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1.
Cells ; 13(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38474391

RESUMO

Parenchyma of pulmonary cancers acquires contractile properties that resemble those of muscles but presents some particularities. These non-muscle contractile tissues could be stimulated either electrically or chemically (KCl). They present the Frank-Starling mechanism, the Hill hyperbolic tension-velocity relationship, and the tridimensional time-independent tension-velocity-length relationship. Relaxation could be obtained by the inhibition of crossbridge molecular motors or by a decrease in the intracellular calcium concentration. They differ from muscles in that their kinetics are ultraslow as evidenced by their low shortening velocity and myosin ATPase activity. Contractility is generated by non-muscle myosin type II A and II B. The activation of the ß-catenin/WNT pathway is accompanied by the high level of the non-muscle myosin observed in lung cancers.


Assuntos
Neoplasias Pulmonares , Miosinas , Humanos , Miosinas/metabolismo , Contração Muscular , Músculos/metabolismo
2.
PLoS One ; 19(3): e0298979, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38452149

RESUMO

Thermodynamic consequences of a three-hour long anoxia were investigated on the isolated mammalian rat myocardium. The anoxic heart operated in a far-from-equilibrium manner as attested by the non-linearity between the thermodynamic force and the thermodynamic flow. When subjected to slight fluctuations due to anoxia, the open far-from-equilibrium cardiac system presented a thermodynamic bifurcation at ~ 60 minutes of anoxia. The bifurcation was characterized by a sudden change of direction in the bifurcation diagram of a one-dimensional nonlinear differential equation with one parameter and occurred at a non-hyperbolic fixed point at which moment the heart lost its thermodynamic stability. The parameter of the differential equation was the single force of the myosin molecular motor. These results helped to reflect a self-organized process and the occurrence of a dissipative structure. This offers valuable insights into our understanding of myocardial protection and could be of considerable interest, especially for heart transplants where the recipient must benefit from the donor's heart in the shortest possible time.


Assuntos
Coração , Miocárdio , Ratos , Animais , Hipóxia , Termodinâmica , Mamíferos
3.
Front Cardiovasc Med ; 9: 897657, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386306

RESUMO

Objectives: Although critical in animal and human development and pathology, a measurement of the quantitative expression of 5-HTR serotonin receptors on animal or human valvular tissues has never been performed. Methods: Quantification of the most frequent 5-HTRs reported as being present in human peripheral tissue was performed using radiolabeled agonists/antagonists. A membrane protein extract from normal human valves (aortic/mitral/tricuspid and some pulmonary) and associated diseased left myocardium, all unusable in clinics, were obtained from the Homograft bank. Results: We analyzed 5-HT1AR/5-HT1B/DR/5-HT2AR/5-HT2BR/5-HT 2CR/5-HT4R/5-HT7R from 28 hearts. We confirmed the presence of tissue and measured the quantitative content for respective proteins in femtomol/mg of protein extracts: for 5-HT2AR (35.9+/-0.7), 5-HT2BR (28.8+/-1.3) but also a newly observed and robust expression for 5-HT4R (38+/-4.2). We identified one, 5-HT1ARs (4.9+/-0.3), and the possible expression, but at a very low level, of previously reported 5-HT1B/DRs (1.3+/-0.5) as well as the new 5-HT7Rs (3.5+/0.1) and 5-HT2CRs (1.2+/-0.1). Interestingly, by using univariate analysis, we were able to observe many correlations between the different 5-HTR levels of expression especially between 5-HT1AR/5-HT1B/DR and also between 5-HT4R/5-HT7R, but none were observed between 5-HT2AR and 5-HT2BR. Using multivariate analyses for a specific 5-HTR level of expression, after adjustment for implantation sites and other 5-HTRs, we found that 5-HT1AR was correlated with 5-HT1B/DR;5-HT4R with 5-HT7R and 5-HT1AR;5-HT2BR with 5-HT2AR only. For 5-HT2C, no correlation was observed. Conclusion: 5-HT2AR/5-HT2BR and 5-HT4R were all observed to have a high and equal level of expression on human valves, but that of 5-HT1AR was more limited. Since these non-5-HT2Rs are coupled with different G-proteins, with specific signaling, theoretically they may control the main 5-HT2R signaling (i.e., PLC/DAG-PKC-ERK/Ras/Src signaling) involved in valvular fibrosis and degeneration.

4.
Int J Mol Sci ; 23(13)2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35805967

RESUMO

Contraction of the heart is caused by actin filaments sliding along myosin filaments. This generates a frictional force inducing wear of the contractile apparatus. We postulated that this process could be exacerbated when the heart was submitted to severe anoxia. Anoxia induced dramatic abnormalities in the molecular properties of actin-myosin crossbridges. We applied the formalism of far-from-equilibrium thermodynamics to the left ventricular papillary muscles (LVPMs) of mammalian rat hearts which had been subjected to a prolonged anoxia (3 h). We showed that when subjected to prolonged anoxia, the heart operated far-from-equilibrium as evidenced by the non-linearity between thermodynamic force (F/T: Frictional force/Kelvin temperature) and thermodynamic flow (v0: myofilament sliding velocity). The rate of entropy production (EPR) was the product of (F/T) and v0. The excess entropy production (EEP) was equal to ∂δ2S∂t = ∂FTδvo; (S: entropy). The tribological system remained stable when EEP was positive and became unstable when EEP became negative, thus characterizing instability of the system and reflecting the occurrence of self-organization and possibly dissipative structures. After 3 h anoxia, re-oxygenation induced significant reversibility. About 20% of the myosin heads did not recover despite re-oxygenation. These results may be of importance in the context of heart transplantation where the delay between the time of sampling from the donor and the time of the graft installation in the recipient should be as short as possible.


Assuntos
Hipóxia , Miosinas , Animais , Entropia , Fricção , Mamíferos , Miosinas/química , Ratos , Termodinâmica
5.
Drug Resist Updat ; 63: 100852, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35849943

RESUMO

NSCLC is the leading cause of cancer mortality and represents a major challenge in cancer therapy. Intrinsic and acquired anticancer drug resistance are promoted by hypoxia and HIF-1α. Moreover, chemoresistance is sustained by the activation of key signaling pathways (such as RAS and its well-known downstream targets PI3K/AKT and MAPK) and several mutated oncogenes (including KRAS and EGFR among others). In this review, we highlight how these oncogenic factors are interconnected with cell metabolism (aerobic glycolysis, glutaminolysis and lipid synthesis). Also, we stress the key role of four metabolic enzymes (PFK1, dimeric-PKM2, GLS1 and ACLY), which promote the activation of these oncogenic pathways in a positive feedback loop. These four tenors orchestrating the coordination of metabolism and oncogenic pathways could be key druggable targets for specific inhibition. Since PFK1 appears as the first tenor of this orchestra, its inhibition (and/or that of its main activator PFK2/PFKFB3) could be an efficacious strategy against NSCLC. Citrate is a potent physiologic inhibitor of both PFK1 and PFKFB3, and NSCLC cells seem to maintain a low citrate level to sustain aerobic glycolysis and the PFK1/PI3K/EGFR axis. Awaiting the development of specific non-toxic inhibitors of PFK1 and PFK2/PFKFB3, we propose to test strategies increasing citrate levels in NSCLC tumors to disrupt this interconnection. This could be attempted by evaluating inhibitors of the citrate-consuming enzyme ACLY and/or by direct administration of citrate at high doses. In preclinical models, this "citrate strategy" efficiently inhibits PFK1/PFK2, HIF-1α, and IGFR/PI3K/AKT axes. It also blocks tumor growth in RAS-driven lung cancer models, reversing dedifferentiation, promoting T lymphocytes tumor infiltration, and increasing sensitivity to cytotoxic drugs.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Citratos/uso terapêutico , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , Oncogenes , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/genética
6.
Cancers (Basel) ; 14(4)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35205621

RESUMO

Surgery is the mainstay treatment of non-small-cell lung cancer (NSCLC), but its impact on very-long-term survival (beyond 15 years) has never been evaluated. METHODS: All patients operated on for major lung resection (Jun. 2001-Dec. 2002) for NSCL in the Thoracic Surgery Department at Paris-Hôtel-Dieu-University-Hospital were included. Patients' characteristics were prospectively collected. Vital status was obtained by checking INSEE database and verifying if reported as "non-death" by the hospital administrative database and direct phone interviews with patients of families. RESULTS: 345 patients were included. The 15- and 20-year survival rates were 12.2% and 5.7%, respectively. At univariate analysis, predictors of worse survivals were: increasing age at surgery (p = 0.0042), lower BMI (p = 0.009), weight loss (p = 0.0034), higher CRP (p = 0.049), pathological stage (p = 0.00000042), and, among patients with adenocarcinoma, higher grade (p = 0.028). Increasing age (p = 0.004), cumulative smoking (p = 0.045), lower BMI (0.046) and pathological stage (p = 0.0026), were independent predictors of long-term survival at Cox multivariate analysis. In another model, increasing age (p = 0.013), lower BMI (p = 0.02), chronic bronchitis (p = 0.03), lower FEV1% (p = 0.00019), higher GOLD class of COPD (p = 0.0079), and pathological stage (p = 0.000024), were identified as independent risk factors. CONCLUSIONS: Very-long-term survivals could be achieved after surgery of NSCLC, and factors classically predicting 5- and 10-years survival also determined longer outcomes suggesting that both initial tumor aggressiveness and host's characteristics act beyond the period usually taken into account in oncology.

7.
J Cardiovasc Transl Res ; 15(1): 179-203, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34342855

RESUMO

Cardiac cells interact with the extracellular matrix (ECM) proteins through integrin mechanoreceptors that control many cellular events such as cell survival, apoptosis, differentiation, migration, and proliferation. Integrins play a crucial role in cardiac development as well as in cardiac fibrosis and hypertrophy. Integrins recognize oligopeptides present on ECM proteins and are involved in three main types of interaction, namely with collagen, laminin, and the oligopeptide RGD (Arg-Gly-Asp) present on vitronectin and fibronectin proteins. To date, the specific role of integrins recognizing the RGD has not been addressed. In this review, we examine their role during cardiac development, their role on cardiac cells, and their upregulation during pathological processes such as heart fibrosis and hypertrophy. We also examine their role in regenerative and angiogenic processes after myocardial infarction (MI) in the peri-infarct area. Specific targeting of these integrins may be a way of controlling some of these pathological events and thereby improving medical outcomes.


Assuntos
Integrinas , Infarto do Miocárdio , Adesão Celular , Proteínas da Matriz Extracelular , Coração , Humanos , Hipertrofia , Integrinas/metabolismo , Oligopeptídeos
8.
Int J Mol Sci ; 22(22)2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34830447

RESUMO

Currently, the clinical impact of cell therapy after a myocardial infarction (MI) is limited by low cell engraftment due to low cell retention, cell death in inflammatory and poor angiogenic infarcted areas, secondary migration. Cells interact with their microenvironment through integrin mechanoreceptors that control their survival/apoptosis/differentiation/migration and proliferation. The association of cells with a three-dimensional material may be a way to improve interactions with their integrins, and thus outcomes, especially if preparations are epicardially applied. In this review, we will focus on the rationale for using collagen as a polymer backbone for tissue engineering of a contractile tissue. Contractilities are reported for natural but not synthetic polymers and for naturals only for: collagen/gelatin/decellularized-tissue/fibrin/Matrigel™ and for different material states: hydrogels/gels/solids. To achieve a thick/long-term contractile tissue and for cell transfer, solid porous compliant scaffolds are superior to hydrogels or gels. Classical methods to produce solid scaffolds: electrospinning/freeze-drying/3D-printing/solvent-casting and methods to reinforce and/or maintain scaffold properties by reticulations are reported. We also highlight the possibility of improving integrin interaction between cells and their associated collagen by its functionalizing with the RGD-peptide. Using a contractile patch that can be applied epicardially may be a way of improving ventricular remodeling and limiting secondary cell migration.


Assuntos
Colágeno/uso terapêutico , Infarto do Miocárdio/terapia , Impressão Tridimensional , Engenharia Tecidual , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Diferenciação Celular/efeitos dos fármacos , Colágeno/química , Humanos , Hidrogéis/uso terapêutico , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Peptídeos/genética , Peptídeos/uso terapêutico , Alicerces Teciduais/química
9.
Int J Mol Sci ; 22(14)2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34299379

RESUMO

Myofibroblasts are contractile cells found in multiple tissues. They are physiological cells as in the human placenta and can be obtained from bone marrow mesenchymal stem cells after differentiation by transforming growth factor-ß (TGF-ß). They are also found in the stroma of cancerous tissues and can be located in non-muscle contractile tissues. When stimulated by an electric current or after exposure to KCl, these tissues contract. They relax either by lowering the intracellular Ca2+ concentration (by means of isosorbide dinitrate or sildenafil) or by inhibiting actin-myosin interactions (by means of 2,3-butanedione monoxime or blebbistatin). Their shortening velocity and their developed tension are dramatically low compared to those of muscles. Like sarcomeric and smooth muscles, they obey Frank-Starling's law and exhibit the Hill hyperbolic tension-velocity relationship. The molecular motor of the myofibroblast is the non-muscle myosin type IIA (NMIIA). Its essential characteristic is the extreme slowness of its molecular kinetics. In contrast, NMIIA develops a unitary force similar to that of muscle myosins. From a thermodynamic point of view, non-muscle contractile tissues containing NMIIA operate extremely close to equilibrium in a linear stationary mode.


Assuntos
Contração Muscular/fisiologia , Músculo Liso/metabolismo , Músculo Liso/fisiologia , Miofibroblastos/metabolismo , Miofibroblastos/fisiologia , Miosinas/metabolismo , Miosina não Muscular Tipo IIA/metabolismo , Humanos , Cinética , Termodinâmica
10.
Cell Mol Neurobiol ; 41(3): 403-429, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32405705

RESUMO

Outflow tract abnormalities are the most frequent congenital heart defects. These are due to the absence or dysfunction of the two main cell types, i.e., neural crest cells and secondary heart field cells that migrate in opposite directions at the same stage of development. These cells directly govern aortic arch patterning and development, ascending aorta dilatation, semi-valvular and coronary artery development, aortopulmonary septation abnormalities, persistence of the ductus arteriosus, trunk and proximal pulmonary arteries, sub-valvular conal ventricular septal/rotational defects, and non-compaction of the left ventricle. In some cases, depending on the functional defects of these cells, additional malformations are found in the expected spatial migratory area of the cells, namely in the pharyngeal arch derivatives and cervico-facial structures. Associated non-cardiovascular anomalies are often underestimated, since the multipotency and functional alteration of these cells can result in the modification of multiple neural, epidermal, and cervical structures at different levels. In most cases, patients do not display the full phenotype of abnormalities, but congenital cardiac defects involving the ventricular outflow tract, ascending aorta, aortic arch and supra-aortic trunks should be considered as markers for possible impaired function of these cells. Neural crest cells should not be considered as a unique cell population but on the basis of their cervical rhombomere origins R3-R5 or R6-R7-R8 and specific migration patterns: R3-R4 towards arch II, R5-R6 arch III and R7-R8 arch IV and VI. A better understanding of their development may lead to the discovery of unknown associated abnormalities, thereby enabling potential improvements to be made to the therapeutic approach.


Assuntos
Vasos Sanguíneos/anormalidades , Movimento Celular , Miocárdio/citologia , Crista Neural/citologia , Animais , Padronização Corporal/genética , Movimento Celular/genética , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo
11.
J Am Heart Assoc ; 9(15): e015909, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32698708

RESUMO

Background Pigs/bovines share common antigens with humans: α-Gal, present in all pigs/bovines close to the human B-antigen; and AH-histo-blood-group antigen, identical to human AH-antigen and present only in some animals. We investigate the possible impact of patients' ABO blood group on bioprosthesis structural valve degeneration (SVD) through calcification/pannus/tears/perforations for patients ≤60 years at implantation. Methods and Results This was a single-center study (Paris, France) that included all degenerative bioprostheses explanted between 1985 and 1998, mostly porcine bioprostheses (Carpentier-Edwards second/third porcine bioprostheses) and some bovine bioprostheses. For the period 1998 to 2014, only porcine bioprostheses with longevity ≥13 years were included (total follow-up ≥29 years). Except for blood groups, important predictive factors for SVD were prospectively collected (age at implantation/longevity/number/site/sex/SVD types) and analyzed using logistic regression. All variables were available for 500 explanted porcine bioprostheses. By multivariate analyses, the A group was associated with an increased risk of: tears (odds ratio[OR], 1.61; P=0.026); pannus (OR, 1.5; P=0.054), pannus with tears (OR, 1.73; P=0.037), and tendency for lower risk of: calcifications (OR, 0.63; P=0.087) or isolated calcification (OR, 0.67; P=0.17). A-antigen was associated with lower risk of perforations (OR 0.56; P=0.087). B-group patients had an increased risk of: perforations (OR, 1.73; P=0.043); having a pannus that was calcified (OR, 3.0, P=0.025). B-antigen was associated with a propensity for calcifications in general (OR, 1.34; P=0.25). Conclusions Patient's ABO blood group is associated with specific SVD types. We hypothesize that carbohydrate antigens, which may or may not be common to patient and animal bioprosthetic tissue, will determine a patient's specific immunoreactivity with respect to xenograft tissue and thus bioprosthesis outcome in terms of SVD.


Assuntos
Bioprótese/efeitos adversos , Próteses Valvulares Cardíacas/efeitos adversos , Sistema ABO de Grupos Sanguíneos , Adolescente , Adulto , Calcinose/etiologia , Criança , Feminino , Doenças das Valvas Cardíacas/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Falha de Prótese , Fatores de Risco , Adulto Jovem
12.
Curr Hypertens Rep ; 22(7): 50, 2020 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-32661611

RESUMO

PURPOSE OF REVIEW: Blood pressure (BP) follows a circadian rhythm (CR) in normotensive subjects. BP increases in the morning and decreases at night. This review aims at providing an up-to-date overview regarding the molecular mechanisms underlying the circadian regulation of BP. RECENT FINDINGS: The suprachiasmatic nucleus (SCN) is the regulatory center for CRs. In SCN astrocytes, the phosphorylated glycogen synthase kinase-3ß (pGSK-3ß) also follows a CR and its expression reaches a maximum in the morning and decreases at night. pGSK-3ß induces the ß-catenin migration to the nucleus. During the daytime, the nuclear ß-catenin increases the expression of the glutamate excitatory amino acid transporter 2 (EAAT2) and glutamine synthetase (GS). In SCN, EAAT2 removes glutamate from the synaptic cleft of glutamatergic neurons and transfers it to the astrocyte cytoplasm where GS converts glutamate into glutamine. Thus, glutamate decreases in the synaptic cleft. This decreases the stimulation of the glutamate receptors AMPA-R and NMDA-R located on glutamatergic post-synaptic neurons. Consequently, activation of NTS is decreased and BP increases. The opposite occurs at night. Despite several studies resulting from animal studies, the circadian regulation of BP appears largely controlled in normotensive subjects by the canonical WNT/ß-catenin pathway involving the SCN, astrocytes, and glutamatergic neurons.


Assuntos
Ritmo Circadiano , Hipertensão , Animais , Pressão Sanguínea , Ácido Glutâmico , Humanos , Núcleo Supraquiasmático
13.
Cells ; 9(6)2020 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-32575851

RESUMO

Mesenchymal stromal cells (MSCs) were obtained from human bone marrow and amplified in cultures supplemented with human platelet lysate. Once semi-confluent, cells were seeded in solid collagen scaffolds that were rapidly colonized by the cells generating a 3D cell scaffold. Here, they acquired a myofibroblast phenotype and when exposed to appropriate chemical stimulus, developed tension and cell shortening, similar to those of striated and smooth muscle cells. Myofibroblasts contained a molecular motor-the non-muscle myosin type IIA (NMMIIA) whose crossbridge (CB) kinetics are dramatically slow compared with striated and smooth muscle myosins. Huxley's equations were used to determine the molecular mechanical properties of NMMIIA. Thank to the great number of NMMIIA molecules, we determined the statistical mechanics (SM) of MSCs, using the grand canonical ensemble which made it possible to calculate various thermodynamic entities such as the chemical affinity, statistical entropy, internal energy, thermodynamic flow, thermodynamic force, and entropy production rate. The linear relationship observed between the thermodynamic force and the thermodynamic flow allowed to establish that MSC-laden in collagen scaffolds were in a near-equilibrium stationary state (affinity ≪ RT), MSCs were also seeded in solid collagen scaffolds functionalized with the tripeptide Arg-Gly-Asp (RGD). This induced major changes in NMMIIA SM particularly by increasing the rate of entropy production. In conclusion, collagen scaffolds laden with MSCs can be viewed as a non-muscle contractile bioengineered tissue operating in a near-equilibrium linear regime, whose SM could be substantially modified by the RGD peptide.


Assuntos
Colágeno/metabolismo , Células-Tronco Mesenquimais/metabolismo , Miosina não Muscular Tipo IIA/metabolismo , Alicerces Teciduais/química , Diferenciação Celular , Humanos , Oligopeptídeos , Termodinâmica
14.
Cancers (Basel) ; 12(2)2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31979060

RESUMO

Lower pre-surgery Body Mass Index (BMI) and low muscle mass impact negatively long-term survival of non-small cell lung cancer (NSCLC). We investigated their influence on survival after major lung resection for NSCLC. METHODS: A retrospective analysis of a prospectively collected database was made on 304 consecutive patients. RESULTS: Underweight, normal, overweight and obese patients represented 7.6%, 51.6%, 28.6%, and 12.6% of the pre-disease population. Weight loss and gain were recorded in 5% and 44.4% of patients, respectively. Low muscle mass was more frequently associated with BMI < 25 kg/m2 (p < 0.000001). Overall survival was positively affected by pre-disease (p = 0.036) and pre-surgery (p = 0.017) BMI > 25 kg/m2, and, even more, in case of BMI > 25 kg/m2 and increasing weight (p = 0.012). Long-term outcome was negatively influenced by low muscle mass (p = 0.042) and weight loss (p = 0.0052) as well as age (p = 0.017), ASA categories (p = 0.025), extent of resection (p = 0.0001), pleural invasion (p = 0.0012) and higher pathologic stage (p < 0.0001). Three stepwise multivariable models confirmed the independent favorable prognostic value of higher pre-disease (RR 0.66[0.49-0.89], p = 0.006) and pre-surgery BMI (RR 0.72[0.54-0.98], p = 0.034), and the absence of low muscle mass (RR 0.56[0.37-0.87], p = 0.0091). CONCLUSIONS: Body reserves assessed by simple clinical markers impact survival of surgically treated NSCLC. Strategies improving body fat and muscular mass before surgery should be considered.

15.
Front Oncol ; 9: 1248, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31803621

RESUMO

Canonical WNT/ß-catenin signaling is involved in most of the mechanisms that lead to the formation and development of cancer cells. It plays a central role in three cyclic processes, which are the cell division cycle, the immune cycle, and circadian rhythms. When the canonical WNT pathway is upregulated as in cancers, the increase in ß-catenin in the nucleus leads to activation of the expression of numerous genes, in particular CYCLIN D1 and cMYC, where the former influences the G1 phase of the cell division cycle, and the latter, the S phase. Every stage of the immune cycle is disrupted by the canonical WNT signaling. In numerous cancers, the dysfunction of the canonical WNT pathway is accompanied by alterations of the circadian genes (CLOCK, BMAL1, PER). Induction of these cyclic phenomena leads to the genesis of thermodynamic mechanisms that operate far from equilibrium, and that have been called "dissipative structures." Moreover, upregulation of the canonical WNT/ß-catenin signaling is important in the myofibroblasts of the cancer stroma. Their differentiation is controlled by the canonical WNT /TGF-ß1 signaling. Myofibroblasts present ultraslow contractile properties due to the presence of the non-muscle myosin IIA. Myofibroblats also play a role in the inflammatory processes, often found in cancers and fibrosis processes. Finally, upregulated canonical WNT deviates mitochondrial oxidative phosphorylation toward the Warburg glycolysis metabolism, which is characteristic of cancers. Among all these cancer-generating mechanisms, the upregulated canonical WNT pathway would appear to offer the best hope as a therapeutic target, particularly in the field of immunotherapy.

16.
PLoS One ; 14(10): e0222683, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31574082

RESUMO

Mesenchymal stem cells (MSCs) were obtained from human bone marrow and amplified in cultures supplemented with human platelet lysate in order to generate myofibroblasts. When MSCs were seeded in solid collagen scaffolds, they differentiated into myofibroblasts that were observed to strongly bind to the substrate, forming a 3D cell scaffold network that developed tension and shortening after KCl stimulation. Moreover, MSC-laden scaffolds recapitulated the Frank-Starling mechanism so that active tension increased in response to increases in the initial length of the contractile system. This constituted a bioengineering tissue that exhibited the contractile properties observed in both striated and smooth muscles. By using the A. F. Huxley formalism, we determined the myosin crossbridge (CB) kinetics of attachment (f1) and detachment (g1 and g2), maximum myosin ATPase activity, molar myosin concentration, unitary CB force and maximum CB efficiency. CB kinetics were dramatically slow, characterizing the non-muscle myosin type IIA (NMMIIA) present in myofibroblasts. When MSCs were seeded in solid collagen scaffolds functionalized with Arg-Gly-Asp (RGD), contractility increased and CB kinetics were modified, whereas the unitary NMMIIA-CB force and maximum CB efficiency did not change. In conclusion, we provided a non-muscle bioengineering tissue whose molecular mechanical characteristics of NMMIIA were very close to those of a non-muscle contractile tissue such as the human placenta.


Assuntos
Músculo Liso/metabolismo , Cadeias Pesadas de Miosina/química , Oligopeptídeos/metabolismo , Peptídeos/metabolismo , Plaquetas/metabolismo , Células da Medula Óssea/metabolismo , Diferenciação Celular/genética , Colágeno/química , Colágeno/metabolismo , Humanos , Cinética , Células-Tronco Mesenquimais/metabolismo , Contração Muscular/genética , Miofibroblastos/metabolismo , Cadeias Pesadas de Miosina/genética , Miosinas/química , Miosinas/metabolismo , Oligopeptídeos/química , Peptídeos/química , Cloreto de Potássio/farmacologia
17.
Stem Cells Int ; 2018: 6134787, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29853916

RESUMO

Mesenchymal stromal stem cells (MSC) that reside in the bone marrow (BM) can be amplified in vitro. In 2-dimension (D) cultures, MSC exhibit a morphology similar to fibroblasts, are able to inhibit T lymphocyte and natural killer cell proliferation, and can be differentiated into adipocytes, chondrocytes, or osteoblasts if exposed to specific media. Here we show that medullar MSC cultured in 2D formed an adherent stroma of cells expressing well-organized microfilaments containing α-smooth muscle actin and nonmuscle myosin heavy chain IIA. MSC could be grown in 3D in collagen membranes generating a structure which, upon exposition to 50 mM KCl or to an alternating electric current, developed a contractile strength that averaged 34 and 45 µN/mm2, respectively. Such mechanical tension was similar in intensity and in duration to that of human placenta and was annihilated by isosorbide dinitrate or 2,3-butanedione monoxime. Membranes devoid of MSC did not exhibit a significant contractility. Moreover, MSC nested in collagen membranes were able to control T lymphocyte proliferation, and differentiated into adipocytes, chondrocytes, or osteoblasts. Our observations show that BM-derived MSC cultured in collagen membranes spontaneously differentiate into contractile myofibroblasts exhibiting unexpected properties in terms of cell differentiation potential and of immunomodulatory function.

18.
Ann Emerg Med ; 65(1): 23-6, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24530109

RESUMO

Survival after cardiac arrest depends on prompt and effective cardiopulmonary resuscitation (CPR). Resuscitative teams are more frequently using mechanical chest compression devices, as documented in physiologic and experimental data, suggesting that these devices are more effective than manual CPR. A 41-year-old male patient presented with an ST-elevation myocardial infarction with cardiac arrest. The patient was immediately resuscitated by manual chest compressions; CPR was continued with a mechanical chest compression device (LUCAS 2). The patient had experienced a 15-minute period of "low-flow" without "no-flow" episode. After a discussion with the heart team, we decided that the patient was a candidate for extracorporeal membrane oxygenation (ECMO) therapy. During the ECMO implantation, we noticed that while performing transesophageal echocardiography, chest compressions were ineffective with the machine. After the ECMO implantation, we observed myocardial damage in the right-sided heart cavities. The present case report illustrates the likelihood that the mechanical chest compression device has limitations that might contribute to inadequate CPR. Therefore, rescuers should consider the efficacy of their chest compression through a continuous hemodynamic monitoring during CPR.


Assuntos
Reanimação Cardiopulmonar/instrumentação , Massagem Cardíaca/instrumentação , Parada Cardíaca Extra-Hospitalar/terapia , Adulto , Reanimação Cardiopulmonar/métodos , Ecocardiografia , Oxigenação por Membrana Extracorpórea , Massagem Cardíaca/métodos , Humanos , Masculino , Parada Cardíaca Extra-Hospitalar/diagnóstico por imagem , Falha de Tratamento
19.
PLoS One ; 9(9): e106914, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25238252

RESUMO

BACKGROUND: Hypothesizing that nutritional status, systemic inflammation and tumoral immune microenvironment play a role as determinants of lung cancer evolution, the purpose of this study was to assess their respective impact on long-term survival in resected non-small cell lung cancers (NSCLC). METHODS AND FINDINGS: Clinical, pathological and laboratory data of 303 patients surgically treated for NSCLC were retrospectively analyzed. C-reactive protein (CRP) and prealbumin levels were recorded, and tumoral infiltration by CD8+ lymphocytes and mature dendritic cells was assessed. We observed that factors related to nutritional status, systemic inflammation and tumoral immune microenvironment were correlated; significant correlations were also found between these factors and other relevant clinical-pathological parameters. With respect to outcome, at univariate analysis we found statistically significant associations between survival and the following variables: Karnofsky index, American Society of Anesthesiologists (ASA) class, CRP levels, prealbumin concentrations, extent of resection, pathologic stage, pT and pN parameters, presence of vascular emboli, and tumoral infiltration by either CD8+ lymphocytes or mature dendritic cells and, among adenocarcinoma type, tumor grade (all p<0.05). In multivariate analysis, prealbumin levels (Relative Risk (RR): 0.34 [0.16-0.73], p = 0.0056), CD8+ cell count in tumor tissue (RR = 0.37 [0.16-0.83], p = 0.0162), and disease stage (RR 1.73 [1.03-2.89]; 2.99[1.07-8.37], p = 0.0374- stage I vs II vs III-IV) were independent prognostic markers. When taken together, parameters related to systemic inflammation, nutrition and tumoral immune microenvironment allowed robust prognostic discrimination; indeed patients with undetectable CRP, high (>285 mg/L) prealbumin levels and high (>96/mm2) CD8+ cell count had a 5-year survival rate of 80% [60.9-91.1] as compared to 18% [7.9-35.6] in patients with an opposite pattern of values. When stages I-II were considered alone, the prognostic significance of these factors was even more pronounced. CONCLUSIONS: Our data show that nutrition, systemic inflammation and tumoral immune contexture are prognostic determinants that, taken together, may predict outcome.


Assuntos
Proteína C-Reativa/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Estado Nutricional , Pré-Albumina/metabolismo , Microambiente Tumoral , Linfócitos T CD8-Positivos/imunologia , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Avaliação de Estado de Karnofsky , Análise Multivariada , Gradação de Tumores , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida
20.
Ann Thorac Surg ; 95(4): 1204-10, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23415237

RESUMO

BACKGROUND: The incidence of vascular and lymphatic emboli in a specimen of resected non-small cell lung cancer is variable according to different authors' experience as well as prognostic significance in patients treated by surgery. We aimed at evaluating these factors in an unselected population of patients with primary pulmonary adenocarcinoma treated by major surgical resection. METHODS: Clinical and pathology records of all patients treated by lobectomy or pneumonectomy and nodal dissection for pulmonary adenocarcinoma between June 2001 and June 2006 were retrospectively reviewed. Impact on survival of age, sex, tobacco use, history of chronic obstructive pulmonary disease, extent of resection, pathologic stage, and presence of vascular and lymphatic emboli was studied by univariate analysis and multivariate analysis (for factors significantly associated with survival at univariate analysis). RESULTS: Five hundred three patients underwent lobectomy or pneumonectomy with nodal dissection for pathologically proven lung adenocarcinoma. There were 355 men and 148 women; mean age was 61.1 years, and 181 patients were 65 years old or older; 87% were current or former smokers; 90.3% had pulmonary lobectomy; and 9.7% had pneumonectomy. Pathologic stages were I, II, and III/IV in 45%, 17.9%, and 37.1%, respectively. Vascular emboli and lymphatic emboli were found in 183 of 503 patients (36.4%) and 149 of 503 (29.6%), respectively. Overall 5-year survival for the whole population was 50.7%. At univariate analysis, age more than 65 years (p=0.0019), chronic obstructive pulmonary disease (p=0.042), extent of resection (p=0.047), pathologic stage (p<0.0000001), T size (p=0.0020), T and N variables (p=0.0000016 and p<0.0000001, respectively), presence of vascular emboli (p=0.026), and presence of lymphatic emboli (p=0.000021) were associated with worse prognosis. At multivariate analysis, age more than 65 years (p=0.0047, relative risk 1.5), stage I versus II versus III versus IV (p=0.00000032), and presence of lymphatic emboli (p=0.05, relative risk 1.34) were identified as independent negative prognostic factors. CONCLUSIONS: In an unselected population of patients with pulmonary adenocarcinoma treated by lobectomy or pneumonectomy, the presence of lymphatic emboli is an independent negative prognostic factor.


Assuntos
Adenocarcinoma/cirurgia , Vasos Sanguíneos , Embolia/mortalidade , Neoplasias Pulmonares/cirurgia , Vasos Linfáticos , Células Neoplásicas Circulantes , Pneumonectomia , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Idoso , Embolia/etiologia , Feminino , França/epidemiologia , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Taxa de Sobrevida/tendências
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