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1.
Front Immunol ; 15: 1369780, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38868771

RESUMO

Although most follicular-derived thyroid cancers are well differentiated and have an overall excellent prognosis following treatment with surgery and radioiodine, management of advanced thyroid cancers, including iodine refractory disease and poorly differentiated/undifferentiated subtypes, is more challenging. Over the past decade, better understanding of the genetic drivers and immune milieu of advanced thyroid cancers has led to significant progress in the management of these patients. Numerous targeted kinase inhibitors are now approved by the U.S Food and Drug administration (FDA) for the treatment of advanced, radioiodine refractory differentiated thyroid cancers (DTC) as well as anaplastic thyroid cancer (ATC). Immunotherapy has also been thoroughly studied and has shown promise in selected cases. In this review, we summarize the progress in the understanding of the genetic landscape and the cellular and molecular basis of radioiodine refractory-DTC and ATC, as well as discuss the current treatment options and future therapeutic avenues.


Assuntos
Adenocarcinoma Folicular , Imunoterapia , Humanos , Imunoterapia/métodos , Adenocarcinoma Folicular/terapia , Adenocarcinoma Folicular/imunologia , Adenocarcinoma Folicular/genética , Neoplasias da Glândula Tireoide/terapia , Neoplasias da Glândula Tireoide/imunologia , Animais , Radioisótopos do Iodo/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico
2.
J Endourol ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38874511

RESUMO

Introduction and Objective: In early 2020, as the SARS-Cov-2 (COVID-19) pandemic progressed, many institutions limited nonurgent surgical care. This coincided with a decade-long trend of increasing percutaneous nephrolithotomy (PCNL) and ureteroscopy (URS) and decreasing shock wave lithotripsy (SWL) for surgical management of urolithiasis. Herein, we evaluate temporal stone surgery rates and surgeon volumes in the Medicare population and suggest how COVID-19 contributed to them. Methods: Retrospective analysis was conducted using the "Medicare Physician & Other Practitioners" database containing data from January 2013 to December 2021. Adult patients who underwent stone surgery were included. We evaluated surgeon characteristics and changes in case volumes over time adjusted for population. Results: In 2013, urologists performed 68,910 stone surgeries: SWL 42,903 (62%); URS 25,321 (37%); PCNL 686 (1%). Over the next 8 years, there was an average annual increase in URS (+13%) and PCNL (+13%) and decrease in SWL (-2%). In 2020, there was a 14% reduction in all stone cases: SWL (-25%); URS (-6%); PCNL (-8%). By 2021, case volumes recovered to pre-2020 levels, though SWL remained low: SWL 33,974 (34%); URS 64,541 (64%); PCNL 1764 (2%). From 2013 to 2021, the number of urologists performing SWL decreased (1718 to 1361) while URS and PCNL providers doubled (1,347 to 2,914 and 28 to 76, respectively). Conclusions: From 2013 to 2021, there was an increase in URS and PCNL and a decrease in SWL in the US Medicare population. The COVID-19 pandemic was associated with a decline in stone surgeries, particularly SWL. By 2021, PCNL and URS case numbers increased significantly with a smaller increase in SWL.

5.
J Otolaryngol Head Neck Surg ; 53: 19160216241263852, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38899627

RESUMO

BACKGROUND: Neck dissections (ND) are a routine procedure in head and neck oncology. Given the postoperative functional impact that some patients experience, it is imperative to identify and track quality of life (QoL) symptomatology to tailor each patient's therapeutic needs. To date, there is no validated French-Canadian questionnaire for this patient-population. We therefore sought to translate and validate the Neck Dissection Impairment Index (NDII) in Canadian French. METHODS: A 3-phased approach was used. Phase 1: The NDII was translated from English to Canadian French using a "forward and backward" translational technique following international guidelines. Phase 2: A cognitive debriefing session was held with 10 Canadian French-speaking otolaryngology patients to evaluate understandability and acceptability. Phase 3: The final version was administered prospectively to 30 patients with prior history of ND and 30 control patients. These patients were asked to complete the questionnaire 2 weeks after their first response. Test-retest reliability was calculated with Spearman's correlation. Internal consistency was elicited using Cronbach's alpha. RESULTS: NDII was successfully translated and validated to Canadian French. Cronbach's alpha revealed high internal consistency (0.92, lower 95% confidence limit 0.89). The correlation for test-retest validity were strong or very strong (0.61-0.91). CONCLUSION: NDII is an internationally recognized QoL tool for the identification of ND-related impairments. This validated Canadian French version will allow clinicians to adequately assess the surgery-related QoL effect of neck surgery in the French-speaking population, while allowing French institutions to conduct and/or participate in multisite clinical trials requiring the NDII as an outcome measure.


Assuntos
Neoplasias de Cabeça e Pescoço , Esvaziamento Cervical , Qualidade de Vida , Traduções , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Canadá , Inquéritos e Questionários , Neoplasias de Cabeça e Pescoço/cirurgia , Neoplasias de Cabeça e Pescoço/psicologia , Reprodutibilidade dos Testes , Idoso , Adulto , Estudos Prospectivos , Oncologia Cirúrgica
6.
Sci Rep ; 14(1): 13315, 2024 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858439

RESUMO

Exposure to high, marginally lethal doses or higher of ionizing radiation, either intentional or accidental, results in injury to various organs. Currently, there is only a limited number of safe and effective radiation countermeasures approved by US Food and Drug Administration for such injuries. These approved agents are effective for only the hematopoietic component of the acute radiation syndrome and must be administered only after the exposure event: currently, there is no FDA-approved agent that can be used prophylactically. The nutraceutical, gamma-tocotrienol (GT3) has been found to be a promising radioprotector of such exposure-related injuries, especially those of a hematopoietic nature, when tested in either rodents or nonhuman primates. We investigated the nature of injuries and the possible protective effects of GT3 within select organ systems/tissues caused by both non-lethal level (4.0 Gy), as well as potentially lethal level (5.8 Gy) of ionizing radiation, delivered as total-body or partial-body exposure. Results indicated that the most severe, dose-dependent injuries occurred within those organ systems with strong self-renewing capacities (e.g., the lymphohematopoietic and gastrointestinal systems), while in other tissues (e.g., liver, kidney, lung) endowed with less self-renewal, the pathologies noted tended to be less pronounced and less dependent on the level of exposure dose or on the applied exposure regimen. The prophylactic use of the test nutraceutical, GT3, appeared to limit the extent of irradiation-associated pathology within blood forming tissues and, to some extent, within the small intestine of the gastrointestinal tract. No distinct, global pattern of bodily protection was noted with the agent's use, although a hint of a possible radioprotective benefit was suggested not only by a lessening of apparent injury within select organ systems, but also by way of noting the lack of early onset of moribundity within select GT3-treated animals.


Assuntos
Suplementos Nutricionais , Protetores contra Radiação , Animais , Protetores contra Radiação/farmacologia , Vitamina E/farmacologia , Vitamina E/análogos & derivados , Síndrome Aguda da Radiação/prevenção & controle , Síndrome Aguda da Radiação/tratamento farmacológico , Síndrome Aguda da Radiação/patologia , Cromanos/farmacologia , Masculino , Lesões Experimentais por Radiação/prevenção & controle , Lesões Experimentais por Radiação/patologia , Macaca mulatta , Fígado/efeitos dos fármacos , Fígado/efeitos da radiação , Fígado/patologia
7.
Sci Rep ; 14(1): 13571, 2024 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-38866887

RESUMO

The identification and validation of radiation biomarkers is critical for assessing the radiation dose received in exposed individuals and for developing radiation medical countermeasures that can be used to treat acute radiation syndrome (ARS). Additionally, a fundamental understanding of the effects of radiation injury could further aid in the identification and development of therapeutic targets for mitigating radiation damage. In this study, blood samples were collected from fourteen male nonhuman primates (NHPs) that were exposed to 7.2 Gy ionizing radiation at various time points (seven days prior to irradiation; 1, 13, and 25 days post-irradiation; and immediately prior to the euthanasia of moribund (preterminal) animals). Plasma was isolated from these samples and was analyzed using a liquid chromatography tandem mass spectrometry approach in an effort to determine the effects of radiation on plasma proteomic profiles. The primary objective was to determine if the radiation-induced expression of specific proteins could serve as an early predictor for health decline leading to a preterminal phenotype. Our results suggest that radiation induced a complex temporal response in which some features exhibit upregulation while others trend downward. These statistically significantly altered features varied from pre-irradiation levels by as much as tenfold. Specifically, we found the expression of integrin alpha and thrombospondin correlated in peripheral blood with the preterminal stage. The differential expression of these proteins implicates dysregulation of biological processes such as hemostasis, inflammation, and immune response that could be leveraged for mitigating radiation-induced adverse effects.


Assuntos
Raios gama , Macaca mulatta , Proteômica , Animais , Raios gama/efeitos adversos , Masculino , Proteômica/métodos , Biomarcadores/sangue , Irradiação Corporal Total/efeitos adversos , Síndrome Aguda da Radiação/sangue , Síndrome Aguda da Radiação/etiologia , Proteínas Sanguíneas/análise , Proteínas Sanguíneas/metabolismo , Proteoma/análise , Proteoma/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-38780963

RESUMO

This case report describes the use of hyperpolarized magnetic resonance imaging (MRI) in a patient with head and neck squamous cell carcinoma (HNSCC) to demonstrate its translational viability.

9.
EMBO J ; 43(13): 2582-2605, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38806658

RESUMO

Necrosis in solid tumors is commonly associated with poor prognostic but how these lesions expand remains unclear. Studies have found that neutrophils associate with and contribute to necrosis development in glioblastoma by inducing tumor cell ferroptosis through transferring myeloperoxidase-containing granules. However, the mechanism of neutrophilic granule transfer remains elusive. We performed an unbiased small molecule screen and found that statins inhibit neutrophil-induced tumor cell death by blocking the neutrophilic granule transfer. Further, we identified a novel process wherein neutrophils are engulfed by tumor cells before releasing myeloperoxidase-containing contents into tumor cells. This neutrophil engulfment is initiated by integrin-mediated adhesion, and further mediated by LC3-associated phagocytosis (LAP), which can be blocked by inhibiting the Vps34-UVRAG-RUBCN-containing PI3K complex. Myeloperoxidase inhibition or Vps34 depletion resulted in reduced necrosis formation and prolonged mouse survival in an orthotopic glioblastoma mouse model. Thus, our study unveils a critical role for LAP-mediated neutrophil internalization in facilitating the transfer of neutrophilic granules, which in turn triggers tumor cell death and necrosis expansion. Targeting this process holds promise for improving glioblastoma prognosis.


Assuntos
Ferroptose , Glioblastoma , Neutrófilos , Fagocitose , Glioblastoma/patologia , Glioblastoma/metabolismo , Glioblastoma/imunologia , Glioblastoma/tratamento farmacológico , Animais , Neutrófilos/imunologia , Neutrófilos/metabolismo , Humanos , Camundongos , Ferroptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Necrose
10.
Radiat Res ; 202(1): 26-37, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38714310

RESUMO

BBT-059, a long-acting PEGylated interleukin-11 (IL-11) analog that is believed to have hematopoietic promoting and anti-apoptotic properties, is being developed as a potential radiation medical countermeasure (MCM) for hematopoietic acute radiation syndrome (H-ARS). This agent has been shown to improve survival in lethally irradiated mice. To further evaluate the drug's toxicity and safety profile, 12 naïve nonhuman primates (NHPs, rhesus macaques) were administered one of three doses of BBT-059 subcutaneously and were monitored for the next 21 days. Blood samples were collected throughout the study to assess the pharmacokinetics (PK) and pharmacodynamics (PD) of the drug as well as its effects on complete blood counts, cytokines, vital signs, and to conduct metabolomic studies. No adverse effects were detected in any treatment group during the study. Short-term changes in metabolomic profiles were present in all groups treated with BBT-059 beginning immediately after drug administration and reverting to near normal levels by the end of the study period. Several pathways and metabolites, particularly those related to inflammation and steroid hormone biosynthesis, were activated by BBT-059 administration. Taken together, these observations suggest that BBT-059 has a good safety profile for further development as a radiation MCM for regulatory approval for human use.


Assuntos
Macaca mulatta , Metabolômica , Polietilenoglicóis , Protetores contra Radiação , Animais , Protetores contra Radiação/farmacologia , Protetores contra Radiação/farmacocinética , Polietilenoglicóis/farmacocinética , Polietilenoglicóis/farmacologia , Polietilenoglicóis/química , Masculino , Interleucina-11 , Feminino , Metaboloma/efeitos dos fármacos , Metaboloma/efeitos da radiação , Síndrome Aguda da Radiação/tratamento farmacológico , Síndrome Aguda da Radiação/prevenção & controle
11.
Brain Res ; 1840: 149045, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38821335

RESUMO

Ferroptosis, an iron-dependent form of non-apoptotic regulated cell death, is induced by the accumulation of lipid peroxides on cellular membranes. Over the past decade, ferroptosis has emerged as a crucial process implicated in various physiological and pathological systems. Positioned as an alternative modality of cell death, ferroptosis holds promise for eliminating cancer cells that have developed resistance to apoptosis induced by conventional therapeutics. This has led to a growing interest in leveraging ferroptosis for cancer therapy across diverse malignancies. Gliomas are tumors arising from glial or precursor cells, with glioblastoma (GBM) being the most common malignant primary brain tumor that is associated with a dismal prognosis. This review provides a summary of recent advancements in the exploration of ferroptosis-sensitizing methods, with a specific focus on their potential application in enhancing the treatment of gliomas. In addition to summarizing the therapeutic potential, this review also discusses the intricate interplay of ferroptosis and its potential tumor-promoting roles within gliomas. Recognizing these dual roles is essential, as they could potentially complicate the therapeutic benefits of ferroptosis. Exploring strategies aimed at circumventing these tumor-promoting roles could enhance the overall therapeutic efficacy of ferroptosis in the context of glioma treatment.

12.
Cell Metab ; 36(6): 1335-1350.e8, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38701775

RESUMO

Perivascular collagen deposition by activated fibroblasts promotes vascular stiffening and drives cardiovascular diseases such as pulmonary hypertension (PH). Whether and how vascular fibroblasts rewire their metabolism to sustain collagen biosynthesis remains unknown. Here, we found that inflammation, hypoxia, and mechanical stress converge on activating the transcriptional coactivators YAP and TAZ (WWTR1) in pulmonary arterial adventitial fibroblasts (PAAFs). Consequently, YAP and TAZ drive glutamine and serine catabolism to sustain proline and glycine anabolism and promote collagen biosynthesis. Pharmacologic or dietary intervention on proline and glycine anabolic demand decreases vascular stiffening and improves cardiovascular function in PH rodent models. By identifying the limiting metabolic pathways for vascular collagen biosynthesis, our findings provide guidance for incorporating metabolic and dietary interventions for treating cardiopulmonary vascular disease.


Assuntos
Glutamina , Serina , Rigidez Vascular , Animais , Glutamina/metabolismo , Serina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fibroblastos/metabolismo , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/patologia , Humanos , Colágeno/metabolismo , Ratos
13.
Sci Data ; 11(1): 487, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734679

RESUMO

Radiation therapy (RT) is a crucial treatment for head and neck squamous cell carcinoma (HNSCC); however, it can have adverse effects on patients' long-term function and quality of life. Biomarkers that can predict tumor response to RT are being explored to personalize treatment and improve outcomes. While tissue and blood biomarkers have limitations, imaging biomarkers derived from magnetic resonance imaging (MRI) offer detailed information. The integration of MRI and a linear accelerator in the MR-Linac system allows for MR-guided radiation therapy (MRgRT), offering precise visualization and treatment delivery. This data descriptor offers a valuable repository for weekly intra-treatment diffusion-weighted imaging (DWI) data obtained from head and neck cancer patients. By analyzing the sequential DWI changes and their correlation with treatment response, as well as oncological and survival outcomes, the study provides valuable insights into the clinical implications of DWI in HNSCC.


Assuntos
Imagem de Difusão por Ressonância Magnética , Neoplasias de Cabeça e Pescoço , Humanos , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/radioterapia , Radioterapia Guiada por Imagem , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico por imagem , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia , Aceleradores de Partículas
14.
Clin Cancer Res ; 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691100

RESUMO

PURPOSE: Radiation-mediated immune suppression limits efficacy and is a barrier in cancer therapy. Radiation induces negative regulators of tumor immunity including regulatory T cells (Treg). Mechanisms underlying Treg infiltration after radiotherapy (RT) are poorly defined. Given that dendritic cells (cDC) maintain Treg we sought to identify and target cDC signaling to block Treg infiltration after radiation. EXPERIMENTAL DESIGN: Transcriptomics and high dimensional flow cytometry revealed changes in murine tumor cDC that not only mediate Treg infiltration after RT, but associate with worse survival in human cancer datasets. Antibodies perturbing a cDC-CCL22-Treg axis were tested in syngeneic murine tumors. A prototype interferon-anti-epidermal growth factor receptor fusion protein (αEGFR-IFNα) was examined to block Treg infiltration and promote a CD8+ T cell response after RT. RESULTS: Radiation expands a population of mature cDC1 enriched in immunoregulatory markers that mediates Treg infiltration via the Treg-recruiting chemokine CCL22. Blocking CCL22 or Treg depletion both enhanced RT efficacy. αEGFR-IFNα blocked cDC1 CCL22 production while simultaneously inducing an antitumor CD8+ T cell response to enhance RT efficacy in multiple EGFR-expressing murine tumor models, including following systemic administration. CONCLUSIONS: We identify a previously unappreciated cDC mechanism mediating Treg tumor infiltration after RT. Our findings suggest blocking the cDC1-CCL22-Treg axis augments RT efficacy. αEGFR-IFNα added to RT provided robust antitumor responses better than systemic free interferon administration, and may overcome clinical limitations to interferon therapy. Our findings highlight the complex behavior of cDC after RT and provide novel therapeutic strategies for overcoming RT-driven immunosuppression to improve RT efficacy.

15.
Am J Emerg Med ; 82: 82-87, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38820810

RESUMO

Dengue is an arbovirus transmitted by the Aedes spp. mosquito. Approximately 390 million infections occur annually per World Health Organization estimates, with significant increases in infections throughout the last decade. The disease is endemic in warmer climates throughout the world, though cases may also be imported to non-endemic regions by returning travelers. Patients experience a wide variety of symptoms ranging from asymptomatic infection to severe disease requiring critical care. Emergency clinicians should consider the diagnosis of dengue in patients from endemic areas presenting with a flu-like illness, rash, and evidence of bleeding.

16.
Urology ; 188: 47-53, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38648946

RESUMO

OBJECTIVE: To identify the need for repeat stone surgery in patients with and without bowel disease. Few studies have compared risks between different types of bowel disease and whether their need for repeat stone surgery differs. METHODS: From our IRB-approved study, we identified patients with and without bowel disease. We categorized patients' bowel disease into 4 categories: inflammatory bowel disease (IBD), bypass procedures, bowel resection, and bowel disease not otherwise specified (eg, irritable bowel syndrome, celiac disease). Differences between patient demographics, stone disease, and recurrent stone events for patients with and without bowel disease were compared using univariate and multivariate survival analyses (SPSS 25). RESULTS: Of all surgical stone patients (2011), 484 (24%) had some type of bowel disease. Compared to patients without bowel disease, patients with bowel disease presented with stones at an older age (62.2 ± 14.5 vs 58.4 ± 15.3 years; P <.001) and were more likely to be female (56 vs 46%; P <.001). Patients with bowel disease required more repeat stone surgery than those without bowel disease (31% vs 23%, P <.001). In multivariate analysis, patients with bypass and bowel resection were associated with more repeat surgery than patients without bowel disease (P <.001, P = .002, respectively). Patients with IBD and bowel disease not otherwise specified did not have higher risk for repeat surgery than patients without bowel disease. CONCLUSION: Surgical stone patients with bowel disease, specifically those with prior bowel resection and bypass, had a higher risk of repeat stone surgery over time than stone formers without bowel disease. DATA AVAILABILITY: The data sets generated and analyzed during the current study are available from the corresponding author on reasonable request.


Assuntos
Reoperação , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Reoperação/estatística & dados numéricos , Fatores de Tempo , Estudos Retrospectivos , Idoso , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/cirurgia , Adulto , Recidiva , Fatores de Risco , Medição de Risco/métodos
17.
Eur J Heart Fail ; 26(4): 707-729, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38639017

RESUMO

Pulmonary hypertension (PH) associated with left heart failure (LHF) (PH-LHF) is one of the most common causes of PH. It directly contributes to symptoms and reduced functional capacity and negatively affects right heart function, ultimately leading to a poor prognosis. There are no specific treatments for PH-LHF, despite the high number of drugs tested so far. This scientific document addresses the main knowledge gaps in PH-LHF with emphasis on pathophysiology and clinical trials. Key identified issues include better understanding of the role of pulmonary venous versus arteriolar remodelling, multidimensional phenotyping to recognize patient subgroups positioned to respond to different therapies, and conduct of rigorous pre-clinical studies combining small and large animal models. Advancements in these areas are expected to better inform the design of clinical trials and extend treatment options beyond those effective in pulmonary arterial hypertension. Enrichment strategies, endpoint assessments, and thorough haemodynamic studies, both at rest and during exercise, are proposed to play primary roles to optimize early-stage development of candidate therapies for PH-LHF.


Assuntos
Insuficiência Cardíaca , Hipertensão Pulmonar , Circulação Pulmonar , Função Ventricular Direita , Humanos , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/terapia , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/terapia , Função Ventricular Direita/fisiologia , Circulação Pulmonar/fisiologia
18.
Head Neck ; 46(6): 1533-1541, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38595113

RESUMO

The osteocutaneous radial forearm free flap (OCRFFF) is a versatile flap with the ability to reconstruct complex defects. We detail the techniques necessary to harvest an OCRFFF, including an outline on making 90-degree osteotomies to maximize bone harvest. In this pictorial essay, we provide illustrations of the anatomy and surgical techniques necessary for OCRFFF harvest. Detailed discussion is provided on how to protect the perforators to the bone and the approach to making osteotomies in a 90-degree fashion. The approach for prophylactic plating of the radius to prevent radius fractures is outlined. A case presentation on the real-life utilization of this flap is included. The OCRFFF is an excellent head and neck reconstructive option. While there are limitations to its use for patients requiring dental rehabilitation or long/anterior mandibular defects, for the right patient and indication it has shown great success in reconstructive efforts.


Assuntos
Antebraço , Retalhos de Tecido Biológico , Procedimentos de Cirurgia Plástica , Feminino , Humanos , Transplante Ósseo/métodos , Carcinoma de Células Escamosas/cirurgia , Antebraço/cirurgia , Neoplasias de Cabeça e Pescoço/cirurgia , Osteotomia/métodos , Procedimentos de Cirurgia Plástica/métodos , Rádio (Anatomia)/cirurgia , Coleta de Tecidos e Órgãos/métodos , Idoso de 80 Anos ou mais
20.
bioRxiv ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38659742

RESUMO

Background: Phospholamban (PLN) is a key regulator of cardiac function connecting adrenergic signaling and calcium homeostasis. The R9C mutation of PLN is known to cause early onset dilated cardiomyopathy (DCM) and premature death, yet the detailed mechanisms underlie the pathologic remodeling process are not well defined in human cardiomyocytes. The aim of this study is to unravel the role of PLN R9C in DCM and identify potential therapeutic targets. Methods: PLN R9C knock-in (KI) and patient-specific induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) were generated and comprehensively examined for their expression profile, contractile function, and cellular signaling under both baseline conditions and following functional challenges. Results: PLN R9C KI iPSC-CMs exhibited near-normal morphology and calcium handling, slightly increased contractility, and an attenuated response to ß-adrenergic activation compared to wild-type (WT) cells. However, treatment with a maturation medium (MM) has induced fundamentally different remodeling in the two groups: while it improved the structural integrity and functional performance of WT cells, the same treatment result in sarcomere disarrangement, calcium handling deficiency, and further disrupted adrenergic signaling in PLN R9C KI cells. To understand the mechanism, transcriptomic analysis showed the enrichment of protein homeostasis signaling pathways specifically in PLN R9C KI cells in response to the MM treatment and increased contractile demands. Further studies also indicated elevated ROS levels, interrupted autophagic flux, and increased pentamer PLN aggregation in functionally challenged KI cells. These results were further confirmed in patient-specific iPSC-CM models, suggesting that functional stresses exacerbate the deficiencies in PLN R9C cells through disrupting protein homeostasis. Indeed, treating stressed patient cells with autophagy-accelerating reagents, such as metformin and rapamycin, has restored autophagic flux, mitigated sarcomere disarrangement, and partially rescued ß-adrenergic signaling and cardiac function. Conclusions: PLN R9C leads to a mild increase of calcium recycling and contractility. Functional challenges further enhanced contractile and proteostasis stress, leading to autophagic overload, structural remodeling, and functional deficiencies in PLN R9C cardiomyocytes. Activation of autophagy signaling partially rescues these effects, revealing a potential therapeutic target for DCM patients with the PLN R9C mutation. Graphic abstracts: A graphic abstract is available for this article.

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