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1.
Thromb Res ; 222: 117-123, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36640567

RESUMO

BACKGROUND AND PURPOSE: High-on-treatment platelet reactivity (HTPR) has been established as a predictor of major adverse cardiovascular events (MACE) in patients undergoing percutaneous coronary interventions on dual antiplatelet therapy (DAPT), but no data are available on its predictive value in patients on DAPT after carotid artery stenting (CAS). We aimed to evaluate the possible association between HTPR in patients on aspirin plus clopidogrel therapy after CAS and subsequent MACE. METHODS: All consecutive patients treated with CAS in a single institution were enrolled in a prospective clinical study. HTPR was evaluated with 5 different laboratory assays carried out just before CAS. MACE incidence (cerebral ischemia, myocardial infarction, stent thrombosis, acute limb ischemia and vascular death) was evaluated at 30 days and thereafter at yearly visits. RESULTS: A total of 300 patients were enrolled in the study, and eight were then excluded because blood samples resulted unsuitable for the laboratory testing or CAS aborted for technical problems. Median follow-up was 5.8 years and during this period 47 MACE occurred. HTPR detected by multiplate electronic aggregometry (MEA) and the VASP phosphorylation assay (VASP) were associated with a significantly enhanced risk of MACE (p = 0.048 and p = 0.038, respectively). However, HTPR to three tests (HTPR3) was more strongly predictive of increased risk of a vascular event at follow up (p = 0.005) at bivariate analysis and also at Cox regression multivariate analysis (p = 0.002). CONCLUSIONS: HTPR to three different assays (mainly to VASP + PFA P2Y+ VerifyNow) in patients on DAPT after CAS has predictive value for subsequent MACE. Prospective studies to assess whether platelet function testing-guided antiplatelet therapy is superior to standard DAPT in patient undergoing CAS should be considered.


Assuntos
Estenose das Carótidas , Intervenção Coronária Percutânea , Humanos , Inibidores da Agregação Plaquetária/efeitos adversos , Estudos Prospectivos , Ticlopidina/uso terapêutico , Aspirina , Estenose das Carótidas/cirurgia , Stents/efeitos adversos , Plaquetas , Testes de Função Plaquetária/métodos , Intervenção Coronária Percutânea/métodos , Artérias Carótidas , Resultado do Tratamento
2.
Eur J Vasc Endovasc Surg ; 54(1): 95-103, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28495214

RESUMO

OBJECTIVE/BACKGROUND: Absence of an adequate iliac seal rarely represents an absolute contraindication to endovascular abdominal aortic aneurysm repair. Iliac branch devices (IBD) are increasingly used in patients with extensive aorto-iliac aneurysmal disease, but few data are available on the long-term results of these procedures. METHODS: Between 2006 and 2016, 157 consecutive IBD procedures performed at a single centre were entered into a prospective database. Indications included unilateral or bilateral common iliac artery aneurysms combined or not with abdominal aortic aneurysms. Long-term results were reported according to the Kaplan-Meier method. RESULTS: During the study period 149 patients were treated with an iliac branched endograft. Isolated IBD was implanted in 17.8% of the cases; technical success rate was 97.5%. Peri-operative procedure failure occurred in seven patients, four during surgery and three within 30 days of the procedure. Presence of ipsilateral hypogastric aneurysm (p = .031; Exp [B] = 6.72) and intervention performed during the initial study period (p = .006; Exp [B] = 10.40) were predictive of early failure on multivariate analysis. After a mean follow-up of 44.2 months actuarial freedom from IBD related re-intervention was 97.4%, 95.6%, 94.0%, and 91.8% at 1, 3, 5, and 9 years, respectively. Hypogastric artery patency was 94.7%, 92.6%, and 90.4% at 1, 3, and 10 years, respectively. Presence of a hypogastric aneurysm was an independent predictor of target artery occlusion during follow-up on multivariate analysis (p = .007; Exp [B] = 5.93). CONCLUSION: Iliac branched endografting can now be performed with a high technical success rate; long-term freedom from re-intervention is comparable with patients treated with standard aortic endografting. IBD should be considered a first-option treatment in patients with adequate vascular anatomy unsuitable for standard endovascular aortic repair.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Procedimentos Endovasculares/instrumentação , Aneurisma Ilíaco/cirurgia , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Implante de Prótese Vascular/efeitos adversos , Distribuição de Qui-Quadrado , Bases de Dados Factuais , Intervalo Livre de Doença , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Aneurisma Ilíaco/diagnóstico por imagem , Itália , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Análise Multivariada , Complicações Pós-Operatórias/etiologia , Desenho de Prótese , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
4.
Eur J Vasc Endovasc Surg ; 47(3): 296-303, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24447528

RESUMO

OBJECTIVE: Current data supporting the effect of anticoagulation drug use on aneurysm sealing and the durability of endovascular abdominal aneurysm repair (EVAR) are conflicting. This study assessed the safety of chronic anticoagulation therapy after EVAR. METHODS: Records of 1409 consecutive patients having elective EVAR during 1997-2011 who were prospectively followed were reviewed. Survival, reintervention, conversion, and endoleak rates were analyzed in patients with and without chronic anticoagulants. Cox proportional hazards models were used to estimate the effect of anticoagulation therapy on outcomes. RESULTS: One-hundred and three (7.3%) patients were on chronic anticoagulation drugs (80 on vitamin K antagonists) at the time of EVAR. An additional 46 patients started on anticoagulants after repair were identified. Patients on chronic anticoagulation therapy at repair (mean age 73.6 years; 91 males) had more frequent cardiac disease (74.8% vs. 44.2%; p < 00001), but no other differences in demographic and major baseline comorbidities with respect to the others. At baseline, mean abdominal aortic aneurysm (AAA) diameter was 56.43 mm vs. 54.65 mm (p = .076) and aortic neck length 26.54 mm vs. 25.21 mm (p = .26) in patients with and without anticoagulants, respectively. At 5 years, freedom from endoleak rates were 55.5% vs. 69.9% (p < .0001), and freedom from reintervention/conversion rates were 69.4% vs. 82.4% (p < .0001) in patients with (including those with delayed drug use) and without chronic anticoagulants, respectively. Controlling for covariates with the Cox regression method, at a mean follow-up of 64.3 ± 45.2 months after EVAR, use of anticoagulation drugs was independently associated with an increased risk of endoleak (odds ratio, OR 1.6; 95% confidence interval, CI: 1.23-2.07; p < .0001) and reintervention or late conversion rates (OR 1.8; 95% CI: 1.31-2.48; p < .0001). CONCLUSIONS: The safety of anticoagulation therapy after EVAR is debatable. Chronic anticoagulation drug use risks exposure to a poor long-term outcome. A critical and balanced decision-making approach should be applied to patients with AAA and cardiac disease who may require prolonged anticoagulation treatment.


Assuntos
Anticoagulantes/efeitos adversos , Aneurisma da Aorta Abdominal/cirurgia , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/mortalidade , Endoleak/epidemiologia , Procedimentos Endovasculares , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Complicações Pós-Operatórias/epidemiologia , Período Pós-Operatório , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Varfarina/efeitos adversos
5.
Eur J Vasc Endovasc Surg ; 46(2): 192-200, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23791038

RESUMO

BACKGROUND: Regression of the aneurysmal sac after endovascular repair of abdominal aortic aneurysm (AAA) is an accepted indicator of aneurysm exclusion. This study evaluated the spontaneous decrease in sac diameter over a 10-year period in patients undergoing endovascular aneurysm repair (EVAR) with different stentgrafts. METHODS: 1,450 patients (mean age 73.1 ± 7.7 years; 1,325 male) undergoing EVAR and with a minimum of 1-year computed tomography (CT) imaging were included. Different implanted stentgrafts (n = 622 [42.9%] Zenith, n = 236 [16.3%] AneuRx, n = 179 [12.3%] Talent, n = 83 [5.7%] Endurant, n = 236 [16.3%] Excluder, n = 36 [2.5%] Fortron, 53 [3.7%] Anaconda, n = 5 [0.3%] others) were employed. "Persisting shrinkage" was measured as ≥ 5 mm AAA diameter regression spontaneously persisting or increasing until the end of follow-up without reintervention. Persisting shrinkage among devices was compared with survival and Cox regression analyses. RESULTS: During a median follow-up of 45 months (interquartile range, IQR, 21-79) persisting shrinkage was detected in 768 (53%) aneurysms. Kaplan-Meier estimates of persisting shrinkage were 25.8% at 1 year, 63% at 3 years and 72.6% at 10 years. Persisting shrinkage rates were significantly higher for Zenith (p < .0001), Endurant (p = .013) and new generation Excluder (p < .0001) devices. Cox analyses confirmed that persisting shrinkage rates were independently associated with Zenith (OR 1.33; 95% CI: 1.176-1.514) and Endurant (OR 1.52; 95% CI: 1.108-2.092) stentgrafts and negatively associated with the AneuRx (OR 0.57; 95% CI: 0.477-0.688) device. Survival rates were higher in the persisting shrinkage group: 84.1% vs. 77.8% at 3 years, and 53% vs. 38.1% at 10 years (p < .0001). Freedom from AAA-related-death rate was 100% at 3 years and 99.7% at 10 years in the persisting shrinkage group. CONCLUSIONS: Aneurysm diameter shrinkage can be achieved in most current EVARs with persisting effect at 10 years from repair and indicates the benefit and safety of treatment. Last generation devices seem to be important factors in inducing aneurysm sac shrinkage with similar clinically relevant effects among single models.


Assuntos
Aneurisma Aórtico/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Procedimentos Endovasculares/instrumentação , Desenho de Prótese , Stents , Idoso , Idoso de 80 Anos ou mais , Aneurisma Aórtico/diagnóstico por imagem , Aneurisma Aórtico/mortalidade , Aortografia/métodos , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/mortalidade , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/mortalidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Razão de Chances , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento
6.
J Cardiovasc Surg (Torino) ; 54(1 Suppl 1): 141-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23443599

RESUMO

Although currently there is a trend of using percutaneous transluminal angioplasty (PTA) and stenting for the treatment of long occlusions of superficial femoral artery, many studies reported comparable results in terms of mid- and long-term patency between PTA and stenting and plaque debulking techniques such as remote endarterectomy, directional atherectomy catheter atherectomy and laser guided atherectomy. A successful debulking procedure is strongly associated with patients comorbidities, length of lesions and clinical presentation. In the last decade many new devices have been proposed to improve debulking results. Despite encouraging data about technical feasibility and limb salvage rate, debulking is still associated with a low rate of long-term primary and secondary patency. However, randomized clinical trials are expected and can hopefully provide conclusions on the effective durability of these procedures.


Assuntos
Aterectomia/métodos , Artéria Femoral/cirurgia , Doença Arterial Periférica/cirurgia , Placa Aterosclerótica , Artéria Poplítea/cirurgia , Idoso , Idoso de 80 Anos ou mais , Aterectomia/efeitos adversos , Aterectomia/instrumentação , Comorbidade , Constrição Patológica , Desenho de Equipamento , Feminino , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/patologia , Artéria Femoral/fisiopatologia , Humanos , Estimativa de Kaplan-Meier , Salvamento de Membro , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/patologia , Doença Arterial Periférica/fisiopatologia , Artéria Poplítea/diagnóstico por imagem , Artéria Poplítea/patologia , Artéria Poplítea/fisiopatologia , Fatores de Risco , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Grau de Desobstrução Vascular
7.
Eur J Vasc Endovasc Surg ; 44(3): 252-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22819739

RESUMO

BACKGROUND: Invasive management of patients ≥80 years of age with carotid stenosis may be questionable. The higher likelihood of stroke needs to be balanced with the increased perioperative risk and the reduced life expectancy of this ageing population. The purpose of this study was to evaluate the clinical relevance of carotid stenosis revascularisation in octogenarians. METHODS: All patients ≥80 years of age who received carotid revascularisation in 2001-2010 were reviewed for perioperative and 5-year outcomes. The experience was comprehensive of carotid endarterectomy (CEA) and carotid stenting (CAS) performed during the training frame when age was not a contraindication for this procedure. Mortality rates were compared to those of octogenarians of the same geographical territory according to all-cause and stroke-related mortality national statistics datasets. RESULTS: A total of 348 procedures performed in ≥80-year-old patients (272 males) were reviewed: 162 (46.6%) were by CAS and 169 (48.6%) were for symptomatic disease. Perioperative stroke/death rate was 5.5% and was non-significantly higher for symptomatic disease (7.1% vs. 3.9% asymptomatic; p = 0.24), after CAS (6.2% vs. 4.8% CEA; p = 0.64) and in females (6.6% vs. 5.1% males; p = 0.57). At median follow-up of 36.18 months, 95 deaths and 21 new ischaemic strokes (12 fatal) occurred with 5-year Kaplan-Meier freedom from stroke of 84.8% (78.7%, symptomatic vs. 90.3% asymptomatic; p = 0.003). According to national datasets, in 80-85-year-old resident population 5-year mortality was 29.9% (23.4% females, 40.6% males) and ischaemic stroke-related mortality was 14.9% (16.8% females, 13.0% males). Corresponding figures from treated population showed a 5-year mortality of 49.4%, higher in males (39.5% females, 52.5% males) and ischaemic stroke-related mortality of 20.2%, higher in females (40.0% females, 15.6% males). Comparing data from the study population with residents' figures, ischaemic stroke-related mortality hazard was significantly higher in the study females: odds ratio (OR) 3.2, 95% confidence interval (CI) 1.16-9.17; p = 0.029 (for males: OR 0.97, 95%CI 0.89-1.10; p = 0.99). CONCLUSIONS: Despite perioperative stroke/death risks being lower compared with CAS, the benefit of surgical carotid revascularisation in old patients remains controversial due to limited life expectancy and high fatality of stroke in this ageing population. Invasive treatment of carotid stenosis may not be warranted in most patients ≥80 years of age with carotid stenosis, especially when female and asymptomatic.


Assuntos
Angioplastia , Estenose das Carótidas/terapia , Endarterectomia das Carótidas , Acidente Vascular Cerebral/prevenção & controle , Fatores Etários , Idoso de 80 Anos ou mais , Angioplastia/efeitos adversos , Angioplastia/instrumentação , Angioplastia/mortalidade , Estenose das Carótidas/complicações , Estenose das Carótidas/mortalidade , Estenose das Carótidas/cirurgia , Endarterectomia das Carótidas/efeitos adversos , Endarterectomia das Carótidas/mortalidade , Feminino , Humanos , Itália , Estimativa de Kaplan-Meier , Masculino , Razão de Chances , Seleção de Pacientes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Stents , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/mortalidade , Fatores de Tempo , Resultado do Tratamento
8.
J Cardiovasc Surg (Torino) ; 53(1 Suppl 1): 179-88, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22433737

RESUMO

Even though differences between first-bypass vs. first-endovascular approach in below the knee (BTK) lesions have never been adequately compared, endovascular strategy first approach can be currently successfully used to treat BTK lesions in patients with critical limb ischemia (CLI). Success however is strongly associated with risk groups, severity of disease and degree of clinical presentation beside the method of revascularization. From available data, the best results of endovascular first approach for BTK lesions can be achieved with multivessel and tibial (more than peroneal alone) recanalization and Rutherford 4 or 5 ischemia changes, especially if the correct angiosome can be revascularized (direct flow to the feeding artery of the foot) and there is no renal failure. For patients in Rutherford class 6 and extensive gangrene/tissue loss, BTK endovascular strategy alone does not seem to provide ideal results. Outcomes of interventional therapy for BTK lesions are consistently better when applied in experienced centers with the use of more advanced technology and use of eluting materials. According to limited but randomized evidence, drug-eluting stent (DES) placement might be recommended in BTK lesions under 40 mm long since yields significantly better results than angioplasty alone or implantation of bare metal stents in this lesion subset. Nevertheless, this policy raises doubts on the efficacy of treatment due to limitations in generalizability of outcomes in common hospital settings and related costs. Furthermore, there are still no consistent numbers to provide the efficacy of this approach and long-term data are lacking. Waiting for the long-term results of ongoing trials and new researches, a more comprehensive analysis of outcomes with BTK endovascular first strategy can be provided in the next future.


Assuntos
Arteriopatias Oclusivas/cirurgia , Procedimentos Endovasculares/normas , Isquemia/cirurgia , Perna (Membro)/irrigação sanguínea , Artéria Poplítea , Guias de Prática Clínica como Assunto , Arteriopatias Oclusivas/complicações , Humanos , Isquemia/etiologia , Resultado do Tratamento
9.
Eur J Vasc Endovasc Surg ; 41(2): 256-63, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21130005

RESUMO

OBJECTIVE: Patient- and society-oriented measures of outcome have a critical role in determining the effectiveness of any treatment in patients with critical limb ischaemia (CLI). In particular, the impact of an intervention on patient's dependency and functional performance is relevant but is largely unknown. The aim of the study was to investigate whether the limitations encountered in the activities of daily living (ADLs) measured with the Katz Index (KI) in patients with CLI were changed by the treatment. METHODS: During the period 2006-2008, 248 consecutive patients undergoing repair for CLI were investigated with an ADL questionnaire for assessing KI before and after a mean of 16.19 months from treatment. Changes in KI were stratified by type of treatment and outcome. RESULTS: There were 165 males and 83 females, mean age 73.3 ± 8.3 years; 125 patients showed tissue loss and 123 rest pain alone, 98 received surgical bypass and 150 endovascular repair. Pre-operative KI mean was 10.42. At the post-operative assessment, there was significant worsening in patients' functional outcome (mean KI decreased to 9.78) despite relief of pain (81.5%), tissue healing (72%), good vessel patency (83.8%) and low amputation rate (9.7%). Deterioration of KI was not significantly higher in patients undergoing endovascular repair. Patients receiving major amputation started with worse pre-operative functional score (KI mean 9.42) and did further deteriorate (KI mean 7.71) after demolition surgery. However, patients who received successful revascularisation showed deterioration in the dependence index. CONCLUSIONS: Successful vascular treatment is not associated with improved functional ability in patients with CLI, especially when already highly dependent in their activities. Large nationwide preventive and educational programmes should be implemented to prevent irreversible and severe health deterioration in populations with CLI.


Assuntos
Atividades Cotidianas , Procedimentos Endovasculares , Isquemia/terapia , Extremidade Inferior/irrigação sanguínea , Procedimentos Cirúrgicos Vasculares , Idoso , Idoso de 80 Anos ou mais , Amputação Cirúrgica , Análise de Variância , Estado Terminal , Avaliação da Deficiência , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Isquemia/diagnóstico , Isquemia/fisiopatologia , Isquemia/cirurgia , Itália , Salvamento de Membro , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Reoperação , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução Vascular , Procedimentos Cirúrgicos Vasculares/efeitos adversos
10.
Breast Cancer Res Treat ; 47(1): 57-62, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9493976

RESUMO

MDA-468 human breast cancer cells overexpress the EGFR and exhibit a functional TGFalpha-EGFR autocrine pathway. Loss of EGFR expression following stable transfection with an antisense EGFR cDNA containing plasmid down-regulates type I cAMP-dependent protein kinase (PKAI) expression with acquisition of cell growth resistance to the PKAI inhibitor 8-Cl-cAMP. These results suggest that PKAI expression and function are controlled by a TGFalpha-EGFR autocrine pathway in human breast cancer cells overexpressing the EGFR.


Assuntos
Neoplasias da Mama/enzimologia , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , DNA Antissenso/farmacologia , Receptores ErbB/fisiologia , 8-Bromo Monofosfato de Adenosina Cíclica/análogos & derivados , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/genética , Regulação para Baixo , Receptores ErbB/genética , Feminino , Humanos , Transfecção , Fator de Crescimento Transformador alfa/fisiologia , Células Tumorais Cultivadas
11.
Cancer Res ; 57(22): 5107-11, 1997 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-9371510

RESUMO

8-Chloro-cAMP (8-Cl-cAMP) is a novel agent that is able to inhibit the growth of a wide variety of cancer cell types in vitro and in vivo and, at doses devoid of toxicity, to achieve plasma concentrations in cancer patients in a range effective for cancer cell growth inhibition. In this study, we have demonstrated that 8-Cl-cAMP, at a dose causing mild or no growth inhibition, synergistically increased the growth-inhibitory effect of paclitaxel or cisplatin in a wide series of cell lines including human breast, lung, ovary, colon, and head carcinomas and melanoma. A similar effect was also observed with another taxane, docetaxel, and with the platinum-derivative carboplatin. 8-Cl-cAMP also markedly enhanced apoptotic cell death induced by each cytotoxic drug. A cooperative antitumor effect was also observed in vivo, because treatment with paclitaxel followed by 8-Cl-cAMP markedly inhibited the growth of GEO human colon cancer xenografts as compared to paclitaxel alone without signs of toxicity. These data demonstrate that 8-Cl-cAMP synergistically increases the antiproliferative activity of taxanes and platinum-derived compounds and provide a rationale to use 8-Cl-cAMP in combination with taxanes and platinum-derived compounds.


Assuntos
8-Bromo Monofosfato de Adenosina Cíclica/análogos & derivados , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Cisplatino/farmacologia , Paclitaxel/farmacologia , Ensaio Tumoral de Célula-Tronco/métodos , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Animais , Apoptose/genética , Divisão Celular/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Fase G2 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitose , Transplante de Neoplasias , Transplante Heterólogo , Células Tumorais Cultivadas/efeitos dos fármacos
12.
Clin Cancer Res ; 2(1): 207-14, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9816108

RESUMO

The sensitivity of human tumor cells to activated lymphocytes is considered to play an essential role in the antitumor activity of recombinant interleukin-2 (rIL-2)-based immunotherapy. We have investigated the effects of several genes involved in the regulation of cell growth and transformation on the sensitivity of human mammary epithelial MCF-10A cells to non-MHC-restricted, rIL-2-activated lymphocytes. Therefore, the lysability of MCF-10A cells overexpressing activated oncogenes (Ha-ras, erbB-2, and a mutated p53), growth factors [transforming growth factor alpha (TGFalpha)], or cAMP-dependent protein kinase A subunits (RIalpha, RIIbeta, and Calpha) was evaluated comparatively at different effector:target ratios by a 51Cr release assay. Parental MCF-10A, MCF-10A p53-mutated, and MCF-10A RIIbeta cells showed an intermediate sensitivity. Lysability was increased significantly in MCF-10A Ha-ras, MCF-10A TGFalpha, and MCF-10A RIalpha cells, reduced in MCF-10A Calpha cells, and completely abrogated in MCF-10A erbB-2 cells. These differences could not be explained by simple changes in the cell surface expression of MHC class I and intercellular adhesion molecule-1 proteins or by secretion of TGFbeta. Treatment with TAb 250, a mouse anti-p185(erbB-2) monoclonal antibody, or down-regulation of p185(erbB-2) expression resulted in circumvention of MCF-10A erbB-2 cell resistance. We conclude that molecular changes at the single-gene level resulting in alterations of intracellular signaling and/or cell transformation modulate sensitivity of human mammary epithelial cells to non-MHC-restricted, rIL-2-induced cytotoxicity, regardless of MHC class I and/or intercellular adhesion molecule-1 expression or TGFbeta secretion. Furthermore, anti-p185(erbB-2) monoclonal antibodies may be useful as adjuncts to rIL-2 treatment in patients with erbB-2-overexpressing tumors.


Assuntos
Neoplasias da Mama/imunologia , Proteínas Quinases Dependentes de AMP Cíclico/fisiologia , Citotoxicidade Imunológica , Genes erbB-2 , Interleucina-2/farmacologia , Linfócitos/imunologia , Animais , Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Feminino , Antígenos de Histocompatibilidade Classe I/análise , Humanos , Molécula 1 de Adesão Intercelular/análise , Células Matadoras Ativadas por Linfocina/imunologia , Camundongos , Proteínas Recombinantes/farmacologia , Fator de Crescimento Transformador beta/biossíntese , Células Tumorais Cultivadas
13.
Clin Cancer Res ; 1(2): 161-7, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9815969

RESUMO

8-Chloro-cyclic AMP (8-Cl-cAMP), a site-selective cAMP analogue, is a specific inhibitor of type I cAMP-dependent protein kinase (PKAI) and induces growth inhibition in several human and rodent tumor cell lines. The anti-epidermal growth factor receptor (EGFR) mAb 528 is a blocking antibody able to inhibit the in vitro and in vivo growth of several human cancer cell lines that express functional EGFRs. Since enhanced levels of PKAI are generally found in tumor cells and an increase in PKAI expression is induced by transformation through a transforming growth factor alpha/EGFR autocrine pathway, we have evaluated whether treatment with mAb 528 in combination with 8-Cl-cAMP may have an additive or synergistic growth inhibitory effect on human cancer cells. A dose-dependent inhibition of monolayer cell growth was observed in two human colon cancer cell lines (GEO and CBS) and in a human breast cancer cell line (MDA-468) by treatment with either mAb 528 or 8-Cl-cAMP with 50% inhibitory concentration of 2-10 microgram/ml or 20-25 micrometer, respectively. The combined treatment with low noninhibitory doses of mAb 528 (0.25 microgram/ml) and with 8-Cl-cAMP had a more than additive growth inhibitory effect with a 3- to 5-fold reduction in the 8-Cl-cAMP 50% inhibitory concentration in all cell lines tested. This combined treatment was similarly effective in inhibiting the soft agar cloning efficiency of GEO cells. 8-Cl-cAMP treatment of GEO cells induced a dose-dependent increase in cell membrane-associated EGFRs with a maximum 3- to 4-fold increase within 48-72 h of treatment. These results suggest that a double blockade of the PKAI serine-threonine kinase-dependent and of the EGFR tyrosine kinase-dependent pathways is potentially useful in cancer therapy.


Assuntos
8-Bromo Monofosfato de Adenosina Cíclica/análogos & derivados , Anticorpos Monoclonais/toxicidade , Antineoplásicos/toxicidade , Neoplasias da Mama/patologia , Ciclo Celular/fisiologia , Fragmentação do DNA/fisiologia , Receptores ErbB/imunologia , 8-Bromo Monofosfato de Adenosina Cíclica/toxicidade , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/análise , Receptores ErbB/fisiologia , Feminino , Humanos , Cinética , Células Tumorais Cultivadas
14.
Clin Cancer Res ; 1(1): 49-56, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9815886

RESUMO

Topoisomerase II (Topo II) is an essential enzyme that catalyzes the breakage of double-strand DNA and is the target of several effective anticancer drugs, including the epipodophyllotoxins. The regulatory subunits of the cyclic AMP-dependent protein kinase are differentially expressed in normal and cancer cells. The RIalpha subunit is overexpressed in cells transformed by transforming growth factor-alpha (TGF-alpha) or Ha-ras oncogene. It has been shown that murine cells transformed by Ha-ras become hypersensitive to Topo II-targeting anticancer drugs. In this report we have tested whether any correlation exists between the expression of RIalpha protein and cellular sensitivity of Topo II-targeting drugs. Normal human breast MCF-10A cells and their derivatives overexpressing TGF-alpha, Ha-ras, or the different protein kinase subunits were treated with either Topo II inhibitors, such as etoposide, teniposide, or amsacrine, or with drugs which act independently of Topo II, such as bleomycin. Here we show that MCF-10A TGF-alpha and MCF-10A Ha-ras cells overexpress the RIalpha protein and become hypersensitive to epypodophyllotoxins and amsacrine but not to bleomycin. Direct introduction of the RIalpha gene into MCF-10A induces hypersensitivity to Topo II inhibitor drugs. In contrast, the overexpression of the other protein kinase subunits, RIIbeta or Calpha, does not modify the drug sensitivity of MCF-10A cells. No differences in the mRNA/protein content or in the activity of Topo II were found between hypersensitive cells and parental MCF-10A cells, suggesting that RIalpha may influence drug sensitivity via modulation of events downstream of the Topo II-DNA cleavable complex.


Assuntos
Amsacrina/toxicidade , Bleomicina/toxicidade , Proteínas Quinases Dependentes de AMP Cíclico/genética , Etoposídeo/toxicidade , Genes ras , Teniposídeo/toxicidade , Inibidores da Topoisomerase II , Fator de Crescimento Transformador alfa/fisiologia , Neoplasias da Mama , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Proteína Quinase Tipo II Dependente de AMP Cíclico , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , DNA Topoisomerases Tipo II/genética , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas Recombinantes/metabolismo , Transfecção , Fator de Crescimento Transformador alfa/genética , Células Tumorais Cultivadas
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