RESUMEN
Electrochemical hydrogenation of aldehyde molecules, exemplified by 5-hydroxymethylfurfural (HMF), offers a sustainable approach for synthesizing higher value-added alcohols. However, severe coupling side reactions impede its practical implementation at high concentrations. In this work, a cluster-level heterostructure of a PMo12/Cu catalyst is synthesized by loading Keggin-type phosphomolybdic acid (H3PMo12O40, PMo12) onto Cu nanowires. The catalyst exhibits high selectivity in electrocatalytic hydrogenation (ECH) of HMF to 2,5-bishydroxymethylfuran (BHMF) under an unprecedentedly high substrate concentration of 1.0 M. Under -0.3 V (vs RHE) with 1.0 M HMF, PMo12/Cu shows a Faradaic efficiency as high as 98% with an excellent productivity of 4.35 mmol cm-2 h-1 toward BHMF, much higher than those on the pristine Cu nanowires. Mechanism studies and density functional theory calculations demonstrate that the heterostructural interface of PMo12/Cu serves as an active reaction center for the ECH. The unique electronic properties and geometric structure promote the dissociative reduction of water molecules to generate H* and reduce HMF with a decreased reaction energy barrier, which is responsible for exceptional reactivity and selectivity.
RESUMEN
A variety of malignancies preferentially meet energy demands through the glycolytic pathway. Hypoxiainduced cancer cell adaptations are essential for tumor development. However, in cancerous glycolysis, the functional importance and underlying molecular mechanism of prolyl hydroxylase domain protein 2 (PHD2) have not been fully elucidated. Gain and lossoffunction assays were conducted to evaluate PHD2 functions in colon cancer cells. Glucose uptake, lactate production and intracellular adenosine5'triphosphate/adenosine diphosphate ratio were measured to determine glycolytic activities. Protein and gene expression levels were measured by western blot analysis and reverse transcriptionquantitative PCR, respectively. The human colon cancer xenograft model was used to confirm the role of PHD2 in tumor progression in vivo. Functionally, the data demonstrated that PHD2 knockdown leads to increased glycolysis, while PHD2 overexpression resulted in suppressed glycolysis in colorectal cancer cells. In addition, the glycolytic activity was enhanced without PHD2 and normalized after PHD2 reconstitution. PHD2 was shown to inhibit colorectal tumor growth, suppress cancer cell proliferation and improve tumorbearing mice survival in vivo. Mechanically, it was found that PHD2 inhibits the expression of critical glycolytic enzymes (glucose transporter 1, hexokinase 2 and phosphoinositidedependent protein kinase 1). In addition, PHD2 inhibited Ikkßmediated NFκB activation in a hypoxiainducible factor1αindependent manner. In conclusion, the data demonstrated that PHD2/Ikkß/NFκB signaling has critical roles in regulating glycolysis and suggests that PHD2 potentially suppresses colorectal cancer.
Asunto(s)
Neoplasias del Colon , Neoplasias Colorrectales , Animales , Humanos , Ratones , Línea Celular Tumoral , Neoplasias Colorrectales/patología , Glucólisis , Prolina Dioxigenasas del Factor Inducible por Hipoxia/genética , Prolina Dioxigenasas del Factor Inducible por Hipoxia/metabolismo , Quinasa I-kappa B/metabolismo , FN-kappa B/genética , FN-kappa B/metabolismo , Procolágeno-Prolina Dioxigenasa/metabolismo , Prolil Hidroxilasas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de SeñalRESUMEN
BACKGROUND: Liquid biopsies, for example, exosomal circular RNA (circRNA) can be used to assess potential predictive markers for hepatocellular carcinoma (HCC) in patients after curative resection. This study aimed to search for effective prognostic biomarkers for HCC in patients after surgical resection based on exosomal circRNA expression profiles. We developed two nomograms incorporating circRNAs to predict the postoperative recurrence-free survival (RFS) and overall survival (OS) of HCC patients. METHOD: Plasma exosomes isolated from HCC patients and healthy individuals were used for circRNA microarray analysis to explore differentially expressed circRNAs. Pearson correlation analysis was used to evaluate the correlation between circRNAs and clinicopathological features. Cox regression analysis was used to explore the correlation between circRNA and postoperative survival time as well as recurrence time. A nomogram based on circRNA and clinicopathological characteristics was established and further evaluated to predict prognosis and recurrence. RESULT: Among 60 significantly upregulated circRNAs and 25 downregulated circRNAs, hsa_circ_0029325 was selected to verify its power for predicting HCC outcomes. The high expression level of exosomal hsa_circ_0029325 was significantly correlated with OS (P = 0.001, HR = 2.04, 95% CI 1.41-3.32) and RFS (P = 0.009, HR = 1.62, 95% CI 1.14-2.30). Among 273 HCC patients, multivariate regression analysis showed that hsa_circ_0029325 (HR = 1.96, 95% CI 1.21-3.18), tumor size (HR = 2.11, 95% CI 1.33-3.32), clinical staging (HR = 2.31, 95% CI 1.54-3.48), and tumor thrombus (HR = 1.74, 95% CI 1.12-2.7) were independent risk factors for poor prognosis in HCC patients after radical resection. These independent predictors of prognosis were incorporated into the two nomograms. The AUCs under the 1-year, 3-year, and 5-year survival and recurrence curves of the OS and RFS nomograms were 0.755, 0.749, and 0.742 and 0.702, 0.685, and 0.642, respectively. The C-index, calibration curves, and clinical decision curves showed that the two prediction models had good predictive performance. These results were verified in the validation cohort with 90 HCC patients. CONCLUSION: Our study established two reliable nomograms for predicting recurrence and prognosis in HCC patients. We also show that it is feasible to screen potential predictive markers for HCC after curative resection through exosomal circRNA expression profile analysis.