ABSTRACT
Respiratory syncytial virus (RSV) is one of the leading causes of viral respiratory tract infection in infants, the elderly, and the immunocompromised worldwide, causing more deaths each year than influenza. Years of research into RSV since its discovery over 60 yr ago have elucidated detailed mechanisms of the host-pathogen interface. RSV infection elicits widespread transcriptomic and proteomic changes, which both mediate the host innate and adaptive immune responses to infection, and reflect RSV's ability to circumvent the host stress responses, including stress granule formation, endoplasmic reticulum stress, oxidative stress, and programmed cell death. The combination of these events can severely impact on human lungs, resulting in airway remodeling and pathophysiology. The RSV membrane envelope glycoproteins (fusion F and attachment G), matrix (M) and nonstructural (NS) 1 and 2 proteins play key roles in modulating host cell functions to promote the infectious cycle. This review presents a comprehensive overview of how RSV impacts the host response to infection and how detailed knowledge of the mechanisms thereof can inform the development of new approaches to develop RSV vaccines and therapeutics.
Subject(s)
Antiviral Agents/pharmacology , Respiratory Syncytial Virus Infections/prevention & control , Respiratory Syncytial Virus Infections/virology , Respiratory Syncytial Virus, Human , Viral Vaccines/immunology , Humans , Respiratory Syncytial Virus Infections/drug therapy , Respiratory Syncytial Virus Infections/immunologyABSTRACT
Despite its success in achieving the long-term survival of 10-30% of treated individuals, immune therapy is still ineffective for most patients with cancer1,2. Many efforts are therefore underway to identify new approaches that enhance such immune 'checkpoint' therapy3-5 (so called because its aim is to block proteins that inhibit checkpoint signalling pathways in T cells, thereby freeing those immune cells to target cancer cells). Here we show that inhibiting PCSK9-a key protein in the regulation of cholesterol metabolism6-8-can boost the response of tumours to immune checkpoint therapy, through a mechanism that is independent of PCSK9's cholesterol-regulating functions. Deleting the PCSK9 gene in mouse cancer cells substantially attenuates or prevents their growth in mice in a manner that depends on cytotoxic T cells. It also enhances the efficacy of immune therapy that is targeted at the checkpoint protein PD1. Furthermore, clinically approved PCSK9-neutralizing antibodies synergize with anti-PD1 therapy in suppressing tumour growth in mouse models of cancer. Inhibiting PCSK9-either through genetic deletion or using PCSK9 antibodies-increases the expression of major histocompatibility protein class I (MHC I) proteins on the tumour cell surface, promoting robust intratumoral infiltration of cytotoxic T cells. Mechanistically, we find that PCSK9 can disrupt the recycling of MHC I to the cell surface by associating with it physically and promoting its relocation and degradation in the lysosome. Together, these results suggest that inhibiting PCSK9 is a promising way to enhance immune checkpoint therapy for cancer.
Subject(s)
Immune Checkpoint Inhibitors/pharmacology , Immune Checkpoint Inhibitors/therapeutic use , Immunotherapy/methods , Neoplasms/drug therapy , Neoplasms/immunology , PCSK9 Inhibitors , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Animals , Antibodies, Neutralizing/immunology , Antibodies, Neutralizing/pharmacology , Antibodies, Neutralizing/therapeutic use , Cell Line, Tumor , Disease Models, Animal , Female , Histocompatibility Antigens Class I/immunology , Histocompatibility Antigens Class I/metabolism , Humans , Lysosomes/metabolism , Mice , Neoplasms/metabolism , Neoplasms/pathology , Proprotein Convertase 9/deficiency , Proprotein Convertase 9/genetics , Proprotein Convertase 9/immunology , T-Lymphocytes, Cytotoxic/cytology , T-Lymphocytes, Cytotoxic/immunology , Xenograft Model Antitumor AssaysABSTRACT
Mitochondria play an integral role in cell death, autophagy, immunity, and inflammation. We previously showed that Nur77, an orphan nuclear receptor, induces apoptosis by targeting mitochondria. Here, we report that celastrol, a potent anti-inflammatory pentacyclic triterpene, binds Nur77 to inhibit inflammation and induce autophagy in a Nur77-dependent manner. Celastrol promotes Nur77 translocation from the nucleus to mitochondria, where it interacts with tumor necrosis factor receptor-associated factor 2 (TRAF2), a scaffold protein and E3 ubiquitin ligase important for inflammatory signaling. The interaction is mediated by an LxxLL motif in TRAF2 and results not only in the inhibition of TRAF2 ubiquitination but also in Lys63-linked Nur77 ubiquitination. Under inflammatory conditions, ubiquitinated Nur77 resides at mitochondria, rendering them sensitive to autophagy, an event involving Nur77 interaction with p62/SQSTM1. Together, our results identify Nur77 as a critical intracellular target for celastrol and unravel a mechanism of Nur77-dependent clearance of inflamed mitochondria to alleviate inflammation.
Subject(s)
Anti-Inflammatory Agents/pharmacology , Autophagy/drug effects , Chemical and Drug Induced Liver Injury/prevention & control , Mitochondria, Liver/drug effects , Mitophagy/drug effects , Nuclear Receptor Subfamily 4, Group A, Member 1/metabolism , TNF Receptor-Associated Factor 2/metabolism , Triterpenes/pharmacology , Ubiquitination/drug effects , Active Transport, Cell Nucleus , Animals , Anti-Inflammatory Agents/metabolism , Chemical and Drug Induced Liver Injury/genetics , Chemical and Drug Induced Liver Injury/metabolism , Disease Models, Animal , Female , Genotype , HEK293 Cells , HeLa Cells , Hep G2 Cells , Humans , Ligands , Male , Mice, Inbred C57BL , Mice, Knockout , Mitochondria, Liver/metabolism , Mitochondria, Liver/pathology , Nuclear Receptor Subfamily 4, Group A, Member 1/deficiency , Nuclear Receptor Subfamily 4, Group A, Member 1/genetics , Pentacyclic Triterpenes , Phenotype , Protein Binding , Protein Interaction Domains and Motifs , RNA Interference , Sequestosome-1 Protein/genetics , Sequestosome-1 Protein/metabolism , Signal Transduction/drug effects , TNF Receptor-Associated Factor 2/genetics , Transfection , Triterpenes/metabolismABSTRACT
BACKGROUND AND AIMS: Sexually transmitted infections (STIs) are a significant global public health challenge due to their high incidence rate and potential for severe consequences when early intervention is neglected. Research shows an upward trend in absolute cases and DALY numbers of STIs, with syphilis, chlamydia, trichomoniasis, and genital herpes exhibiting an increasing trend in age-standardized rate (ASR) from 2010 to 2019. Machine learning (ML) presents significant advantages in disease prediction, with several studies exploring its potential for STI prediction. The objective of this study is to build males-based and females-based STI risk prediction models based on the CatBoost algorithm using data from the National Health and Nutrition Examination Survey (NHANES) for training and validation, with sub-group analysis performed on each STI. The female sub-group also includes human papilloma virus (HPV) infection. METHODS: The study utilized data from the National Health and Nutrition Examination Survey (NHANES) program to build males-based and females-based STI risk prediction models using the CatBoost algorithm. Data was collected from 12,053 participants aged 18 to 59 years old, with general demographic characteristics and sexual behavior questionnaire responses included as features. The Adaptive Synthetic Sampling Approach (ADASYN) algorithm was used to address data imbalance, and 15 machine learning algorithms were evaluated before ultimately selecting the CatBoost algorithm. The SHAP method was employed to enhance interpretability by identifying feature importance in the model's STIs risk prediction. RESULTS: The CatBoost classifier achieved AUC values of 0.9995, 0.9948, 0.9923, and 0.9996 and 0.9769 for predicting chlamydia, genital herpes, genital warts, gonorrhea, and overall STIs infections among males. The CatBoost classifier achieved AUC values of 0.9971, 0.972, 0.9765, 1, 0.9485 and 0.8819 for predicting chlamydia, genital herpes, genital warts, gonorrhea, HPV and overall STIs infections among females. The characteristics of having sex with new partner/year, times having sex without condom/year, and the number of female vaginal sex partners/lifetime have been identified as the top three significant predictors for the overall risk of male STIs. Similarly, ever having anal sex with a man, age and the number of male vaginal sex partners/lifetime have been identified as the top three significant predictors for the overall risk of female STIs. CONCLUSIONS: This study demonstrated the effectiveness of the CatBoost classifier in predicting STI risks among both male and female populations. The SHAP algorithm revealed key predictors for each infection, highlighting consistent demographic characteristics and sexual behaviors across different STIs. These insights can guide targeted prevention strategies and interventions to alleviate the impact of STIs on public health.
Subject(s)
Gonorrhea , Herpes Genitalis , Papillomavirus Infections , Sexually Transmitted Diseases , Warts , Female , Male , Humans , Adolescent , Young Adult , Adult , Middle Aged , Nutrition Surveys , Sexually Transmitted Diseases/epidemiology , AlgorithmsABSTRACT
Monitoring etoposide is important due to its wide usage in anti-tumor therapy; however, the commonly used HPLC method is expensive and often requires complicated extraction and detection procedures. Electrochemical analysis has great application prospects because of its rapid response and high specificity, sensitivity, and efficiency with low cost and high convenience. In this study, we constructed a nanoporous gold (NPG)-modified GCE for the detection of etoposide. The electrochemical oxidation of etoposide by NPG caused a sensitive current peak at +0.27 V with good reproductivity in 50 mM of phosphate buffer (pH 7.4). The relationship between etoposide concentration and peak current was linear in the range between 0.1 and 20 µM and between 20 and 150 µM, with a detection sensitivity of 681.8 µA mM-1 cm-2 and 197.2 µA mM-1 cm-2, respectively, and a limit of detection (LOD) reaching 20 nM. The electrode had a good anti-interference ability to several common anions and cations. Spiked recovery tests in serum, urine, and fermentation broth verified the excellent performance of the sensor in terms of sensitivity, reproducibility, and specificity. This may provide a promising tool for the detection of etoposide in biological samples.
Subject(s)
Antineoplastic Agents , Nanopores , Etoposide , Gold , Reproducibility of Results , Electrochemical Techniques/methods , ElectrodesABSTRACT
Owing to its unique physical properties, fluorine is often used to open up new reaction channels. In this report, we establish a cooperation of [5,5]-rearrangement and fluorine-assisted temporary dearomatization for arene multi-functionalization. Specifically, the [5,5]-rearrangement of fluoroaryl sulfoxides with ß,γ-unsaturated nitriles generates an intriguing dearomatized sulfonium species which is short-lived but exhibits unusually high electrophilicity and thus can be instantly trapped by nucleophiles and dienes at a remarkably low temperature (-95 °C) to produce four types of valuable multi-functionalized benzenes, respectively, involving appealing processes of defluorination, desulfurization, and sulfur shift. Mechanistic studies indicate that the use of fluorine on arenes not only circumvents the generally inevitable [3,3]-rearrangement but also impedes the undesired rearomatization process, thus provides a precious space for constructing and elaborating the temporarily dearomatized fluorinated sulfonium species.
ABSTRACT
OBJECTIVES: The study was to develop a Gd-EOB-DTPA-enhanced MRI radiomics model for preoperative prediction of VETC and patient prognosis in hepatocellular cancer (HCC). METHODS: The study included 182 (training cohort: 128; validation cohort: 54) HCC patients who underwent preoperative Gd-EOB-DTPA-enhanced MRI. Volumes of interest including intratumoral and peritumoral regions were manually delineated in the hepatobiliary phase images, from which 1316 radiomics features were extracted. The least absolute shrinkage and selection operator (LASSO) and multivariable logistic regression were used to select the useful features. Clinical, intratumoral, peritumoral, combined radiomics, and clinical radiomics models were established using machine learning algorithms. The Kaplan-Meier survival analysis was used to assess early recurrence and progression-free survival (PFS) in the VETC + and VETC- patients. RESULTS: In the validation cohort, the area under the curves (AUCs) of radiomics models were higher than that of the clinical model using random forest (all p < 0.05). The peritumoral radiomics model (AUC = 0.972;95% confidence interval [CI]:0.887-0.998) had significantly higher AUC than intratumoral model (AUC = 0.919; 95% CI: 0.811-0.976) (p = 0.044). There were no significant differences in AUC between intratumoral or peritumoral radiomics model (PR) and combined radiomics model (p > 0.05). Early recurrence and PFS were significantly different between the PR-predicted VETC + and VETC- HCC patients (p < 0.05). PR-predicted VETC was independent predictor of early recurrence (hazard ratio [HR]: 2.08[1.31-3.28]; p = 0.002) and PFS (HR: 1.95[1.20-3.17]; p = 0.007). CONCLUSIONS: The intratumoral or peritumoral radiomics model may be useful in predicting VETC and patient prognosis preoperatively. The peritumoral radiomics model may yield an incremental value over intratumoral model. KEY POINTS: ⢠Radiomics models are useful for predicting vessels encapsulating tumor clusters (VETC) and patient prognosis preoperatively. ⢠Peritumoral radiomics model may yield an incremental value over intratumoral model in prediction of VETC. ⢠Peritumoral radiomics-model-predicted VETC was an independent predictor of early recurrence and progression-free survival.
Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Carcinoma, Hepatocellular/diagnostic imaging , Contrast Media , Gadolinium DTPA , Humans , Liver Neoplasms/diagnostic imaging , Magnetic Resonance Imaging , Prognosis , Retrospective StudiesABSTRACT
OBJECTIVE: To identify superior pain-control procedures for postoperative patients who undergo cardiac surgeries. METHODS: Literature searches were conducted in globally recognized databases, including MEDLINE, EMBASE and Cochrane Central, to identify randomized controlled trials (RCTs) investigating pain-control procedures after cardiac surgeries. The parameters evaluating analgesic efficacy and postoperative recovery, namely, the pain score and ICU stay, were quantitatively pooled and estimated using Bayesian methods. The values of the surface under the cumulative ranking (SUCRA) probabilities regarding each parameter were calculated to enable the ranking of various pain-control procedures. Node-splitting analysis was performed to test the inconsistency of the main results, and the publication bias was assessed by examining the funnel-plot symmetry. RESULTS: After a detailed review, 13 RCTs containing 7 different procedures were included in the network meta-analysis. After pooling the results together, an erector spinae plane block (ESPB) and a local parasternal block (LPB) plus target-controlled infusion (TCI) presented the best analgesic effects for reducing pain at rest (SUCRA, .47) and during movement (SUCRA, .52), respectively, while the former also achieved the shortest ICU stay (SUCRA, .48). Moreover, the funnel-plot symmetries showed no inconsistencies or obvious publication bias in the current study. CONCLUSIONS: The current evidence indicates that ESPB is a potential superior analgesic strategy for post-cardiac surgery patients. To verify this conclusion further, it is imperative to obtain more high-quality evidence and conduct relevant investigations in the future.
Subject(s)
Cardiac Surgical Procedures , Bayes Theorem , Cardiac Surgical Procedures/adverse effects , Humans , Network Meta-Analysis , Pain , Pain, Postoperative/drug therapyABSTRACT
BACKGROUND: Nuclear protein Ki-67 indicates the status of cell proliferation and has been regarded as an attractive biomarker for the prognosis of HCC. The aim of this study is to investigate which radiomics model derived from different sequences and phases of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MRI was superior to predict Ki-67 expression in hepatocellular carcinoma (HCC), then further to validate the optimal model for preoperative prediction of Ki-67 expression in HCC. METHODS: This retrospective study included 151 (training cohort: n = 103; validation cohort: n = 48) pathologically confirmed HCC patients. Radiomics features were extracted from the artery phase (AP), portal venous phase (PVP), hepatobiliary phase (HBP), and T2-weighted (T2W) images. A logistic regression with the least absolute shrinkage and selection operator (LASSO) regularization was used to select features to build a radiomics score (Rad-score). A final combined model including the optimal Rad-score and clinical risk factors was established. Receiver operating characteristic (ROC) curve analysis, Delong test and calibration curve were used to assess the predictive performance of the combined model. Decision cure analysis (DCA) was used to evaluate the clinical utility. RESULTS: The AP radiomics model with higher decision curve indicating added more net benefit, gave a better predictive performance than the HBP and T2W radiomic models. The combined model (AUC = 0.922 vs. 0.863) including AP Rad-score and serum AFP levels improved the predictive performance more than the AP radiomics model (AUC = 0.873 vs. 0.813) in the training and validation cohort. Calibration curve of the combined model showed a good agreement between the predicted and the actual probability. DCA of the validation cohort revealed that at a range threshold probability of 30-60%, the combined model added more net benefit compared with the AP radiomics model. CONCLUSIONS: A combined model including AP Rad-score and serum AFP levels based on enhanced MRI can preoperatively predict Ki-67 expression in HCC.
Subject(s)
Carcinoma, Hepatocellular/diagnostic imaging , Contrast Media , Gadolinium DTPA , Ki-67 Antigen/metabolism , Liver Neoplasms/diagnostic imaging , Magnetic Resonance Imaging/methods , Carcinoma, Hepatocellular/blood , Carcinoma, Hepatocellular/blood supply , Carcinoma, Hepatocellular/metabolism , Cohort Studies , Female , Humans , Liver Neoplasms/blood , Liver Neoplasms/blood supply , Liver Neoplasms/metabolism , Logistic Models , Male , Middle Aged , ROC Curve , Retrospective Studies , alpha-Fetoproteins/analysisABSTRACT
In this paper, a new method to calibrate a trinocular vision sensor is presented. A planar target with several parallel lines is utilized. The trifocal tensor of three image planes can be calculated out according to line correspondences. Compatible essential matrix between each two cameras can be obtained. Then, rotation matrix and translation matrix can be deduced base on singular value decomposition of their corresponding essential matrix. In our proposed calibration method, image rectification is carried out to remove perspective distortion. As the feature utilized is straight line, precise point to point correspondence is not necessary. Experimental results show that our proposed calibration method can obtain precise results. Moreover, the trifocal tensor can also give a strict constraint for feature matching as descripted in our previous work. Root mean square error of measured distances is 0.029 mm with regards to the view field of about 250×250 mm. As parallel feature exists widely in natural scene, our calibration method also provides a new approach for self-calibration of a trinocular vision sensor.
ABSTRACT
BACKGROUND: To develop and validate a nomogram for early identification of severe coronavirus disease 2019 (COVID-19) based on initial clinical and CT characteristics. METHODS: The initial clinical and CT imaging data of 217 patients with COVID-19 were analyzed retrospectively from January to March 2020. Two hundred seventeen patients with 146 mild cases and 71 severe cases were randomly divided into training and validation cohorts. Independent risk factors were selected to construct the nomogram for predicting severe COVID-19. Nomogram performance in terms of discrimination and calibration ability was evaluated using the area under the curve (AUC), calibration curve, decision curve, clinical impact curve and risk chart. RESULTS: In the training cohort, the severity score of lung in the severe group (7, interquartile range [IQR]:5-9) was significantly higher than that of the mild group (4, IQR,2-5) (P < 0.001). Age, density, mosaic perfusion sign and severity score of lung were independent risk factors for severe COVID-19. The nomogram had a AUC of 0.929 (95% CI, 0.889-0.969), sensitivity of 84.0% and specificity of 86.3%, in the training cohort, and a AUC of 0.936 (95% CI, 0.867-1.000), sensitivity of 90.5% and specificity of 88.6% in the validation cohort. The calibration curve, decision curve, clinical impact curve and risk chart showed that nomogram had high accuracy and superior net benefit in predicting severe COVID-19. CONCLUSION: The nomogram incorporating initial clinical and CT characteristics may help to identify the severe patients with COVID-19 in the early stage.
Subject(s)
Coronavirus Infections/diagnostic imaging , Lung/diagnostic imaging , Nomograms , Pneumonia, Viral/diagnostic imaging , Adolescent , Adult , Aged , Aged, 80 and over , Area Under Curve , COVID-19 , Child , Early Diagnosis , Humans , Middle Aged , Pandemics , Random Allocation , Retrospective Studies , Sensitivity and Specificity , Severity of Illness Index , Tomography, X-Ray Computed , Young AdultABSTRACT
Aromatic [5,5]-sigmatropic rearrangement is an appealing protocol for accessing 1,4-substituted arenes. However, such a protocol has not been well utilized in organic synthesis because of the difficulties in the synthesis of the substrates, selectivity issues, and limited substrate scope. Described herein is a new [5,5]-sigmatropic reaction utilizing readily available aryl sulfoxides and allyl nitriles. This reaction features mild reaction conditions, high chemo- and regioselectivity, excellent functional-group compatibility, and broad substrate scope. Computational studies suggest that the success of the reaction can be attributed to the selective electrophilic assembly of the rearrangement precursors, in which a linear -C=C=N- linkage favors [5,5]-sigmatropic rearrangement over the competitive [3,3]-sigmatropic rearrangement.
ABSTRACT
Respiratory syncytial virus (RSV) is a major cause of respiratory infections in infants and the elderly, leading to more deaths than influenza each year, but there is no antiviral or efficacious vaccine currently available. Here we examine the role in infection of the host mitochondrial protein p32 (HABP/gC1qR/C1qbp) for the first time. RSV replication as well as infectious virus production was significantly reduced by p32 siRNA knockdown, consistent with an important role for p32 in RSV infection. p32 showed distinct mitochondrial localization throughout RSV infection, but immunostaining and high resolution confocal imaging for p32 as well as MitoTracker Red and cytochrome c, revealed clear changes in mitochondrial organization in RSV infection, with perinuclear mitochondrial compaction and asymmetric distribution at 8 and 18 h post-infection, respectively. The results implicate p32 as a key host factor for RSV virus production, and bring to light the potential importance of mitochondria in RSV infection.
Subject(s)
Carrier Proteins/metabolism , Mitochondrial Proteins/metabolism , Respiratory Syncytial Viruses/growth & development , Respiratory Syncytial Viruses/metabolism , A549 Cells , Carrier Proteins/genetics , Humans , Mitochondrial Proteins/genetics , RNA, Small Interfering/genetics , Tumor Cells, CulturedABSTRACT
Coumarins are plant-derived natural products with a broad range of known pharmacological activities including anticancer effects. However, the molecular mechanisms by which this class of promising compounds exerts their anticancer effects remain largely unknown. We report here that a furanocoumarin named apaensin could effectively induce apoptosis of cancer cells through its activation of Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK). Apoptosis induction by apaensin in cancer cells was suppressed by chemical inhibitors of JNK and p38 MAPK. Inhibition of the expression of orphan nuclear receptor Nur77 by small interfering RNA (siRNA) approach also abrogated the death effect of apaensin. Molecular analysis demonstrated that JNK activation was required for the nuclear export of Nur77, a known apoptotic event in cancer cells. Although p38 MAPK activation was not involved in Nur77 nuclear export, it was essential for Nur77 mitochondrial targeting through induction of Nur77 interaction with Bcl-2, which is also known to convert Bcl-2 from an antiapoptotic to a proapoptotic molecule. Together, our results identify a new natural product that targets orphan nuclear receptor Nur77 through its unique activation of JNK and p38 MAPK and provide insight into the complex regulation of the Nur77-Bcl-2 apoptotic pathway.
Subject(s)
Apoptosis/drug effects , Breast Neoplasms/pathology , Furocoumarins/pharmacology , JNK Mitogen-Activated Protein Kinases/metabolism , Lung Neoplasms/pathology , Nuclear Receptor Subfamily 4, Group A, Member 1/metabolism , p38 Mitogen-Activated Protein Kinases/metabolism , Angelica/chemistry , Blotting, Western , Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Cell Proliferation/drug effects , Female , Humans , Immunoprecipitation , Lung Neoplasms/drug therapy , Lung Neoplasms/metabolism , Microscopy, Fluorescence , Phosphorylation , Proto-Oncogene Proteins c-bcl-2/metabolism , Signal Transduction/drug effects , Tumor Cells, CulturedABSTRACT
p32 [also known as HABP1 (hyaluronan-binding protein 1), gC1qR (receptor for globular head domains complement 1q) or C1qbp (complement 1q-binding protein)] has been shown previously to have both mitochondrial and non-mitochondrial localization and functions. In the present study, we show for the first time that endogenous p32 protein is a mitochondrial protein in HeLa cells under control and stress conditions. In defining the impact of altering p32 levels in these cells, we demonstrate that the overexpression of p32 increased mitochondrial fibrils. Conversely, siRNA-mediated p32 knockdown enhanced mitochondrial fragmentation accompanied by a loss of detectable levels of the mitochondrial fusion mediator proteins Mfn (mitofusin) 1 and Mfn2. More detailed ultrastructure analysis by transmission electron microscopy revealed aberrant mitochondrial structures with less and/or fragmented cristae and reduced mitochondrial matrix density as well as more punctate ER (endoplasmic reticulum) with noticeable dissociation of their ribosomes. The analysis of mitochondrial bioenergetics showed significantly reduced capacities in basal respiration and oxidative ATP turnover following p32 depletion. Furthermore, siRNA-mediated p32 knockdown resulted in differential stress-dependent effects on cell death, with enhanced cell death observed in the presence of hyperosmotic stress or cisplatin treatment, but decreased cell death in the presence of arsenite. Taken together, our studies highlight the critical contributions of the p32 protein to the morphology of mitochondria and ER under normal cellular conditions, as well as important roles of the p32 protein in cellular metabolism and various stress responses.
Subject(s)
Carrier Proteins/metabolism , Endoplasmic Reticulum/metabolism , Mitochondria/metabolism , Mitochondrial Proteins/metabolism , Adenosine Triphosphate/metabolism , Carrier Proteins/genetics , Endoplasmic Reticulum/ultrastructure , HeLa Cells , Humans , Immunoblotting , Microscopy, Confocal , Mitochondria/ultrastructure , Mitochondrial Proteins/geneticsABSTRACT
Objectives: The primary aim of this study is to discern the association between specific clinical parameters and low muscle mass (LMM). We endeavor to elucidate the determinants of LMM and the predictive potency of individual factors. Methods: In this retrospective cross-sectional study, we encompassed 450 older adult Chinese participants (252 males and 198 females). Muscle mass quantifications were performed using bioelectrical impedance analysis. Comprehensive data encompassing demographic details (age, sex, height, and weight) and laboratory results (complete blood count, thyroid function, liver function, and renal function) were systematically recorded. Logistic regression models, coupled with receiver operating characteristic curve analytics, were employed to ascertain the variables influencing LMM and to evaluate the predictive validity of each parameter on LMM. Results: Upon confounding adjustment for age, gender, body mass index (BMI), and free thyroxine (FT4) persisted as a determinant of LMM. Specifically, individuals with an FT4 exceeding 1.105 ng/dL exhibited a 1.803-fold increased propensity for LMM relative to those with FT4 values below the specified threshold. Incorporating age, gender, BMI, and FT4 in the diagnostic algorithm enhanced the precision of LMM. The results differ between men and women. In the male population, we can still observe that FT4 has a certain value in the diagnosis of LMM, but this phenomenon is not found in the female population. Conclusions: Elevated FT4 concentrations, albeit within clinically accepted limits, are inversely associated with muscle mass. As such, FT4 could be postulated as a potential biomarker for LMM in geriatric individuals, especially in the male group.
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von Hippel-Lindau (VHL), known as a tumor suppressor gene, is frequently mutated in clear cell renal cell carcinoma (ccRCC). However, VHL mutation is not sufficient to promote tumor formation. In most cases other than ccRCC, VHL loss alters cellular homeostasis and causes cell stress and metabolic changes by stabilizing hypoxia-inducible factor (HIF) levels, resulting in a fitness disadvantage. In addition, the function of VHL in regulating immune response is still not well established. In this study, we demonstrate that VHL loss enhances the efficacy of anti-programmed death 1 (PD1) treatment in multiple murine tumor models in a T cell-dependent manner. Mechanistically, we discovered that upregulation of HIF1α/2α induced by VHL loss decreased mitochondrial outer membrane potential and caused the cytoplasmic leakage of mitochondrial DNA, which triggered cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) activation and induced type I interferons. Our study thus provided mechanistic insights into the role of VHL gene loss in boosting antitumor immunity.
ABSTRACT
Radiotherapy (RT) is commonly used to try to eliminate any remaining tumor cells following surgical resection of glioma. However, tumor recurrence is prevalent, highlighting the unmet medical need to develop therapeutic strategies to enhance the efficacy of RT in glioma. Focusing on the radiosensitizing potential of currently approved drugs known to cross the blood-brain barrier can facilitate rapid clinical translation. Here, we assessed the role of catechol-o-methyltransferase (COMT), a key enzyme to degrade catecholamines and a drug target for Parkinson's disease, in glioma treatment. Analysis of TCGA data showed significantly higher COMT expression levels in both low-grade glioma and glioblastoma compared to normal brain tissues. Inhibition of COMT by genetic knockout or FDA-approved COMT inhibitors significantly sensitized glioma cells to RT in vitro and in vivo. Mechanistically, COMT inhibition in glioma cells led to mitochondria dysfunction and increased mitochondrial RNA release into the cytoplasm, activating the cellular antiviral double-stranded RNA sensing pathway and type I interferon (IFN) response. Elevated type I IFNs stimulated the phagocytic capacity of microglial cells, enhancing RT efficacy. Given the long-established safety record of the COMT inhibitors, these findings provide a solid rationale to evaluate them in combination with RT in glioma patients.
ABSTRACT
INTRODUCTION: Treatment of spine fractures may require periods of prolonged immobilization which prevents effective pulmonary toileting. We hypothesized that patients with longer time to mobilization, as measured by time to first physical therapy (PT) session, would have higher pulmonary complications. METHODS: We performed a retrospective review of all trauma patients with cervical and thoracolumbar spinal fractures admitted to a level 1 trauma center over a 12-month period. Demographic data collection included age, gender, BMI, pulmonary comorbidities, concomitant rib fractures, admission GCS, Injury Severity Score (ISS), GCS at 24 h, treatment with cervical or thoracolumbar immobilization, and time to first PT evaluation. The primary outcome was the presence of any one of the following complications: unplanned intubation, pneumonia, or mortality at 30 days. Multivariable logistic regression analysis was used to assess significant predictors of pulmonary complication. RESULTS: In total, 491 patients were identified. In terms of overall pulmonary complications, 10% developed pneumonia, 13% had unplanned intubation, and 6% died within 30 days. In total, 19% developed one or more complication. Overall, 25% of patients were seen by PT <48 h, 33% between 48 and 96 h, 19% at 96 h to 1 week, and 7% > 1 week. Multivariable logistic regression analysis showed that time to PT session (OR 1.010, 95% CI 1.005-1.016) and ISS (OR 1.063, 95% CI 1.026-1.102) were independently associated with pulmonary complication. CONCLUSION: Time to mobility is independently associated with pulmonary complications in patients with spine fractures.