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1.
J Nucl Med ; 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388516

RESUMO

Artificial intelligence (AI) may decrease 18F-FDG PET/CT-based gross tumor volume (GTV) delineation variability and automate tumor-volume-derived image biomarker extraction. Hence, we aimed to identify and evaluate promising state-of-the-art deep learning methods for head and neck cancer (HNC) PET GTV delineation. Methods: We trained and evaluated deep learning methods using retrospectively included scans of HNC patients referred for radiotherapy between January 2014 and December 2019 (ISRCTN16907234). We used 3 test datasets: an internal set to compare methods, another internal set to compare AI-to-expert variability and expert interobserver variability (IOV), and an external set to compare internal and external AI-to-expert variability. Expert PET GTVs were used as the reference standard. Our benchmark IOV was measured using the PET GTV of 6 experts. The primary outcome was the Dice similarity coefficient (DSC). ANOVA was used to compare methods, a paired t test was used to compare AI-to-expert variability and expert IOV, an unpaired t test was used to compare internal and external AI-to-expert variability, and post hoc Bland-Altman analysis was used to evaluate biomarker agreement. Results: In total, 1,220 18F-FDG PET/CT scans of 1,190 patients (mean age ± SD, 63 ± 10 y; 858 men) were included, and 5 deep learning methods were trained using 5-fold cross-validation (n = 805). The nnU-Net method achieved the highest similarity (DSC, 0.80 [95% CI, 0.77-0.86]; n = 196). We found no evidence of a difference between expert IOV and AI-to-expert variability (DSC, 0.78 for AI vs. 0.82 for experts; mean difference of 0.04 [95% CI, -0.01 to 0.09]; P = 0.12; n = 64). We found no evidence of a difference between the internal and external AI-to-expert variability (DSC, 0.80 internally vs. 0.81 externally; mean difference of 0.004 [95% CI, -0.05 to 0.04]; P = 0.87; n = 125). PET GTV-derived biomarkers of AI were in good agreement with experts. Conclusion: Deep learning can be used to automate 18F-FDG PET/CT tumor-volume-derived imaging biomarkers, and the deep-learning-based volumes have the potential to assist clinical tumor volume delineation in radiation oncology.

2.
J Cell Biol ; 223(1)2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37991810

RESUMO

Oxysterol binding protein (OSBP) extracts cholesterol from the ER to deliver it to the TGN via counter exchange and subsequent hydrolysis of the phosphoinositide PI(4)P. Here, we show that this pathway is essential in polarized epithelial cells where it contributes not only to the proper subcellular distribution of cholesterol but also to the trans-Golgi sorting and trafficking of numerous plasma membrane cargo proteins with apical or basolateral localization. Reducing the expression of OSBP, blocking its activity, or inhibiting a PI4Kinase that fuels OSBP with PI(4)P abolishes the epithelial phenotype. Waves of cargo enrichment in the TGN in phase with OSBP and PI(4)P dynamics suggest that OSBP promotes the formation of lipid gradients along the TGN, which helps cargo sorting. During their transient passage through the trans-Golgi, polarized plasma membrane proteins get close to OSBP but fail to be sorted when OSBP is silenced. Thus, OSBP lipid exchange activity is decisive for polarized cargo sorting and distribution in epithelial cells.


Assuntos
Colesterol , Retículo Endoplasmático , Células Epiteliais , Complexo de Golgi , Receptores de Esteroides , Movimento Celular , Colesterol/metabolismo , Células Epiteliais/metabolismo , Complexo de Golgi/metabolismo , Proteínas de Membrana/metabolismo , Fosfatidilinositóis/metabolismo , Humanos , Animais , Cães , Células A549 , Células Madin Darby de Rim Canino , Retículo Endoplasmático/metabolismo , Receptores de Esteroides/metabolismo
3.
Int J Gen Med ; 16: 5425-5437, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38021042

RESUMO

Background: The clinical relevance of thrombophilic laboratory factors, especially the "mild" ones, and the need for their screening is not generally recommended in venous (VTE) and/or arterial (ATE) thromboembolism. Methods: Our aim was to investigate possible associations between comorbidities and 16 inherited/acquired "severe" and "mild" laboratory thrombophilic factors (detailed in introduction) in patients (n=348) with VTE/ATE without a serious trigger (high-risk surgical intervention, active cancer and/or chemo-radiotherapy). Cases with VTE/ATE were enrolled when the thrombotic event occurred under the age of 40, in case of positive family history, recurrent thromboembolism, idiopathic event or unusual location. Patients without a detailed thrombophilia screening or who suffered from both ATE/VTE were excluded to find potential distinct thrombosis type specific thrombophilic risks. The possible role of "mild" factor accumulation was also investigated in VTE (n=266). Results: Elevation of factor VIII clotting activity was associated with VTE rather than ATE. Varicose veins together with postthrombotic syndrome were strongly related to several "mild" factors. Besides "severe" we found that the "mild" thrombophilic factors were also strongly associated with VTE/ATE. Comorbidities/conditions such as diabetes and smoking were generally associated with hyperlipidemia; moreover, both had a correlation with lipoprotein (a) in VTE. We also revealed an important contribution of "mild" factors in increasing trends of several types and localizations of VTE. Conclusion: In summary, besides the "severe" thrombophilic factors, the "mild" ones also seem to play a non-negligible role in the manifestation of thrombosis, especially in combination. Therefore, an extended screening might be useful in the personalized recommendation of antithrombotic prophylaxis.

4.
J Med Chem ; 66(20): 14208-14220, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37795600

RESUMO

Schweinfurthins (SWs) are naturally occurring prenylated stilbenes with promising anticancer properties. They act through a novel mechanism of action similar to that of other families of natural compounds. Their known target, oxysterol-binding protein (OSBP), plays a crucial role in controlling the intracellular distribution of cholesterol. We synthesized 15 analogues of SWs and demonstrated for the first time that their cytotoxicity as well as that of natural derivatives correlates with their affinity for OSBP. Through this extensive SAR study, we selected one synthetic analogue obtained in one step from SW-G. Using its fluorescence properties, we showed that this compound recapitulates the effect of natural SW-G in cells and confirmed that it leads to cell death via the same mechanism. Finally, after pilot PK experiments, we provided the first evidence of its in vivo efficacy in combination with temozolomide in a patient-derived glioblastoma xenograft model.


Assuntos
Oxisteróis , Receptores de Esteroides , Humanos , Receptores de Esteroides/metabolismo , Colesterol/metabolismo
5.
Int J Surg Case Rep ; 112: 108914, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37832360

RESUMO

INTRODUCTION AND IMPORTANCE: Ganglioneuromas are extremely rare, slow-growing, benign tumors that arising from Schwann cells, ganglion cells, and neuronal or fibrous tissue. Their malignant degeneration occurs very rarely, complete surgical removal is recommended to eliminate possible symptoms or to prevent possible malignant transformation. Reviewing the literature, there is currently insufficient data available on laparoscopic resection of retroperitoneal ganglioneuromas. CASE PRESENTATION: 20-year-old young woman with no previous medical history or regular medication use complaints of abdominal pain. Abdominal CT scan found a cystic mass measuring up to 50 mm in diameter with a thick fluid density and no contrast accumulation, was identified in the porta hepatis region extrahepatically. Ultrasound-guided biopsy was performed, histopathological finding revealed mature benign neurogenic tumor tissue consisting of mature ganglion cells, mature Schwann cells, and branching stroma. CLINICAL DISCUSSION: A laparoscopic surgery was performed, the 5 cm large tumor was excised from the hepatoduodenal ligament. The tumor was removed from the region of the inferior caval vein, portal vein, and the common and proper hepatic arteries. Final histological diagnosis is ganglioneuroma of the hepatoduodenal ligament. After uneventful postoperative period, the patient was discharged home on the 6th day. CONCLUSIONS: Retroperitoneal tumors were previously excised during laparotomy. However, in recent decades, with the development of laparoscopic surgical techniques and tools, laparoscopic removal of some retroperitoneal tumors seems to be the ideal approach. The use of laparoscopy improves visibility of the relationship of the tumor to the surrounding, often vital, structures. Based on a review of the international literature and our own experience, laparoscopic ganglioneuroma resection is the recommended procedure with careful patient selection, as well as appropriate preoperative imaging and diagnostics, and with adequate expertise.

6.
Transplant Proc ; 54(9): 2578-2583, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36400590

RESUMO

The surgical aspect of kidney transplant can be the surgical technique itself or the use of reconstruction techniques in the case of a complication requiring reoperation. In our study, we examined particularly surgical techniques and reconstruction options for ureteral anastomoses. Data from patients who underwent kidney transplant from 2010 to 2020 (N = 433) were examined retrospectively at follow-up of at least 1 year. We sought an association between the type of ureteral anastomoses and parameters considered to be risk factors based on literature data. We did not note the complicated cases that solved spontaneously and only selected cases where the ureteral anastomosis complication (UAcomp) needed urologic, radiological, or surgical intervention. In a smaller group, we examined the correlation between BK polyomavirus and ureteral stenosis. A total of 9.2% (n = 40) of patients developed UAcomp, 67.5% (n = 27) of whom required reoperation. In complicated cases, the rate of primary ureteral anastomosis type was 60.0% (n = 24) ureteroneocystostomy (UNS) and 40.0% (n = 16) ureteroureterostomy (UU) (P = .184). After UNS, 7.7% (n = 17) of cases required reoperation, and this rate was 4.7% (n = 10) after UU (P = .164). After treatment of the UAcomp, 95.0% (n = 38) of the patients were discharged with a functioning graft, and 5.0% (n = 2) required graftectomy. Complications of ureteral anastomosis with appropriate interventions results in good graft function. The type of ureteral anastomosis is not significantly associated with UAcomp. It is important that the operating surgeon is well versed in UNS and UU techniques to be able to adapt to any situation, be it primary surgery or reoperation.


Assuntos
Transplante de Rim , Ureter , Obstrução Ureteral , Humanos , Transplante de Rim/efeitos adversos , Transplante de Rim/métodos , Estudos Retrospectivos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Ureter/cirurgia , Obstrução Ureteral/etiologia , Resultado do Tratamento
7.
Int J Nanomedicine ; 17: 3079-3096, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35859731

RESUMO

Background: Multidrug resistance is a common reason behind the failure of chemotherapy. Even if the therapy is effective, serious adverse effects might develop due to the low specificity and selectivity of antineoplastic agents. Mesoporous silica nanoparticles (MSNs) are promising materials for tumor-targeting and drug-delivery due to their small size, relatively inert nature, and extremely large specific surfaces that can be functionalized by therapeutic and targeting entities. We aimed to create a fluorescently labeled MSN-based drug-delivery system and investigate their internalization and drug-releasing capability in drug-sensitive MCF-7 and P-glycoprotein-overexpressing multidrug-resistant MCF-7 KCR cancer cells. Methods and Results: To track the uptake and subcellular distribution of MSNs, particles with covalently coupled red fluorescent Rhodamine B (RhoB) were produced (RhoB@MSNs). Both MCF-7 and MCF-7 KCR cells accumulated a significant amount of RhoB@MSNs. The intracellular RhoB@MSN concentrations did not differ between sensitive and multidrug-resistant cells and were kept at the same level even after cessation of RhoB@MSN exposure. Although most RhoB@MSNs resided in the cytoplasm, significantly more RhoB@MSNs co-localized with lysosomes in multidrug-resistant cells compared to sensitive counterparts. To examine the drug-delivery capability of these particles, RhoB@Rho123@MSNs were established, where RhoB-functionalized nanoparticles carried green fluorescent Rhodamine 123 (Rho123) - a P-glycoprotein substrate - as cargo within mesopores. Significantly higher Rho123 fluorescence intensity was detected in RhoB@Rho123@MSN-treated multidrug-resistant cells than in free Rho123-exposed counterparts. The exceptional drug-delivery potential of MSNs was further verified using Mitomycin C (MMC)-loaded RhoB@MSNs (RhoB@MMC@MSNs). Exposures to RhoB@MMC@MSNs significantly decreased the viability not only of drug-sensitive but of multidrug-resistant cells and the elimination of MDR cells was significantly more robust than upon free MMC treatments. Conclusion: The efficient delivery of Rho123 and MMC to multidrug-resistant cells via MSNs, the amplified and presumably prolonged intracellular drug concentration, and the consequently enhanced cytotoxic effects envision the enormous potential of MSNs to defeat multidrug-resistant cancer.


Assuntos
Antineoplásicos , Nanopartículas , Neoplasias , Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Antineoplásicos/uso terapêutico , Doxorrubicina , Portadores de Fármacos/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Humanos , Nanopartículas/ultraestrutura , Neoplasias/tratamento farmacológico , Porosidade , Dióxido de Silício/farmacologia
8.
Int J Mol Sci ; 23(2)2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35055024

RESUMO

As an emerging new class, metal nanoparticles and especially silver nanoparticles hold great potential in the field of cancer biology. Due to cancer-specific targeting, the consequently attenuated side-effects and the massive anti-cancer features render nanoparticle therapeutics desirable platforms for clinically relevant drug development. In this review, we highlight those characteristics of silver nanoparticle-based therapeutic concepts that are unique, exploitable, and achievable, as well as those that represent the critical hurdle in their advancement to clinical utilization. The collection of findings presented here will describe the features that distinguish silver nanoparticles from other anti-cancer agents and display the realistic opportunities and implications in oncotherapeutic innovations to find out whether cancer therapy by silver nanoparticles is fiction or reality.


Assuntos
Antineoplásicos/administração & dosagem , Nanopartículas Metálicas , Nanomedicina , Neoplasias/tratamento farmacológico , Prata , Animais , Antineoplásicos/uso terapêutico , Técnicas de Química Sintética , Estudos Clínicos como Assunto , Terapia Combinada , Gerenciamento Clínico , Portadores de Fármacos/química , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Desenvolvimento de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Humanos , Nanopartículas Metálicas/química , Nanomedicina/métodos , Nanotecnologia , Prata/química , Resultado do Tratamento
9.
Nucl Med Commun ; 43(5): 549-559, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35081091

RESUMO

OBJECTIVES: The aim of this study was to assess the test-retest repeatability and interobserver variation in healthy tissue (HT) metabolism using 2-deoxy-2-[18F]fluoro-d-glucose (18F-FDG) PET/computed tomography (PET/CT) of the thorax in lung cancer patients. METHODS: A retrospective analysis was conducted in 22 patients with non-small cell lung cancer who had two PET/CT scans of the thorax performed 3 days apart with no interval treatment. The maximum, mean and peak standardized uptake values (SUVs) in different HTs were measured by a single observer for the test-retest analysis and two observers for interobserver variation. Bland-Altman plots were used to assess the repeatability and interobserver variation. Intrasubject variability was evaluated using within-subject coefficients of variation (wCV). RESULTS: The wCV of test-retest SUVmean measurements in mediastinal blood pool, bone marrow, skeletal muscles and lungs was less than 20%. The left ventricle (LV) showed higher wCV (>60%) in all SUV parameters with wide limits of repeatability. High interobserver agreement was found with wCV of less than 10% in SUVmean of all HT, but up to 22% was noted in the LV. CONCLUSION: HT metabolism is stable in a test-retest scenario and has high interobserver agreement. SUVmean was the most stable metric in organs with low FDG uptake and SUVpeak in HTs with moderate uptake. Test-retest measurements in LV were highly variable irrespective of the SUV parameters used for measurements.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Fluordesoxiglucose F18/metabolismo , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/metabolismo , Variações Dependentes do Observador , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Tórax/diagnóstico por imagem , Tórax/metabolismo
10.
Front Endocrinol (Lausanne) ; 12: 727320, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34707568

RESUMO

Background: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a novel coronavirus that has caused a worldwide pandemic. The majority of medullary thyroid cancers present as a thyroid nodule. At the time of diagnosis, cervical lymph nodes and distant metastases are frequently detected. Case Report: Here, we present a case of a 46-year-old man with coronavirus disease (COVID) pneumonia, who had persistently high serum procalcitonin levels despite normal C-reactive protein levels. The attending infectologist happened to be a colleague who spent some time, as part of her internal medicine rotation, in the Endocrine Ward and recalled that medullary thyroid cancer might be the cause. This led to the timely workup and treatment of the medullary cancer.


Assuntos
COVID-19/complicações , Carcinoma Neuroendócrino/sangue , Carcinoma Neuroendócrino/diagnóstico , Endocrinologia/métodos , Pró-Calcitonina/sangue , Neoplasias da Glândula Tireoide/sangue , Neoplasias da Glândula Tireoide/diagnóstico , Biomarcadores Tumorais/sangue , Proteína C-Reativa/biossíntese , Carcinoma Neuroendócrino/complicações , Humanos , Achados Incidentais , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Neoplasias da Glândula Tireoide/complicações , Nódulo da Glândula Tireoide
11.
Orv Hetil ; 162(26): 1038-1051, 2021 06 27.
Artigo em Húngaro | MEDLINE | ID: mdl-34175833

RESUMO

Összefoglaló. Bevezetés: Veseátültetést követoen a graft és a beteg túlélésére hatással lehetnek a posztoperatív intervenciót igénylo szövodmények. Fontos szempont a mutéttechnikai eredményesség monitorozása. Többek között az irodalomban számos lehetoség ismert a veseátültetés sarokpontjának számító ureteranastomosis elkészítésére is, de az éranastomosisok technikája szintén dönto lehet. Célkituzés és módszer: Retrospektíven vizsgáltuk a 2010 és 2020 között végzett veseátültetéseket a Debreceni Egyetem Sebészeti Klinikáján. Célul tuztük ki a sebészeti szövodmények vizsgálatát, melyeket rendszereztünk, a módosított Clavien-féle beosztás alapján. A legnagyobb figyelmet az ureteranastomosisokra fordítottuk. Minden betegnél az adott kategóriában legsúlyosabb szövodményt vettük alapul a beosztáshoz. A minimális utánkövetési ido 1 év volt. Az adatokat az SPSS statisztikai program segítségével elemeztük. Eredmények: A vizsgált periódusban 406 veseátültetés történt, melybol 24,4% (n = 99) vesetranszplantáltnál alakult ki intervenciós (sebészeti, radiológiai, urológiai) szövodmény. A betegek átlagéletkora 49,5 ± 13,7 év, 60,8% férfi volt. A kumulatív mortalitás 10,1% volt. Grade 4-es szövodmény a betegek 6,9%-ánál (n = 28), Grade 3-as a 6,7%-ánál (n = 27), Grade 2-es a 3%-ánál (n = 12), Grade 1-es a 7,9%-ánál (n = 32) jelentkezett. A veseátültetés után 20,4%-ban (n = 83) alakult ki késon induló graftfunkció. Következtetés: A legenyhébb kategóriába (Grade 1.) került a legtöbb beteg, a szövodmények jelentos része sebészi, intervenciós radiológiai és urológiai közremuködéssel megoldható volt. Az ureteranastomosisok mutéti technikája és a releváns szövodmények kialakulása között nincs szignifikáns összefüggés. Megfelelo és idoben alkalmazott korrekciós kezelés mellett a graft- és betegtúlélést nem rontja szignifikánsan az enyhe és középsúlyos (Grade 1-3.) szövodmények kialakulása. Orv Hetil. 2021; 162(26): 1038-1051. INTRODUCTION: Complications associated with postoperative intervention may affect graft and patient survival after kidney transplantation. Monitoring the effectiveness of surgery is an important aspect. Ureter anastomosis can be the pivot of kidney transplant, the same as vascular anastomosis, so efficiency of the surgical technique is important to follow up. OBJECTIVE AND METHOD: We retrospectively examined kidney transplants performed between 2010 and 2020 at the Department of Surgery of the University of Debrecen. Data were analyzed by the SPSS statistical program. We aimed to investigate surgical complications, which were systematized based on the modified Clavien classification. In one patient, the most severe complication was used as the basis for the schedule. The minimum follow-up time was 1 year. RESULTS: 406 kidney transplants were performed in the examined period, of which 24.4% (n = 99) developed renal transplant complications (surgical, radiological, urological). The mean age of the patients was 49.5 ± 13.7 years, and 60.8% were male. The cumulative mortality was 10.1%. Grade 4 complication developed in 6.9% (n = 28) of the recipients, Grade 3 in 6.7% (n = 27), Grade 2 in 3% (n = 12), and Grade 1 in 7.9% (n = 32). 20.4% of the recipients had delayed graft function. CONCLUSION: The Grade 1 group had the biggest case number, so a significant part of the complications could be solved with the help of interventional radiology and urologists. There is no significant association between the surgical technique of ureteral anastomoses and the development of related complications. With appropriate therapy, graft and patient survival are not significantly impaired by the development of Grade 1-3 complications. Orv Hetil. 2021; 162(26): 1038-1051.


Assuntos
Transplante de Rim , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos
12.
Chemosphere ; 251: 126419, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32171133

RESUMO

Due to their release into the environment, zinc oxide nanoparticles (ZnO NPs) may come in contact with plants. In elevated concentrations, ZnO NPs induce reactive oxygen species (ROS) production, but the metabolism of reactive nitrogen species (RNS) and the consequent nitro-oxidative signalling has not been examined so far. In this work, Brassica napus and Brassica juncea seedlings were treated with chemically synthetized ZnO NPs (∼8 nm, 0, 25 or 100 mg/L). At low dose (25 mg/L) ZnO NP exerted a positive effect, while at elevated concentration (100 mg/L) it was toxic to both species. Additionally, B. juncea was more tolerant to ZnO NPs than B. napus. The ZnO NPs could enter the root cells due to their small (∼8 nm) size which resulted in the release of Zn2+ and subsequently increased Zn2+ content in the plant organs. ZnO NPs disturbed superoxide radical and hydrogen peroxide homeostasis and modulated ROS metabolic enzymes (NADPH oxidase, superoxide dismutase, ascorbate peroxidase) and non-enzymatic antioxidants (ascorbate and glutathione) inducing similar changes in oxidative signalling in both Brassica species. The homeostasis of RNS (nitric oxide, peroxynitrite and S-nitrosoglutathione) was also altered by ZnO NPs; however, changes in nitrosative signalling proved to be different in the examined species. Moreover, ZnO NPs triggered changes in protein carbonylation and nitration. These results suggest that ZnO NPs induce changes in nitro-oxidative signalling which may contribute to ZnO NP toxicity. Furthermore, difference in ZnO NP tolerance of Brassica species is more likely related to nitrosative than to oxidative signalling.


Assuntos
Brassica/fisiologia , Nanopartículas/toxicidade , Óxido de Zinco/toxicidade , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Brassica napus/metabolismo , Glutationa/metabolismo , Mostardeira/metabolismo , Nanopartículas/química , Oxirredução , Raízes de Plantas/metabolismo , Espécies Reativas de Nitrogênio , Espécies Reativas de Oxigênio/metabolismo , Plântula/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Zinco/química , Óxido de Zinco/química
13.
J Biol Chem ; 295(13): 4277-4288, 2020 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-32075908

RESUMO

ORPphilins are bioactive natural products that strongly and selectively inhibit the growth of some cancer cell lines and are proposed to target intracellular lipid-transfer proteins of the oxysterol-binding protein (OSBP) family. These conserved proteins exchange key lipids, such as cholesterol and phosphatidylinositol 4-phosphate (PI(4)P), between organelle membranes. Among ORPphilins, molecules of the schweinfurthin family interfere with intracellular lipid distribution and metabolism, but their functioning at the molecular level is poorly understood. We report here that cell line sensitivity to schweinfurthin G (SWG) is inversely proportional to cellular OSBP levels. By taking advantage of the intrinsic fluorescence of SWG, we followed its fate in cell cultures and show that its incorporation at the trans-Golgi network depends on cellular abundance of OSBP. Using in vitro membrane reconstitution systems and cellular imaging approaches, we also report that SWG inhibits specifically the lipid transfer activity of OSBP. As a consequence, post-Golgi trafficking, membrane cholesterol levels, and PI(4)P turnover were affected. Finally, using intermolecular FRET analysis, we demonstrate that SWG directly binds to the lipid-binding cavity of OSBP. Collectively these results describe SWG as a specific and intrinsically fluorescent pharmacological tool for dissecting OSBP properties at the cellular and molecular levels. Our findings indicate that SWG binds OSBP with nanomolar affinity, that this binding is sensitive to the membrane environment, and that SWG inhibits the OSBP-catalyzed lipid exchange cycle.


Assuntos
Transporte Biológico/efeitos dos fármacos , Lipídeos/genética , Receptores de Esteroides/metabolismo , Estilbenos/metabolismo , Proteínas de Transporte/química , Proteínas de Transporte/genética , Retículo Endoplasmático/química , Retículo Endoplasmático/genética , Fluorescência , Humanos , Lipídeos/química , Ligação Proteica/genética , Transporte Proteico/genética , Receptores de Esteroides/química , Estilbenos/química , Rede trans-Golgi/química , Rede trans-Golgi/genética
14.
Nanomaterials (Basel) ; 10(1)2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31963267

RESUMO

Radiosensitizing agents are capable of augmenting the damage of ionizing radiation preferentially on cancer cells, thereby increasing the potency and the specificity of radiotherapy. Metal-based nanoparticles have recently gathered ground in radio-enhancement applications, owing to their exceptional competence in amplifying the cell-killing effects of irradiation. Our aim was to examine the radiosensitizing performance of gold nanoparticles (AuNPs) and the chromatin-modifying histone deacetylase inhibitor suberoylanilide hydroxamic acid (SAHA) alone and in combination. We observed that the colony-forming capability of cancer cells decreased significantly and the DNA damage, detected by γH2AX immunostaining, was substantially greater after combinational treatments than upon individual drug exposures followed by irradiation. Synergistic radiosensitizing effects of AuNPs and SAHA were proven on various cell lines, including radioresistant A549 and DU-145 cancer cells. 3D cultures often manifest radio- and drug-resistance, nevertheless, AuNPs in combination with SAHA could effectively enhance the potency of irradiation as the number of viable cells decreased significantly when spheroids received AuNP + SAHA prior to radiotherapy. Our results imply that a relaxed chromatin structure induced by SAHA renders the DNA of cancerous cells more susceptible to the damaging effects of irradiation-triggered, AuNP-released reactive electrons. This feature of AuNPs should be exploited in multimodal treatment approaches.

15.
J Nanobiotechnology ; 18(1): 18, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31964403

RESUMO

BACKGROUND: Although accumulating evidence suggests that the crosstalk between malignant cells and cancer-associated fibroblasts (CAFs) actively contributes to tumour growth and metastatic dissemination, therapeutic strategies targeting tumour stroma are still not common in the clinical practice. Metal-based nanomaterials have been shown to exert excellent cytotoxic and anti-cancerous activities, however, their effects on the reactive stroma have never been investigated in details. Thus, using feasible in vitro and in vivo systems to model tumour microenvironment, we tested whether the presence of gold, silver or gold-core silver-shell nanoparticles exerts anti-tumour and metastasis suppressing activities by influencing the tumour-supporting activity of stromal fibroblasts. RESULTS: We found that the presence of gold-core silver-shell hybrid nanomaterials in the tumour microenvironment attenuated the tumour cell-promoting behaviour of CAFs, and this phenomenon led to a prominent attenuation of metastatic dissemination in vivo as well. Mechanistically, transcriptome analysis on tumour-promoting CAFs revealed that silver-based nanomaterials trigger expressional changes in genes related to cancer invasion and tumour metastasis. CONCLUSIONS: Here we report that metal nanoparticles can influence the cancer-promoting activity of tumour stroma by affecting the gene expressional and secretory profiles of stromal fibroblasts and thereby altering their intrinsic crosstalk with malignant cells. This potential of metal nanomaterials should be exploited in multimodal treatment approaches and translated into improved therapeutic outcomes.


Assuntos
Antineoplásicos/química , Fibroblastos Associados a Câncer/efeitos dos fármacos , Nanopartículas Metálicas/química , Metástase Neoplásica/tratamento farmacológico , Ligas/química , Animais , Antineoplásicos/uso terapêutico , Fibroblastos Associados a Câncer/patologia , Linhagem Celular Tumoral , Movimento Celular , Sobrevivência Celular , Progressão da Doença , Doxorrubicina/química , Doxorrubicina/uso terapêutico , Feminino , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Ouro/química , Humanos , Nanopartículas Metálicas/uso terapêutico , Camundongos Endogâmicos BALB C , Metástase Neoplásica/patologia , Transplante de Neoplasias , Prata/química , Microambiente Tumoral/efeitos dos fármacos
16.
Transplant Proc ; 51(4): 1286-1288, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31101215

RESUMO

Post-transplant lymphoproliferative disorders are a possible complication of kidney transplant due to chronic immunosuppressive therapy, and they can elevate the mortality rate. Furthermore, the type of clinical appearance has a wide range. We describe a case of a 38-year-old male recipient who developed post-transplant lymphoproliferative disorders and received successful treatment. The recipient had received a kidney with 1 HLA-B and 1 HLA-DR match, and the deceased donor allotransplant was performed successfully on December 9, 2012. The cause of kidney failure was membranoproliferative-glomerulonephritis proved by biopsy results. The induction therapy was antithymocyte globulin; the basic immunosuppressive therapy consisted of tacrolimus, steroid, and mycophenolate mofetil. After 2 months the patient had elevated serum creatinine level, and biopsy results revealed cellular rejection (Banff grade I). We applied steroid bolus therapy. After that the graft worked properly for 5 years, and the patient had no symptoms or complaints; then he had right lower abdomen pain. After urgent procedures (laboratory diagnostics, abdominal ultrasonography, computed tomography), we operated on the patient in a short time, and after a few weeks the fluorescence in situ hybridization confirmed the translocation of region C-myc; the diagnosis was diffuse large B-cell lymphoma. With the assistance of hematologists, the patient received adequate therapy. He was asymptomatic half a year after the rituximab with cyclophosphamide, vincristine, doxorubicin, methotrexate/ifosfamide, etoposide, and high-dose cytarabine protocol therapy; the lymphoma is in remission. Our case is worth presenting because immunosuppressive drugs can modify the clinical picture, complicating the diagnosis and delaying treatment.


Assuntos
Hospedeiro Imunocomprometido , Imunossupressores/efeitos adversos , Transplante de Rim , Linfoma não Hodgkin/imunologia , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Humanos , Terapia de Imunossupressão/efeitos adversos , Transplante de Rim/métodos , Linfoma não Hodgkin/tratamento farmacológico , Masculino
17.
Infect Genet Evol ; 71: 140-150, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30905772

RESUMO

It is increasingly recognized that fundamental differences exist between high-risk and low-risk human papillomavirus (HPV) genotypes regarding interactions with the host. This study aims to join the recently emerging efforts to uncover these differences at the complete genome level and to study how they may influence the disease caused. Sixteen samples of thirteen patients with various HPV6-mediated benign mucosal disorders (nine recurrent respiratory papillomatoses with 2-8 recurrences, one condyloma acuminatum and three premalignant lesions of the genital mucosa) were sampled to determine the complete virus genomes. We collected the 197 HPV6 complete genomes deposited in the GenBank for cluster analysis to determine (sub)lineages. Genome polymorphisms were determined against the reference sequences of the (sub)lineages. Genome polymorphisms of the long control region (LCR) were tested for putative transcription factor binding sites; their functional analysis was performed by transient transfection of cloned whole LCRs into HEp-2 cells using a luciferase reporter system. Genomes from the same patients were always identical. Three, nine and one patients carried HPV6 lineage A, sublineage B1 and B2 variants, respectively. The three lineage A sequences were highly similar to each other, but distinct from the reference genome. A unique non-synonymous single nucleotide polymorphism (SNP) was found in the E5a open reading frame (ORF). Sublineage B1 genomes were more diverse, exhibited unique non-synonymous SNPs in the LCR and the E2/E4, L1, L2 ORFs. LCR activity of lineage A and sublineage B1 differed significantly; activity of one sublineage B1 LCR exhibiting two unique SNPs was significantly higher than that of other B1 LCR variants, close to the mean of LCR activities of lineage A variants. Different HPV6 lineages showed marked differences in variability patterns of the different genome regions. This may be involved in the differences in their distribution in different diseases or patient populations.


Assuntos
Papillomavirus Humano 6/genética , Adulto , Idoso , Criança , Condiloma Acuminado/virologia , Feminino , Variação Genética , Genoma Viral , Genômica , Papillomavirus Humano 6/patogenicidade , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Papillomavirus/virologia , Filogenia , Polimorfismo Genético , Infecções Respiratórias/virologia , Adulto Jovem
18.
J Nanobiotechnology ; 17(1): 9, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30670028

RESUMO

BACKGROUND: Development of multidrug resistance (MDR) is a major burden of successful chemotherapy, therefore, novel approaches to defeat MDR are imperative. Although the remarkable anti-cancer propensity of silver nanoparticles (AgNP) has been demonstrated and their potential application in MDR cancer has been proposed, the nanoparticle size-dependent cellular events directing P-glycoprotein (Pgp) expression and activity in MDR cancer have never been addressed. Hence, in the present study we examined AgNP size-dependent cellular features in multidrug resistant breast cancer cells. RESULTS: In this study we report that 75 nm AgNPs inhibited significantly Pgp efflux activity in drug-resistant breast cancer cells and potentiated the apoptotic effect of doxorubicin, which features were not observed upon 5 nm AgNP treatment. Although both sized AgNPs induced significant ROS production and mitochondrial damage, 5 nm AgNPs were more potent than 75 nm AgNPs in this respect, therefore, these effects can not to be accounted for the reduced transport activity of ATP-driven pumps observed after 75 nm AgNP treatments. Instead we found that 75 nm AgNPs depleted endoplasmic reticulum (ER) calcium stores, caused notable ER stress and decreased plasma membrane positioning of Pgp. CONCLUSION: Our study suggests that AgNPs are potent inhibitors of Pgp function and are promising agents for sensitizing multidrug resistant breast cancers to anticancer drugs. This potency is determined by their size, since 75 nm AgNPs are more efficient than smaller counterparts. This is a highly relevant finding as it renders AgNPs attractive candidates in rational design of therapeutically useful agents for tumor targeting. In the present study we provide evidence that exploitation of ER stress can be a propitious target in defeating multidrug resistance in cancers.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Neoplasias da Mama/tratamento farmacológico , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Nanopartículas Metálicas , Prata , Antineoplásicos/uso terapêutico , Retículo Endoplasmático/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Tamanho da Partícula , Prata/farmacologia
19.
Oncol Rep ; 41(2): 839-852, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30535493

RESUMO

Myofibroblasts (MFs) are present in healthy tissues and are also key components of the tumor microenvironment. In the present study a comparative analysis of MFs obtained from various gastrointestinal tumor tissues and from tumor­adjacent normal tissues of cancer patients was performed, with the aim to evaluate differences in MF morphology, gene expression profile and function. The goal was to correlate the observed morphological and functional variations with the underlying genetic and epigenetic backgrounds. The mutation frequency of MFs was assessed by next generation sequencing. The transcript levels of cancer­specific genes were determined by TaqMan array and quantitative polymerase chain reaction. Epigenetic modifications were analyzed by immunocytochemistry and western blotting. The migratory capacity of MFs was assessed by scratch assay, whereas matrix metalloproteinase expression and activity were obtained by quantitative polymerase chain reaction and zymography. The results of the present study demonstrate that MFs were present in an increased number and with altered morphology in tumor samples compared with the healthy tissue. Although the detected number of mutations in tumor­associated and normal tissue­derived MFs did not differ markedly, shifts in the level of specific acetylated and methylated histone proteins, namely decreased levels of trimethylated H3K9 and acetylated H4K16 were demonstrated in tumor­associated MFs. Transcript levels of several tumor­specific genes involved in metastasis, regulation of cellular growth, apoptosis, as well as in hypoxia­angiogenesis were altered in tumor­derived MF cultures. Increased mRNA levels were obtained and activity of matrix metalloproteases in tumor­derived MFs and these cells also exhibited a higher migratory capacity compared with the normal MFs. In summary, the results of the present study indicate that tumor­associated MFs display an altered phenotype compared with healthy tissue derived counterparts. The results imply that epigenetic rather than genetic alterations are associated with the development of the distinct expressional and functional features, which define this MF phenotype in the tumor microenvironment.


Assuntos
Epigênese Genética , Neoplasias Esofágicas/genética , Genes Neoplásicos/genética , Miofibroblastos/metabolismo , Microambiente Tumoral/genética , Acetilação , Idoso , Apoptose/genética , Proliferação de Células/genética , Metilação de DNA , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Esôfago/patologia , Esôfago/cirurgia , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Histonas/genética , Histonas/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Polimorfismo Genético , RNA Mensageiro/metabolismo
20.
Exp Clin Transplant ; 17(5): 685-687, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30398101

RESUMO

Simultaneous pancreas-kidney transplant is the ultimate therapy for patients who have uncontrolled and complicated type 1 diabetes mellitus with end-stage renal disease. The combined pancreas transplant provides a euglycemic milieu for the kidney and protects it from recurrence of diabetic complications. Our patient, a 41-year-old woman with end-stage diabetic nephropathy and history of multiple abdominal surgeries (ovarian cyst fenestration, adnexal extirpation, abdominal wall reconstruction), including urinary diversion (Bricker loop, above double J stent), underwent simultaneous pancreas-kidney transplant. After reperfusion, the kidney had immediate function and creatinine levels dropped to normal levels during the early postoperative period (creatinine of 102 µmol/L, estimated glomerular filtration rate of 52 mL/min/1.73 m2) and remained stable during follow-up. Serum glucose levels dropped to within normal ranges postoperatively and remained so during follow-up. The postoperative course was complicated by hydronephrosis due to transient edema of the anastomosis of the ureter to the Bricker loop, after early incidental removal of the double J catheter. This was successfully treated with a temporary percutaneous nephrostomy. Multiple previous surgeries, including a Bricker deviation, may not be a definitive contraindication for simultaneous pancreas-kidney transplant. In selected cases, special considerations may lead to a successful procedure providing better quality of life and life expectancy, even for patients with multiple comorbidities.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/cirurgia , Nefropatias Diabéticas/complicações , Nefropatias Diabéticas/cirurgia , Falência Renal Crônica/complicações , Falência Renal Crônica/cirurgia , Transplante de Rim , Transplante de Pâncreas , Derivação Urinária , Adulto , Feminino , Humanos , Derivação Urinária/métodos
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