Energy deregulation: licensing tumors to grow

Phosphorylation of FOXK2 at Thr13 and Ser30 by PDK2 sustains glycolysis through a positive feedback manner in ovarian cancer

Ovarian cancer is one of the most common gynecological malignant tumors with insidious onset, strong invasiveness, and poor prognosis. Metabolic alteration, particularly aerobic glycolysis, which is tightly regulated by transcription factors, is associated with the malignant behavior of OC. We screened FOXK2 in this study as a key transcription factor that regulates glycolysis in OC. FOXK2 is overly expressed in OC, and poor prognosis is predicted by overexpression. FOXK2 promotes OC cell proliferation both in vitro and in vivo and cell migration in vitro. Further studies showed that PDK2 directly binds to the forkhead-associated (FHA) domain of FOXK2 to phosphorylate FOXK2 at Thr13 and Ser30, thereby enhancing the transcriptional activity of FOXK2. FOXK2 transcriptionally regulates the expression of PDK2, thus forming positive feedback to sustain glycolysis in OC cells.

Identification of ALDOB as a novel prognostic biomarker in kidney clear cell renal cell carcinoma

Kidney clear cell renal cell carcinoma (KIRC) is also the most lethal subtype among all kidney cancer subtypes, posing a severe threat to public health. Therefore, it is crucial to identify new, reliable biomarkers in KIRC. Therefore, it is crucial to identify novel, reliable biomarkers associated with KIRC. We analyzed RNA sequence results from TCGA and several GEO datasets. The commonly deregulated gene, ALDOB, was found in multiple data and confirmed its important prognostic value. Subsequently, we explored the specific mechanism by which ALDOB regulates anti-tumor immunity through in vivo and in vitro experiments. We found that ALDOB may play a role in regulating tumor growth by regulating CD8+ T cell infiltration. This is consistent with the results of our immune infiltration-related analysis. In addition, we have also discovered the effect of ALDOB in previous studies on other cancer types. Finally, we concluded that ALDOB may have potential reference value for immunotherapy and can also be used as an independent predictor of prognosis in KIRC.

Review of possible mechanisms of radiotherapy resistance in cervical cancer

Radiotherapy is one of the main treatments for cervical cancer. Early cervical cancer is usually considered postoperative radiotherapy alone. Radiotherapy combined with cisplatin is the standard treatment for locally advanced cervical cancer (LACC), but sometimes the disease will relapse within a short time after the end of treatment. Tumor recurrence is usually related to the inherent radiation resistance of the tumor, mainly involving cell proliferation, apoptosis, DNA repair, tumor microenvironment, tumor metabolism, and stem cells. In the past few decades, the mechanism of radiotherapy resistance of cervical cancer has been extensively studied, but due to its complex process, the specific mechanism of radiotherapy resistance of cervical cancer is still not fully understood. In this review, we discuss the current status of radiotherapy resistance in cervical cancer and the possible mechanisms of radiotherapy resistance, and provide favorable therapeutic targets for improving radiotherapy sensitivity. In conclusion, this article describes the importance of understanding the pathway and target of radioresistance for cervical cancer to promote the development of effective radiotherapy sensitizers.

Pan-cancer analysis of aldolase B gene as a novel prognostic biomarker for human cancers

Aldolase B (ALDOB) gene is essential for the process of glycolysis and differentially expressed in cancers. The aims of this study were to explore the potential role of ALDOB in pan-cancer, in order to deepen the research on the pathological mechanism of cancer. Hence, we used several online tools (TIMER2, GEPIA2, UALCAN, cBioPortal, and MXPRESS) and R language to identify the correlation between the ALDOB expression and survival analysis, genetic alteration, DNA methylation, and immune cell infiltration based on The Cancer Genome Atlas project. The results showed that ALDOB was lowly expressed in pan-cancer. Survival analysis revealed that low expression of ALDOB was markedly related with poor clinical prognosis, while the genetic alteration within ALDOB changed along with the difference of overall survival (OS) and disease-free survival (DFS) prognosis in several cancers. A possible relationship between DNA methylation and ALDOB expression for several tumors was found. Besides, ALDOB expression was confirmed to be associated with tumor immune cell infiltration, especially in breast invasive carcinoma (BRCA), esophageal carcinoma (ESCA), and testicular germ cell tumors (TGCT) cases. Further, the enrichment analysis demonstrated that metabolic pathway was closely related to ALDOB expression. Our results provide a comprehensive pan-cancer analysis and suggest ALDOB could act as a promising tumor predictive biomarker for human cancer.

Ligand fishing as a tool to screen natural products with anticancer potential

Cancer is the second leading cause of death in the world and its incidence is expected to increase with the aging of the world's population and globalization of risk factors. Natural products and their derivatives have provided a significant number of approved anticancer drugs and the development of robust and selective screening assays for the identification of lead anticancer natural products are essential in the challenge of developing personalized targeted therapies tailored to the genetic and molecular characteristics of tumors. To this end, a ligand fishing assay is a remarkable tool to rapidly and rigorously screen complex matrices, such as plant extracts, for the isolation and identification of specific ligands that bind to relevant pharmacological targets. In this paper, we review the application of ligand fishing with cancer-related targets to screen natural product extracts for the isolation and identification of selective ligands. We provide critical analysis of the system configurations, targets, and key phytochemical classes related to the field of anticancer research. Based on the data collected, ligand fishing emerges as a robust and powerful screening system for the rapid discovery of new anticancer drugs from natural resources. It is currently an underexplored strategy according to its considerable potential.

A novel metabolism-related prognostic gene development and validation in gastric cancer

BACKGROUND

The importance of metabolism-related alterations in the development of gastric cancer (GC) is increasingly recognized. The present study aimed to identify metabolism-related genes to facilitate prognosis of GC patients.

METHODS

Gene expression datasets and clinical information of GC patients were downloaded from TCGA and GEO databases. We scored the enrichment of human metabolism-related pathways (n = 86) in GC samples by GSV, constructed prognostic risk models using LASSO algorithm and multivariate Cox regression analysis, combined with clinical information to construct a nomogram, and finally cis score algorithm to analyze the abundance of immune-related cells in different subtypes. We used Weka software to screen for prognosis-related marker genes and finally validated the expression of the selected genes in clinical cancer patient tissues.

RESULTS

We identified that two GC metabolism-related signatures were strongly associated with OS and the levels of immune cell infiltration. Moreover, a survival prediction model for GC was established based on six GC metabolism-related genes. Time-dependent ROC analysis showed good stability of the risk prediction scoring model. The model was successfully validated in an independent ACRG cohort, and the expression trends of key genes were also verified in the GC tissues of patients. DLX1, LTBP2, FGFR1 and MMP2 were highly expressed in the cluster with poorer prognosis while SLC13A2 and SLCO1B3 were highly expressed in the cluster with better prognosis.

CONCLUSIONS

We identified a risk predictive score model based on six metabolism-related genes related to survival, which may serve as prognostic indicators and potential therapeutic targets for GC.

Identification of Differentially Expressed Genes Related to the Lipid Metabolism of Esophageal Squamous Cell Carcinoma by Integrated Bioinformatics Analysis

Purpose: In recent years, lipid metabolism has been reprogrammed to meet the energy and substrate needs of tumorigenesis and development and is a potential new target for cancer treatment. However, the regulatory mechanism of lipid metabolism in esophageal squamous cell carcinoma is not well understood. Methods: We first downloaded the esophageal squamous cell carcinoma (ESCC) gene dataset in the GEO and TCGA databases and analyzed the central differentially expressed genes (DEGs) of ESCC through bioinformatics. Afterwards, the GSEA method was used to analyze the lipid metabolism-related pathway of the central gene in the pathological process of ESCC, and it was determined that the central gene OIP5 was significantly related to the fatty acid metabolism pathway. Our heatmap also revealed that the enrichment of the ACSL family in ESCC tissues was more pronounced than in normal tissues. We hypothesized that OIP5 can regulate the fatty acid metabolism process in ESCC cells and affect the tumorigenic ability of ESCC. Further statistical analysis and experiment were conducted to determine the lipid metabolism-related gene, OIP5′s, expression pattern and clinical significance in ESCC, analyze the effect of OIP5 expression on fatty acid metabolism-related enzymes in ESCC, revealing the specific mechanism of OIP5 that promotes ESCC development. Conclusions: Our study established a correlation between OIP5 expression and clinicopathological factors (tumor size, T stage, N stage, and clinical grade) in esophageal squamous cell carcinoma (p < 0.05). We have also experimentally demonstrated that OIP5 regulates ESCC fatty acid metabolism by influencing the expression of the key enzyme ACSL1 in lipid metabolism.

IMP4 Silencing Inhibits the Malignancy of Lung Adenocarcinoma via ERK Pathway

Our study aimed to elucidate the function of IMP U3 small nucleolar ribonucleoprotein 4 (IMP4) in lung adenocarcinoma (LUAD) and its potential molecular mechanisms. Cell counting kit-8, 5-ethynyl-20-deoxyuridine, flow cytometry, wound healing, and transwell assays were performed to examine the biological behaviour of LUAD cells. mRNA and protein expression levels were determined using quantitative real-time PCR, Western blotting, and immunohistochemistry. In addition, a mouse tumour xenograft model was used to evaluate the role of IMP4 in tumour progression. Furthermore, glycolysis-related indicators were measured. The levels of IMP4 were up-regulated in both human LUAD tissues and cells. IMP4 silencing significantly suppressed proliferation, migration, invasion, and glycolysis; promoted apoptosis; and induced cell cycle arrest in LUAD cells. IMP4 silencing also inactivated the extracellular signal-regulated kinase (ERK) pathway. Moreover, rescue experiments demonstrated that the function of LUAD cells induced by IMP4 overexpression could be reversed by treatment with an ERK pathway inhibitor (SCH772984). In vivo experiments further verified that IMP4 silencing repressed the growth of subcutaneous tumours and glycolysis. IMP4 silencing suppressed the malignancy of LUAD by inactivating ERK signalling.

Targeting Strategies for Aberrant Lipid Metabolism Reprogramming and the Immune Microenvironment in Esophageal Cancer: A Review

Esophageal cancer is of high importance to occurrence, development, and treatment resistance. As evidenced by recent studies, pathways (e.g., Wnt/β-catenin, AMPK, and Hippo) are critical to the proliferation, differentiation, and self-renewal of esophageal cancer. In addition, the above pathways play a certain role in regulating esophageal cancer and act as potential therapeutic targets. Over the past few years, the function of lipid metabolism in controlling tumor cells and immune cells has aroused extensive attention. It has been reported that there are intricate interactions between lipid metabolism reprogramming between immune and esophageal cancer cells, whereas molecular mechanisms should be studied in depth. Immune cells have been commonly recognized as a vital player in the esophageal cancer microenvironment, having complex crosstalk with cancer cells. It is increasingly evidenced that the function of immune cells in the tumor microenvironment (TME) is significantly correlated with abnormal lipid metabolism. In this review, the latest findings in lipid metabolism reprogramming in TME are summarized, and the above findings are linked to esophageal cancer progression. Aberrant lipid metabolism and associated signaling pathways are likely to serve as a novel strategy to treat esophageal cancer through lipid metabolism reprogramming.

Interplay Between m6A RNA Methylation and Regulation of Metabolism in Cancer

Methylation of adenosine in RNA to N6-methyladenosine (m⁶A) is widespread in eukaryotic cells with his integral RNA regulation. This dynamic process is regulated by methylases (editors/writers), demethylases (remover/erasers), and proteins that recognize methylation (effectors/readers). It is now evident that m⁶A is involved in the proliferation and metastasis of cancer cells, for instance, altering cancer cell metabolism. Thus, determining how m⁶A dysregulates metabolic pathways could provide potential targets for cancer therapy or early diagnosis. This review focuses on the link between the m⁶A modification and the reprogramming of metabolism in cancer. We hypothesize that m⁶A modification could dysregulate the expression of glucose, lipid, amino acid metabolism, and other metabolites or building blocks of cells by adaptation to the hypoxic tumor microenvironment, an increase in glycolysis, mitochondrial dysfunction, and abnormal expression of metabolic enzymes, metabolic receptors, transcription factors as well as oncogenic signaling pathways in both hematological malignancies and solid tumors. These metabolism abnormalities caused by m⁶A’s modification may affect the metabolic reprogramming of cancer cells and then increase cell proliferation, tumor initiation, and metastasis. We conclude that focusing on m⁶A could provide new directions in searching for novel therapeutic and diagnostic targets for the early detection and treatment of many cancers.

Metabolic targeting of cancer by a ubiquinone uncompetitive inhibitor of mitochondrial complex I

SMIP004-7 is a small molecule inhibitor of mitochondrial respiration with selective in vivo anti-cancer activity through an as-yet unknown molecular target. We demonstrate here that SMIP004-7 targets drug-resistant cancer cells with stem-like features by inhibiting mitochondrial respiration complex I (NADH:ubiquinone oxidoreductase, complex I [CI]). Instead of affecting the quinone-binding site targeted by most CI inhibitors, SMIP004-7 and its cytochrome P450-dependent activated metabolite(s) have an uncompetitive mechanism of inhibition involving a distinct N-terminal region of catalytic subunit NDUFS2 that leads to rapid disassembly of CI. SMIP004-7 and an improved chemical analog selectively engage NDUFS2 in vivo to inhibit the growth of triple-negative breast cancer transplants, a response mediated at least in part by boosting CD4⁺ and CD8⁺ T cell-mediated immune surveillance. Thus, SMIP004-7 defines an emerging class of ubiquinone uncompetitive CI inhibitors for cell autonomous and microenvironmental metabolic targeting of mitochondrial respiration in cancer.

Recent Strategies to Develop Innovative Photosensitizers for Enhanced Photodynamic Therapy

This review presents a robust strategy to design photosensitizers (PSs) for various species. Photodynamic therapy (PDT) is a photochemical-based treatment approach that involves the use of light combined with a light-activated chemical, referred to as a PS. Attractively, PDT is one of the alternatives to conventional cancer treatment due to its noninvasive nature, high cure rates, and low side effects. PSs play an important factor in photoinduced reactive oxygen species (ROS) generation. Although the concept of photosensitizer-based photodynamic therapy has been widely adopted for clinical trials and bioimaging, until now, to our surprise, there has been no relevant review article on rational designs of organic PSs for PDT. Furthermore, most of published review articles in PDT focused on nanomaterials and nanotechnology based on traditional PSs. Therefore, this review aimed at reporting recent strategies to develop innovative organic photosensitizers for enhanced photodynamic therapy, with each example described in detail instead of providing only a general overview, as is typically done in previous reviews of PDT, to provide intuitive, vivid, and specific insights to the readers.

Expression of fatty acid-binding protein-4 in gastrointestinal stromal tumors and its significance for prognosis

Background

Fatty acid‐binding proteins (FABPs) have been found to be involved in tumorigenesis and development. However, the role of FABP4, a member of the FABPs, in GISTs (Gastrointestinal stromal tumors) remains unclear. This study aimed to investigate the expression of FABP4 and its prognostic value in GISTs.

Methods

FABP4 expression in 125 patients with GISTs was evaluated by immunohistochemical analysis of tissue microarrays. The relationship between FABP4 expression and clinicopathological features and prognosis of GISTs was analyzed.

Results

Multiple logistic regression analysis showed that expression of FABP4 correlated with tumor size and mitotic index. Furthermore, FABP4 level, tumor size, mitotic index, and high AFIP‐Miettinen risk were independent prognostic factors in GISTs. The Kaplan‐Meier survival curve showed that the 5‐year survival rate of patients with high‐FABP4 expression GISTs was lower.

Conclusions

These results suggested that high‐FABP4 expression might be a marker of malignant phenotype of GISTs and poor prognosis.

Tumor Hypoxia Drives Genomic Instability

Cancer is a leading cause of death worldwide. As a common characteristic of cancer, hypoxia is associated with poor prognosis due to enhanced tumor malignancy and therapeutic resistance. The enhanced tumor aggressiveness stems at least partially from hypoxia-induced genomic instability. Therefore, a clear understanding of how tumor hypoxia induces genomic instability is crucial for the improvement of cancer therapeutics. This review summarizes recent developments highlighting the association of tumor hypoxia with genomic instability and the mechanisms by which tumor hypoxia drives genomic instability, followed by how hypoxic tumors can be specifically targeted to maximize efficacy.

A Multi-Omics Study Revealing the Metabolic Effects of Estrogen in Liver Cancer Cells HepG2

Hepatocellular carcinoma (HCC) that is triggered by metabolic defects is one of the most malignant liver cancers. A much higher incidence of HCC among men than women suggests the protective roles of estrogen in HCC development and progression. To begin to understand the mechanisms involving estrogenic metabolic effects, we compared cell number, viability, cytotoxicity, and apoptosis among HCC-derived HepG2 cells that were treated with different concentrations of 2-deoxy-d-glucose (2-DG) that blocks glucose metabolism, oxamate that inhibits lactate dehydrogenase and glycolysis, or oligomycin that blocks ATP synthesis and mitochondrial oxidative phosphorylation. We confirmed that HepG2 cells primarily utilized glycolysis followed by lactate fermentation, instead of mitochondrial oxidative phosphorylation, for cell growth. We hypothesized that estrogen altered energy metabolism via its receptors to carry out its anticancer effects in HepG2 cells. We treated cells with 17β-estradiol (E2), 1,3,5-tris(4-hydroxyphenyl)-4-propyl-1H-pyrazole (PPT) an estrogen receptor (ER) α (ERα) agonist, or 2,3-bis(4-hydroxyphenyl)-propionitrile (DPN), an ERβ agonist. We then used transcriptomic and metabolomic analyses and identified differentially expressed genes and unique metabolite fingerprints that are produced by each treatment. We further performed integrated multi-omics analysis, and identified key genes and metabolites in the gene–metabolite interaction contributed by E2 and ER agonists. This integrated transcriptomic and metabolomic study suggested that estrogen acts on estrogen receptors to suppress liver cancer cell growth via altering metabolism. This is the first exploratory study that comprehensively investigated estrogen and its receptors, and their roles in regulating gene expression, metabolites, metabolic pathways, and gene–metabolite interaction in HCC cells using bioinformatic tools. Overall, this study provides potential therapeutic targets for future HCC treatment.

Integrated Analysis of Expression and Prognostic Values of Acyl-CoA Dehydrogenase short-chain in Colorectal Cancer

Background: Acyl-CoA dehydrogenase short-chain (ACADS) is a crucial enzyme in the fatty acid metabolism pathway located in mitochondria. However, the expression level and prognostic value of ACADS in colorectal cancer (CRC) remain unclear. Methods: The mRNA and protein expression data of ACADS was obtained from The Cancer Genome Atlas (TCGA), Clinical Proteomic Tumor Analysis Consortium (CPTAC), and Oncomine. Prognostic values of ACADS were calculated using Kaplan-Meier survival analysis. Correlations between ACADS and immune infiltration were estimated using TIMER, CIBERSORT, EPIC, quanTIseq, and xCell. The UALCAN and MEXPRESS databases were utilized for Methylation analysis. The co-expression analysis based on mRNA expression and interaction network of ACADS were performed via several online tools. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis on ACADS co-expressed genes were performed using the Metascape. Results: The expression analysis demonstrated that ACADS was down-regulated in CRC tissues compared with paired normal tissue. Expression of ACADS was found to be significantly associated with clinical cancer stages and the consensus molecular subgroups (CMS) constituent ratio in CRC patients. Besides, lower ACADS expression was found to predict poor prognosis and be significantly associated with common immune checkpoint genes and MMR genes in CRC. ACADS expression levels were positively related to B cells, CD4⁺ T cells, CD8⁺ T cells, M1 macrophages, neutrophils, and Tregs, while negatively correlated with M0 macrophages, M2 macrophages. The methylation level of ACADS in normal tissues was significantly higher than that in tumor tissues, and several methylation sites were identified. The enrichment analysis suggested the co-expressed genes mainly enriched in cell mitochondrial metabolism. Conclusions: The present study provided multilevel evidences for expression of ACADS in CRC and the function of ACADS in prognostic prediction, immune infiltration, and methylation. ACADS might have the potential as the novel biomarker and therapeutic target in CRC patients.

Biological Evaluation of Oxindole Derivative as a Novel Anticancer Agent against Human Kidney Carcinoma Cells

Renal cell carcinoma has emerged as one of the leading causes of cancer-related deaths in the USA. Here, we examined the anticancer profile of oxindole derivatives (SH-859) in human renal cancer cells. Targeting 786-O cells by SH-859 inhibited cell growth and affected the protein kinase B/mechanistic target of rapamycin 1 pathway, which in turn downregulated the expression of glycolytic enzymes, including lactate dehydrogenase A and glucose transporter-1, as well as other signaling proteins. Treatment with SH-859 altered glycolysis, mitochondrial function, and levels of adenosine triphosphate and cellular metabolites. Flow cytometry revealed the induction of apoptosis and G0/G1 cell cycle arrest in renal cancer cells following SH-859 treatment. Induction of autophagy was also confirmed after SH-859 treatment by acridine orange and monodansylcadaverine staining, immunocytochemistry, and Western blot analyses. Finally, SH-859 also inhibited the tumor development in a xenograft model. Thus, SH-859 can serve as a potential molecule for the treatment of human renal carcinoma.

E3 ligase ZFP91 inhibits Hepatocellular Carcinoma Metabolism Reprogramming by regulating PKM splicing

Rationale: Hepatocellular carcinoma (HCC) is one of the most lethal cancers, and few molecularly targeted anticancer therapies have been developed to treat it. Thus, the identification of new therapeutic targets is urgent. Metabolic reprogramming is an important hallmark of cancer. However, how ubiquitin ligases are involved in the regulation of cancer metabolism remains poorly understood. Methods: RT-PCR, western blot and IHC were used to determine ZFP91 expression. RNAi, cell proliferation, colony formation and transwell assays were used to determine the in vitro functions of ZFP91. Mouse xenograft models were used to study the in vivo effects of ZFP91. Co-IP together with mass spectrometry or western blot was utilized to investigate protein-protein interaction. Ubiquitination was analyzed using IP together with western blot. RNA splicing was assessed by using RT-PCR followed by restriction digestion. Lactate production and glucose uptake assays were used to analyze cancer metabolism. Results: We identified that an E3 ligase zinc finger protein 91 (ZFP91) suppressed HCC metabolic reprogramming, cell proliferation and metastasis in vitro and in vivo. Mechanistically, ZFP91 promoted the Lys48-linked ubiquitination of the oncoprotein hnRNP A1 at lysine 8 and proteasomal degradation, thereby inhibiting hnRNP A1-dependent PKM splicing, subsequently resulting in higher PKM1 isoform formation and lower PKM2 isoform formation and suppressing HCC glucose metabolism reprogramming, cell proliferation and metastasis. Moreover, HCC patients with lower levels of ZFP91 have poorer prognoses, and ZFP91 is an independent prognostic factor for patients with HCC. Conclusions: Our study identifies ZFP91 as a tumor suppressor of hepatocarcinogenesis and HCC metabolism reprogramming and proposes it as a novel prognostic biomarker and therapeutic target of HCC.

Energy metabolism in cancer stem cells

Normal cells mainly rely on oxidative phosphorylation as an effective energy source in the presence of oxygen. In contrast, most cancer cells use less efficient glycolysis to produce ATP and essential biomolecules. Cancer cells gain the characteristics of metabolic adaptation by reprogramming their metabolic mechanisms to meet the needs of rapid tumor growth. A subset of cancer cells with stem characteristics and the ability to regenerate exist throughout the tumor and are therefore called cancer stem cells (CSCs). New evidence indicates that CSCs have different metabolic phenotypes compared with differentiated cancer cells. CSCs can dynamically transform their metabolic state to favor glycolysis or oxidative metabolism. The mechanism of the metabolic plasticity of CSCs has not been fully elucidated, and existing evidence indicates that the metabolic phenotype of cancer cells is closely related to the tumor microenvironment. Targeting CSC metabolism may provide new and effective methods for the treatment of tumors. In this review, we summarize the metabolic characteristics of cancer cells and CSCs and the mechanisms of the metabolic interplay between the tumor microenvironment and CSCs, and discuss the clinical implications of targeting CSC metabolism.

Regulators of glucose uptake in thyroid cancer cell lines

Abstract

Thyroid cancer is the most common sort of endocrine-related cancer with more prevalent in women and elderly individuals which has quickly widespread expansion in worldwide over the recent decades. Common features of malignant thyroid cells are to have accelerated metabolism and increased glucose uptake to optimize their energy supply which provides a fundamental advantage for growth. In tumor cells the retaining of required energy charge for cell survival is imperative, indeed glucose transporters are enable of promoting of this task. According to this relation it has been reported the upregulation of glucose transporters in various types of cancers. Human studies indicated that poor survival can be occurred following the high levels of GLUT1 expression in tumors. GLUT-1 and GLUT3 are the glucose transporters which seems to be mainly engaged with the oncogenesis of thyroid cancer and their expression in malignant tissues is much more than in the normal one. They are promising targets for the advancement of anticancer strategies. The lack of oncosuppressors have dominant effect on the membrane expression of GLUT1 and glucose uptake. Overexpression of hypoxia inducible factors have been additionally connected with distant metastasis in thyroid cancers which mediates transcriptional regulation of glycolytic genes including GLUT1 and GLUT3. Though the physiological role of the thyroid gland is well illustrated, but the metabolic regulations in thyroid cancer remain evasive. In this study we discuss proliferation pathways of the key regulators and signaling molecules such as PI3K-Akt, HIF-1, MicroRNA, PTEN, AMPK, BRAF, c-Myc, TSH, Iodide and p53 which includes in the regulation of GLUTs in thyroid cancer cells. Incidence of deregulations in cellular energetics and metabolism are the most serious signs of cancers. In conclusion, understanding the mechanisms of glucose transportation in normal and pathologic thyroid tissues is critically important and could provide significant insights in science of diagnosis and treatment of thyroid disease.

PHTF2 regulates lipids metabolism in gastric cancer

Identification of hub genes and key pathways of gastric cancer was recognized to be essential to elucidate the tumorigenesis of GC. This study was aimed to identify the differentially expressed genes (DEGs) in GC via bioinformatics methods and their related pathways involved in the pathological process of GC. Gene expression profile datasets acquired by microarray chips or RNA-seq were downloaded from GEO dataset and TCGA, and 298 differentially expressed genes was identified. The Gene Ontology (GO) and Kyoto Gene and Genomic Encyclopedia (KEGG) pathways of DEGs were then analyzed by the DAVID database to elucidate the potential molecular functions of DEGs. The protein-protein interaction (PPI) network of DEGs was further analyzed with the STRING database and PHTF2 was identified as a hub gene in the PPI network. Subsequently, PHTF2 was found to be highly expressed in different subtypes of gastric cancer tissues obtained from TCGA database or clinical patients, resulting with a poor prognosis. By GSEA, PHTF2 was found to significantly enrich the fatty acid metabolism pathway in gastric cancer. Moreover, PHTF2-regulated lipids metabolism significantly affected the tumorigenesis of GC cells. In summary, this work identified a new mechanism by which PHTF2 precipitated in the pathological process of GC by regulating cellular lipid metabolism.

Multifaceted Aspects of Metabolic Plasticity in Human Cholangiocarcinoma: An Overview of Current Perspectives

Cholangiocarcinoma (CCA) is a deadly tumor without an effective therapy. Unique metabolic and bioenergetics features are important hallmarks of tumor cells. Metabolic plasticity allows cancer cells to survive in poor nutrient environments and maximize cell growth by sustaining survival, proliferation, and metastasis. In recent years, an increasing number of studies have shown that specific signaling networks contribute to malignant tumor onset by reprogramming metabolic traits. Several evidences demonstrate that numerous metabolic mediators represent key-players of CCA progression by regulating many signaling pathways. Besides the well-known Warburg effect, several other different pathways involving carbohydrates, proteins, lipids, and nucleic acids metabolism are altered in CCA. The goal of this review is to highlight the main metabolic processes involved in the cholangio-carcinogeneis that might be considered as potential novel druggable candidates for this disease.

CCAT2 contributes to hepatocellular carcinoma progression via inhibiting miR-145 maturation to induce MDM2 expression

Long noncoding RNA colon cancer-associated transcript 2 (CCAT2) has been recently found to function as an oncogene in hepatocellular carcinoma (HCC). However, the mechanisms of CCAT2 in HCC development remain to be further explored. In the present study, we found that CCAT2 was abnormally upregulated in HCC cells and tissue specimens, exhibiting an inverse correlation with microRNA (miR)-145 expression. Mechanistic investigation showed that CCAT2 selectively blocked miR-145 processing, leading to decreased mature miR-145 presence. Both the in vitro and in vivo effects of CCAT2 knockdown on the proliferation and metastasis of HCC cells were reversed by miR-145 inhibitor, indicating that miR-145 modulation accounts for CCAT2-meditated HCC progression. Furthermore, miR-145 mimic dramatically suppressed HCC cells' proliferation and metastasis, revealing a tumor suppressor role of miR-145 in HCC. Mechanistically, MDM2 was predicted to be a potential target of miR-145. The luciferase and western blot assay demonstrated that miR-145 mimic largely inhibited MDM2 3'-untranslated region luciferase activity and MDM2 expression, followed by the upregulation of p53/p21 expression. Finally, the coexpression of MDM2 in miR-145 mimic-transfected HCC cells was able to largely compromise the inhibitory effects of miR-145 mimic on HCC cells' proliferation and metastasis in vitro and tumor formation in a xenograft model, confirming MDM2 is the critical mediator of miR-145 in HCC. In summary, our findings indicated that CCAT2 selectively blocks the miR-145 maturation process and plays an oncogene in HCC. Furthermore, a novel CCAT2/miR-145/MDM2 axis was revealed in HCC development and might provide a new target in the molecular treatment of HCC.

Glucose-Dependent FOXM1 Promotes Epithelial-to-Mesenchymal Transition Via Cellular Metabolism and Targeting Snail in Human Pancreatic Cancer

OBJECTIVES

Transcription factor Forkhead box protein M1 (FOXM1) plays critical roles in the progression of cancer including epithelial-to-mesenchymal transition (EMT). The aim of this study is to characterize the regulatory mechanisms of FOXM1 in EMT via pancreatic cancer metabolism.

METHODS

We investigated the regulation of EMT via mitochondrial respiration by FOXM1 using pancreatic cancer cell lines HPAC and PANC-1 and normal human pancreatic duct epithelial cells.

RESULTS

Forkhead box protein M1 and Snail were strongly expressed in HPAC and PANC-1. Epithelial-to-mesenchymal transition-modulated claudin-1 level was lower in PANC-1 than in HPAC. In both cell lines in low-glucose medium, FOXM1 and Snail were decreased and claudin-1 was increased. Knockdown of FOXM1 increased claudin-1 and decreased Snail in both cell lines. Low-glucose medium and downregulation of FOXM1 inhibited the cell migration in both cell lines. In both cell lines, mitochondrial respiration was at higher levels in low-glucose medium than in high-glucose medium. Downregulation of FOXM1 induced mitochondrial respiration in high-glucose medium. In normal human pancreatic duct epithelial cells, FOXM1 and Snail were low and claudin-1 was highly expressed, whereas overexpression of FOXM1 decreased claudin-1.

CONCLUSIONS

Glucose-dependent FOXM1 promoted EMT via Snail and pancreatic cancer metabolism.

Inhibition of fatty acid catabolism augments the efficacy of oxaliplatin-based chemotherapy in gastrointestinal cancers

Gastrointestinal cancer causes countless deaths every year due to therapeutic resistance. However, whether metabolic alterations contribute to chemoresistance is not well understood. In this study, we report that fatty acid (FA) catabolism was activated in gastrointestinal cancer cells treated with oxaliplatin, which exhibited higher expression of the rate-limiting enzymes carnitine palmitoyltransferase 1B (CPT1B) and CPT2. The clinical analysis also showed that high expression of these enzymes was associated with poor oxaliplatin-based chemotherapy outcomes in patients. Furthermore, genetic or pharmacological inhibition of CPT2 with perhexiline disturbed NADPH and redox homeostasis and increased reactive oxygen species (ROS) generation and cell apoptosis in gastrointestinal cancer cells following oxaliplatin treatment. Specifically, the combination of oxaliplatin and perhexiline significantly suppressed the progression of gastrointestinal cancer in cell-based xenograft and patient-derived xenograft (PDX) models. Mechanistically, CPT2 was transcriptionally upregulated by nuclear factor of activated T cells 3 (NFATc3), which translocated to the nucleus in response to oxaliplatin treatment. In summary, our study suggests that the inhibition of CPT-mediated FA catabolism combined with conventional chemotherapy is a promising therapeutic strategy for patients with gastrointestinal cancers.

Knockdown of Pyruvate Kinase M2 Inhibits Cell Proliferation, Metabolism, and Migration in Renal Cell Carcinoma

Emerging evidence indicates that the activity of pyruvate kinase M2 (PKM2) isoform is crucial for the survival of tumor cells. However, the molecular mechanism underlying the function of PKM2 in renal cancer is undetermined. Here, we reveal the overexpression of PKM2 in the proximal tubule of renal tumor tissues from 70 cases of patients with renal carcinoma. The functional role of PKM2 in human renal cancer cells following small-interfering RNA-mediated PKM2 knockdown, which retarded 786-O cell growth was examined. Targeting PKM2 affected the protein kinase B (AKT)/mechanistic target of the rapamycin 1 (mTOR) pathway, and downregulated the expression of glycolytic enzymes, including lactate dehydrogenase A and glucose transporter-1, and other downstream signaling key proteins. PKM2 knockdown changed glycolytic metabolism, mitochondrial function, adenosine triphosphate (ATP) level, and intracellular metabolite formation and significantly reduced 786-O cell migration and invasion. Acridine orange and monodansylcadaverine staining, immunocytochemistry, and immunoblotting analyses revealed the induction of autophagy in renal cancer cells following PKM2 knockdown. This is the first study to indicate PKM2/AKT/mTOR as an important regulatory axis mediating the changes in the metabolism of renal cancer cells.

Integrative proteomic and phosphoproteomic profiling of prostate cell lines

Background

Prostate cancer is a major public health issue, mainly because patients relapse after androgen deprivation therapy. Proteomic strategies, aiming to reflect the functional activity of cells, are nowadays among the leading approaches to tackle the challenges not only of better diagnosis, but also of unraveling mechanistic details related to disease etiology and progression.

Methods

We conducted here a large SILAC-based Mass Spectrometry experiment to map the proteomes and phosphoproteomes of four widely used prostate cell lines, namely PNT1A, LNCaP, DU145 and PC3, representative of different cancerous and hormonal status.

Results

We identified more than 3000 proteins and phosphosites, from which we quantified more than 1000 proteins and 500 phosphosites after stringent filtering. Extensive exploration of this proteomics and phosphoproteomics dataset allowed characterizing housekeeping as well as cell-line specific proteins, phosphosites and functional features of each cell line. In addition, by comparing the sensitive and resistant cell lines, we identified protein and phosphosites differentially expressed in the resistance context. Further data integration in a molecular network highlighted the differentially expressed pathways, in particular migration and invasion, RNA splicing, DNA damage repair response and transcription regulation.

Conclusions

Overall, this study proposes a valuable resource toward the characterization of proteome and phosphoproteome of four widely used prostate cell lines and reveals candidates to be involved in prostate cancer progression for further experimental validation.

Emerging roles of aerobic glycolysis in breast cancer

Altered aerobic glycolysis is a well-recognized characteristic of cancer cell energy metabolism, known as the Warburg effect. Even in the presence of abundant oxygen, a majority of tumor cells produce substantial amounts of energy through a high glycolytic metabolism, and breast cancer (BC) is no exception. Breast cancer continues to be the second leading cause of cancer-associated mortality in women worldwide. However, the precise role of aerobic glycolysis in the development of BC remains elusive. Therefore, the present review attempts to address the implication of key enzymes of the aerobic glycolytic pathway including hexokinase (HK), phosphofructokinase (PFK) and pyruvate kinase (PK), glucose transporters (GLUTs), together with related signaling pathways including protein kinase B(PI3K/AKT), mammalian target of rapamycin (mTOR) and adenosine monophosphate-activated protein kinase (AMPK) and transcription factors (c-myc, p53 and HIF-1) in the research of BC. Thus, the review of aerobic glycolysis in BC may evoke novel ideas for the BC treatment.

Toll-like receptor 2 regulates metabolic reprogramming in gastric cancer via superoxide dismutase 2

Toll-like receptors (TLRs) play critical roles in host defense after recognition of conserved microbial- and host-derived components, and their dysregulation is a common feature of various inflammation-associated cancers, including gastric cancer (GC). Despite the recent recognition that metabolic reprogramming is a hallmark of cancer, the molecular effectors of altered metabolism during tumorigenesis remain unclear. Here, using bioenergetics function assays on human GC cells, we reveal that ligand-induced activation of TLR2, predominantly through TLR1/2 heterodimer, augments both oxidative phosphorylation (OXPHOS) and glycolysis, with a bias toward glycolytic activity. Notably, DNA microarray-based expression profiling of human cancer cells stimulated with TLR2 ligands demonstrated significant enrichment of gene-sets for oncogenic pathways previously implicated in metabolic regulation, including reactive oxygen species (ROS), p53 and Myc. Moreover, the redox gene encoding the manganese-dependent mitochondrial enzyme, superoxide dismutase (SOD)2, was strongly induced at the mRNA and protein levels by multiple signaling pathways downstream of TLR2, namely JAK-STAT3, JNK MAPK and NF-κB. Furthermore, siRNA-mediated suppression of SOD2 ameliorated the TLR2-induced metabolic shift in human GC cancer cells. Importantly, patient-derived tissue microarrays and bioinformatics interrogation of clinical datasets indicated that upregulated expression of TLR2 and SOD2 were significantly correlated in human GC, and the TLR2-SOD2 axis was associated with multiple clinical parameters of advanced stage disease, including distant metastasis, microvascular invasion and stage, as well as poor survival. Collectively, our findings reveal a novel TLR2-SOD2 axis as a potential biomarker for therapy and prognosis in cancer.

KLF8 is associated with poor prognosis and regulates glycolysis by targeting GLUT4 in gastric cancer

Krüppel‐like transcription factor (KLF) family is involved in tumorigenesis in different types of cancer. However, the importance of KLF family in gastric cancer is unclear. Here, we examined KLF gene expression in five paired liver metastases and primary gastric cancer tissues by RT‐PCR, and immunohistochemistry was used to study KLF8 expression in 206 gastric cancer samples. The impact of KLF8 expression on glycolysis, an altered energy metabolism that characterizes cancer cells, was evaluated. KLF8 showed the highest up‐regulation in liver metastases compared with primary tumours among all KLF members. Higher KLF8 expression associated with larger tumour size (P < 0.001), advanced T stage (P = 0.003) and N stage (P < 0.001). High KLF8 expression implied shorter survival outcome in both TCGA and validation cohort (P < 0.05). Silencing KLF8 expression impaired the glycolysis rate of gastric cancer cells in vitro. Moreover, high KLF8 expression positively associated with SUVmax in patient samples. KLF8 activated the GLUT4 promoter activity in a dose‐dependent manner (P < 0.05). Importantly, KLF8 and GLUT4 showed consistent expression patterns in gastric cancer tissues. These findings suggest that KLF8 modulates glycolysis by targeting GLUT4 and could serve as a novel biomarker for survival and potential therapeutic target in gastric cancer.

Metabolomics Analysis in Serum from Patients with Colorectal Polyp and Colorectal Cancer by 1H-NMR Spectrometry

Colorectal cancer (CRC) is one of the leading causes of cancer-related death worldwide. Colorectal adenomatous polyps are at high risk for the development of CRC. In this report, we described the metabolic changes in the sera from patients with colorectal polyps and CRC by using the NMR-based metabolomics. 110 serum samples were collected from patients and healthy controls, including 40 CRC patients, 32 colorectal polyp patients, and 38 healthy controls. The metabolic profiles and differential metabolites of sera were analyzed by multivariate statistical analysis (MSA), including principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), and orthogonal partial least squares discriminant analysis (OPLS-DA) methods. A total of 23 differential metabolites were identified from MSA. According to the pathway analysis and multivariate ROC curve-based exploratory analysis by using the relative concentrations of differential metabolites, we found abnormal metabolic pathways and potential biomarkers involved with the colorectal polyp and CRC. The results showed that the pyruvate metabolism and glycerolipid metabolism were activated in colorectal polyps. And the glycolysis and glycine, serine, and threonine metabolism were activated in CRC. The changed metabolism may promote cellular proliferation. In addition, we found that the rates of acetate/glycerol and lactate/citrate could be the potential biomarkers in colorectal polyp and CRC, respectively. The application of ¹H-NMR metabolomics analysis in serum has interesting potential as a new detection and diagnostic tool for early diagnosis of CRC.

The KLF14 Transcription Factor Regulates Glycolysis by Downregulating LDHB in Colorectal Cancer

The Krüppel-like transcription factor 14 (KLF14) is a critical regulator of a wide array of biological processes. However, the role of KLF14 in colorectal cancer (CRC) isn't fully investigated. This study aimed to explore the clinicopathological significance and potential role of KLF14 in the carcinogenesis and progression of CRC. A tissue microarray consisting of 185 samples from stage I-III CRC patients was adopted to analyze the correlation between KLF14 expression and clinicopathological parameters, as well as overall survival (OS) and disease-free survival (DFS). The underlying mechanisms of altered KLF14 expression on glycolysis were studied using in vitro and patients' samples. The results showed that KLF14 expression was downregulated in CRC than their normal controls. Low KLF14 expression correlated with advanced T stage (P< 0.001) and N stage (P= 0.040), and larger tumor size (P= 0.008). Lost KLF14 expression implied shorter OS and DFS after colectomy in both univariate and multivariate survival analysis (P<0.05). Experimentally, restore KLF14 expression significantly decreased the rate of glycolysis both in vitro and in patients' sample. Mechanically, KLF14 regulated glycolysis by downregulating glycolytic enzyme LDHB. Collectively, KLF14 is a novel prognostic biomarker for survival in CRC, and downregulation of KLF14 in CRC prompts glycolysis by target LDHB. Hence, KLF14 could constitute potential prognostic predictors and therapeutic targets for CRC.

Tumor Starvation Induced Spatiotemporal Control over Chemotherapy for Synergistic Therapy

By integrating the characteristics of each therapy modality and material chemistry, a multitherapy modality is put forward: tumor starvation triggered synergism with sensitized chemotherapy. Following starvation-induced amplification of pathological abnormalities in tumors, chemotherapy is arranged to be locally activated and accurately reinforced to perfect multitherapy synergism from spatial and temporal perspectives. To this end, glucose oxidase (GOD) and a hypoxic prodrug of tirapazamine (TPZ) are loaded in acidity-decomposable calcium carbonate (CaCO₃ ) nanoparticles concurrently tethered by hyaluronic acid. This hybrid nanotherapeutic shows a strong tendency to accumulate in tumors postinjection due to the cooperation between passive and active targeting mechanisms. The GOD-driven oxidation reaction deprives tumors of glucose for starvation therapy and concomitantly induces tumorous abnormality amplifications including elevated acidity and exacerbated hypoxia. Programmatically, the acidity amplification causes CaCO₃ decomposition, offering not only spatial control over the liberation of embedded TPZ just within tumors but also the temporal control over timely chemotherapy initiation to match the occurrence of hypoxia amplification and thus benefiting perfect synergism between starvation therapy and chemotherapy.

Histone deacetylase-1 as a prognostic factor and mediator of gastric cancer progression by enhancing glycolysis

Histone deacetylase 1 (HDAC1) has been shown to be closely associated with tumor development. We investigated its effects on survival and biological behavior in gastric cancer (GC). HDAC1 expression and glycolysis activity were analyzed in a cohort of 252 samples of primary GC tumors and in vitro study. High HDAC1 (HDAC1^High) staining was seen in 60.7% patients with GCs, which was significantly greater than was seen in normal epithelial cells (19.4%; P < .005). HDAC1^High expression was associated with larger tumor size (P = .001), advanced T stage (P = .001), lymph node metastases (N stage; P < .001), and lymphovascular invasion (P = .005). Univariate and multivariate survival analyses showed HDAC1 expression to be an independent prognostic factor for both disease-free survival and overall survival (P < .05). In vitro studies showed a notably decreased glycolysis rate in HDAC1 knockdown cells. In patients' samples, HDAC1^High expression was always accompanied with high Maximal standardized uptake value (SUVmax) value (P < .05). A hypoxia-inducible factor (HIF)-1α response element-luciferase reporter system showed HDAC1 to affect HIF1α activity in a dose-dependent manner. In conclusion, HDAC1 promotes glycolysis in GC and affects HIF-1α activity in tumor progression and metastasis. HDAC1^High expression was also an independent adverse prognostic factor for overall survival and disease-free survival.

Dysregulated cancer cell transdifferentiation into erythrocytes is an additional metabolic stress in hepatocellular carcinoma

A number of human and canine hepatocellular carcinoma tissues showed clear signs of hypoxia indicated by HIF1α-activation and the presence of large clusters of cells resembling erythrocytes at different stages of nuclear elimination without any defined endothelial cell lining or blood vessel walls. Differentiated erythrocytic identity of such cells in hepatocellular carcinoma tissues was apparent from their non-nucleated and evolving basophilic to eosinophilic staining characteristics. In addition to the fully differentiated non-nucleated mesenchymal cell clusters, the onset of erythroblastic transdifferentiation was apparent from the activation of Glycophorin A, a marker of erythrocytic progenitors, in some epithelial cancer cells. Activation of canonical Wnt signalling in such tumours was apparent from the expression of Wnt2 ligand and active β-catenin translocation into the nucleus indicating Wnt signalling to be one of the key signalling pathways participating in such cell transdifferentiation. Sonic hedgehog and bone morphogenetic protein signalling along with Sulf1/Sulf2 activation was also observed in such hepatocellular carcinoma tissue samples. The presence of stem cell markers and the cell signalling pathways associated with erythropoiesis, and the detection of messenger RNAs for both α and β haemoglobins, support the assumption that hepatocellular carcinoma cells have the potential to undergo cell fate change despite this process being dysregulated as indicated by the lack of simultaneous generation of endothelial cell lining. Lack of blood vessel walls or endothelial cell lining around erythrocytic clusters was confirmed by non-detection of multiple blood vessel markers such as vWF, CD146 and smooth muscle α-actin that were clearly apparent in normal and unaffected adjacent regions of hepatocellular carcinoma livers. In addition to the activation of Glycophorin A, transdifferentiation of some hepatocellular carcinoma hepatocytes into other cell fates was further confirmed by the activation of some stem cell markers, for example, NANOG and OCT4 transcription factors, not only by reverse transcription polymerase chain reaction but also by their restricted expression in such cells at protein level.

HMGB2 promotes the malignancy of human gastric cancer and indicates poor survival outcome

HMGB2 is an important protein in carcinogenesis. However, little is known about the specific role of HMGB2 in gastric cancer. In the present study, HMGB2 expression was evaluated in 198 primary gastric cancer tissues and their adjacent nontumor controls. The correlation between HMGB2 expression and clinico-pathological features and survival was assessed. The effect of HMGB2 on cell proliferation, invasion, and glycolysis was examined in vitro. The expression of HMGB2 was significantly increased in human gastric cancer when compared with nontumor tissues (P < .001). High HMGB2 expression correlated with large tumor size (P = .001), advanced T stage (P = .007), and presence of lymph node metastasis (P = .004). Moreover, high HMGB2 expression was validated as an independent prognostic factor in both univariate and multivariate analyses (P < .05). Experimentally, silencing HMGB2 expression by stable transfected shRNA significantly decreased the proliferation, invasion, and glycolysis of gastric cancer cells. In conclusion, HMGB2 is a novel prognostic biomarker for survival in gastric cancer, and knockdown HMGB2 expression in gastric cancer cells attenuated proliferation and invasion, and impaired glycolysis in gastric cancer cells. Hence, HMGB2 may serve as a new biomarker and a potential therapeutic target in gastric cancer.

New strategies for targeting glucose metabolism-mediated acidosis for colorectal cancer therapy

Colorectal cancer (CRC) is a heterogeneous group of diseases that are the result of abnormal glucose metabolism alterations with high lactate production by pyruvate to lactate conversion, which remodels acidosis and offers an evolutional advantage for tumor cells, even enhancing their aggressive phenotype. This review summarizes recent findings that involve multiple genes, molecules, and downstream signaling in the dysregulated glycolytic pathway, which can allow a tumor to initiate acid byproducts and to progress, thereby resulting in acidosis commonly found in the tumor microenvironment of CRC. Moreover, the relationship between CRC cells and the tumor acidic microenvironment, especially for regulating lactate production and lactate dehydrogenase A levels, is also discussed, as well as comprehensively defining different aspects of glycolytic pathways that affect cancer cell proliferation, invasion, and migration. Furthermore, this review concentrates on glucose metabolism-mediated transduction factors in CRC, which include acid-sensing ion channels, triosephosphate isomerase and key glycolysis-related enzymes that regulate glycolytic metabolites, coupled with the effect on tumor cell glycolysis as well as signaling pathways. In conclusion, glucose metabolism mediated by glycolytic pathways that are integral to tumor acidosis in CRC is demonstrated. Therefore, selective metabolic inhibitors or agents against these targets in glucose metabolism through glycolytic pathways may be clinically useful to regulate the tumor's acidic microenvironment for CRC treatment and to identify specific targets that regulate tumor acidosis through a cancer patient-personalized approach. Furthermore, strategies for modifying the metabolic processes that effectively inhibit cancer cell growth and tumor progression and activate potent anticancer effects may provide more effective antitumor prospects for CRC therapy.

Methylation Signature Genes Identification of the Lung Squamous Cell Carcinoma Occurrence and Recognition Research

DNA methylation (DNAm) is one of the most important epigenetic event effecting gene expression, and aberrant DNAm has been implicated in the initiation and progression of human cancers. To identify methylation (ME) signature genes for the pathogenesis of lung squamous cell carcinoma (LUSC), the pattern recognition method was used to analyze the genome-wide gene ME data, which were collected from the LUSC normal and cancer stage I samples in The Cancer Genome Atlas project database. A total of 102 ME signature genes were identified by means of a combination of statistical methods such as correlation, analysis of variance, and Elastic Net. The accuracy and specificity are all above 99%, sensitivity is 100%, and Matthews correlation coefficient is higher than 0.99 through the machine learning method modeling, which are higher than the previous study. The Kyoto Encyclopedia of Genes and Genomes pathway analysis and Gene Ontology enrichment analysis indicated the highly related relationship among these genes. They also indicated the immediate relationship between our signature genes and the occurrence of LUSC, which is very important to the understanding of its mechanism and to the development of new targeted therapy.

Aldolase A as a prognostic factor and mediator of progression via inducing epithelial-mesenchymal transition in gastric cancer

Glycolysis is regarded as the hallmark of cancer development and progression, which involves a multistep enzymatic reaction. This study aimed to explore the clinicopathological significance and potential role of glycolytic enzyme aldolase A (ALDOA) in the carcinogenesis and progression of gastric cancer (GC). ALDOA was screened from three paired liver metastasis tissues and primary GC tissues and further explored with clinical samples and in vitro studies. The ALDOA protein level significantly correlated with a larger tumor diameter (P = .004), advanced T stage (P < .001), N stage (P < .001) and lymphovascular invasion (P = .001). Moreover, the expression of ALDOA was an independent prognostic factor for the 5‐year overall survival and disease‐free survival of patients with GC in both univariate and multivariate survival analyses (P < .05). Silencing the expression of ALDOA in GC cell lines significantly impaired cell growth, proliferation and invasion ability (P < .05). Knockdown of the expression of ALDOA reversed the epithelial–mesenchymal transition process. Mechanically, ALDOA could affect the hypoxia‐inducible factor (HIF)‐1α activity as demonstrated by the HIF‐1α response element–luciferase activity in GC cells. Collectively, this study revealed that ALDOA was a potential biomarker of GC prognosis and was important in the carcinogenesis and progression of human GC.

A dual-function fluorescent probe for monitoring the degrees of hypoxia in living cells via the imaging of nitroreductase and adenosine triphosphate

A new dual-function fluorescent probe is developed for detecting nitroreductase (NTR) and adenosine triphosphate (ATP) with different responses. Imaging application of the probe reveals that intracellular NTR and ATP display an adverse changing trend during a hypoxic process and ATP can serve as a new sign for cell hypoxia.

Triose-phosphate isomerase is a novel target of miR-22 and miR-28, with implications in tumorigenesis

Aerobic glycolysis is the hallmark of many cancer cells that results in a high rate of adenosine triphosphate (ATP) production and, more importantly, biosynthetic intermediates, which are required by the fast-growing tumor cells. The molecular mechanism responsible for the increased glycolytic influx of tumor cells is still not fully understood. In the present study, we have attempted to address the above question by exploring the role of the glycolytic enzyme, triose-phosphate isomerase (TPI), in the cancer cells. The western blot analysis of the 30 human colorectal cancer samples depicted higher post-transcriptional expression of TPI in the tumor tissue relative to the normal tissue. In addition, we identified two novel microRNAs, miR-22 and miR-28, that target the TPI messenger RNA (mRNA) and regulate its expression. miR-22 and the miR-28 showed significant inverse expression status viz-a-viz the expression of the TPI. The specificity of the miR-22/28 regulation of the TPI mRNA was confirmed by various biochemical and mutagenic assays. Moreover, the hypoxia conditions resulted in an increased expression of the TPI protein, with a concomitant decrease in miR-22/28. The physiological significance of the TPI and miR-22/28 interaction for the glycolytic influx was confirmed by the l-lactate production in the HCT-116^+/+ cells. Overall, our data demonstrate the novel microRNA mediated post-transcriptional regulation of the TPI glycolytic enzyme, which may be one of the possible reasons for the increased glycolytic capacity of the tumor cells.

Exploiting ROS and metabolic differences to kill cisplatin resistant lung cancer

Cisplatin resistance remains a major problem in the treatment of lung cancer. We have discovered that cisplatin resistant (CR) lung cancer cells, regardless of the signaling pathway status, share the common parameter which is an increase in reactive oxygen species (ROS) and undergo metabolic reprogramming. CR cells were no longer addicted to the glycolytic pathway, but rather relied on oxidative metabolism. They took up twice as much glutamine and were highly sensitive to glutamine deprivation. Glutamine is hydrolyzed to glutamate for glutathione synthesis, an essential factor to abrogate high ROS via xCT antiporter. Thus, blocking glutamate flux using riluzole (an amyotropic lateral sclerosis approved drug) can selectively kill CR cells in vitro and in vivo. However, we discovered here that glutathione suppression is not the primary pathway in eradicating the CR cells. Riluzole can lead to further decrease in NAD+ (nicotinamide adenine dinucleotide) and lactate dehydrogenase-A (LDHA) expressions which in turn further heightened oxidative stress in CR cells. LDHA knocked-down cells became hypersensitive to riluzole treatments and possessed increased levels of ROS. Addition of NAD+ re-stabilized LDHA and reversed riluzole induced cell death. Thus far, no drugs are available which could overcome cisplatin resistance or kill cisplatin resistant cells. CR cells possess high levels of ROS and undergo metabolic reprogramming. These metabolic adaptations can be exploited and targeted by riluzole. Riluzole may serve as a dual-targeting agent by suppression LDHA and blocking xCT antiporter. Repurposing of riluzole should be considered for future treatment of cisplatin resistant lung cancer patients.

Osteoglycin (OGN) reverses epithelial to mesenchymal transition and invasiveness in colorectal cancer via EGFR/Akt pathway

Background

Many types of cancers are devoid of the small leucine-rich proteoglycans: osteoglycin (OGN), but its role in tumorigenesis is poorly studied especially in colorectal cancers (CRC). Here we aim to evaluate the relationship between OGN expression patterns and the clinical course of CRC, and the role of OGN in cancer progression.

Methods

The tissue microarray staining was performed and the relevance between OGN expression and oncologic outcomes was performed using Cox regression analysis. The effect of OGN on cell proliferation and tumorigenesis was examined in vitro and in vivo. Immunoprecipitation assay, immunofluorescence analysis and internalization assay were used for mechanistic study.

Results

Patients with high expression of OGN were associated with a profound longer survival in CRC and the high serum OGN level was also indicative of fewer recurrences consistently. In colon cancer cells, OGN increased dimerization of EGFR, then triggered EGFR endocytosis and induced the recruitment of downstream components of the EGFR internalization machinery (Eps15 and epsin1). Above all, OGN reduced Zeb-1 expression via EGFR/Akt leading to inhibition of epithelial-mesenchymal transition. As results, in vitro and in vivo, the OGN expression was demonstrated to reduce cell proliferation, inhibit invasion of colon cancer cells then impede cancer progression.

Conclusions

There is a positive association between OGN level and prolonged survival in CRC. OGN plays a restrictive role in colorectal cancer progression by reduced activation of EGFR/AKT/Zeb-1.

Overexpression of Pyruvate Dehydrogenase E1α Subunit Inhibits Warburg Effect and Induces Cell Apoptosis Through Mitochondria-Mediated Pathway in Hepatocellular Carcinoma

Most cancers rely disproportionately on glycolysis for energy even in the presence of an adequate oxygen supply, a condition known as “aerobic glycolysis,” or the “Warburg effect.” Pyruvate dehydrogenase E1α subunit (PDHA1) is one of the main factors for the metabolic switch from oxidative phosphorylation (OXPHOS) to aerobic glycolysis and has been suggested to be closely associated with tumorigenesis. Here we observed that the PDHA1 protein was reduced in hepatocellular carcinoma (HCC) specimens by immunohistochemistry and Western blot, which was significantly associated with poor overall survival. To further analyze the function of PDHA1 in cancer cells, PDHA1 was upregulated in the HCC cell lines SMMC-7721 and HepG2. The results demonstrated that overexpression of the PDHA1 gene inhibited aerobic glycolysis with lower lactate via increased PDH activity; meanwhile, mitochondrial OXPHOS was enhanced accompanied with higher ATP and lower glucose consumption. We also found that apoptosis was promoted and intrinsic pathway proteins were increased in PDHA1-overexpressing cells. Collectively, our data indicate that reduced PDHA1 protein expression is associated with the poor clinical outcome of HCC. Upregulated PDHA1 gene expression can inhibit the Warburg effect and enhance the mitochondria-mediated apoptosis pathway.

Exclusive inhibition of PI3K/Akt/mTOR signaling is not sufficient to prevent PDGF-mediated effects on glycolysis and proliferation in colorectal cancer

Platelet-derived growth factor (PDGF) and signaling via its receptors plays a crucial role in tumor cell proliferation and thus may represent an attractive target besides VEGF/EGFR-based antibody therapies. In this study we analyzed the influence of PDGF in colorectal cancer. PDGF was expressed intensively in early and even more intensively in late stage primary CRCs. Like VEGF, PDGF enhanced human colon cancer proliferation, and increased oxidative glycolytic activity, and activated HIF1α and c-Myc in vitro. PDGF activated the PI3K/Akt/mTOR pathway while leaving MAPK signaling untouched. Further dissection showed that inhibition of Akt strongly impeded cancer cell growth while inhibition of PI3K did not. MAPK analysis suggested an inhibitory crosstalk between both pathways, thus explaining the different effects of the Akt and PI3K inhibitors on cancer cell proliferation. PDGF stimulates colon cancer cell proliferation, and prevents inhibitor induced apoptosis, resulting in tumor growth. Therefore inhibition of PDGF signaling seems to be a promising target in colorectal cancer therapy. However, due to the multifaceted nature of the intracellular PDGF signaling, careful intervention strategies are needed when looking into specific signaling pathways like PI3K/Akt/mTOR and MAPK.