on cell proliferation. We therefore conclude that microRNA-140-5p is downregulated in osteosarcoma and overexpression of microRNA-140-5p may inhibit cancer cell proliferation by downregulating GLUT-1.

MUC16 promotes EOC proliferation by regulating GLUT1 expression

As a common malignancy in females with a higher incidence rate, epithelial ovarian cancer (EOC) is a heterogeneous disease with complexity and diversity in histology and therapeutic response. Although great progress has been made in diagnosis and therapeutic strategies, novel therapeutic strategies are required to improve survival. Although the promoting effect of mucin 16 (MUC16) on tumour progression has been reported, the potential mechanisms remain unclear. In our study, we reported that overexpression of MUC16 was significantly related to cell proliferation and disease progression in EOC. Results from clinical specimen analysis and cell experiment support this conclusion. Patients with a high MUC16 expression usually had a worse prognosis that those with a low expression. Cell proliferation ability was significantly decreased in EOC cell lines when the knockdown of MUC16. Further study shows that the function of MUC16 in cell proliferation is based on the regulation of glucose transporter 1 (GLUT1) expression. MUC16 can control glucose uptake by regulating GLUT1 in EOC cells, thereby promoting glycogen synthesis, so that tumour cells produce more energy for proliferation. This conclusion is based on two findings. First, the significant correlation between MUC16 and GLUT1 was verified by clinical specimen and TCGA data analysis. Then, alteration of MUC16 expression levels can affect the expression of GLUT1 and glucose uptake was also verified. Finally, this conclusion is further verified in vivo by tumour‐bearing mice model. To summarize, our results suggest that MUC16 promotes EOC proliferation and disease progression by regulating GLUT1 expression.

The AT1 receptor autoantibody causes hypoglycemia in fetal rats via promoting the STT3A-GLUT1-glucose uptake axis in liver

Blood glucose is of great importance to development and metabolic homeostasis in fetuses. Stimulation of harmful factors during gestation induces pathoglycemia. Angiotensin II type 1 receptor autoantibody (AT1-AA), a newly discovered gestational harmful factor, has been shown to induce intrauterine growth restriction in fetuses and glucose disorders in adults. However, whether and how AT1-AA influences the blood glucose level of fetuses during gestation is not yet clear. The purpose of the current study was to observe the fetal blood glucose level of AT1-AA-positive pregnant rats during late pregnancy and to determine the roles that hepatic glucose transporters play in this process. We established AT1-AA-positive pregnant rats by injecting AT1-AA into the caudal veins of rats in the 2nd trimester of gestation. Although the fetal blood glucose level in the 3rd trimester of gestation decreased, hepatic glucose uptake increased detected. Through separating membrane and cytosolic proteins, we demonstrated that both the expression and membrane transport ratio of glucose transporter 1 (GLUT1), which is responsible for glucose transport in fetal hepatocytes, were upregulated, accompanied by increased expression of N-glycosyltransferase STT3A, which contributes to the N-glycosylation of GLUT1. In vitro, we identified that AT1-AA increased glucose uptake, the expression and membrane transport ratio of GLUT1 and the expression of STT3A in HepG2 cell lines via separating membrane and cytosolic proteins and immunofluorescence, resulting in the decreased glucose content in the medium. The GLUT1 inhibitor WZB117 reversed the decreases in glucose content in the medium, the increases in glucose uptake, the increases in the expression and membrane transport ratio of GLUT1 caused by AT1-AA. The N-glycosyltransferase inhibitor NGI as well as si-STT3A reversed the AT1-AA-induced upregulation of the STT3A-GLUT1-glucose uptake effect. This study demonstrates that AT1-AA lowers the blood glucose level of fetuses via the STT3A-GLUT1-glucose uptake axis in liver.

HPV 16 E6/E7 Promote the Glucose Uptake of GLUT1 in Lung Cancer Through Downregulation of TXNIP Due to Inhibition of PTEN Phosphorylation

High-risk human papillomavirus (HPV) infection play an important role in the development of lung cancer. Our previously study showed that E6 and E7 in HPV16 upregulated the expression of GLUT1 in lung cancer cells. However, whether they can promote the glucose uptake by GLUT1 and the underlying molecular mechanism has not been identified. It has been reported that thioredoxin interacting protein (TXNIP) regulates both the expression of GLUT1 and its glucose uptake. We speculate that high risk HPV16 infection may be closely related to TXNIP expression. Therefore, we associate HPV16 with TXNIP to explore the potential molecular mechanism of their regulation of GLUT1 expression and glucose uptake. Using double directional genetic manipulation in lung cancer cells, we showed that HPV16 E6/E7 proteins downregulated the expression of p-PTEN in lung cancer cells, the knockdown of PTEN further inhibited the expression of TXNIP, the inhibition of TXNIP further promoted the accumulation of HIF-1α by inhibiting the translocation of nuclear HIF-1α to the cytoplasm, and subsequently upregulated the expression of GLUT1 at the protein and mRNA levels. More interestingly, we found that the knockdown of TXNIP played a decisive role to promote the glucose uptake by GLUT1. Together, these findings suggested that the PTEN-TXNIP-HIF-1α axis might be related to the E6/E7-mediated expression of GLUT1 and its glucose uptake.

Role of GLUT-1 in the Upregulation of PD-L1 Expression After Radiotherapy and Association of PD-L1 with Favourable Overall Survival in Hypopharyngeal Cancer

Purpose

The alteration of tumor immunity after radiotherapy (RT) has been widely studied in recent years. However, the mechanism through which RT mediates tumor immunity and the involvement of glycolysis in this mediation in hypopharyngeal cancer remain unclear. This study investigated whether RT regulates programmed cell death ligand 1(PD-L1) partly via glucose transporter 1(GLUT-1) expression and whether PD-L1 expression predicts overall survival (OS) in patients with hypopharyngeal cancer.

Methods

The expression of PD-L1 and Glut-1, and the numbers of CD4+, CD8+ T cells were detected by immunohistochemical analysis on 47 pre-RT and 25 post-RT specimens of hypopharyngeal cancer. Changes in these indicators before and after RT were compared, and their association with the OS of patients was analyzed. Moreover, we used siRNA-GLUT-1 to inhibit GLUT-1 expression and examined whether GLUT-1 was a key factor involved in the mediation of PD-L1 expression by RT in vitro.

Results

In the multivariate analysis, patients with higher PD-L1 expression (p=0.037), higher CD4+ T cell infiltration (p=0.016) and earlier clinical stage (p=0.019) had favourable OS. The expression of PD-L1, and the CD4+ and CD8+ T cells was markedly increased following RT. PD-L1 expression was correlated with Glut-1 pre-RT (p=0.002), but not after RT (p=0.051). The expression of PD-L1 in FaDu cells was upregulated after RT, especially at 96h after RT in vitro. However, the expression of PD-L1 in siRNA-GLUT-1 FaDu cells was markedly decreased at 96h after RT compared with that measured in FaDu cells.

Conclusion

Patients with high PD-L1 expression and CD4+ T cell infiltration may have favourable OS in hypopharyngeal cancer. RT may increase PD-L1 expression and alter tumor immunity. The expression of PD-L1 was correlated with Glut-1, and inhibition of GLUT-1 expression may decrease the expression of PD-L1. GLUT-1 may participate in the alteration of tumor immunity after RT.

Progesterone Regulates Glucose Metabolism Through Glucose Transporter 1 to Promote Endometrial Receptivity

Successful embryo implantation requires receptive endometrium, which is conducive to the process of embryo recognition, adhesion, and invasion within a certain period of time and is inseparable from the dynamic interaction between 17β-estradiol (E2) and progesterone (P4). Proper glucose metabolism is critical for the profound physiological changes in the endometrium entering the receptive state. And glucose transporters (GLUTs) are responsible for intracellular uptake of glucose and are the first step in glucose metabolism. Prior literature has reported the presence of GLUTs in the endometrium. However, we still do not understand the specific mechanisms of this process. In this study, we identified the effect of P4 on glucose transporter 1 (GLUT1) using in vivo animal models and determined the regulation of glucose metabolism by P4 in cells. We highly suspect that this pregnancy failure may be due to reduced GLUT1-mediated glucose metabolism, resulting in a decrease in endometrial receptivity caused by an inadequate energy supply and synthesis of substrate. Here, we propose a possible mechanism to explain how embryo implantation is affected by P4 and glucose utilization under abnormal endometrial conditions.

S6 ribosomal protein phosphorylation is associated with malignancy of intraductal papillary mucinous neoplasm of the pancreas

BACKGROUND

Glucose metabolism of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas is unclear. S6 ribosomal protein (S6) phosphorylation is involved not only in controlling cell growth but also in glucose metabolism in cancer. The aim of this study was to investigate the role of S6 phosphorylation and the significance of glucose metabolic changes in IPMN.

METHODS

Records of 39 patients who underwent preoperative FDG-PET and curative resection were enrolled in this study. S6 phosphorylation and GLUT1 expression were evaluated immunohistochemically in these patients. The effect of S6 phosphorylation on glucose uptake was examined in cancer cell lines. To examine the change of glucose metabolism in IPMN clinically, the relation between clinical factors including FDG-PET and malignancy of IPMN was investigated.

RESULTS

S6 phosphorylation and GLUT1 expression were significantly higher in carcinoma than in normal cells or adenoma. Cell lines with high level of S6 phosphorylation showed high glucose uptake, and inhibition of S6 phosphorylation reduced glucose uptake. In clinical examination, FDG-PET was the independent factor related to the diagnosis of adenoma or carcinoma (odds ratio = 20.0, 95% confidence interval = 1.837-539.9, P = .012). FDG-PET detected carcinoma with a sensitivity of 81.8%, specificity of 96.4%, and accuracy of 92.3%.

CONCLUSION

S6 phosphorylation was associated with glucose uptake and malignancy of IPMN. Moreover, glucose uptake increased in malignant cells of IPMN, and FDG-PET is useful for detecting malignancy of IPMN.

Expression of hypoxia-inducible factor 1α, glucose transporter 1, and hexokinase 2 in primary central nervous system lymphoma and the correlation with the biological behaviors

BACKGROUND

It has been indicated that abnormal glucose metabolism mediated by hypoxia-inducible factor 1α (HIF-1α) played an essential role in the development of solid tumor. However, there were rare studies about the role of them in primary central nervous system lymphoma (PCNSL).

OBJECTIVE

To investigate the protein levels of HIF-1α, glucose transporter 1 (GLUT1), and hexokinase 2 (HK2) in PCNSL and whether their levels are associated with prognostic factors.

METHODS

Expression of HIF-1α, GLUT1, and HK2 in 39 tumor tissues was evaluated by immunohistochemical stainning. The correlation of the expression of HIF-1α with the protein level of GLUT1 and HK2 was investigated. In addition, the association between these protein expression levels and clinical parameters and prognosis was analyzed.

RESULTS

In the tumor specimens of PCNSL, positive stainings of HIF-1α, GLUT1, and HK2 were in 23 patients (58.97%), 25 patients (64.1%), and 26 patients (66.67%), respectively, which were associated with the expression level of lactic dehydrogenase (LDH), but not with age, gender, number of lesion, ECOG score, or deep structure. The expression of HIF-1α was positively correlated with the expression of GLUT1 (p < .01, r = .749) and HK2 (p < .01, r = .787). Univariate analysis showed that upregulated GLUT1 was unfavorable predictors of progression-free survival (PFS) in PCNSL. The results of Cox proportional hazards model showed GLUT1 was significantly associated with shorter PFS (hazard ration: 5.65; 95% confidence interval: 1.23-25.84; p = .026).

CONCLUSIONS

This study indicated that there was a hypoxic microenvironment and HIF-1α was involved in the regulation of glycolysis pathway in PCNSL. GLUT1 might be a potential marker for shorter PFS in PCNSL.

Thioredoxin interacting protein (TXNIP) acts as a tumor suppressor in human prostate cancer

Prostate cancer (PCa) is one of the most common malignant tumors in the world. Thioredoxin interacting protein (TXNIP) is downregulated in a variety of human tumors and plays an important role in tumor suppression. However, the expression level and biological functions of TXNIP in PCa have not been identified yet. Therefore, this study aims to investigate the expression and biological functions of TXNIP in PCa. We reported that the expression of TXNIP was significantly decreased in PCa and associated with clinicopathological features. Overexpression of TXNIP could significantly inhibited PC-3 cells proliferation, migration, invasion, and glucose uptake. Additionally, overexpression of TXNIP could remarkably block cell cycle in the G0/G1 phase and promoted cell apoptosis. Furthermore, TXNIP expression correlated inversely with GLUT1 expression in PCa. Taken together, our results for the first time revealed that TXNIP was decreased in PCa. Moreover, TXNIP might act as a tumor suppressor of PCa and correlated with tumor occurrence and development. Our findings cast a new light on better understanding the occurrence and development of PCa and indicated that TXNIP might be favorable for PCa molecular target therapy.

MicroRNA-125b reduces glucose uptake in papillary thyroid carcinoma cells

Previous studies have shown that microRNA (miR)-125b plays important roles in several human cancer types. The aim of the present study was to analyze the potential roles of miR-125b in papillary thyroid carcinoma (PTC). It was found that miR-125b was downregulated in PTC and its expression was affected by clinical stages. Glucose transporter 1 (GLUT1) was upregulated in PTC and was negatively correlated with miR-125b. In PTC cells, overexpression of miR-125b suppressed glucose uptake and downregulated GLUT1. Furthermore, GLUT1 overexpression reduced the effects of miR-125b overexpression on glucose uptake. Moreover, miR-125b overexpression suppressed PTC cell proliferation. GLUT1 overexpression promoted the proliferation of PTC cells and reduced the effects of miR-125b overexpression on cancer cell proliferation. Overall, miR-125b decreased glucose uptake in PTC cells by downregulating GLUT1.

[Effect of Sijunzi Decoction on regulation of Aβ-related proteins across blood-brain barrier]

According to traditional Chinese medicine, &quot;spleen transport&quot; is closely related to the metabolism of substance and energy. Studies have shown that Alzheimer's disease(AD) is a disease related to glucose and lipid metabolism and energy metabolism. The traditional Chinese medicine Jiangpi Recipe can improve the learning ability and memory of AD animal model. Sijunzi Decoction originated from Taiping Huimin Hefang Prescription is the basic prescription for strengthening and nourishing the spleen, with the effects of nourishing Qi and strengthening the spleen. In this experiment, human brain microvascular endothelial cells(HBMEC) and Sijunzi Decoction water extract(0.25, 0.5, 1 mg·L~(-1)) were pre-incubated for 2 h, and then Aβ_(25-35) oligomers(final concentration 40 μmol·L~(-1)) was added for co-culture for 22 hours. The effect of Sijunzi Decoction on the activity of Aβ_(25-35) oligomer injured cells and the expression of related proteins were investigated. Q-TOF-LC-MS was used first for principal component analysis of Sijunzi Decoction water extract. Then MTT assay was used to investigate the effect of Sijunzi Decoction water extract on the proliferation of HBMEC cells. Real-time fluorescence quantitative PCR(RT-qPCR) was employed to detect the mRNA expression of GLUT1, RAGE, and LRP1. The expression of Aβ-related proteins across blood-brain barrier(RAGE, LRP1) was detected by Western blot. The results showed that 40 μmol·L~(-1) Aβ_(25-35) oligomers could induce endothelial cell damage, reduce cell survival, increase expression of RAGE mRNA and RAGE protein, and reduce expression of GLUT1 mRNA, LRP1 mRNA, and LRP1 protein. Sijunzi Decoction water extract could reduce the Aβ_(25-35) oligomer-induced cytotoxicity of HBMEC, decrease the expression of RAGE mRNA and RAGE protein, and increase the expression of GLUT1 mRNA, LRP1 mRNA and LRP1 protein. The results indicated that Sijunzi Decoction could reduce the injury of HBMEC cells induced by Aβ_(25-35) oligomer, and regulate the transport-related proteins GLUT1, RAGE and LRP1, which might be the mechanism of regulating Aβ_(25-35) transport across the blood-brain barrier.

Distinct roles of ezrin, radixin and moesin in maintaining the plasma membrane localizations and functions of human blood-brain barrier transporters

The purpose of this study was to clarify the roles of ERM proteins (ezrin/radixin/moesin) in the regulation of membrane localization and transport activity of transporters at the human blood-brain barrier (BBB). Ezrin or moesin knockdown in a human in vitro BBB model cell line (hCMEC/D3) reduced both BCRP and GLUT1 protein expression levels on the plasma membrane. Radixin knockdown reduced not only BCRP and GLUT1, but also P-gp membrane expression. These results indicate that P-gp, BCRP and GLUT1 proteins are maintained on the plasma membrane via different ERM proteins. Furthermore, moesin knockdown caused the largest decrease of P-gp and BCRP efflux activity among the ERM proteins, whereas GLUT1 influx activity was similarly reduced by knockdown of each ERM protein. To investigate how moesin knockdown reduced P-gp efflux activity without loss of P-gp from the plasma membrane, we examined the role of PKCβI. PKCβI increased P-gp phosphorylation and reduced P-gp efflux activity. Radixin and moesin proteins were detected in isolated human brain capillaries, and their protein abundances were within a 3-fold range, compared with those in hCMEC/D3 cell line. These findings may mean that ezrin, radixin and moesin maintain the functions of different transporters in different ways at the human BBB.

Overexpression of METTL3 associated with the metabolic status on 18F-FDG PET/CT in patients with Esophageal Carcinoma

Background: To investigate the expression of methyltransferase 3 (METTL3) and its relationship with ¹⁸F-FDG uptake in patients with esophageal carcinoma (ESCA). Materials and methods: This study analyzed the expression of METTL3 in ESCA and its relationship with clinicopathological features by The Cancer Genome Atlas (TCGA) database. Immunohistochemical staining was performed on 57 tumor tissues of ESCA patients who underwent PET/CT scan before surgery to evaluate the expression of METTL3, glucose transporter 1 (GLUT1), and hexokinase 2 (HK2) in tumor tissues and peritumoral tissues. Analyze the relationship between SUVmax with METTL3, HK2, and GLUT1 expression. Results: The expression of METTL3, GLUT1, and HK2 was significantly increased in ESCA tissues compared with normal tissues (p < 0.001). The expression of METTL3 was correlated with tumor size and histological differentiation (p < 0.05), and there was no significant difference between age, sex, pathological types, tumor staging, or lymph node metastasis (p > 0.05). The SUVmax was significantly higher in tumors with high METTL3 expression (17.822±6.249) compared to low METTL3 expression (9.573±5.082) (p < 0.001). There was a positive correlation between the SUVmax and METTL3 expression in ESCA (r² = 0.647, p < 0.001). Multivariate analysis confirmed the association between SUVmax and METTL3 expression (p < 0.05). GLUT1 and HK2 expression in ESCA was positively correlated with ¹⁸F-FDG uptake and METTL3 status (p < 0.001). Conclusions: The high expression of METTL3 is related to the high SUVmax in ESCA, and METTL3 may increase ¹⁸F-FDG uptake by regulating GLUT1 and HK2.

Benign neonatal hemangiomatosis with early regression of skin lesions: A case report and review of the published work

A 2-day-old Japanese male infant was referred to our outpatient clinic for multiple cutaneous hemangiomas present since birth. Physical examination revealed 14 small, well-circumscribed red papules, scattered over the head, face, dorsum of the right hand, trunk, lower extremities, buttocks and penis. Ultrasound examination revealed no evidence of visceral involvement. Histological examination of a cutaneous lesion was consistent with infantile hemangioma, resulting in the final diagnosis of benign neonatal hemangiomatosis (BNH). The hemangiomas enlarged by 1 month of age and began to resolve at 2 months of age. Within the next month, the lesions had almost completely disappeared. BNH is a rare, non-heritable, self-limited, benign disease characterized by multiple cutaneous infantile hemangiomas and no or unremarkable visceral lesions. Generally, BNH lesions spontaneously regress within the first 1-2 years of life or within 4 months of onset. However, there have been no detailed reports about the time course of BNH. To our knowledge, 31 cases of BNH without hepatic hemangiomas, excluding this case, have been reported so far. Twenty-one of these cases demonstrated spontaneous regression of the cutaneous hemangiomas without treatment. In all cases, the cutaneous hemangiomas were present at birth. The median age at the beginning of spontaneous regression was 6.0 months (range, 1-12) and the median age at complete or almost complete regression was 15 months (range, 3-28). Cutaneous hemangiomas in BNH without hepatic hemangiomas undergo spontaneous regression within the first year of life.

LncRNA-SNHG16 Silencing Inhibits Prostate Carcinoma Cell Growth, Downregulate GLUT1 Expression and Reduce Glucose Uptake

Background

lncRNA-SNHG16 was identified as an oncogene in many cancers, but its involvement in prostate carcinoma is unknown.

Material and Method

Expression of lncRNA-SNHG16 and glucose transporter 1 (GLUT-1) in 52 prostate carcinoma tissues and 36 normal prostate tissues was analyzed by RT-qPCR. Transfections were performed to analyze gene interactions. Cell proliferation was analyzed by cell proliferation assay.

Results

Overexpression of lncRNA-SNHG16 effectively distinguished prostate carcinoma patients from normal ones. Expression levels of lncRNA-SNHG16 and GLUT-1 mRNA were significantly and positively correlated across prostate carcinoma tissues. In vitro cancer cell experiments revealed that lncRNA-SNHG16 siRNA silencing downregulated the expressions of GLUT-1 and reduced glucose uptake. lncRNA-SNHG16 siRNA silencing also significantly inhibited prostate carcinoma cell proliferation. However, lncRNA-SNHG16 siRNA silencing did not affect the normal prostate.

Conclusion

In conclusion, lncRNA-SNHG16 might be a possible treatment target for prostate cancer.

Prognostic Significance of Glucose Metabolism as GLUT1 in Patients with Pulmonary Pleomorphic Carcinoma

Glucose metabolism is necessary for tumor progression, metastasis, and survival in various human cancers. Glucose transporter 1 (GLUT1), in particular, plays an important role in the mechanism of ¹⁸F-FDG (2-[¹⁸F]-fluoro-2-deoxy-d-glucose) within tumor cells. However, little is known about the clinicopathological significance of GLUT1 in patients with pulmonary pleomorphic carcinoma (PPC). Adenocarcinoma, squamous cell carcinoma, adenosquamous cell carcinoma, poorly differentiated carcinoma, large cell carcinoma, and others were identified as epithelial components, and spindle-cell type, giant-cell type, and both spindle- and giant-cell types were identified as sarcomatous components. This study was performed to determine the prognostic impact of GLUT1 expression in PPC. Patients with surgically resected PPC (n = 104) were evaluated by immunohistochemistry analysis to detect GLUT1 expression and determine the Ki-67 labeling index using specimens of the resected tumors. GLUT1 was highly expressed in 48% (50/104) of all patients, 42% (20/48) of the patients with an adenocarcinoma component, and 53% (30/56) of the patients with a nonadenocarcinoma component. High expression of GLUT1 was significantly associated with advanced stage, vascular invasion, pleural invasion, and tumor cell proliferation as determined by Ki-67 labeling. GLUT1 expression and tumor cell proliferation were significantly correlated according to the Ki-67 labeling in all patients (Spearman’s rank; r = 0.25, p < 0.01). In multivariate analysis, GLUT1 was identified as a significant independent marker for predicting a poor prognosis. GLUT1 is an independent prognostic factor for predicting the poor prognosis of patients with surgically resected PPC.

Immunohistochemistry and gene expression of GLUT1, RUNX2 and MTOR in reparative dentinogenesis

OBJECTIVES

To determine glucose transporter 1 (GLUT1) and runt-related transcription factor 2 (RUNX2) expression during reparative dentinogenesis after pulpotomy with mineral trioxide aggregate (MTA) capping.

SUBJECTS AND METHODS

Eight-week-old male Wistar rats were used. Pulp of the upper left first molar was exposed and capped with MTA. The upper right first molar of the same animal was used as a control. After collecting molars at various time points, GLUT1, RUNX2 and mammalian target of rapamycin (MTOR) were examined by immunohistochemistry. mRNA levels of Slc2a1 (encoding GLUT1), Runx2, Nestin and Mtor were determined by real-time PCR.

RESULTS

Pulp exhibited progressive formation of reparative dentine lined with GLUT1- and MTOR-immunoreactive odontoblast-like cells at 5 days after pulpotomy. RUNX2 was detected in nuclei of most pulp tissue cells at day 5 after pulpotomy. Double immunofluorescence staining revealed GLUT1 immunoreactivity on odontoblast-like cells positive for Nestin or RUNX2, 5 days after pulpotomy. Slc2a1, Runx2, Nestin and Mtor mRNA levels were significantly upregulated on days 3-5 after pulpotomy.

CONCLUSIONS

After rat molar pulpotomy, dental pulp induced formation of reparative dentine with colocalization of GLUT1 and Nestin or RUNX2. Moreover, mRNA levels of Slc2a1, Runx2, Nestin and Mtor were significantly upregulated in pulpotomized dental pulp.

In vitro measurement of glucose uptake after radiation and cetuximab treatment in head and neck cancer cell lines using 18F-FDG, gamma spectrometry and PET/CT

The standard treatment for head and neck squamous cell carcinoma (HNSCC) is radiotherapy, often in combination with chemotherapy or surgery. However, a novel monoclonal antibody, cetuximab (Erbitux^®), has also been approved for patient therapy. The aim of present study was to develop an in vitro method for the measurement of 18F-fluoro-2deoxy-D-glucose (FDG) to determine if cellular 18F-FDG uptake is associated with response to radiotherapy or cetuximab treatment. In the current study, HNSCC cell lines were treated with radiation or with cetuximab. Next, the uptake of 18F-FDG was measured using a gamma spectrometer (GS). Thereafter, uptake after radiation was measured first with GS and then compared with positron emission tomography (PET)/computed tomography (CT) imaging. Furthermore, the mRNA expression of glucose transporter 1 (GLUT1) was measured following cetuximab treatment via reverse transcription-quantitative PCR. A study protocol was developed to measure the cellular uptake of 18F-FDG via gamma-ray spectrometry and comparable results were obtained with those of clinical PET/CT. The results revealed a decrease in 18F-FDG after radiation and cetuximab treatment. The uptake of 18F-FDG following cetuximab treatment was significantly lower in the cetuximab-sensitive cell line UT-SCC-14 compared with the cetuximab-resistant cell lines UT-SCC-2 and UT-SCC-45. Furthermore, after treatment with cetuximab for 24 and 48 h, a significant increase in GLUT1 expression was detected in the sensitive cell line compared with the two resistant cell lines. In conclusion, a novel yet reliable method for the measurement of intracellular 18F-FDG via GS has been developed, and our results indicate that 18F-FDG uptake is associated with radiation and cetuximab response in HNSCC.

Inhibition of miRNA-34a promotes triple negative cancer cell proliferation by promoting glucose uptake

miRNA-34a is a tumor suppressor that is expressed in a variety of different types of cancer. The current study aimed to determine the involvement of miRNA-34a in triple negative breast cancer. miRNA-34a expression was detected using reverse transcription-quantitative PCR in the breast tissue and serum of patients with triple negative breast cancer and of healthy controls. The diagnostic value of miRNA-34a in triple negative breast cancer was analyzed using receiver operating curve analysis. A miRNA-34a inhibitor was transfected into triple negative breast cancer cells and the effects on cell proliferation, glucose uptake and glucose transporter 1 (GLUT1) expression were detected using a cell counting kit-8 assay, glucose uptake assay and western blot analysis, respectively. The results demonstrated that miRNA-34a was downregulated in patients with triple negative breast cancer compared with healthy controls and the downregulation of miRNA-34a effectively distinguished patients with triple negative breast cancer from healthy controls. miRNA-34a inhibition promoted cancer cell proliferation, accelerated glucose uptake and upregulated GLUT1. The current study concluded that the inhibition of miR-34a may promote triple negative cancer cell proliferation by promoting glucose uptake.

Wnt1-inducible signaling protein 1 regulates laryngeal squamous cell carcinoma glycolysis and chemoresistance via the YAP1/TEAD1/GLUT1 pathway

Wnt1-inducible signaling protein 1 (WISP1) is a matricellular protein and downstream target of Wnt/β-catenin signaling. This study sought to determine the role of WISP1 in glucose metabolism and chemoresistance in laryngeal squamous cell carcinoma. WISP1 expression was silenced or upregulated in Hep-2 cells by the transfection of WISP1 siRNA or AdWISP1 vector. Ectopic WISP1 expression regulated glucose uptake and lactate production in Hep-2 cells. Subsequently, the expression of glucose transporter 1 (GLUT1) was significantly modulated by WISP1. Furthermore, WISP1 increased cell survival rates, diminished cell death rates, and suppressed ataxia-telangiectasia-mutated (ATM)-mediated DNA damage response pathway in cancer cells treated with cisplatin through GLUT1. WISP1 also promoted cancer cell tumorigenicity and growth in mice implanted with Hep-2 cells. Additionally, WISP1 activated the YAP1/TEAD1 pathway that consequently contributed to the regulation of GLUT1 expression. In summary, WISP1 regulated glucose metabolism and cisplatin resistance in laryngeal cancer by regulating GLUT1 expression. WISP1 may be used as a potential therapeutic target for laryngeal cancer.

Overexpression of lncRNA GATA6-AS inhibits cancer cell proliferation in mantle cell lymphoma by downregulating GLUT1

Long non-coding RNA GATA6 antisense RNA 1 (lncRNA GATA6-AS) is a recently identified lncRNA that is involved in endothelial-mesenchymal transition. The present study aimed to investigate the involvement of GATA6-AS in the progression of mantle cell lymphoma (MCL). It was found that plasma lncRNA GATA6-AS expression level was downregulated in patients with MCL, compared with that in healthy controls. Downregulation of lncRNA GATA6-AS has potential diagnostic value in early stage MCL. Overexpression of lncRNA GATA6-AS resulted in inhibited glucose uptake in the human cell lines JVM-2 and Z-138 MCL. Inhibited expression of glucose transporter 1 (GLUT1) was observed in MCL cells following lncRNA GATA6-AS overexpression, whilst GLUT1 overexpression did not alter the expression of lncRNA GATA6-AS. Additionally, lncRNA GATA6-AS overexpression inhibited, whilst GLUT1 overexpression promoted the proliferation of JVM-2 and Z-138 MCL cells; GLUT1 overexpression partially reversed the inhibitory effects of lncRNA GATA6-AS overexpression. It was therefore concluded that lncRNA GATA6-AS may inhibit cancer cell proliferation in MCL by downregulating GLUT1.

Long non-coding RNA mortal obligate RNA transcript suppresses tumor cell proliferation in prostate carcinoma by inhibiting glucose uptake

A previous study reported the decreased expression of long non-coding RNA mortal obligate RNA transcript (lncRNA MORT) in 16 types of cancer, while the functionality of lncRNA MORT in cancer biology remains unknown. Therefore, the present study was conducted to characterize the functionality of lncRNA MORT in prostate carcinoma, a common cancer type worldwide. lncRNA MORT expression level was downregulated in tumor tissues compared with that in the adjacent healthy tissues of patients with prostate carcinoma. Expression of lncRNA MORT in tumor tissues was influenced by tumor size, but not by tumor metastasis. Overexpression of lncRNA MORT inhibited glucose uptake and glucose transporter 1 (GLUT-1) expression in prostate carcinoma cell lines; GLUT-1 overexpression upregulated glucose uptake and attenuated the effects of lncRNA MORT overexpression on glucose uptake, but did not significantly affect the expression of lncRNA MORT. Overexpression of lncRNA MORT inhibited, while GLUT-1 overexpression promoted the proliferation of prostate carcinoma cells. In addition, GLUT-1 overexpression attenuated the effects of lncRNA MORT on cell proliferation. Therefore, lncRNA MORT may inhibit cancer cell proliferation in prostate carcinoma by preventing glucose uptake.

LINC01638 lncRNA promotes cancer cell proliferation in hepatocellular carcinoma by increasing cancer cell glucose uptake

The aim of the present study was to examine the function of long intergenic non-protein coding RNA 1638 (LINC01638) long non-coding RNA (lncRNA) in hepatocellular carcinoma (HCC). In the present study, gene expression was analyzed using qPCR and western blotting. Glucose uptake was analyzed using a glucose uptake assay and cell proliferation was analyzed using a cell counting kit-8 assay. LINC01638 lncRNA and glucose transporter 1 (GLUT1) were upregulated in tumor tissues compared with adjacent healthy tissues of patients with HCC. Expression levels of LINC01638 lncRNA and GLUT1 were positively correlated only in tumor tissues; however, there was no correlation in adjacent healthy tissues. Overexpression of LINC01638 lncRNA and GLUT1 promoted glucose uptake, while LINC01638 lncRNA and GLUT1-knockdown led to inhibited glucose uptake of cells of HCC cell lines. Overexpression of LINC01638 lncRNA mediated the upregulation of GLUT1 expression and accelerated cell proliferation. GLUT1 overexpression failed to significantly affect LINC01638 lncRNA expression, however also promoted cancer cell proliferation. In addition, GLUT1-knockdown attenuated the effects of LINC01638 overexpression on cancer cell proliferation. Therefore, LINC01638 lncRNA promoted cancer cell proliferation in HCC, potentially by increasing cancer cell glucose uptake.

Protein kinase C-iota-mediated glycolysis promotes non-small-cell lung cancer progression

Purpose

To determine whether protein kinase C-iota (PKC-iota) is associated with glucose metabolism in non-small-cell lung cancer (NSCLC) and whether its regulatory effect on metabolic and biological changes observed in NSCLC can be mediated by glucose transporter 1 (GLUT1).

Patients and methods

Forty-five NSCLC patients underwent combined ¹⁸F-fludeoxyglucose (¹⁸F-FDG) positron emission tomography and computed tomography (PET/CT) before surgery, and another eighty-one NSCLC patients were followed-up for 1–91 months after tumor resection. The rate of glucose metabolism in NSCLC was quantified by measuring the maximum standardized uptake value (SUVmax) by ¹⁸F-FDG PET/CT. PKC-iota and GLUT1 in NSCLC were detected by immunostaining. In vitro, PKC-iota was knocked down, whereas GLUT1 was silenced with or without PKC-iota overexpression to identify the role of PKC-iota in glycolysis. Spearman’s rank correlation coefficient was used in the correlation analysis. Kaplan-Meier analysis was used to assess survival duration.

Results

There was a positive relationship between PKC-iota expression and SUVmax in NSCLC (r=0.649, P<0.001). PKC-iota expression also showed a positive relationship with GLUT1 in NSCLC tissues (r=0.686, P<0.001). Patients whose NSCLC tissues highly co-expressed PKC-iota and GLUT1 had worse prognosis compared with patients without high co-expression of PKC-iota and GLUT1. In vitro, PKC-iota silencing significantly decreased the expression of GLUT1 and inhibited glucose uptake and glycolysis; c-Myc silencing restrained PKC-iota-mediated GLUT1 elevation; GLUT1 knockdown remarkably suppressed PKC-iota-mediated glycolysis and cell growth.

Conclusion

In NSCLC, the rate of glucose metabolism was positively correlated with PKC-iota expression. PKC-iota increased glucose accumulation and glycolysis by upregulating c-Myc/GLUT1 signaling and is thus involved in tumor progression.

Downregulation of lncRNA AWPPH inhibits colon cancer cell proliferation by downregulating GLUT-1

Long non-coding RNA (lncRNA) associated with poor prognosis of hepatocellular carcinoma (AWPPH) serves pivotal roles in bladder cancer and liver cancer; however, to the best of our knowledge, its functionality in colon cancer has not been characterized. The present study aimed to investigate the involvement of lncRNA AWPPH in colon cancer. Serum levels of lncRNA AWPPH and glucose transporter 1 (GLUT-1) in patients with early stage colon cancer and healthy controls were measured by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and ELISA. Correlation between lncRNA AWPPH and GLUT-1 expression was analyzed by Pearson's correlation coefficient. χ² test was performed to investigate the associations between serum levels of lncRNA AWPPH and clinical data of patients with colon cancer. lncRNA AWPPH short hairpin RNA and GLUT-1 expression vectors were transfected into colon cancer cells, and the effects on lncRNA AWPPH, GLUT-1 and cell proliferation were detected by RT-qPCR, western blotting and Cell Counting Kit-8 assay. It was observed that serum levels of lncRNA AWPPH and GLUT-1 were significantly higher in patients with colon cancer patients compared with healthy controls. Serum levels of AWPPH and GLUT-1 were significantly positively correlated in patients with colon cancer. Serum levels of lncRNA AWPPH were associated with the tumor size. Furthermore, AWPPH-silencing significantly inhibited GLUT-1 expression and inhibited cancer cell proliferation. GLUT-1 overexpression promoted cancer cell proliferation and attenuated the inhibitory effects of AWPPH-silencing on cancer cell proliferation. However, GLUT-1 overexpression failed to significantly affect the expression of AWPPH. Therefore, it can be concluded that a downregulation of lncRNA AWPPH may inhibit colon cancer cell proliferation by downregulating GLUT-1.

Long non-coding RNA HAND2-AS1 targets glucose metabolism and inhibits cancer cell proliferation in osteosarcoma

Long non-coding RNA heart and neural crest derivatives expressed 2-antisense RNA 1 (lncRNA HAND2-AS1) is a known tumor suppressor gene in endometrioid endometrial carcinoma; however, its function in osteosarcoma is currently unknown. In the present study, HAND2-AS1 expression in the tumor tissues and adjacent healthy tissues of patients with osteosarcoma, and in the serum of patients and heathy controls was detected by reverse transcription-quantitative polymerase chain reaction. lncRNA HAND2-AS1 small interfering RNA was transfected into osteosarcoma cells, and cell proliferation, glucose transporter 1 (GLUT1) expression and glucose uptake were detected using the Cell Counting Kit-8, western blotting and glucose uptake assays, respectively. The results revealed that the expression levels of HAND2-AS1 were reduced in cancer tissues compared with those in healthy tissues. Levels of HAND2-AS1 were also reduced in the serum of patients with osteosarcoma compared with those of the control subjects. A significant association was observed between serum levels of HAND2-AS1 and tumor size, but not tumor metastasis. HAND2-AS1-knockdown promoted osteosarcoma cell proliferation, increased glucose uptake and upregulated GLUT1 expression. It was therefore concluded that lncRNA HAND2-AS1 may inhibit the proliferation of osteosarcoma cells by targeting glucose metabolism.

Correlation and expression analysis of hypoxia-inducible factor 1α, glucose transporter 1 and lactate dehydrogenase 5 in human gastric cancer

The development and identification of novel potential targeting sites for intervention therapy are essential in the search for improved treatment methods for gastric cancer (GC). Previously, it has been reported that hypoxia inducible factor-1α (HIF-1α) is a potential target gene involved in the endogenous hypoxic response and bioenergetic metabolism of GC cells. In the present study, with the assumption of a close interplay among HIF-1α, glucose transporter 1 (GLUT1) and lactate dehydrogenase-5 (LDH-5), 85 patients with GC were recruited and the protein and gene expression levels of HIF-1α, GLUT1 and LDH-5 in tumor tissues were evaluated in order to assess clinical correlations and co-expression patterns, using Immunohistochemical staining and reverse transcription-quantitative polymerase chain reaction. The results demonstrated that the protein and gene expression levels of HIF-1α were significantly associated with the depth of invasion, nodal metastasis, clinical stage, differentiation and distant metastasis. Consistent with the protein expression results, the mRNA expression levels of the genes coding for GLUT1 and LDH-5 were clearly associated with tumor size, depth of invasion, distant metastasis, clinical stage and differentiation. Correlation analysis of HIF-1α with GLUT1 and LDH-5 at the protein and mRNA expression levels in gastric carcinoma indicated that HIF-1α expression was positively correlated with the expression of GLUT1 (P<0.01, r=0.765 for mRNA expression; P<0.01, r=0.697 for protein expression) and LDH-5 (P<0.01, r=0.892 for mRNA expression; P<0.01, r=0.783 for protein expression) at the mRNA and protein levels. Therefore, it may be concluded that HIF-1α, GLUT1 and LDH-5 are potential target genes involved in the endogenous tumor response to hypoxia and the inhibition of tumor energy metabolism, highlighting a novel therapeutic target for GC.

Breaking Glucose Transporter 1/Pyruvate Kinase M2 Glycolytic Loop Is Required for Cantharidin Inhibition of Metastasis in Highly Metastatic Breast Cancer

Aerobic glycolysis plays a decisive role in cancer growth. However, its role in cancer metastasis was rarely understood. Cantharidin a natural compound from an arthropod insect cantharis exerts potent anticancer activity. Here we found cantharidin possesses significant anti-metastatic activity on breast cancer dependent on inhibition of aerobic glycolysis. Cantharidin indicates significant inhibition on migration and invasion of breast cancer cells, angiogenesis in vitro, and inhibits breast cancer cells metastasizing to liver and lung in vivo. Subsequent results revealed that cantharidin decreases the extracellular acidification rates (ECAR) but increases the oxygen consumption rates (OCR) in high metastatic cells, leading to suppression of aerobic glycolysis. This was considered to be due to inhibiting the activity of pyruvate kinase (PK) and further blocking pyruvate kinase M2 (PKM2) translocation in nucleus. Fructose-1,6-bisphosphate (FBP) and L-cysteine can significantly reverse cantharidin inhibition on breast cancer cell migration, invasion, and PKM2 translocation. Furthermore, glucose transporter 1 (GLUT1) forming a metabolic loop with PKM2 is downregulated, as well as epidermal growth factor receptor (EGFR), the regulator of the glycolytic loop. Totally, cantharidin inhibits the PKM2 nuclear translocation and breaks GLUT1/PKM2 glycolytic loop, resulting in aerobic glycolysis transformation to oxidation and subsequent reversing the metastases in breast cancer. Based on inhibiting multi signals mediated aerobic glycolysis, cantharidin could be prospectively used for prevention of metastasis in breast cancer patients.

miRNA-10a promotes cancer cell proliferation in oral squamous cell carcinoma by upregulating GLUT1 and promoting glucose metabolism

MicroRNA-10a (miRNA-10a) promotes lung cancer; however, to the best of our knowledge, its involvement in other cancer types is unknown. The present study aimed to investigate the role of miRNA-10a in oral cancer. Expression levels of miRNA-10a and glucose transporter 1 (GLUT1) in tumor tissues and adjacent healthy tissues obtained from patients with oral squamous cell carcinoma (OSCC) were detected by reverse transcription-quantitative polymerase chain reaction. Correlation analysis between the expression levels of miRNA-10a and GLUT1 was performed using Pearson's correlation coefficient. It was identified that miRNA-10a and GLUT1 were upregulated in tumor tissues compared with adjacent healthy tissues of patients with OSCC. Expression levels of miRNA-10a and GLUT1 were positively correlated in tumor tissues but not in adjacent healthy tissues. In addition, miRNA-10a overexpression promoted glucose uptake and upregulated GLUT1 in OSCC cells. Furthermore, GLUT1 overexpression promoted glucose uptake; however, no significant increase in the expression level of miRNA-10a in OSCC cells was detected. Overexpression of miRNA-10a and GLUT1 promoted OSCC cell proliferation, while GLUT1-knockdown inhibited OSCC cell proliferation. GLUT1-knockdown also attenuated the enhancing effect of miRNA-10a overexpression on cancer cell proliferation. Therefore, miRNA-10a may promote cancer cell proliferation in OSCC by upregulating GLUT1 and promoting glucose metabolism.