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Cells May 2024Intracellular cargo delivery via distinct transport routes relies on vesicle carriers. A key trafficking route distributes cargo taken up by clathrin-mediated...
Intracellular cargo delivery via distinct transport routes relies on vesicle carriers. A key trafficking route distributes cargo taken up by clathrin-mediated endocytosis (CME) via early endosomes. The highly dynamic nature of the endosome network presents a challenge for its quantitative analysis, and theoretical modelling approaches can assist in elucidating the organization of the endosome trafficking system. Here, we introduce a new computational modelling approach for assessment of endosome distributions. We employed a model of induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) with inherited mutations causing dilated cardiomyopathy (DCM). In this model, vesicle distribution is defective due to impaired CME-dependent signaling, resulting in plasma membrane-localized early endosomes. We recapitulated this in iPSC-CMs carrying two different mutations, TPM1-L185F and TnT-R141W (MUT), using 3D confocal imaging as well as super-resolution STED microscopy. We computed scaled distance distributions of EEA1-positive vesicles based on a spherical approximation of the cell. Employing this approach, 3D spherical modelling identified a bi-modal segregation of early endosome populations in MUT iPSC-CMs, compared to WT controls. Moreover, spherical modelling confirmed reversion of the bi-modal vesicle localization in RhoA II-treated MUT iPSC-CMs. This reflects restored, homogeneous distribution of early endosomes within MUT iPSC-CMs following rescue of CME-dependent signaling via RhoA II-dependent RhoA activation. Overall, our approach enables assessment of early endosome distribution in cell-based disease models. This new method may provide further insight into the dynamics of endosome networks in different physiological scenarios.
Topics: Humans; Induced Pluripotent Stem Cells; Endosomes; Myocytes, Cardiac; Endocytosis; Mutation; Computer Simulation; rhoA GTP-Binding Protein; Cardiomyopathies; Imaging, Three-Dimensional; Cardiomyopathy, Dilated; Models, Biological; Tropomyosin
PubMed: 38891055
DOI: 10.3390/cells13110923 -
Cells May 2024Plasma gelsolin (pGSN) overexpression in ovarian cancer (OVCA) disarms immune function, contributing to chemoresistance. The aim of this study was to investigate the...
Plasma gelsolin (pGSN) overexpression in ovarian cancer (OVCA) disarms immune function, contributing to chemoresistance. The aim of this study was to investigate the immunoregulatory effects of pGSN expression on natural killer (NK) cell function in OVCA. OVCA tissues from primary surgeries underwent immunofluorescent staining of pGSN and the activated NK cell marker natural cytotoxicity triggering receptor 1 to analyze the prognostic impact of pGSN expression and activated NK cell infiltration. The immunoregulatory effects of pGSN on NK cells were assessed using apoptosis assay, cytokine secretion, immune checkpoint-receptor expression, and phosphorylation of STAT3. In OVCA tissue analyses, activated NK cell infiltration provided survival advantages to patients. However, high pGSN expression attenuated the survival benefits of activated NK cell infiltration. In the in vitro experiment, pGSN in OVCA cells induced NK cell death through cell-to-cell contact. pGSN increased T-cell immunoglobulin and mucin-domain-containing-3 expression (TIM-3) on activated NK cells. Further, it decreased interferon-γ production in activated TIM-3+ NK cells, attenuating their anti-tumor effects. Thus, increased pGSN expression suppresses the anti-tumor functions of NK cells. The study provides insights into why immunotherapy is rarely effective in patients with OVCA and suggests novel treatment strategies.
Topics: Humans; Killer Cells, Natural; Female; Gelsolin; Carcinoma, Ovarian Epithelial; Drug Resistance, Neoplasm; Ovarian Neoplasms; Cell Line, Tumor; Middle Aged; Hepatitis A Virus Cellular Receptor 2; Apoptosis; STAT3 Transcription Factor; Interferon-gamma
PubMed: 38891037
DOI: 10.3390/cells13110905 -
PeerJ 2024Keloid is a chronic proliferative fibrotic disease caused by abnormal fibroblasts proliferation and excessive extracellular matrix (ECM) production. Numerous fibrotic...
BACKGROUND
Keloid is a chronic proliferative fibrotic disease caused by abnormal fibroblasts proliferation and excessive extracellular matrix (ECM) production. Numerous fibrotic disorders are significantly influenced by ferroptosis, and targeting ferroptosis can effectively mitigate fibrosis development. This study aimed to investigate the role and mechanism of ferroptosis in keloid development.
METHODS
Keloid tissues from keloid patients and normal skin tissues from healthy controls were collected. Iron content, lipid peroxidation (LPO) level, and the mRNA and protein expression of ferroptosis-related genes including solute carrier family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GPX4), transferrin receptor (TFRC), and nuclear factor erythroid 2-related factor 2 (Nrf2) were determined. Mitochondrial morphology was observed using transmission electron microscopy (TEM). Keloid fibroblasts (KFs) were isolated from keloid tissues, and treated with ferroptosis inhibitor ferrostatin-1 (fer-1) or ferroptosis activator erastin. Iron content, ferroptosis-related marker levels, LPO level, mitochondrial membrane potential, ATP content, and mitochondrial morphology in KFs were detected. Furthermore, the protein levels of α-smooth muscle actin (α-SMA), collagen I, and collagen III were measured to investigate whether ferroptosis affect fibrosis in KFs.
RESULTS
We found that iron content and LPO level were substantially elevated in keloid tissues and KFs. SLC7A11, GPX4, and Nrf2 were downregulated and TFRC was upregulated in keloid tissues and KFs. Mitochondria in keloid tissues and KFs exhibited ferroptosis-related pathology. Fer-1 treatment reduced iron content, restrained ferroptosis and mitochondrial dysfunction in KFs, Moreover, ferrostatin-1 restrained the protein expression of α-SMA, collagen I, and collagen III in KFs. Whereas erastin treatment showed the opposite results.
CONCLUSION
Ferroptosis exists in keloid. Ferrostatin-1 restrained ECM deposition and fibrosis in keloid through inhibiting ferroptosis, and erastin induced ECM deposition and fibrosis through intensifying ferroptosis.
Topics: Humans; Ferroptosis; Keloid; Fibroblasts; Cyclohexylamines; Fibrosis; Phenylenediamines; NF-E2-Related Factor 2; Phospholipid Hydroperoxide Glutathione Peroxidase; Male; Lipid Peroxidation; Female; Adult; Iron; Amino Acid Transport System y+; Receptors, Transferrin; Piperazines; Actins; Mitochondria; Membrane Potential, Mitochondrial
PubMed: 38887622
DOI: 10.7717/peerj.17551 -
Head and Neck Pathology Jun 2024The aim of the study is to investigate the immunohistochemical expression of both Alpha smooth muscle actin and Transforming Growth Factor beta and compare their... (Comparative Study)
Comparative Study
PURPOSE
The aim of the study is to investigate the immunohistochemical expression of both Alpha smooth muscle actin and Transforming Growth Factor beta and compare their expression in oral papillary squamous cell carcinoma with their expression in different histological grades of oral squamous cell carcinoma. A correlation between these immuno-histochemical expressions and histological findings will then be performed. The research question is "Do the percentages of α-SMA and TGF-β immune-expression in OPSCC differ from that in the conventional OSCC?".
METHODS
This will be achieved by collecting archival blocks of oral papillary squamous cell carcinoma and different grades of oral squamous cell carcinoma, staining the specimens with Transforming Growth Factor beta and alpha smooth muscle actin, then measuring the mean staining index of expression in each group and the area percent of both markers.
RESULTS
Results revealed that transforming growth factor beta expression in the epithelium was high in all cases of well-differentiated squamous cell carcinoma, most oral papillary squamous cell carcinoma, and poorly differentiated oral squamous cell carcinoma. On the other hand, different grades of oral squamous cell carcinoma showed a high staining index of alpha smooth muscle actin expression in the stroma. While cases of oral papillary squamous cell carcinoma were either moderate or low-staining.
CONCLUSIONS
Oral papillary squamous cell carcinoma has a favourable prognosis compared to different histological grades, and the prognosis does not depend only on histological grade but also on other prognostic factors.
Topics: Humans; Mouth Neoplasms; Immunohistochemistry; Actins; Biomarkers, Tumor; Carcinoma, Squamous Cell; Squamous Cell Carcinoma of Head and Neck; Transforming Growth Factor beta; Male; Female
PubMed: 38884825
DOI: 10.1007/s12105-024-01635-4 -
Investigative Ophthalmology & Visual... Jun 2024We investigated the natural history of retinal dystrophy owing to variants in the MYO7A gene.
PURPOSE
We investigated the natural history of retinal dystrophy owing to variants in the MYO7A gene.
METHODS
Fifty-three patients (mean age, 33.6 ± 16.7 years) with Usher syndrome owing to biallelic, mostly pathogenic, variants in MYO7A underwent baseline and two annual follow-up visits. Best-corrected visual acuity (BCVA), semiautomatic kinetic visual field, full-field electroretinogram, color fundus imaging, microperimetry, spectral-domain optical coherence tomography, and fundus autofluorescence were assessed.
RESULTS
At baseline, all patients presented with decreased BCVA (66.4 ± 17.9 Early Treatment Diabetic Retinopathy score and 59.5 ± 21.7 Early Treatment Diabetic Retinopathy score, in the better- and worse-seeing eyes, respectively), restricted semiautomatic kinetic visual field (III4e area, 3365.8 ± 4142.1°2; 4176.4 ± 4400.3°2) and decreased macular sensitivity (9.7 ± 9.9 dB; 9.0 ± 10.2 dB). Spectral-domain optical coherence tomography revealed reduced central macular thickness (259.6 ± 63.0 µm; 250.7 ± 63.3 µm) and narrowed ellipsoid zone band width (2807.5 ± 2374.6 µm; 2615.5 ± 2370.4 µm). Longitudinal analyses (50 patients) showed a significant decrease of BCVA in better-seeing eyes, whereas no changes were observed in worse-seeing eyes for any parameter. BCVA, semiautomatic kinetic visual field (III4e and V4e) and macular sensitivity were related significantly to age at baseline. Hyperautofluorescent foveal patch (16 eyes [31.4%]) and abnormal central hypoautofluorescence (9 eyes [17.6%]) were significantly associated with worse morphological and functional read-outs compared with the hyperautofluorescent ring pattern (22 eyes [43.1%]).
CONCLUSIONS
Our European multicentric study offers the first prospective longitudinal analysis in one of the largest cohorts of MYO7A patients described to date, confirming the slow disease progression. More important, this study emphasizes the key role of fundus autofluorescence patterns in retinal impairment staging and advocates its adoption as an objective biomarker in patient selection for future gene therapy clinical trials.
Topics: Humans; Male; Female; Adult; Prospective Studies; Tomography, Optical Coherence; Visual Acuity; Middle Aged; Electroretinography; Myosin VIIa; Visual Fields; Young Adult; Adolescent; Usher Syndromes; Genetic Therapy; Child; Visual Field Tests; Europe; Fluorescein Angiography; Follow-Up Studies; Aged; Longitudinal Studies; Disease Progression; Myosins; Retina
PubMed: 38884554
DOI: 10.1167/iovs.65.6.25 -
Journal of Experimental & Clinical... Jun 2024Cancer is characterized by dysregulated cellular metabolism. Thus, understanding the mechanisms underlying these metabolic alterations is important for developing...
BACKGROUND
Cancer is characterized by dysregulated cellular metabolism. Thus, understanding the mechanisms underlying these metabolic alterations is important for developing targeted therapies. In this study, we investigated the pro-tumoral effect of PDZ and LIM domain 2 (PDLIM2) downregulation in lung cancer growth and its association with the accumulation of mitochondrial ROS, oncometabolites and the activation of hypoxia-inducible factor-1 (HIF-1) α in the process.
METHODS
Databases and human cancer tissue samples were analyzed to investigate the roles of PDLIM2 and HIF-1α in cancer growth. DNA microarray and gene ontology enrichment analyses were performed to determine the cellular functions of PDLIM2. Seahorse assay, flow cytometric analysis, and confocal microscopic analysis were employed to study mitochondrial functions. Oncometabolites were analyzed using liquid chromatography-mass spectrometry (LC-MS). A Lewis lung carcinoma (LLC) mouse model was established to assess the in vivo function of PDLIM2 and HIF-1α.
RESULTS
The expression of PDLIM2 was downregulated in lung cancer, and this downregulation correlated with poor prognosis in patients. PDLIM2 highly regulated genes associated with mitochondrial functions. Mechanistically, PDLIM2 downregulation resulted in NF-κB activation, impaired expression of tricarboxylic acid (TCA) cycle genes particularly the succinate dehydrogenase (SDH) genes, and mitochondrial dysfunction. This disturbance contributed to the accumulation of succinate and other oncometabolites, as well as the buildup of mitochondrial reactive oxygen species (mtROS), leading to the activation of hypoxia-inducible factor 1α (HIF-1α). Furthermore, the expression of HIF-1α was increased in all stages of lung cancer. The expression of PDLIM2 and HIF-1α was reversely correlated in lung cancer patients. In the animal study, the orally administered HIF-1α inhibitor, PX-478, significantly reduces PDLIM2 knockdown-promoted tumor growth.
CONCLUSION
These findings shed light on the complex action of PDLIM2 on mitochondria and HIF-1α activities in lung cancer, emphasizing the role of HIF-1α in the tumor-promoting effect of PDLIM2 downregulation. Additionally, they provide new insights into a strategy for precise targeted treatment by suggesting that HIF-1α inhibitors may serve as therapy for lung cancer patients with PDLIM2 downregulation.
Topics: Humans; LIM Domain Proteins; Animals; Hypoxia-Inducible Factor 1, alpha Subunit; Mice; Mitochondria; Reactive Oxygen Species; Down-Regulation; Lung Neoplasms; Cell Line, Tumor; Microfilament Proteins; Carcinoma, Lewis Lung; Gene Expression Regulation, Neoplastic; Female; Male
PubMed: 38880883
DOI: 10.1186/s13046-024-03094-9 -
Journal of Cancer Research and Clinical... Jun 2024Metastasis is a main cause of death from ovarian cancer (OC). Identifying key markers involved in OC metastasis can aid in the effective detection of early postoperative...
BACKGROUND
Metastasis is a main cause of death from ovarian cancer (OC). Identifying key markers involved in OC metastasis can aid in the effective detection of early postoperative metastasis. However, the role of FCGR1A in OC metastasis has yet to be fully established. A genome-wide CRISPR/Cas9-based screening system was used to identify regulatory factors involved in metastasis.
METHODS
The expression of FCGR1A and LSP1 in ovarian cancer cell lines was examined by quantitative real-time polymerase chain reaction (qRT‒PCR). The functions of FCGR1A and LSP1 in OC cell migration, invasion and proliferation were determined using wound healing, Transwell invasion and CKK-8 assays. A transcription-activated library was used to identify the potential downstream genes of FCGR1A. FCGR1A expression was detected by immunohistochemistry and the immunity risk score (IRS) scores were calculated.
RESULTS
FCGR1A was upregulated in OC cells compared with normal ovarian cells. Downregulation of FCGR1A inhibited metastasis, proliferation and epithelial-mesenchymal transition (EMT) progression in OC cells in vitro and intraperitoneal metastasis in vivo. Moreover, downregulation of FCGR1A was accompanied by decreased LSP1 expression. Overexpression of LSP1 partially reversed the tumor suppressive effect of FCGR1A downregulation. Higher FCGR1A expression was related to metastasis, higher grade, higher stage, and lymph node metastasis in OC. Survival analysis suggested that the group with higher FCGR1A expression had a lower tumor-free survival rate and a lower overall survival rate than did the group with low FCGR1A expression.
CONCLUSIONS
FCGR1A enhances OC metastasis by regulating LSP1, and FCGR1A is associated with poor prognosis, suggesting that FCGR1A is a potential predictive factor for detecting early postoperative metastasis.
Topics: Female; Humans; Ovarian Neoplasms; CRISPR-Cas Systems; Mice; Animals; Cell Line, Tumor; Receptors, IgG; Cell Proliferation; Neoplasm Metastasis; Mice, Nude; Cell Movement; Epithelial-Mesenchymal Transition; Gene Expression Regulation, Neoplastic; Cell Adhesion Molecules; Mice, Inbred BALB C; Microfilament Proteins
PubMed: 38879666
DOI: 10.1007/s00432-024-05837-9 -
Journal of the American Heart... Jun 2024Cardiac troponin is extensively used as a biomarker in modern medicine due to its diagnostic capability for myocardial injury, as well as its predictive and prognostic... (Review)
Review
Cardiac troponin is extensively used as a biomarker in modern medicine due to its diagnostic capability for myocardial injury, as well as its predictive and prognostic value for cardiac diseases. However, heterophile antibodies, antitroponin antibodies, and macrotroponin complexes can be observed both in seemingly healthy individuals and patients with cardiac diseases, potentially leading to false positive or disproportionate elevation of cTn (cardiac troponin) assay results and introducing discrepancies in clinical interpretations with impact on medical management. In this review article, we describe the possible mechanisms of cTn release and the sources of variations in the assessment of circulating cTn levels. We also explore the pathophysiological mechanisms underlying antitroponin antibody development and discuss the influence exerted by macrotroponin complexes on the results of immunoassays. Additionally, we explore approaches to detect these complexes by presenting various clinical scenarios encountered in routine clinical practice. Finally, unsolved questions about the development, prevalence, and clinical significance of cardiac autoantibodies are discussed.
Topics: Humans; Biomarkers; Autoantibodies; Heart Diseases; Predictive Value of Tests; Troponin I; Prognosis
PubMed: 38879450
DOI: 10.1161/JAHA.123.035128 -
Proceedings of the National Academy of... Jun 2024Plants rely on immune receptor complexes at the cell surface to perceive microbial molecules and transduce these signals into the cell to regulate immunity. Various...
Plants rely on immune receptor complexes at the cell surface to perceive microbial molecules and transduce these signals into the cell to regulate immunity. Various immune receptors and associated proteins are often dynamically distributed in specific nanodomains on the plasma membrane (PM). However, the exact molecular mechanism and functional relevance of this nanodomain targeting in plant immunity regulation remain largely unknown. By utilizing high spatiotemporal resolution imaging and single-particle tracking analysis, we show that myosin XIK interacts with remorin to recruit and stabilize PM-associated kinase BOTRYTIS-INDUCED KINASE 1 (BIK1) within immune receptor FLAGELLIN SENSING 2 (FLS2)-containing nanodomains. This recruitment facilitates FLS2/BIK1 complex formation, leading to the full activation of BIK1-dependent defense responses upon ligand perception. Collectively, our findings provide compelling evidence that myosin XI functions as a molecular scaffold to enable a spatially confined complex assembly within nanodomains. This ensures the presence of a sufficient quantity of preformed immune receptor complex for efficient signaling transduction from the cell surface.
Topics: Arabidopsis; Arabidopsis Proteins; Cell Membrane; Immunity, Innate; Myosins; Plant Diseases; Plant Immunity; Protein Kinases; Protein Serine-Threonine Kinases; Signal Transduction
PubMed: 38875149
DOI: 10.1073/pnas.2312415121 -
Molecular Biomedicine Jun 2024Sleep deprivation (SD) has emerged as a critical concern impacting human health, leading to significant damage to the cardiovascular system. However, the underlying...
Sleep deprivation (SD) has emerged as a critical concern impacting human health, leading to significant damage to the cardiovascular system. However, the underlying mechanisms are still unclear, and the development of targeted drugs is lagging. Here, we used mice to explore the effects of prolonged SD on cardiac structure and function. Echocardiography analysis revealed that cardiac function was significantly decreased in mice after five weeks of SD. Real-time quantitative PCR (RT-q-PCR) and Masson staining analysis showed that cardiac remodeling marker gene Anp (atrial natriuretic peptide) and fibrosis were increased, Elisa assay of serum showed that the levels of creatine kinase (CK), creatine kinase-MB (CK-MB), ANP, brain natriuretic peptide (BNP) and cardiac troponin T (cTn-T) were increased after SD, suggesting that cardiac remodeling and injury occurred. Transcript sequencing analysis indicated that genes involved in the regulation of calcium signaling pathway, dilated cardiomyopathy, and cardiac muscle contraction were changed after SD. Accordingly, Western blotting analysis demonstrated that the cardiac-contraction associated CaMKK2/AMPK/cTNI pathway was inhibited. Since our preliminary research has confirmed the vital role of Casein Kinase-2 -Interacting Protein-1 (CKIP-1, also known as PLEKHO1) in cardiac remodeling regulation. Here, we found the levels of the 3' untranslated region of Ckip-1 (Ckip-1 3'UTR) decreased, while the coding sequence of Ckip-1 (Ckip-1 CDS) remained unchanged after SD. Significantly, adenovirus-mediated overexpression of Ckip-1 3'UTR alleviated SD-induced cardiac dysfunction and remodeling by activating CaMKK2/AMPK/cTNI pathway, which proposed the therapeutic potential of Ckip-1 3'UTR in treating SD-induced heart disease.
Topics: Animals; Male; Mice; 3' Untranslated Regions; AMP-Activated Protein Kinases; Calcium-Calmodulin-Dependent Protein Kinase Kinase; Carrier Proteins; Mice, Inbred C57BL; Myocardium; Signal Transduction; Sleep Deprivation; Troponin I
PubMed: 38871861
DOI: 10.1186/s43556-024-00186-y