Downregulation of malic enzyme 3 facilitates progression of gastric carcinoma via regulating intracellular oxidative stress and hypoxia-inducible factor-1α stabilization.

BACKGROUND: Gastric cancer (GC) is one of the most malignant cancers worldwide. Metabolism disorder is a critical characteristic of malignant tumors related to tumor progression and metastasis. However, the expression and molecular mechanism of malic enzyme 3 (ME3) in GC are rarely reported. In this study, we aim to investigate the molecular mechanism of ME3 in the development of GC and to explore its potential value as a prognostic and therapeutic target in GC. METHOD: ME3 mRNA and protein expression were evaluated in patients with GC using RT-qPCR, WB, and immunohistochemistry, as well as their correlation with clinicopathological indicators. The effect of ME3 on proliferation and metastasis was evaluated using Cell Counting Kit-8 (CCK-8), 5-ethynyl-20-deoxyuridine (EdU) assay, transwell assay, wound healing assay, and subcutaneous injection or tail vein injection of tumor cells in mice model. The effects of ME3 knockdown on the level of metabolites and hypoxia-inducible factor-1α (HIF-1α) protein were determined in GC cells. Oxidative phosphorylation was measured to evaluate adenosine triphosphate (ATP) production. RESULTS: ME3 was downregulated in human GC tissues (P < 0.001). The decreased ME3 mRNA expression was associated with younger age (P = 0.02), pathological staging (P = 0.049), and lymph node metastasis (P = 0.001), while low ME3 expression was associated with tumor size (P = 0.048), tumor invasion depth (P < 0.001), lymph node metastasis (P = 0.018), TNM staging (P < 0.001), and poor prognosis (OS, P = 0.0206; PFS P = 0.0453). ME3 knockdown promoted GC cell malignancy phenotypes. Moreover, α-ketoglutarate (α-KG) and NADPH/NADP+ ratios were reduced while malate was increased in the ME3 knockdown group under normoxia. When cells were incubated under hypoxia, the NADPH/NADP+ ratio and α-KG decreased while intracellular reactive oxygen species (ROS) increased significantly. The ME3 knockdown group exhibited an increase in ATP production and while ME3 overexpression group exhibited oppositely. We discovered that ME3 and HIF-1α expression were negatively correlated in GC cells and tissues, and proposed the hypothesis: downregulation of ME3 promotes GC progression via regulating intracellular oxidative stress and HIF-1α. CONCLUSION: We provide evidence that ME3 downregulation is associated with poor prognosis in GC patients and propose a hypothesis for the ME3 regulatory mechanism in GC progression. The present study is of great scientific significance and clinical value for exploring the prognostic and therapeutic targets of GC, evaluating and improving the clinical efficacy of patients, reducing recurrence and metastasis, and improving the prognosis and quality of life of patients.

Deciphering the interaction between PKM2 and the built-in thermodynamic properties of the glycolytic pathway in cancer cells.

Most cancer cells exhibit high glycolysis rates under conditions of abundant oxygen. Maintaining a stable glycolytic rate is critical for cancer cell growth as it ensures sufficient conversion of glucose carbons to energy, biosynthesis, and redox balance. Here we deciphered the interaction between PKM2 and the thermodynamic properties of the glycolytic pathway. Knocking down or knocking out PKM2 induced a thermodynamic equilibration in the glycolytic pathway, characterized by the reciprocal changes of the Gibbs free energy (ΔG) of the reactions catalyzed by PFK1 and PK, leading to a less exergonic PFK1-catalyzed reaction and a more exergonic PK-catalyzed reaction. The changes in the ΔGs of the two reactions cause the accumulation of intermediates, including the substrate PEP (the substrate of PK), in the segment between PFK1 and PK. The increased concentration of PEP in turn increased PK activity in the glycolytic pathway. Thus, the interaction between PKM2 and the thermodynamic properties of the glycolytic pathway maintains the reciprocal relationship between PK concentration and its substrate PEP concentration, by which, PK activity in the glycolytic pathway can be stabilized and effectively counteracts the effect of PKM2 KD or KO on glycolytic rate. In line with our previous reports, this study further validates the roles of the thermodynamics of the glycolytic pathway in stabilizing glycolysis in cancer cells. Deciphering the interaction between glycolytic enzymes and the thermodynamics of the glycolytic pathway will promote a better understanding of the flux control of glycolysis in cancer cells.

Rapid and Green Fabrication of Nanozyme with Geminal CuN3O Configuration for Efficient Catecholase-Mimicking.

Fabrication of nanozyme with catecholase-like catalytic activity faces the great challenge of merging outstanding activity with low cost as well as simple, rapid, and low-energy-consumed production, restricting its industrial applications. Herein, an inexpensive yet robust nanozyme (i.e., DT-Cu) via simple one-step coordination between diaminotriazole (DT) and CuSO4 within 1 h in water at room temperature is constructed. The asymmetric dicopper site with CuN3O configuration for each copper as well as Cu─O bond length of ≈1.83 Å and Cu···Cu distance of ≈3.5 Å in DT-Cu resemble those in catechol oxidase (CO), which ensure its prominent intrinsic activity, outperforming most CO-mimicking nanozymes and artificial homogeneous catalysts. The use of inexpensive DT/CuSO4 in this one-pot strategy endows DT-Cu with only ≈20% cost of natural CO per activity unit. During catalysis, O2 experienced a 4e-dominated reduction process accompanied by the formation of 1O2 and H2O2 intermediates and the product of H2O. Benefiting from the low cost as well as the distinctive structure and superior intrinsic activity, DT-Cu presents potential applications ranging from biocatalysis to analytical detection of biomolecules such as epinephrine and beyond.

Type B3 thymoma complicated with Chlamydia psittaci pneumonia with rare features: A case report.

The case of a patient with type B3 thymomacomorbid with Chlamydia psittaci (C. psittaci) pneumonia exhibiting rare features is presented in the current report. The patient was admitted at the Second Affiliated Hospital of Jiaxing University (Jiaxing, China) with a history of direct contact with poultry. Clinical manifestations included fever, shivers, cough, fatigue and poor appetite. Chest computed tomography (CT) indicated right lung pneumonia, while metagenomics next-generation sequencing using bronchoalveolar lavage fluid confirmed infection with C. psittaci. Additionally, positron emission tomography-CT suggested the presence of thymoma. After surgery and treatment with doxycycline and imipenem cilastatin, the patient was discharged showing signs of improvement.

Retraction: The lncRNA XIST/miR-29b-3p/COL3A1 axis regulates central carbon metabolism in head and neck squamous cell carcinoma and is associated with poor tumor prognosis.

[This retracts the article DOI: 10.21037/atm-23-30.].

Hallmark guided identification and characterization of a novel immune-relevant signature for prognostication of recurrence in stage I-III lung adenocarcinoma.

The high risk of postoperative mortality in lung adenocarcinoma (LUAD) patients is principally driven by cancer recurrence and low response rates to adjuvant treatment. Here, A combined cohort containing 1,026 stage I-III patients was divided into the learning (n = 678) and validation datasets (n = 348). The former was used to establish a 16-mRNA risk signature for recurrence prediction with multiple statistical algorithms, which was verified in the validation set. Univariate and multivariate analyses confirmed it as an independent indicator for both recurrence-free survival (RFS) and overall survival (OS). Distinct molecular characteristics between the two groups including genomic alterations, and hallmark pathways were comprehensively analyzed. Remarkably, the classifier was tightly linked to immune infiltrations, highlighting the critical role of immune surveillance in prolonging survival for LUAD. Moreover, the classifier was a valuable predictor for therapeutic responses in patients, and the low-risk group was more likely to yield clinical benefits from immunotherapy. A transcription factor regulatory protein-protein interaction network (TF-PPI-network) was constructed via weighted gene co-expression network analysis (WGCNA) concerning the hub genes of the signature. The constructed multidimensional nomogram dramatically increased the predictive accuracy. Therefore, our signature provides a forceful basis for individualized LUAD management with promising potential implications.

Lactic acidosis switches cancer cells from dependence on glycolysis to OXPHOS and renders them highly sensitive to OXPHOS inhibitors.

Targeting oxidative phosphorylation (OXPHOS) has emerged as a strategy for cancer treatment. However, most tumor cells exhibit Warburg effect, they primarily rely on glycolysis to generate ATP, and hence they are resistant to OXPHOS inhibitors. Here, we report that lactic acidosis, a ubiquitous factor in the tumor microenvironment, increases the sensitivity of glycolysis-dependent cancer cells to OXPHOS inhibitors by 2-4 orders of magnitude. Lactic acidosis reduces glycolysis by 79-86% and increases OXPHOS by 177-218%, making the latter the main production pathway of ATP. In conclusion, we revealed that lactic acidosis renders cancer cells with typical Warburg effect phenotype highly sensitive to OXPHOS inhibitors, thereby greatly expanding the anti-cancer spectrum of OXPHOS inhibitors. In addition, as lactic acidosis is a ubiquitous factor of TME, it is a potential indicator to predict the efficacy of OXPHOS inhibitors in cancer treatment.

Expression Levels of MicroRNA-300/BCL2L11 in Papillary Thyroid Cancer and Their Clinical Diagnostic Values.

INTRODUCTION: This research aims to explore the expression levels of microRNA (miRNA)-300/BCL-2-like protein 11 (BCL2L11) and their values in the clinical diagnosis of papillary thyroid cancer (PTC). METHODS: Pathological tissues that were surgically removed for thyroid disease were selected. miR-300 and BCL2L11 expression levels in the samples were measured. Receiver operating characteristic (ROC) curves were plotted to analyze miR-300 and BCL2L11 predictive values for PTC. Upon silencing miR-300 and silencing BCL2L11 in PTC cells, the corresponding miR-300 and BCL2L11 expression levels were tested, followed by examining PTC cell activities. The targeting relationship of miR-300 and BCL2L11 was detected by the bioinformatics website and luciferase activity assay. RESULTS: miR-300 expression levels were elevated and BCL2L11 expression levels were reduced in PTC tissues. miR-300 and BCL2L11 expression levels in PTC tissues had a correlation with TNM stage and lymph node metastasis. The results of ROC curve revealed that both miR-300 and BCL2L11 had clinical predictive values for PTC. Mechanistically, miR-300 negatively regulated BCL2L11. The functional assays unveiled that silencing miR-300 impeded PTC cell activities, and silencing BCL2L11 induced PTC cell activities. In the rescue experiment, silencing BCL2L11 reversed the impacts of silencing miR-300 on PTC cell development. CONCLUSION: This study underlines that miR-300 expression is increased and BCL2L11 expression is declined in PTC. miR-300 and BCL2L11 both have clinical predictive values for diagnosing PTC.

Extracorporeal membrane oxygenation combined with minimally invasive surgery for acute respiratory failure and sudden cardiac arrest: A case report.

Acute respiratory failure and sudden cardiac arrest caused by acute intrathoracic infection is a fatal clinical condition with a low resuscitation success rate. The present study describes the case of a patient with acute empyema secondary to an acute lung abscess rupture, complicated by acute respiratory failure and sudden cardiac arrest caused by severe hypoxemia. The patient recovered well through the administration of multiple therapeutic measures, including medication and closed chest drainage, cardiopulmonary resuscitation, extracorporeal membrane oxygenation combined with continuous renal replacement therapy, and minimally invasive surgical resection of the lung lesion with persistent alveolar fistula as the clinical manifestation. To the best of our knowledge, the treatment of such a severe condition combined with thoracoscopic surgery has rarely been reported before, and the present study may provide insight regarding therapeutic schedules for acute respiratory failure by intrathoracic infection, and excision of ruptured lung abscess.

Single-Molecule Force Spectroscopy of Deoxyribonucleic Acid and Deoxyribonucleic Acid Polymerase Activity Impacted by Alkylating Agents.

DNA alkylating agents are widely used in anticancer pharmacology. Although shown to induce cross-linking and/or methylation of DNA, how they affect the mechanical properties of DNA and activity of DNA enzymes remains to be elucidated. Here, we perform single-molecule optical tweezer experiments on DNA treated with alkylating agents, including melphalan, cisplatin, and dacarbazine. While all three drugs induce a significant increase of overstretching force and a reduction of hysteresis, suggesting stabilization of DNA against shearing forces, their effects on elasticity of DNA were quite different, with the largest change in persistence length induced by cisplatin. Furthermore, we find that these alkylating-agent-induced changes on DNA have different effects on processivity of DNA polymerase, with melphalan and cisplatin showing significantly reduced activity and dacarbazine showing little effect. Overall, our results provide new insights into the effects for these alkylating agents, which could potentially facilitate a better design of related drugs.

The lncRNA XIST/miR-29b-3p/COL3A1 axis regulates central carbon metabolism in head and neck squamous cell carcinoma and is associated with poor tumor prognosis.

Background: Recent evidence shows that COL3A1 promotes the progression of many types of cancer. The purpose of our study is to explore the correlation between COL3A1 and the prognosis of patients with head and neck squamous cell carcinoma (HNSCC) and its potential mechanism. Methods: We initially screened the differentially expressed gene COL3A1 in The Cancer Genome Atlas (TCGA) database, and the association between the expression level of COL3A1, prognosis, and the clinical parameters of HNSCC patients was verified. A nomogram was constructed according to the multivariate analysis results. Next, a heatmap of COL3A1 co-expressed genes was constructed in TCGA database. The TargetScan database is used to explore the microRNAs (miRNA) related to COL3A1. The starBase database was used to explore and predict the long non-coding RNAs (lncRNAs) that the candidate miRNAs might bind to. Finally, the potential mechanism of action was investigated using Gene Set Enrichment Analysis (GSEA). Results: COL3A1 expression is elevated in HNSCC tumor tissues, and HNSCC patients with high COL3A1 expression have worse prognostic factors. COL3A1 was positively correlated with the central carbon metabolism-related proteins: epidermal growth factor receptor (EGFR), phosphoglycerate mutase 1 (PGAM1), hexokinase 3 (HK3), and phosphofructokinase, platelet (PFKP). The TargetScan database showed that the best candidate miRNA for binding to the three prime untranslated region (3'UTR) end of COL3A1 mRNA was hsa-miR-29b-3p, which was negatively correlated with COL3A1. The starBase database showed that the lncRNA X Inactive Specific Transcript (lncRNA XIST) was the best candidate upstream non-coding RNA for regulating hsa-miR-29b-3p. GSEA showed that COL3A1 may be involved in the poor prognosis of HNSCC by participating in carbon metabolism, glucose metabolism, oxidative stress, and the Wingless-Type MMTV Integration Site Family (Wnt) and vascular endothelial growth factor A-vascular endothelial growth factor receptor 2 (VEGFA-VEGFR2) pathways. Conclusions: Low COL3A1 expression can be employed as a new HNSCC predictive biomarker, and the prognosis of HNSCC patients with lower COL3A1 expression can be greatly improved. At the same time, we found that the lncRNA XIST/miR-29b-3p/COL3A1 axis may regulate the central carbon metabolism of HNSCC and is associated with poor prognosis. These findings point to a potential target for developing HNSCC anticancer therapies.

Bioinformatics based exploration of hsa-miR-194-5p regulation of CHD4 through PI3K/AKT signal pathway to enhance tumor resistance to apoptosis due to loss of nests and participate in poor prognosis of oral squamous cell carcinoma.

Background: Recent evidence shows that CHD4 is involved in a variety of biological events of tumors. Our aim was to investigate the correlation between CHD4 and oral squamous cell carcinoma (OSCC). Methods: After CHD4 was screened as a differentially expressed gene in The Cancer Genome Atlas (TGCA) database, the correlations of its expression level with the clinical parameters and prognosis of patients with OSCC were analyzed. The outcomes of the multivariate analysis were used to construct a nomogram, and the accuracy of the model was evaluated with the calibration curve. The GeneMANIA and STRING databases were used to generate network diagrams depicting interactions of genes with CHD4, and heat maps of genes co-expressed with CHD4 were generated using the TCGA database. TargetScan was then used to look into the miRNAs that interact with the 3' untranslated region of CHD4 mRNA. Finally, GSEA enrichment analysis was used to explore the possible mechanism. Results: The differentially expressed molecule CHD4 was screened by TCGA database for OSCC. CHD4 was overexpressed in OSCC tumor tissues, and OSCC patients with low expression of CHD4 have better OS and DSS. The nomogram had a C-index of 0.575 (0.548-0.602), which indicated some degree of predictive reliability. CHD4 has certain correlation with exons of OSCC related genes, including TP53, NOTCH1, CASP8, PTEN, TP63, ANXA1, CDH1, CTNNB1, GDF15 and EGFR. According to the TargetScan database, hsa-miR-194-5p is the miRNA that regulates CHD4 upstream the most. GSEA analysis showed that CHD4 may participate in the poor prognosis of OSCC by participating in PI3K/AKT pathway, protein adhesion regulation, MAPK pathway, cytokine and inflammatory response regulation, angiogenesis and platelet regulation. Conclusions: The decreased expression of CHD4 may indicate a better prognosis in OSCC patients and could serve as a novel predictive biomarker for OSCC. Also, hsa-miR-194-5p was found to contribute to the poor prognosis of OSCC by regulating CHD4 and enhancing tumor anoikis resistance via the PI3K/AKT signaling pathway. These findings suggest that CHD4 might be a therapeutic target for the effective treatment of OSCC.

Understanding real-world treatment patterns and clinical outcomes in AL amyloidosis patients diagnosed in Canada: A population-based cohort study.

Amyloid light chain (AL) amyloidosis is a rare and chronic bone marrow disorder. Existing claims data can be used to help understand the real-world treatment patterns and outcomes of this patient population. Various population-based administrative databases in Alberta, Canada were queried from 2010 to mid-2019 to identify cases of AL amyloidosis. Baseline patient and disease characteristics, sequencing of pharmacologic therapies, overall survival, and healthcare resource utilization were evaluated. A total of 215 individuals with AL amyloidosis were included. Among patients diagnosed between 2012 and 2019, 149 (85.1%) initiated first-line, 67 (38.3%) initiated second-line, 22 (12.6%) initiated third-line, and 11 (6.3%) initiated fourth-line systemic therapy. In the first-line setting, 99/149 (66.4%) received bortezomib, cyclophosphamide, and dexamethasone (CyBorD) and 21/149 (14.1%) received another bortezomib-based regimen. Survival from time of diagnosis improved over time, with a median overall survival of 25.8 months (95% CI: 9.8, 57.1) for individuals diagnosed in 2010-2011 versus 52.1 months (95% CI: 25.6, NA) for those diagnosed in 2012-2019. Despite this improvement, the proportion of individuals diagnosed in 2012-2019 who survived beyond five-years remained low (5-year survival: 48.4%; 95% CI: 40.9, 57.2) which highlights an unmet need for more efficacious therapies.

Leukocyte CH25H is a potential diagnostic and prognostic marker for lung adenocarcinoma.

Metastasis, a major challenge during the treatment of lung cancer, causes deterioration in patient health outcomes. Thus, to address this problem, this study aimed to explore the role and contribution of Cholesterol 25-Hydroxylase (CH25H) as a potential diagnostic and prognostic marker in lung cancer. Online public databases were used to analyze the expression level, prognostic value, gene-pathway enrichment, and immune infiltration of CH25H in lung cancer patients. The Real-Time Quantitative Reverse Transcription PCR (qRT-PCR) was used to analyze and detect the CH25H expression levels in leukocytes from lung cancer patients. The expression level of CH25H was significantly reduced in lung adenocarcinoma (LUAD), which is associated with a higher disease stage, but not in lung squamous cell carcinoma (LUSC). Kaplan-Meier survival analysis indicated that LUAD patients with low CH25H expression had a worse prognosis. Mechanistically, our results showed that in LUAD, CH25H may be a regulatory factor affecting the immune cell infiltration level, and the resultant tumor development. Experimental data showed that low expression of CH25H in leukocytes was significantly associated with LUAD metastasis (P < 0.01). Our study suggests that CH25H may function as a prognostic and risk stratification biomarker for LUAD.

Alloying nickel and cobalt with iron on ZSM-5 for tuning competitive hydrogenation reactions for selective one-pot conversion of furfural to gamma-valerolactone.

One-pot conversion of furfural, a biomass-derived platform chemical, to gamma-valerolactone (GVL), a fuel additive and green solvent, involves multiple steps of hydrogenation. Among these reactions, the deep hydrogenation of the furan ring in furfural interrupts GVL formation over Ni or Co-based catalysts. In this study, a method of alloying Ni and Co with Fe over a ZSM-5 support was proposed for tackling excessive activity of the catalyst for hydrogenation. The results indicated that the formation of binary NiFe and CoFe alloys in Ni-Co-Fe/ZSM-5 enhanced the dispersion of metallic species, reduction of metal oxides, formation of more Lewis acidic sites, and the adsorption of the C-O functionality of the furan ring, while lowering the capability for adsorption/activation of H2 and the adsorption of the CC group of the furan ring. These factors together reduced the activity for the hydrogenation of the furan ring in furfural, but enhanced the hydrogenation of the CO in ethyl levulinate (EL). The kinetic study confirmed that the hydrogenation of EL was the rate-determining step. The coordination of the dual alloys, NiFe and CoFe, in the bifunctional Ni-Co-Fe/ZSM-5 catalyst rendered superior activity for selective one-pot conversion of furfural to GVL with a yield of 85.7%.

Tracing the electron flow in redox metabolism: The appropriate distribution of electrons is essential to maintain redox balance in cancer cells.

Cancer cells are characterized by sustained proliferation, which requires a huge demand of fuels to support energy production and biosynthesis. Energy is produced by the oxidation of the fuels during catabolism, and biosynthesis is achieved by the reduction of smaller units or precursors. Therefore, the oxidation-reduction (redox) reactions in cancer cells are more active compared to those in the normal counterparts. The higher activity of redox metabolism also induces a more severe oxidative stress, raising the question of how cancer cells maintain the redox balance. In this review, we overview the redox metabolism of cancer cells in an electron-tracing view. The electrons are derived from the nutrients in the tumor microenvironment and released during catabolism. Most of the electrons are transferred to NAD(P) system and then directed to four destinations: energy production, ROS generation, reductive biosynthesis and antioxidant system. The appropriate distribution of these electrons achieved by the function of redox regulation network is essential to maintain redox homeostasis in cancer cells. Interfering with the electron distribution and disrupting redox balance by targeting the redox regulation network may provide therapeutic implications for cancer treatment.

The Prospective Implementation of the 2015 ATA Guidelines and Modified ATA Recurrence Risk Stratification System for Treatment of Differentiated Thyroid Cancer in a Canadian Tertiary Care Referral Setting.

Objective: To present clinical outcomes of the prospective implementation of the 2015 American Thyroid Association (ATA) guidelines for the management of thyroid nodules and differentiated thyroid cancer (DTC) using the modified ATA recurrence risk (RR) stratification system. Methods: We prospectively analyzed 612 patients with DTC treated between April 2017 and December 2021 in Calgary, Alberta. Each patient was prospectively assigned a modified ATA RR and American Joint Committee Cancer 8th edition stage. Initial risk stratification and consideration of the 2015 ATA guidelines guided surgical management as well as the indication for and dose of radioiodine (RAI) and other adjuvant therapies. Patients were assessed for their response to treatment (RTT) at 2-years postoperatively. Results: There were 479 patients who had 2-year follow-up data and were included in the study. Of these patients, there were 253 (53%) low-, 129 (27%) intermediate-, and 97 (20%) high-RR patients. Of these, 227 patients (47%) underwent total thyroidectomy (TTX) plus RAI, 178 (37%) underwent TTX only, and 74 (16%) underwent lobectomy. The RTT at 2 years was excellent for 89% (66) of patients with lobectomy, 84% (149) for TTX only, and 53% (121) for TTX plus RAI. Among 253 patients who were deemed low RR, 85% (216) had excellent RTT, 13% (32) indeterminate RTT, 2% (4) biochemical incomplete RTT, and 1 patient had structural incomplete RTT. The intermediate RR group had the following RTT outcomes: 64% (83) excellent, 23% (30) indeterminate, 6% (7) biochemical incomplete, and 7% (9) structural incomplete. The high RR group had the worst RTT outcomes, with 38% (37) excellent, 19% (18) indeterminate, 10% (10) biochemical incomplete, and 33% (32) structural incomplete RTT. Conclusions: The 2015 ATA RR stratification system is useful for predicting disease status at 2-year post-treatment in patients with DTC. The 2015 ATA guidelines and modified ATA RR stratification treatment recommendations may reduce thyroid cancer overtreatment by including lobectomy as a definitive treatment option for low-risk thyroid cancers and selective use of RAI for intermediate and high-risk patients.