Metabolic reprogramming results in abnormal glycolysis in gastric cancer: a review

Glycolysis-related five-gene signature correlates with prognosis and immune infiltration in gastric cancer

BACKGROUND

Gastric cancer (GC) is one of the most common malignancies worldwide. Glycolysis has been demonstrated to be pivotal for the carcinogenesis of GC.

AIM

To develop a glycolysis-based gene signature for prognostic evaluation in GC patients.

METHODS

Differentially expressed genes correlated with glycolysis were identified in stomach adenocarcinoma data (STAD). A risk score was established through a univariate Cox and least absolute shrinkage and selection operator analysis. The model was evaluated using the area under the receiver operating characteristic curves. RNA-sequencing data from high- and low-glycolysis groups of STAD patients were analyzed using Cibersort algorithm and Spearman correlation to analyze the interaction of immune cell infiltration and glycolysis. Multiomics characteristics in different glycolysis status were also analyzed.

RESULTS

A five-gene signature comprising syndecan 2, versican, malic enzyme 1, pyruvate carboxylase and SRY-box transcription factor 9 was constructed. Patients were separated to high- or low-glycolysis groups according to risk scores. Overall survival of patients with high glycolysis was poorer. The sensitivity and specificity of the model in prediction of survival of GC patients were also observed by receiver operating characteristic curves. A nomogram including clinicopathological characteristics and the risk score also showed good prediction for 3- and 5-year overall survival. Gene set variation analysis showed that high-glycolysis patients were related to dysregulation of pancreas beta cells and estrogen late pathways, and low-glycolysis patients were related to Myc targets, oxidative phosphorylation, mechanistic target of rapamycin complex 1 signaling and G2M checkpoint pathways. Tumor-infiltrating immune cells and multiomics analysis suggested that the different glycolysis status was significantly correlated with multiple immune cell infiltration. The patients with high glycolysis had lower tumor mutational burden and neoantigen load, higher incidence of microsatellite instability and lower chemosensitivity. High glycolysis status was often found among patients with grade 2/3 cancer or poor prognosis.

CONCLUSION

The genetic characteristics revealed by glycolysis could predict the prognosis of GC. High glycolysis significantly affects GC phenotype, but the detailed mechanism needs to be further studied.

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.

A Novel Signature Based on m6A Regulator-Mediated Genes Along Glycolytic Pathway Predicts Prognosis and Immunotherapy Responses of Gastric Cancer Patients

N6-methyladenosine (m6A) modification is involved in many aspects of gastric cancer (GC). Moreover, m6A and glycolysis-related genes (GRGs) play important roles in immunotherapeutic and prognostic implication of GC. However, GRGs involved in m6A regulation have never been analyzed comprehensively in GC. Herein, the study aims to identify and validate a novel signature based on m6A-related GRGs in GC patients. Therefore, a m6A-related GRGs signature is established, which can predict the survival of patients with GC and remain an independent prognostic factor in multivariate analyses. Clinical significance of the model is well validated in internal cohort and independent validation cohort. In addition, the expression levels of risk model-related GRGs in clinical samples are validated. Consistent with the database results, all model genes are up-regulated in expression except DCN. After regrouping the patients based on this risk model, the study can effectively distinguish between them in respect to immune-cell infiltration microenvironment and immunotherapeutic response. Additionally, candidate drugs targeting risk model-related GRGs are confirmed. Finally, a nomogram combining risk scores and clinical parameters is created, and calibration plots show that the nomogram can accurately predict survival. This risk model can serve as a reliable assessment tool for predicting prognosis and immunotherapeutic responses in GC patients.

MicroRNA Let-7a association with glycolysis-induced autophagy in locally advanced gastric cancer: Their role in prognosis and FLOT chemotherapy resistance

Locally advanced gastric cancer (LAGC) still poses a clinical challenge despite multimodality treatment due to multidrug resistance (MDR). Recently, research suggested that autophagy and metabolic regulation may be potential anticancer targets due to their crucial roles in MDR. Let-7a participates in glycolytic and autophagic regulations which are both essential for tumor progression and resistance to therapy. This study used IHC stains; GLUT4 and LC3B to evaluate glycolysis and autophagy respectively. Moreover, mRNA Let-7a was detected by quantitative reverse transcription PCR (q-PCR) in 53 cases of LAGC. Elevated glycolysis and autophagy in LAGC tissue specimens as indicated by high GLUT4 and LC3B expression were significantly associated with adverse prognostic factors such as high pathological grade, positive nodal metastasis, and advanced T stage. Lower Let-7a levels were significantly associated with high tumor grade and advanced T stage. A significant positive correlation between GLUT4 and LC3B expression was detected. Significant inverse correlations between let7a level and IHC expression of both GLUT4 and LC3B were found. Elevated glycolysis and autophagy were significantly associated with poor overall survival (OS). Furthermore, low levels of let-7a were significantly associated with poor OS compared to high levels. Glycolysis and autophagy in LAGC were significantly associated with poor FLOT chemotherapy response. Let7a mRNA relative expression was significantly decreased in cases showing post therapy partial response and sustained disease. Multivariate analysis showed that histologic tumor type, high GLUT4 and high LC3B expression were independent factors associated with poor OS. Poor survival and post FLOT chemotherapy resistance in LAGC cases were significantly related to elevated glycolysis, elevated autophagy, and reduced Let-7a expression. Accordingly, combined therapeutic targeting of these pathways could enhance chemosensitivity in LAGC.

CircRNA LDLR promotes proliferation and aerobic glycolysis of gastric cancer cells by targeting CHD1 with miR-449b-5p

Background/aim

Circular RNAs can serve as detection biomarkers and therapeutic targets for tumors. Our study aimed to elucidate the mechanisms associated with circRNA LDLR (circLDLR) in gastric cancer (GC) proliferation and aerobic glycolysis.

Materials and methods

Expression signatures of circLDLR, miR-449b-5p, and CHD1 were examined in GC samples using quantitative PCR. Proliferation ability of MKN-45 cells was assessed via CCK-8 and EdU assays, and cell apoptosis was measured by flow cytometry. Glucose uptake, lactate production, ATP/ADP ratios, and NAD+/NADH ratios in cell supernatants were quantified to evaluate aerobic glycolysis. Subcellular isolation assay, quantitative PCR, immunoblot analysis, RNA immunoprecipitation (RIP), and dual luciferase reporter assay were employed to investigate the relationship between genes.

Results

Expression of circLDLR and CHD1 was elevated, while miR-449b-5p expression decreased in GC. Functionally, overexpression of circLDLR enhanced proliferation and aerobic glycolysis and hampered apoptosis of MKN-45 cells. However, upregulation of miR-449b-5p or downregulation of CHD1 reversed these effects. CircLDLR acted as an miRNA spongeand regulated the expression of miR-449b-5p, thereby affecting CHD1 and accelerating GC malignant progression.

Conclusion

CircLDLR drives the proliferation and aerobic glycolysis of GC cells by targeting CHD1 with miR-449b-5p, which is an ideal potential target for early diagnosis and clinical treatment of GC.

Discovery of a novel lipid metabolism-related gene signature to predict outcomes and the tumor immune microenvironment in gastric cancer by integrated analysis of single-cell and bulk RNA sequencing

Gastric cancer (GC) is a pressing global clinical issue, with few treatment options and a poor prognosis. The onset and spread of stomach cancer are significantly influenced by changes in lipid metabolism-related pathways. This study aimed to discover a predictive signature for GC using lipid metabolism-related genes (LMRGs) and examine its correlation with the tumor immune microenvironment (TIME). Transcriptome data and clinical information from patients with GC were collected from the TCGA and GEO databases. Data from GC samples were analyzed using both bulk RNA-seq and single-cell sequencing of RNA (scRNA-seq). To identify survival-related differentially expressed LMRGs (DE-LMRGs), differential expression and prognosis studies were carried out. We built a predictive signature using LASSO regression and tested it on the TCGA and GSE84437 datasets. In addition, the correlation of the prognostic signature with the TIME was comprehensively analyzed. In this study, we identified 258 DE-LMRGs in GC and further screened seven survival-related DE-LMRGs. The results of scRNA-seq identified 688 differentially expressed genes (DEGs) between the three branches. Two critical genes (GPX3 and NNMT) were identified using the above two gene groups. In addition, a predictive risk score that relies on GPX3 and NNMT was developed. Survival studies in both the TCGA and GEO datasets revealed that patients categorized to be at low danger had a significantly greater prognosis than those identified to be at high danger. Additionally, by employing calibration plots based on TCGA data, the study demonstrated the substantial predictive capacity of a prognostic nomogram, which incorporated a risk score along with various clinical factors. Within the high-risk group, there was a noticeable abundance of active natural killer (NK) cells, quiescent monocytes, macrophages, mast cells, and activated CD4 + T cells. In summary, a two-gene signature and a predictive nomogram have been developed, offering accurate prognostic predictions for general survival in GC patients. These findings have the potential to assist healthcare professionals in making informed medical decisions and providing personalized treatment approaches.

Genome-wide association study of mammary gland tumors in Maltese dogs

Background

A genome-wide association study (GWAS) is a valuable tool for investigating genetic and phenotypic variation in many diseases.

Objective

The objective of this study was to identify variations in the genomes of Maltese dogs that are associated with the mammary gland tumor (MGT) phenotype and to assess the association between each biological condition and MGT phenotype in Maltese dogs.

Methods

DNA was extracted from 22 tumor samples and 11 whole blood samples from dogs with MGTs. Genome-wide single-nucleotide polymorphism (SNP) genotyping was performed, and the top 20 SNPs associated with various conditions and genetic variations were mapped to their corresponding gene locations.

Results

The genotyping process successfully identified 173,662 loci, with an overall genotype completion rate of 99.92%. Through the quality control analysis, 46,912 of these SNPs were excluded. Allelic tests were conducted to generate Manhattan plots, which showed several significant SNPs associated with MGT phenotype in intergenic region. The most prominent SNP, located within a region associated with transcription and linked to the malignancy grade of MGT, was identified on chromosome 5 (p = 0.00001) though there may be lack of statistical significance. Other SNPs were also found in several genes associated with oncogenesis, including TNFSF18, WDR3, ASIC5, STAR, and IL1RAP.

Conclusion

To our knowledge, this is the first GWAS to analyze the genetic predisposition to MGT in Maltese dogs. Despite the limited number of cases, these analyzed data could provide the basis for further research on the genetic predisposition to MGTs in Maltese dogs.

Plasma Exosome Proteins ILK1 and CD14 Correlated with Organ-Specific Metastasis in Advanced Gastric Cancer Patients

The exosome plays important roles in driving tumor metastasis, while the role of exosome proteins during organ-specific metastasis in gastric cancer has not been fully understood. To address this question, peripheral blood samples from 12 AGC patients with organ-specific metastasis, including distant lymphatic, hepatic and peritoneal metastasis, were collected to purify exosomes and to detect exosome proteins by Nano-HPLC-MS/MS. Gastric cancer cell lines were used for in vitro experiments. Peripheral blood sample and ascites sample from one patient were further analyzed by single-cell RNA sequencing. GO and KEGG enrichment analysis showed different expression proteins of hepatic metastasis were correlated with lipid metabolism. For peritoneal metastasis, actin cytoskeleton regulation and glycolysis/gluconeogenesis could be enriched. ILK1 and CD14 were correlated with hepatic and peritoneal metastasis, respectively. Overexpression of CD14 and ILK1 impacted the colony formation ability of gastric cancer and increased expression of Vimentin. CD14 derived from immune cells in malignant ascites correlated with high activation of chemokine- and cytokine-mediated signaling pathways. In summary, biological functions of plasma exosome proteins among AGC patients with different metastatic modes were distinct, in which ILK1 and CD14 were correlated with organ-specific metastasis.

Construction and validation of a prognostic prediction model for gastric cancer using a series of genes related to lactate metabolism

Background

Gastric cancer (GC) is one of the most common clinical malignant tumors worldwide, with high morbidity and mortality. The commonly used tumor-node-metastasis (TNM) staging and some common biomarkers have a certain value in predicting the prognosis of GC patients, but they gradually fail to meet the clinical demands. Therefore, we aim to construct a prognostic prediction model for GC patients.

Methods

A total of 350 cases were included in the STAD (Stomach adenocarcinoma) entire cohort of TCGA (The Cancer Genome Atlas), including the STAD training cohort of TCGA (n = 176) and the STAD testing cohort of TCGA (n = 174). GSE15459 (n = 191), and GSE62254 (n = 300) were for external validation.

Results

Through differential expression analysis and univariate Cox regression analysis in the STAD training cohort of TCGA, we screened out five genes among 600 genes related to lactate metabolism for the construction of our prognostic prediction model. The internal and external validations showed the same result, that is, patients with higher risk score were associated with poor prognosis (all p < 0.05), and our model works well without regard of patients' age, gender, tumor grade, clinical stage or TNM stage, which supports the availability, validity and stability of our model. Gene function analysis, tumor-infiltrating immune cells analysis, tumor microenvironment analysis and clinical treatment exploration were performed to improve the practicability of the model, and hope to provide a new basis for more in-depth study of the molecular mechanism for GC and for clinicians to formulate more reasonable and individualized treatment plans.

Conclusions

We screened out and used five genes related to lactate metabolism to develop a prognostic prediction model for GC patients. The prediction performance of the model is confirmed by a series of bioinformatics and statistical analysis.

Pyrolyzed deketene curcumin controls regulatory T cell generation and gastric cancer metabolism cooperate with 2-deoxy-d-glucose

Pyrolyzed deketene curcumin GO-Y022 prevents carcinogenesis in a gastric cancer mouse model. However, it is still less clear if GO-Y022 affects tumor-induced immune suppression. In this study, we found that GO-Y022 inhibited Treg generation in the presence of transforming growth factor beta 1 (TGF-β). However, GO-Y022 showed less impact on Foxp3+ Tregs in the gastric tumor microenvironment. Gastric tumor cells produce a large amount of L-lactate in the presence of GO-Y022 and diminish the inhibitory role of GO-Y022 against Treg generation in response to TGF-β. Therefore, naïve CD4+ T cells co-cultured with GO-Y022 treated gastric tumor cells increased Treg generation. GO-Y022-induced tumor cell death was further enhanced by 2-deoxy-d-glucose (2DG), a glycolysis inhibitor. Combination treatment of GO-Y022 and 2DG results in reduced L-lactate production and Treg generation in gastric tumor cells. Overall, GO-Y022-treatment with restricted glucose metabolism inhibits gastric tumor cell survival and promotes anti-tumor immunity.

Potential of Copper and Copper Compounds for Anticancer Applications

Inducing cancer cell death has always been a research hotspot in life sciences. With the continuous deepening and diversification of related research, the potential value of metal elements in inducing cell death has been explored. Taking iron as an example, ferroptosis, mainly characterized by increasing iron load and driving the production of large amounts of lipid peroxides and eventually leading to cell death, has recently attracted great interest in the cancer research community. After iron, copper, a trace element, has received extensive attention in cell death, especially in inducing tumor cell death. Copper and its complexes can induce autophagy or apoptosis in tumor cells through a variety of different mechanisms of action (activation of stress pathways, arrest of cell cycle, inhibition of angiogenesis, cuproptosis, and paraptosis), which are promising in cancer therapy and have become new hotspots in cancer treatment research. This article reviews the main mechanisms and potential applications of novel copper and copper compound-induced cell death, focusing on copper compounds and their anticancer applications.

Posttranslational Modifications of Rev-Erbα Protein and Abnormal Inflammatory Response in Gastric Cancer

We reported that Rev-erbα, a transcriptional repressor, is reduced in human gastric cancer and that it inhibits glycolysis in cultured gastric cancer cells. However, it is unclear whether Rev-erbα undergoes posttranslational modifications in gastric cancer. Here, we determined levels of Rev-erbα and its posttranslational modifications including phosphorylation, SUMOylation, and ubiquitination in N-methyl-N-nitrosourea (MNU)/Helicobacter pylori (H. pylori)-induced gastric cancer in mice and in cultured human gastric cancer cells. Administration of MNU plus H. pylori infection successfully induced gastric tumor in C57BL/6J mice. MNU/H. pylori decreased the levels of Rev-erbα in gastric tumor tissues of mice accompanied by an increase in the level of lactic acid. Rev-erbα protein SUMOylation and ubiquitination modifications were significantly increased, whereas phosphorylation was unchanged, in gastric cancer cells line BGC-823 and MNU/H. pylori-induced mouse gastric cancer tissues. Using human gastric cancer tissues, we found that Rev-erbα was specifically reduced in mucosal epithelial cells in gastric tissue. Cytokine levels were increased in MNU/H. pylori-exposed mice compared with control mice. Similarly, the levels of IL-6 IL-10, TNF-α, and VEGF were higher in the BGC-823 cell line compared with GES-1 cells. IL-6 and IL-1 incubation did not affect Rev-erbα levels in BGC-823 cells. Furthermore, Rev-erbα was recruited on the promoters of these cytokine genes, which suppressed their expression. Conclusively, Rev-erbα SUMOylation and subsequent ubiquitination may contribute to its protein reduction, which leads to increased glycolysis and abnormal inflammatory responses during the development of gastric cancer. Targeting Rev-erbα and its SUMOylation represents promising approaches for prevention and management of gastric cancer.

Metabolism-associated molecular classification of gastric adenocarcinoma

Most gastric cancers (GC) are adenocarcinomas, whereas GC is a highly heterogeneous disease due to its molecular heterogeneity. However, traditional morphology-based classification systems, including the WHO classification and Lauren’s classification, have limited utility in guiding clinical treatment. We performed nonnegative matrix factorization (NMF) clustering based on 2752 metabolism-associated genes. We characterized each of the subclasses from multiple angles, including subclass-associated metabolism signatures, immune cell infiltration, clinic10al characteristics, drug sensitivity, and pathway enrichment. As a result, four subtypes were identified: immune suppressed, metabolic, mesenchymal/immune exhausted and hypermutated. The subtypes exhibited significant prognostic differences, which suggests that the metabolism-related classification has clinical significance. Metabolic and hypermutated subtypes have better overall survival, and the hypermutated subtype is likely to be sensitive to anti-PD-1 immunotherapy. In addition, our work showed a strong connection with previously established classifications, especially Lei’s subtype, to which we provided an interpretation based on the immune cell infiltration perspective, deepening the understanding of GC heterogeneity. Finally, a 120-gene classifier was generated to determine the GC classification, and a 10-gene prognostic model was developed for survival time prediction.

A Novel Glycolysis-Related Long Noncoding RNA Signature for Predicting Overall Survival in Gastric Cancer

Background: The aim of this study was to construct a glycolysis-related long noncoding RNA (lncRNA) signature to predict the prognosis of patients with gastric cancer (GC). Methods: Glycolysis-related genes were obtained from the Molecular Signatures Database (MSigDB), lncRNA expression profiles and clinical data of GC patients were obtained from The Cancer Genome Atlas database (TCGA). Furthermore, univariate Cox regression analysis, Least Absolute Shrinkage and Selection Operator (LASSO) and multivariate Cox regression analysis were used to construct prognostic glycolysis-related lncRNA signature. The specificity and sensitivity of the signature was verified by receiver operating characteristic (ROC) curves. We constructed a nomogram to predict the 1-year, 3-year, and 5-year survival rates of GC patients. Besides, the relationship between immune infiltration and the risk score was analyzed in the high and low risk groups. Multi Experiment Matrix (MEM) was used to analyze glycolysis-related lncRNA target genes. R "limma" package was used to analyze the mRNA expression levels of the glycolysis-related lncRNA target genes in TCGA. Gene set enrichment analysis (GSEA) was employed to further explore the biological pathways in the high-risk group and the glycolysis-related lncRNA target gene. Results: A prognostic signature was conducted based on nine glycolysis-related lncRNAs, which are AL391152.1, AL590705.3, RHOXF1-AS1, CFAP61-AS1, LINC00412, AC005165.1, AC110995.1, AL355574.1 and SCAT1. The area under the ROC curve (AUC) values at 1-year, 3-year, and 5-year were 0.765, 0.828 and 0.707 in the training set, and 0.669, 740 and 0.807 in the testing set, respectively. In addition, the nomogram could efficaciously predict the 1-year, 3-year, and 5-year survival rates of the GC patients. Then, we discovered that GC patients with high-risk scores were more likely to respond to immunotherapy. GSEA revealed that the signature was mainly associated with the calcium signaling pathway, extracellular matrix (ECM) receptor interaction, and focal adhesion in high-risk group, also indicated that SBSPON is related to aminoacyl-tRNA biosynthesis, citrate cycle, fructose and mannose metabolism, pentose phosphate pathway and pyrimidine metabolism. Conclusion: Our study shows that the signature can predict the prognosis of GC and may provide new insights into immunotherapeutic strategies.

Construction and validation of a glycolysis-related lncRNA signature for prognosis prediction in Stomach Adenocarcinoma

Background: Glycolysis is closely related to the occurrence and progression of gastric cancer (GC). Currently, there is no systematic study on using the glycolysis-related long non-coding RNA (lncRNA) as a model for predicting the survival time in patients with GC. Therefore, it was essential to develop a signature for predicting the survival based on glycolysis-related lncRNA in patients with GC. Materials and methods: LncRNA expression profiles, containing 375 stomach adenocarcinoma (STAD) samples, were obtained from The Cancer Genome Atlas (TCGA) database. The co-expression network of lncRNA and glycolysis-related genes was used to identify the glycolysis-related lncRNAs. The Kaplan-Meier survival analysis and univariate Cox regression analysis were used to detect the glycolysis-related lncRNA with prognostic significance. Then, Bayesian Lasso-logistic and multivariate Cox regression analyses were performed to screen the glycolysis-related lncRNA with independent prognostic significance and to develop the risk model. Patients were assigned into the low- and high-risk cohorts according to their risk scores. A nomogram model was constructed based on clinical information and risk scores. Gene Set Enrichment Analysis (GSEA) was performed to visualize the functional and pathway enrichment analyses of the glycolysis-related lncRNA. Finally, the robustness of the results obtained was verified in an internal validation data set. Results: Seven glycolysis-related lncRNAs (AL353804.1, AC010719.1, TNFRSF10A-AS1, AC005586.1, AL355574.1, AC009948.1, and AL161785.1) were obtained to construct a risk model for prognosis prediction in the STAD patients using Lasso regression and multivariate Cox regression analyses. The risk score was identified as an independent prognostic factor for the patients with STAD [HR = 1.315, 95% CI (1.056-1.130), p < 0.001] via multivariate Cox regression analysis. Receiver operating characteristic (ROC) curves were drawn and the area under curve (AUC) values of 1-, 3-, and 5-year overall survival (OS) were calculated to be 0.691, 0.717, and 0.723 respectively. Similar results were obtained in the validation data set. In addition, seven glycolysis-related lncRNAs were significantly enriched in the classical tumor processes and pathways including cell adhesion, positive regulation of vascular endothelial growth factor, leukocyte transendothelial migration, and JAK_STAT signaling pathway. Conclusion: The prognostic prediction model constructed using seven glycolysis-related lncRNA could be used to predict the prognosis in patients with STAD, which might help clinicians in the clinical treatment for STAD.

SP and KLF Transcription Factors in Cancer Metabolism

Tumor development and progression depend on reprogramming of signaling pathways that regulate cell metabolism. Alterations to various metabolic pathways such as glycolysis, oxidative phosphorylation, lipid metabolism, and hexosamine biosynthesis pathway are crucial to sustain increased redox, bioenergetic, and biosynthesis demands of a tumor cell. Transcription factors (oncogenes and tumor suppressors) play crucial roles in modulating these alterations, and their functions are tethered to major metabolic pathways under homeostatic conditions and disease initiation and advancement. Specificity proteins (SPs) and Krüppel-like factors (KLFs) are closely related transcription factors characterized by three highly conserved zinc fingers domains that interact with DNA. Studies have demonstrated that SP and KLF transcription factors are expressed in various tissues and regulate diverse processes such as proliferation, differentiation, apoptosis, inflammation, and tumorigenesis. This review highlights the role of SP and KLF transcription factors in the metabolism of various cancers and their impact on tumorigenesis. A better understanding of the role and underlying mechanisms governing the metabolic changes during tumorigenesis could provide new therapeutic opportunities for cancer treatment.

Assessment of cellular responses in three-dimensional cell cultures through chemical exchange saturation transfer and 1 H MRS

Metabolic responses to physiological changes have been detected using chemical exchange saturation transfer (CEST) imaging in clinical settings. Similarly to other MRI techniques, the CEST technique was based originally on phantoms from buffer solutions and was then further developed through animal experiments. However, CEST imaging can capture certain dynamics of metabolism that solution phantoms cannot model. Cell culture phantoms can fill the gap between buffer phantoms and animal models. In this study, we used ¹ H NMR and CEST in a B₀ field of 9.4 T to investigate HEK293T cells from two-dimensional (2D) cultures, three-dimensional (3D) cultures, and 3D cultures seeded with cell spheroids. Two CEST dips were observed: the magnitude of the amine dip at 2.8 ppm increased during the incubation period, whereas the hydroxyl dip at 1.2 ppm remained approximately the same or modestly increased. We also observed a CEST dip at 2.8 ppm from the 2D culture responding dramatically to doxorubicin treatment. By cross-validating with pH values and the concentrations of amine and hydroxyl protons extracted through ¹ H NMR, we observed that they did not correspond to an increase in the amine pool. We believe that the denaturation or degradation of proteins from the fetal bovine serum increased the size of the amine pool. Although 3D culture conditions can be further improved, our study suggests that 3D cultures have the potential to bridge studies of solution phantoms and those on animals.

Effects of Helicobacter pylori eradication on the profiles of blood metabolites and their associations with the progression of gastric lesions: a prospective follow-up study

Objective:

This study aimed at examining the alterations in metabolomic profiles caused by treatment of H. pylori infection, and the associations between key plasma metabolites and the risk of gastric lesion progression during follow-up after treatment.

Methods:

An intervention trial was performed in 183 participants, 117 of whom were H. pylori positive participants receiving treatment for H. pylori infection. H. pylori positive participants were prospectively followed for 182 to 1,289 days. Untargeted metabolomics assays were conducted on plasma samples collected at baseline, 6 months after treatment, and during continued follow-up.

Results:

We identified 59 metabolites with differential posttreatment changes between participants with successful and failed H. pylori eradication, 17 metabolites significantly distinguished participants with successful vs. failed eradication. Two metabolites [PC(18:1(11Z)/14:1(9Z)) and (2S)-6-amino-2-formamidohexanamide] showed posttreatment changes positively associated with successful H. pylori eradication, and were inversely associated with the risk of gastric lesion progression among participants with successful eradication. In contrast, 9-decenoic acid showed posttreatment changes inversely associated with successful eradication: its level was positively associated with the risk of gastric lesion progression among participants with successful eradication. Although the identified metabolites showed a temporary but significant decline after treatment, the trend generally reversed during continued follow-up, and pretreatment levels were restored.

Conclusions:

Treatment of H. pylori infection significantly altered plasma metabolic profiles in the short term, and key metabolites were capable of distinguishing participants with successful vs. failed eradication, but might not substantially affect metabolic regulation in the long term. Several plasma metabolites were differentially associated with the risk of gastric lesion progression among participants with successful or failed eradication.

Cancer metabolism control by natural products: Pyruvate kinase M2 targeting therapeutics

Glycolysis is the primary source of energy for cancer growth and metastasis. The shift in metabolism from mitochondrial oxidative phosphorylation to aerobic glycolysis is called the Warburg effect. Cancer progression due to aerobic glycolysis is often associated with the activation of oncogenes or the loss of tumor suppressors. Therefore, inhibition of glycolysis is one of the effective strategies in cancer control. Pyruvate kinase M2 (PKM2) is a key glycolytic enzyme overexpressed in breast, prostate, lung, colorectal, and liver cancers. Here, we discuss published studies regarding PKM2 inhibitors from natural products that are promising drug candidates for cancer therapy. We have highlighted the potential of natural PKM2 inhibitors for various cancer types. Moreover, we encourage researchers to evaluate the combinational effects between natural and synthetic PKM2 inhibitors. Also, further high-quality studies are needed to firmly establish the clinical efficacy of natural products.

Shikonin inhibited glycolysis and sensitized cisplatin treatment in non-small cell lung cancer cells via the exosomal pyruvate kinase M2 pathway

The active ingredient of the traditional Chinese medicine comfrey is shikonin, a naphthoquinone compound. The focus of this study was to investigate the effect of shikonin on the proliferation, invasion, migration, and chemoresistance of non-small cell lung cancer (NSCLC) cells, and to explore its underlying molecular biological mechanisms. The results show that shikonin inhibited the viability, proliferation, invasion, and migration of NSCLC cells A549 and PC9, and induced apoptosis. As the inhibitor of pyruvate kinase M2 (PKM2), a key enzyme in glycolysis, shikonin inhibited glucose uptake and the production of lactate, the final metabolite of aerobic glycolysis. In vivo chemotherapeutic assay showed that shikonin reduced the tumor volume and weight in NSCLC mice model and increased the sensitivity to cisplatin chemotherapy. Histoimmunology experiments showed the combination of shikonin and cisplatin downregulated the expression of PKM2 and its transcriptionally regulated downstream gene glucose transporter 1 (Glut1) in tumor tissue. In an assessment of glucose metabolism, micro-PET/CT data showed a combination of shikonin and cisplatin inhibited the fluorodeoxy glucose (¹⁸F-FDG) uptake into tumor. Since exosomal PKM2 affected the sensitivity to cisplatin in NSCLC cells, we also demonstrated shikonin could inhibit exosome secretion and exosomal PKM2 through the administration of exosomal inhibitor GW4869. Furthermore, shikonin sensitized cisplatin treatment by reducing the extracellular secretion of exosomal PKM2. In conclusion, we suggest that shikonin not only inhibits PKM2 intracellularly but also reduces glycolytic flux and increases cisplatin sensitivity through the exosomal pathway.

Impacts and mechanisms of metabolic reprogramming of tumor microenvironment for immunotherapy in gastric cancer

Metabolic disorders and abnormal immune function changes occur in tumor tissues and cells to varying degrees. There is increasing evidence that reprogrammed energy metabolism contributes to the development of tumor suppressive immune microenvironment and influences the course of gastric cancer (GC). Current studies have found that tumor microenvironment (TME) also has important clinicopathological significance in predicting prognosis and therapeutic efficacy. Novel approaches targeting TME therapy, such as immune checkpoint blockade (ICB), metabolic inhibitors and key enzymes of immune metabolism, have been involved in the treatment of GC. However, the interaction between GC cells metabolism and immune metabolism and how to make better use of these immunotherapy methods in the complex TME in GC are still being explored. Here, we discuss how metabolic reprogramming of GC cells and immune cells involved in GC immune responses modulate anti-tumor immune responses, as well as the effects of gastrointestinal flora in TME and GC. It is also proposed how to enhance anti-tumor immune response by understanding the targeted metabolism of these metabolic reprogramming to provide direction for the treatment and prognosis of GC.

Mechanism of N-Methyl-N-Nitroso-Urea-Induced Gastric Precancerous Lesions in Mice

Early diagnosis and treatment of gastric precancerous lesions (GPL) are key factors for reducing the incidence and morbidity of gastric cancer. The study is aimed at examining GPL in mice induced by N-methyl-N-nitroso-urea (MNU) and to illustrate the underlying mechanisms of tumorigenesis. In this study, we utilized an in vivo MNU-induced GPL mouse model, and histopathological changes of the gastric mucosa were observed by hematoxylin and eosin (H&E-stain) and alcian blue (AB-PAS-stain). The level of miR-194-5p in the gastric mucosa was determined by real-time polymerase chain reaction. We used transmission electron microscopy to observe the effects of MNU on gastric chief cells and parietal cells. We performed immunohistochemical detection of HIF-1α, vWF, Ki-67, and P53, while the changes in the protein expression of key genes in LKB1-AMPK and AKT-FoxO3 signaling pathways were detected by western blot analysis. We demonstrated that the miR-194-5p expression was upregulated under hypoxia in GPL gastric tissues, and that a high miR-194-5p expression level closely related with tumorigenesis. Mechanistically, miR-194-5p exerted the acceleration of activities related to metabolic reprogramming through LKB1-AMPK and AKT-FoxO3 pathways. Furthermore, similar to miR-194-5p, high expression levels of AMPK and AKT were also related to the metabolic reprogramming of GPL. Moreover, we revealed the correlation between the expression levels of miR-194-5p, p-AMPKα, p-AKT, and FoxO3a. These findings suggest that miR-194-5p/FoxO3 pathway is important for the reversal of metabolic reprogramming in GPL. Thus, exploring strategies to regulate the miR-194-5p/FoxO3a pathway may provide an efficient strategy for the prevention and treatment of GPL.

Targeting mitochondria as a therapeutic anti-gastric cancer approach

Gastric cancer is regarded as the fifth most common cancer globally but the third most common cancer death. Although systemic chemotherapy is the primary treatment for advanced gastric cancer patients, the outcome of chemotherapy is unsatisfactory. Novel therapeutic strategies and potential alternative treatments are therefore needed to overcome the impact of this disease. At a cellular level, mitochondria play an important role in cell survival and apoptosis. A growing body of studies have shown that mitochondria play a central role in the regulation of cellular function, metabolism, and cell death during carcinogenesis. Interestingly, the impact of mitochondrial dynamics, including fission/fusion and mitophagy, on carcinogenesis and cancer progression has also been reported, suggesting the potential targeting of mitochondrial dynamics for the treatment of cancer. This review not only comprehensively summarizes the homeostasis of gastric cancer cells, but the potential therapeutic interventions for the targeting of mitochondria for gastric cancer therapy are also highlighted and discussed.

PKM2 Is the Target of a Multi-Herb-Combined Decoction During the Inhibition of Gastric Cancer Progression

Gastric cancer is the third leading cause of cancer death worldwide. Traditional Chinese medicine (TCM) is increasingly extensively applied as a complementary therapy for gastric cancer (GC) in China, which shows unique advantages in preventing gastric cancer metastasis. Previous study indicates modified Jian-pi-yang-zheng (mJPYZ) decoction inhibit the progression of gastric cancer by regulating tumor-associated macrophages (TAM). However, it is unclear whether mJPYZ can affect metabolic reprogramming of gastric cancer cells. Here, we showed that mJPYZ effectively attenuated GC cells proliferation, migration and invasion. Meantime, mJPYZ reduced the aerobic glycolysis level of GC cells in vivo and in vitro by regulating the expression and nuclear translocation of PKM2. Overexpression of PKM2 that could reverse the inhibitory effect of mJPYZ, migration and epithelial to mesenchymal transition (EMT). Our results showed PKM2/HIF-1α signaling was the key metabolic regulator of mJPYZ in GC cells. In summary, our present study suggested that abnormal PKM2 is required for maintaining the malignant phenotype of GC cells. The TCM decoction mJPYZ inhibited GC cells growth and EMT by reducing of glycolysis in PKM2 dependent manner. This evidence expanded our understanding of the anti-tumor mechanism of mJPYZ and further indicated mJPYZ a potential anti-tumor agent for GC patients.

Identification of crucial genes of pyrimidine metabolism as biomarkers for gastric cancer prognosis

Background

Metabolic reprogramming has been reported in various kinds of cancers and is related to clinical prognosis, but the prognostic role of pyrimidine metabolism in gastric cancer (GC) remains unclear.

Methods

Here, we employed DEG analysis to detect the differentially expressed genes (DEGs) in pyrimidine metabolic signaling pathway and used univariate Cox analysis, Lasso-penalizes Cox regression analysis, Kaplan–Meier survival analysis, univariate and multivariate Cox regression analysis to explore their prognostic roles in GC. The DEGs were experimentally validated in GC cells and clinical samples by quantitative real-time PCR.

Results

Through DEG analysis, we found NT5E, DPYS and UPP1 these three genes are highly expressed in GC. This conclusion has also been verified in GC cells and clinical samples. A prognostic risk model was established according to these three DEGs by Univariate Cox analysis and Lasso-penalizes Cox regression analysis. Kaplan–Meier survival analysis suggested that patient cohorts with high risk score undertook a lower overall survival rate than those with low risk score. Stratified survival analysis, Univariate and multivariate Cox regression analysis of this model confirmed that it is a reliable and independent clinical factor. Therefore, we made nomograms to visually depict the survival rate of GC patients according to some important clinical factors including our risk model.

Conclusion

In a word, our research found that pyrimidine metabolism is dysregulated in GC and established a prognostic model of GC based on genes differentially expressed in pyrimidine metabolism.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02385-x.

Centromere protein U (CENPU) promotes gastric cancer cell proliferation and glycolysis by regulating high mobility group box 2 (HMGB2)

Gastric cancer is one of the most common malignancy with a leading mortality rate worldwide. Despite the progress in the diagnosis and therapeutic strategy, the associated mortality is still growing. It is of great significance to understand molecular mechanisms of the development of gastric cancer. Glycolysis is a main source of ATP provision for cancer cells including gastric cancer, and targeting glycolysis is a promising therapeutic strategy. Centromere protein U (CENPU) has been found to be overexpressed in many types of cancer. Downregulation of CENPU suppresses the proliferation and invasion of cancer cells. High mobility group box 2 (HMGB2) is identified as a biomarker to diagnose of gastric cancer. Knockdown of HMGB2 inhibits proliferation and glycolysis in gastric cancer cells. In this work, we identified that CENPU was upregulated in gastric cancer. Knockdown of CENPU was able to suppress the proliferation and glycolysis of gastric cancer cells. Further the results showed that the anti-cancer effect of CENPU was HMGB2-dependent. Taken together, CENPU is an upstream factor of HMGB2, which regulates proliferation and glycolysis of gastric cancer.

Tubular Cell Glucose Metabolism Shift During Acute and Chronic Injuries

Acute and chronic kidney disease are responsible for large healthcare costs worldwide. During injury, kidney metabolism undergoes profound modifications in order to adapt to oxygen and nutrient shortage. Several studies highlighted recently the importance of these metabolic adaptations in acute as well as in chronic phases of renal disease, with a potential deleterious effect on fibrosis progression. Until recently, glucose metabolism in the kidney has been poorly studied, even though the kidney has the capacity to use and produce glucose, depending on the segment of the nephron. During physiology, renal proximal tubular cells use the beta-oxidation of fatty acid to generate large amounts of energy, and can also produce glucose through gluconeogenesis. In acute kidney injury, proximal tubular cells metabolism undergo a metabolic shift, shifting away from beta-oxidation of fatty acids and gluconeogenesis toward glycolysis. In chronic kidney disease, the loss of fatty acid oxidation is also well-described, and data about glucose metabolism are emerging. We here review the modifications of proximal tubular cells glucose metabolism during acute and chronic kidney disease and their potential consequences, as well as the potential therapeutic implications.

Contribution of upregulated aminoacyl-tRNA biosynthesis to metabolic dysregulation in gastric cancer

BACKGROUND AND AIM

Metabolic reprogramming is characterized by dysregulated levels of metabolites and metabolic enzymes. Integrated metabolomic and transcriptomic data analysis can help to elucidate changes in the levels of metabolites and metabolic enzymes, screen the core metabolic pathways, and develop novel therapeutic strategies for cancer.

METHODS

Here, the metabolome of gastric cancer tissues was determined using liquid chromatography-mass spectrometry. The transcriptome data from The Cancer Genome Atlas dataset were integrated with the liquid chromatography-mass spectrometry data to identify the common dysregulated gastric cancer-specific metabolic pathways. Additionally, the protein expression and clinical significance of key metabolic enzymes were examined using a gastric cancer tissue array.

RESULTS

Metabolomic analysis of 16 gastric cancer tissues revealed that among the 15 dysregulated metabolomic pathways, the aminoacyl-tRNA biosynthesis pathway in the gastric tissues was markedly upregulated relative to that in the adjacent noncancerous tissues, which was consistent with the results of transcriptome analysis. Bioinformatic analysis revealed that among the key regulators in the aminoacyl-tRNA biosynthesis pathway, the expression levels of threonyl-tRNA synthetase (TARS) and phenylalanyl-tRNA synthetase (FARSB) were correlated with tumor grade and poor survival, respectively. Additionally, gastric tissue array data analysis indicated that TARS and FARSB were upregulated in gastric cancer tissues and were correlated with poor prognosis and tumor metastasis.

CONCLUSIONS

This study demonstrated that the aminoacyl-tRNA biosynthesis pathway is upregulated in gastric cancer and both TARS and FARSB play key roles in the progression of gastric cancer. Additionally, a novel therapeutic strategy for gastric cancer was proposed that involves targeting the aminoacyl-tRNA biosynthesis pathway.

Long noncoding RNA HAGLR sponges miR-338-3p to promote 5-Fu resistance in gastric cancer through targeting the LDHA-glycolysis pathway

Gastric cancer (GC) is one of the most common human malignancies due to its invasiveness and metastasis. 5‐Fu is a widely applied chemotherapeutic agent against GC. Although 5‐Fu therapy has achieved improvements in GC treatment, a large fraction of patients developed drug resistance which significantly limited its clinical applications. Recent studies revealed the pivotal roles of long noncoding RNAs (lncRNAs) in tumorigenesis and progressions of various tumors, including GC. However, the biological roles and molecular mechanisms of lncRNA HAGLR in GC remain unclear. Here, we report HAGLR was upregulated in both GC tissues and cell lines. In addition, HAGLR was associated with a poorly survival rate of GC patients. Blocking HAGLR inhibited GC cells proliferation and sensitized GC cells to 5‐Fu. Bioinformatical analysis and luciferase assay demonstrated that HAGLR sponged microRNA (miR)‐338‐3p, which functions as a tumor suppressor in GC to downregulate its expressions. Moreover, from the established 5‐Fu resistant GC cell line (HGC27 5‐Fu R), we detected significantly elevated HAGLR, downregulated miR‐338‐3p, and glucose metabolism compared with parental HGC27 cells. We identified lactate dehydrogenase‐A (LDHA), a glucose metabolism key enzyme, was the direct target of miR‐338‐3p in GC cells. Rescue experiments demonstrated that restoration of miR‐338‐3p in HAGLR‐overexpressing HGC27 5‐Fu R cells successfully overrode the HAGLR‐promoted 5‐Fu resistance through targeting LDHA. Taken together, this study revealed essential roles and molecular mechanisms for the HAGLR‐mediated 5‐Fu resistance in GC, contributing to the development of new noncoding RNA‐based therapeutic strategies against chemoresistant GC.

The Mechanism of Warburg Effect-Induced Chemoresistance in Cancer

Although chemotherapy can improve the overall survival and prognosis of cancer patients, chemoresistance remains an obstacle due to the diversity, heterogeneity, and adaptability to environmental alters in clinic. To determine more possibilities for cancer therapy, recent studies have begun to explore changes in the metabolism, especially glycolysis. The Warburg effect is a hallmark of cancer that refers to the preference of cancer cells to metabolize glucose anaerobically rather than aerobically, even under normoxia, which contributes to chemoresistance. However, the association between glycolysis and chemoresistance and molecular mechanisms of glycolysis-induced chemoresistance remains unclear. This review describes the mechanism of glycolysis-induced chemoresistance from the aspects of glycolysis process, signaling pathways, tumor microenvironment, and their interactions. The understanding of how glycolysis induces chemoresistance may provide new molecular targets and concepts for cancer therapy.

Glycosaminoglycan biosynthesis pathway in host genome is associated with Helicobacter pylori infection

Helicobacter pylori is a causative pathogen of many gastric and extra-gastric diseases. It has infected about half of the global population. There were no genome-wide association studies (GWAS) for H. pylori infection conducted in Chinese population, who carried different and relatively homogenous strain of H. pylori. In this work, we performed SNP (single nucleotide polymorphism)-based, gene-based and pathway-based genome-wide association analyses to investigate the genetic basis of host susceptibility to H. pylori infection in 480 Chinese individuals. We also profiled the composition and function of the gut microbiota between H. pylori infection cases and controls. We found several genes and pathways associated with H. pylori infection (P < 0.05), replicated one previously reported SNP rs10004195 in TLR1 gene region (P = 0.02). We also found that glycosaminoglycan biosynthesis related pathway was associated with both onset and progression of H. pylori infection. In the gut microbiome association study, we identified 2 species, 3 genera and several pathways had differential abundance between H. pylori infected cases and controls. This paper is the first GWAS for H. pylori infection in Chinese population, and we combined the genetic and microbial data to comprehensively discuss the basis of host susceptibility to H. pylori infection.

Identification and validation of a novel glycolysis-related gene signature for predicting the prognosis in ovarian cancer

Background

Ovarian cancer (OC) is the most lethal gynaecological tumor. Changes in glycolysis have been proven to play an important role in OC progression. We aimed to identify a novel glycolysis-related gene signature to better predict the prognosis of patients with OC.

Methods

mRNA and clinical data were obtained from The Cancer Genome Atlas (TCGA), International Cancer Genome Consortium (ICGC) and Genotype Tissue Expression (GTEx) database. The “limma” R package was used to identify glycolysis-related differentially expressed genes (DEGs). Then, a multivariate Cox proportional regression model and survival analysis were used to develop a glycolysis-related gene signature. Furthermore, the TCGA training set was divided into two internal test sets for validation, while the ICGC dataset was used as an external test set. A nomogram was constructed in the training set, and the relative proportions of 22 types of tumor-infiltrating immune cells were evaluated using the “CIBERSORT” R package. The enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were determined by single-sample gene set enrichment analysis (ssGSEA) with the “GSVA” R package. Finally, the expression and function of the unreported signature genes ISG20 and SEH1L were explored using immunohistochemistry, western blotting, qRT-PCR, proliferation, migration, invasion and xenograft tumor assays.

Results

A five-gene signature comprising ANGPTL4, PYGB, ISG20, SEH1L and IRS2 was constructed. This signature could predict prognosis independent of clinical factors. A nomogram incorporating the signature and three clinical features was constructed, and the calibration plot suggested that the nomogram could accurately predict the survival rate. According to ssGSEA, the signature was associated with KEGG pathways related to axon guidance, mTOR signalling, tight junctions, etc. The proportions of tumor-infiltrating immune cells differed significantly between the high-risk group and the low-risk group. The expression levels of ISG20 and SEH1L were lower in tumor tissues than in normal tissues. Overexpression of ISG20 or SEH1L suppressed the proliferation, migration and invasion of Caov3 cells in vitro and the growth of xenograft tumors in vivo.

Conclusion

Five glycolysis-related genes were identified and incorporated into a novel risk signature that can effectively assess the prognosis and guide the treatment of OC patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02045-0.

A Potential Oncogenic Role for PFKFB3 Overexpression in Gastric Cancer Progression

OBJECTIVES

PFKFB3 regulates glycolysis in tumor cells, might function as an oncogene, and is associated with cancer metastasis. However, its role in gastric cancer (GC) remains largely unknown.

METHODS

PFKFB3 expression was assessed by immunohistochemistry (IHC) in GC tissues and paired paracancerous histological normal tissues (PCHNTs). The associations of PFKFB3 expression with clinical features and HIF-1α, Ki-67, E-cadherin, Snail, and Vimentin expression levels were assessed. A series of in vivo and in vitro experiments were performed to investigate the effects of PFKFB3 on the growth, migration, and invasion of GC cells.

RESULTS

We found that PFKFB3 expression was significantly higher in GC tissues compared with PCHNTs (P = 0.000). PFKFB3 expression was positively correlated with tumor size (P = 0.000), differentiation (P = 0.025), venous invasion (P = 0.084), nerve invasion (P = 0.014), lymphatic invasion (P = 0.000), local invasion (P = 0.000), invasive depth (P = 0.000), nodal metastasis (P = 0.000), tumor-node-metastasis stage (P = 0.000), and patient survival (P = 0.000). Notably, PFKFB3 upregulation was highly correlated with increased epithelial-mesenchymal transition (EMT) in GC samples. PFKFB3 overexpression positively modulated cell proliferation, migration, and EMT in GC cells in vitro, with concomitant activation of NF-κB signaling. Administration of an NF-κB inhibitor attenuated PFKFB3-induced EMT in GC cells. PFKFB3 overexpression promoted tumor development and EMT in nude mice, which were attenuated by PFK-15, a PFKFB3 inhibitor.

DISCUSSION

PFKFB3 could potentiate malignancy in GC cells through NF-κB pathway-mediated EMT, suggesting PFKFB3 represents a potential target for GC therapy.

Mortalin/glucose-regulated protein 75 promotes the cisplatin-resistance of gastric cancer via regulating anti-oxidation/apoptosis and metabolic reprogramming

Platinum drug treatment is one of the most predominant chemotherapeutic strategies for patients with gastric cancer (GC). However, the therapeutic effect is less than satisfactory, largely due to the acquired resistance to platinum drugs. Therefore, a better understanding of the underlying mechanisms can greatly improve the therapeutic efficacy of GC. In this study, we aimed to investigate the chemo-resistance related functions/mechanisms and clinical significance of glucose-regulated protein 75 (GRP75) in GC. Here, our data showed that compared with SGC7901 cells, the expression of GRP75 was markedly higher in cisplatin-resistance cells (SGC7901^CR). Knockdown of GRP75 abolished the maintenance of mitochondrial membrane potential (MMP) and inhibited the nuclear factor erythroid-2-related factor 2 (NRF2), phosphatidylinositol 3 kinase/protein kinase B (PI3K/AKT), hypoxia-inducible factor 1α (HIF-1α), and c-myc, which resulted in blocking the activation of their downstream targets. These processes attenuated the anti-oxidation/apoptosis abilities and altered the metabolic reprogramming in SGC7901^CR cells, leading to re-sensitizing these cells to cisplatin. However, overexpression of GRP75 in SGC7901 cells caused the opposite effects. A xenografts model confirmed the abovementioned results. In GC patients receiving platinum chemotherapy and a meta-analysis, a high level of GRP75 was positively associated with aggressive characteristics and poor prognosis including but not limited to gastrointestinal cancers, and was an independent predictor for overall survival. Collectively, our study indicated that GRP75 was involved in the cisplatin-resistance of GC and that GRP75 could be a potential therapeutic target for restoring the drug response in platinum-resistance cells and a useful additive prognostic tool in guiding clinical management of GC patients.

Knockdown of ZNF479 inhibits proliferation and glycolysis of gastric cancer cells through regulating β-catenin/c-Myc signaling pathway

Gastric cancer is the fifth most common malignancy and the third most deadly tumor in the world. Zinc finger protein 479 (ZNF479) has been demonstrated to play crucial roles in hepatocellular carcinoma. However, the function of ZNF479 in gastric cancer remains to be clarified. The current study aimed to investigate the role of ZNF479 in gastric cancer progression and elucidate the potential molecular mechanism. In this study, Cell Count Kit-8 and colony formation assays demonstrated that knockdown of ZNF479 inhibited cell proliferation in AGS and SGC-7901 cells. Of note, knockdown of ZNF479 hinders tumor growth of xenograft tumor mice. What is more, knockdown of ZNF479 inhibited glucose uptake, lactate production, adenosine triphosphate level, and extracellular acidification ratio; increased oxygen consumption ratio in gastric cancer cells; and decreased the expression of glycolytic proteins both in vitro and in vivo. Furthermore, analysis mechanism suggests that ZNF479 participated in the regulation of gastric cancer progression through affecting the β-catenin/c-Myc signaling pathway. Collectively, ZNF479 plays a role as an oncogene through modulating β-catenin/c-Myc signaling pathway in the development of gastric cancer, which provides a new research target for future studies.

Metabolomics of Gastric Cancer

Gastric cancer is the fourth most common malignancy worldwide and the third leading cause of cancer deaths. Recent metabolomics research has advanced our understanding of the relationship between metabolic reprogramming and gastric cancer progression and led to the discovery of metabolic targets for potential clinical applications and therapeutic interventions. As a powerful tool for metabolite and flux measurement, metabolomics not only allows a comprehensive analysis of metabolites and related metabolic pathways but also can investigate the interactions between gastric cancer cells and tumour microenvironment as well as between the cancer cells and gastric microbiome. In this chapter, we aim to summarize the recent advances in gastric cancer metabolism and discuss the applications of metabolomics for target discovery in gastric cancer.

Rabeprazole suppresses cell proliferation in gastric epithelial cells by targeting STAT3-mediated glycolysis

The dysregulation of glycolysis leads to serials of disease. Rabeprazole is a representative of proton pump inhibitors and widely used in anti-ulcer treatment. However, the function of Rabeprazole on glycolysis in gastric epithelial cells remained to be identified. In this study, 30（Helicobacter pylori）H. pylori-negative cases and 26H. pylori-positive cases treated with Rabeprazole were recruited. The qPCR and Western blotting results showed that Rabeprazole suppressed cell proliferation by inhibition of HK2-mediated glycolysis in BGC823 cells, leading to decrease glucose uptake and lactate production in a dose-dependent way. Furthermore, the phosphorylation of signal transducer and activator of transcription 3 (STAT3) was drastically reduced in response to Rabeprazole stimulation, leading to attenuate STAT3 nuclear translocation. Luciferase and Chromatin immunoprecipitation (ChIP) analysis showed that Rabeprazole treatment led to a significant inhibition of the binding of STAT3 to the promoter of the HK2 gene, repressing transcriptional activation of HK2. Moreover, the ectopic expression of STAT3 in BGC823 cells resulted in recovery of HK2 transactivation and cell proliferation in Rabeprazole-treated cells. Most importantly, HK2 expression was significantly increased in H. pylori-infected gastric mucosa. These findings suggested that Rabeprazole inhibited cell proliferation by targeting STAT3/HK2 signaling-mediated glucose metabolism in gastric epithelial cells. Therefore, targeting HK2 is an alternative strategy in improving the treatment of patients with H. pylori infection.

Effects of the Novel PFKFB3 Inhibitor KAN0438757 on Colorectal Cancer Cells and Its Systemic Toxicity Evaluation In Vivo

BACKGROUND

Despite substantial progress made in the last decades in colorectal cancer (CRC) research, new treatment approaches are still needed to improve patients' long-term survival. To date, the promising strategy to target tumor angiogenesis metabolically together with a sensitization of CRC to chemo- and/or radiotherapy by PFKFB3 (6-phosphofructo-2-kinase/fructose-2,6-biphosphatase-3) inhibition has never been tested. Therefore, initial evaluation and validation of newly developed compounds such as KAN0438757 and their effects on CRC cells are crucial steps preceding to in vivo preclinical studies, which in turn may consolidate new therapeutic targets.

MATERIALS AND METHODS

The efficiency of KAN0438757 to block PFKFB3 expression and translation in human CRC cells was evaluated by immunoblotting and real-time PCR. Functional in vitro assays assessed the effects of KAN0438757 on cell viability, proliferation, survival, adhesion, migration and invasion. Additionally, we evaluated the effects of KAN0438757 on matched patient-derived normal and tumor organoids and its systemic toxicity in vivo in C57BL6/N mice.

RESULTS

High PFKFB3 expression is correlated with a worse survival in CRC patients. KAN0438757 reduces PFKFB3 protein expression without affecting its transcriptional regulation. Additionally, a concentration-dependent anti-proliferative effect was observed. The migration and invasion capacity of cancer cells were significantly reduced, independent of the anti-proliferative effect. When treating colonic patient-derived organoids with KAN0438757 an impressive effect on tumor organoids growth was apparent, surprisingly sparing normal colonic organoids. No high-grade toxicity was observed in vivo.

CONCLUSION

The PFKFB3 inhibitor KAN0438757 significantly reduced CRC cell migration, invasion and survival. Moreover, on patient-derived cancer organoids KAN0438757 showed significant effects on growth, without being overly toxic in normal colon organoids and healthy mice. Our findings strongly encourage further translational studies to evaluate KAN0438757 in CRC therapy.

The sepsis induced defective aggravation of immune cells: a translational science underling chemico-biological interactions from altered bioenergetics and/or cellular metabolism to organ dysfunction

Sepsis is described as a systemic immune response of the body to an infectious process that might result in dysfunctional organs that may lead to death. In clinical practice, sepsis is considered a medical emergency. The initial event in sepsis caused by a deregulated host response towards harmful microorganisms that leads to an aggravated systemic inflammatory response syndrome (SIRS) to tackle with pathogen invasion and a compensatory anti-inflammatory response syndrome (CARS) that lasts for several days. The inflammatory response and the cellular damage as well as the risk of an organ dysfunction are in direct proportion. Even though, the pathogenesis of sepsis remains unclear, many studies have shown evidence of role of oxidants and antioxidants in sepsis. The altered innate and adaptive immune cell and upregulated production and release of cytokines and chemokines most probably due to involvement of JAK-STAT pathway, disturbance in redox homeostasis due to low clearance of lactate and other oxidative stressors, contributes to sepsis process to organ dysfunction which contribute to increase rates of mortality among these patients. Hence, the treatment strategies for sepsis include antibiotics, ventilator and blood glucose management and other strategies for resuscitation are rapidly progressing. In the current review, we mainly concentrate on throwing light on the main molecular aspects and chemico-biological interactions that shows involvement in pathways manipulating alteration in physiology of immune cells (innate and adaptive) that change the bioenergetics/cellular metabolism to organ dysfunction and correlation of these altered pathway, improve the understating for new therapeutic target for sepsis.

Pyruvate Kinase M2 Knockdown Suppresses Migration, Invasion, and Epithelial-Mesenchymal Transition of Gastric Carcinoma via Hypoxia-Inducible Factor Alpha/B-Cell Lymphoma 6 Pathway

Gastric carcinoma is a common malignant cancer. Pyruvate kinase M2 (PKM2) is highly expressed in cancers, including gastric carcinoma. However, its function and molecular mechanism in gastric carcinoma remains unclear. Here, we aimed to explore the function and the underlying mechanism of PKM2 on malignant phenotypes in gastric carcinoma. In this study, the mRNA levels and protein levels of PKM2 in gastric carcinoma cell lines and normal gastric mucosa epithelial cell lines were detected using quantitative real-time PCR and western blot, respectively. PKM2 was downregulated by siRNA transfection. HIF-1α or BCL-6 was upregulated by corresponding overexpression plasmid. Cell viability was detected using CCK-8 assay. Cell invasion and migration were determined using transwell assay. Higher expression of PKM2 was observed in human gastric carcinoma cell lines MKN-45 and SGC-7901 than in the normal gastric mucosa epithelial cell line GES-1. PKM2 knockdown suppressed cancer cell invasion and migration and inhibited the epithelial-mesenchymal transition (EMT) phenotype by inhibiting E-cadherin and promoting vimentin and N-cadherin expression. Also, we observed that PKM2 knockdown suppressed the hypoxia-inducible factor alpha (HIF-1α) and B-cell lymphoma 6 (BCL-6) signaling pathway. HIF-1α overexpression reversed the function of PKM2 silencing on cell invasion, migration, EMT, and BCL-6 expression. BCL-6 overexpression also reversed the function of PKM2 silencing on cell invasion, migration, and EMT but did not affect HIF-1α expression. Taken together, data from our study suggest that PKM2 knockdown impeded cell migration, invasion, and EMT of gastric carcinoma cells via the HIF-1α/BCL-6 pathway.

Ultra-sensitive and selective electrochemical biosensor with aptamer recognition surface based on polymer quantum dots and C60/MWCNTs- polyethylenimine nanocomposites for analysis of thrombin protein

In this study, an ultra-sensitive and selective Thrombin biosensor with aptamer-recognition surface is introduced based on carbon nanocomposite. To prepare the this biosensor, screen-printed carbon electrodes (SPCE) were modified with a nanocomposite made from fullerene (C₆₀), multi-walled carbon nanotubes (MWCNTs), polyethylenimine (PEI) and polymer quantum dots (PQdot). The unique characteristics of each component of the C₆₀/MWCNTs-PEI/PQdot nanocomposite allow for synergy between nanoparticles while polymer quantum dots resulted in characteristics such as high stability, high surface to volume ratio, high electrical conductivity, high biocompatibility, and high mechanical and chemical stability. The large number of amine groups in C₆₀/MWCNTs-PEI/PQdot nanocomposite created more sites for better covalent immobilization of amino-linked aptamer (APT) which improved the sensitivity and stability of the aptasensor. Differential Pulse Voltammetry (DPV) method with probe solution was used as the measurment method. Binding of thrombin protein to aptamers immobilized on the transducer resulted in reduced electron transfer at the electrode/electrolyte interface which reduces the peak current (I_P) in DPV. The calibration curve was drawn using the changes in the peak current (ΔI_P),. The proposed aptasensor has a very low detection limit of 6 fmol L^-1, and a large linear range of 50 fmol L^-1 to 20 nmol L^-1. Furthermore, the proposed C₆₀/MWCNTs-PEI/PQdot/APT aptasensor has good reproducibility, great selectivity, low response time and a good stability during its storage. Finally, the application of the proposed aptasensor for measuring thrombin on human blood serum samples was investigated. This aptasensor can be useful in bioengineering and biomedicine applications as well as for clinical studies.

Extracellular Citrate Is a Trojan Horse for Cancer Cells

The first intermediate in the mitochondrial tricarboxylic acid (TCA) cycle is citrate, which is essential and acts as a metabolic regulator for glycolysis, TCA cycle, gluconeogenesis, and fatty acid synthesis. Within the cytosol, citrate is cleaved by ATP citrate lyase (ACLY) into oxaloacetate (OAA) and acetyl-CoA; OAA can be used for neoglucogenesis or in the TCA cycle, while acetyl-CoA is the precursor of some biosynthetic processes, including the synthesis of fatty acids. Accumulating evidence suggests that citrate is involved in numerous physiological and pathophysiological processes such as inflammation, insulin secretion, neurological disorders, and cancer. Considering the crucial role of citrate to supply the acetyl-CoA pool for fatty acid synthesis and histone acetylation in tumors, in this study we evaluated the effect of citrate added to the growth medium on lipid deposition and histone H4 acetylation in hepatoma cells (HepG2). At low concentration, citrate increased both histone H4 acetylation and lipid deposition; at high concentration, citrate inhibited both, thus suggesting a crucial role of acetyl-CoA availability, which prompted us to investigate the effect of citrate on ACLY. In HepG2 cells, the expression of ACLY is correlated with histone acetylation, which, in turn, depends on citrate concentration. A decrease in H4 acetylation was also observed when citrate was added at a high concentration to immortalized human hepatic cells, whereas ACLY expression was unaffected, indicating a lack of control by histone acetylation. Considering the strong demand for acetyl-CoA but not for OAA in tumor cells, the exogenous citrate would behave like a trojan horse that carries OAA inside the cells and reduces ACLY expression and cellular metabolism. In addition, this study confirmed the already reported dual role of citrate both as a promoter of cell proliferation (at lower concentrations) and as an anticancer agent (at higher concentrations), providing useful tips on the use of citrate for the treatment of tumors.

Development and Validation of a Scoring System Based on 9 Glycolysis-Related Genes for Prognosis Prediction in Gastric Cancer

Gastric cancer is a malignant tumor with high morbidity and mortality worldwide. However, increasing evidences have revealed the correlation between the glycolysis process and tumorigenesis. This study is aim to develop a list of glycolysis-related genes for risk stratification in gastric cancer patients. We included 500 patients’ sample data from GSE62254 and GSE26942 datasets, and classified patients into training (n = 350) and testing sets (n = 150) at a ratio of 7: 3. Univariate and multivariate Cox regression analysis were performed to screen genes having prognostic value. Based on HALLMARK gene sets, we identified 9 glycolysis-related genes (BPNT1, DCN, FUT8, GMPPA, GPC3, LDHC, ME2, PLOD2, and UGP2). On the basis of risk score developed by the 9 genes, patients were classified into high- and low-risk groups. The survival analysis showed that the high-risk patients had a worse prognosis (p < 0.001). Similar finding was observed in the testing cohort and 2 independent cohorts (GSE13861 and TCGA-STAD, all p < 0.001). The multivariate Cox regression analysis showed that the risk score was an independent prognostic factor for overall survival (p < 0.001). Furthermore, we constructed a nomogram that integrated the risk score and tumor stage, age, and adjuvant chemotherapy. Through comparing the results of the receiver operating characteristic curves and decision curve analysis, we found that the nomogram had a superior predictive accuracy than conventional TNM staging system, suggesting that the risk score combined with other clinical factors (age, tumor stage, and adjuvant chemotherapy) can develop a robust prediction for survival and improve the individualized clinical decision making of the patient.

In conclusion, we identified 9 glycolysis-related genes from hallmark glycolysis pathway. Based on the 9 genes, gastric cancer patients were separated into different risk groups related to survival.

Glycolytic competence in gastric adenocarcinomas negatively impacts survival outcomes of patients treated with salvage paclitaxel-ramucirumab

INTRODUCTION

For energy production, cancer cells maintain a high rate of glycolysis instead of oxidative phosphorylation converting glucose into lactic acid. This metabolic shift is useful to survive in unfavorable microenvironments. We investigated whether a positive glycolytic profile (PGP) in gastric adenocarcinomas may be associated with unfavorable outcomes under an anticancer systemic therapy, including the anti-angiogenic ramucirumab.

MATERIALS AND METHODS

Normal mucosa (NM) and primary tumor (PT) of 40 metastatic gastric adenocarcinomas patients who received second-line paclitaxel-ramucirumab (PR) were analyzed for mRNA expression of the following genes: HK-1, HK-2, PKM-2, LDH-A, and GLUT-1. Patients were categorized with PGP when at least a doubling of mRNA expression (PT vs. NM) in all glycolytic core enzymes (HK-1 or HK-2, PKM-2, LDH-A) was observed. PGP was also related to TP53 mutational status.

RESULTS

Mean LDH-A, HK-2, PKM-2 mRNA expression levels were significantly higher in PT compared with NM. 18 patients were classified as PGP, which was associated with significantly worse progression-free and overall survival times. No significant association was observed between PGP and clinical-pathologic features, including TP53 positive mutational status, in 28 samples.

CONCLUSIONS

Glycolytic proficiency may negatively affect survival outcomes of metastatic gastric cancer patients treated with PR systemic therapy. TP53 mutational status alone does not seem to explain such a metabolic shift.

Melatonin: A Potential Therapeutic Option for Breast Cancer

Melatonin has significant inhibitory effects in numerous cancers, especially breast cancer. In estrogen receptor (ER)-positive human breast cancer, the oncostatic actions of melatonin are mainly achieved by suppressing ER mRNA expression and ER transcriptional activity via the MT1 receptor. Melatonin also regulates the transactivation of nuclear receptors, estrogen-metabolizing enzymes, and the expression of related genes. Furthermore, melatonin suppresses tumor aerobic glycolysis, critical cell-signaling pathways relevant to cell proliferation, survival, metastasis, and overcomes drug resistance. Studies in animal and human models indicate that disruption of the circadian nocturnal melatonin signal promotes the growth, metabolism, and signaling of human breast cancer, resulting in resistance to hormone therapy and chemotherapy, which may be reversed by melatonin.

The Double-Edge Sword of Autophagy in Cancer: From Tumor Suppression to Pro-tumor Activity

During tumorigenesis, cancer cells are exposed to a wide variety of intrinsic and extrinsic stresses that challenge homeostasis and growth. Cancer cells display activation of distinct mechanisms for adaptation and growth even in the presence of stress. Autophagy is a catabolic mechanism that aides in the degradation of damaged intracellular material and metabolite recycling. This activity helps meet metabolic needs during nutrient deprivation, genotoxic stress, growth factor withdrawal and hypoxia. However, autophagy plays a paradoxical role in tumorigenesis, depending on the stage of tumor development. Early in tumorigenesis, autophagy is a tumor suppressor via degradation of potentially oncogenic molecules. However, in advanced stages, autophagy promotes the survival of tumor cells by ameliorating stress in the microenvironment. These roles of autophagy are intricate due to their interconnection with other distinct cellular pathways. In this review, we present a broad view of the participation of autophagy in distinct phases of tumor development. Moreover, autophagy participation in important cellular processes such as cell death, metabolic reprogramming, metastasis, immune evasion and treatment resistance that all contribute to tumor development, is reviewed. Finally, the contribution of the hypoxic and nutrient deficient tumor microenvironment in regulation of autophagy and these hallmarks for the development of more aggressive tumors is discussed.