VEGF gene therapy cooperatively recruits molecules from the immune system and stimulates cell homing and angiogenesis in refractory angina.

BACKGROUND: New vessels are formed in response to stimuli from angiogenic factors, a process in which paracrine signaling is fundamental. OBJECTIVE: To investigate the cooperative paracrine signaling profile in response to Vascular Endothelial Growth Factor (VEGF) gene therapy in patients with coronary artery disease (CAD) and refractory angina. METHOD: A cohort study was conducted in which plasma was collected from patients who underwent gene therapy with a plasmid expressing VEGF 165 (10) and from surgical procedure controls (4). Blood samples were collected from both groups prior to baseline and on days 3, 9 and 27 after the interventions and subjected to systemic analysis of protein expression (Interleukin-6, IL-6; Tumor Necrosis Factor-α, TNF-α; Interleukin-10, IL-10; Stromal Derived Factor-1 α, SDF-1α; VEGF; Angiopoietin-1, ANGPT-1; and Endothelin-1, ET-1) using the enzyme-linked immunosorbent assay (ELISA). RESULTS: Analysis showed an increase in proinflammatory IL-6 (p=0.02) and ET-1 (p=0.05) on day 3 after gene therapy and in VEGF (p=0.02) on day 9. A strong positive correlation was found between mobilization of endothelial progenitor cells and TNF-α on day 9 (r=0.71; p=0.03). Furthermore, a strong correlation between ß-blockers, antiplatelets, and vasodilators with SDF-1α baseline in the group undergoing gene therapy was verified (r=0.74; p=0.004). CONCLUSION: Analysis of cooperative paracrine signaling after VEGF gene therapy suggests that the immune system cell and angiogenic molecule expression as well as the endothelial progenitor cell mobilization are time-dependent, influenced by chronic inflammatory process and continuous pharmacological treatment.

VEGF 165 gene therapy for patients with refractory angina: mobilization of endothelial progenitor cells.

BACKGROUND: Vascular endothelial growth factor (VEGF) induces mobilization of endothelial progenitor cells (EPCs) with the capacity for proliferation and differentiation into mature endothelial cells, thus contributing to the angiogenic process. OBJECTIVE: We sought to assess the behavior of EPCs in patients with ischemic heart disease and refractory angina who received an intramyocardial injections of 2000 µg of VEGF 165 as the sole therapy. METHODS: The study was a subanalysis of a clinical trial. Patients with advanced ischemic heart disease and refractory angina were assessed for eligibility. Inclusion criteria were as follows: signs and symptoms of angina and/or heart failure despite maximum medical treatment and a myocardial ischemic area of at least 5% as assessed by single-photon emission computed tomography (SPECT). Exclusion criteria were as follows: age > 65 years, left ventricular ejection fraction < 25%, and a diagnosis of cancer. Patients whose EPC levels were assessed were included. The intervention was 2000 µg of VEGF 165 plasmid injected into the ischemic myocardium. The frequency of CD34+/KDR+ cells was analyzed by flow cytometry before and 3, 9, and 27 days after the intervention. RESULTS: A total of 9 patients were included, 8 males, mean age 59.4 years, mean left ventricular ejection fraction of 59.3% and predominant class III angina. The number of EPCs on day 3 was significantly higher than that at baseline (p = 0.03); however, that on days 9 and 27 was comparable to that at baseline. CONCLUSION: We identified a transient mobilization of EPCs, which peaked on the 3th day after VEGF 165 gene therapy in patients with refractory angina and returned to near baseline levels on days 9 and 27.

High doses of vascular endothelial growth factor 165 safely, but transiently, improve myocardial perfusion in no-option ischemic disease.

UNLABELLED: Gene therapy can induce angiogenesis in ischemic tissues. The aim of this study was to assess safety, feasibility, and results, both clinical and on myocardial perfusion, of gene therapy in refractory angina. This was a phase I/II, prospective, temporal-controlled series, clinical trial. Thirteen patients were maintained for minimum 6 months under optimized clinical management, and then received intramyocardial injections of 2000 µg plasmid vascular endothelial growth factor 165 and were followed by single-photon emission computed tomography (SPECT), treadmill tests, Minnesota quality of life questionnaire (QOL), and New York Heart Association (NYHA) functional plus Canadian Cardiovascular Society (CCS) angina classifications. There were no deaths, early or late. During the optimized clinical treatment, we observed worsening of rest ischemia scores on SPECT (p<0.05). After treatment, there was a transitory increase in myocardial perfusion at the third-month SPECT under stress (pre-operative [pre-op] 18.38 ± 7.51 vs. 3 months 15.31 ± 7.30; p<0.01) and at the sixth month under rest (pre-op 13.23 ± 7.98 vs. 6 months: 16.92 ± 7.27; p<0.01). One year after, there were improvements in treadmill test steps (pre-op 2.46 ± 2.07 vs.12 months 4.15 ± 2.23; p<0.01) and oxygen consumption (pre-op 7.66 ± 4.47 vs.12 months 10.89 ± 4.65; p<0.05), QOL (pre-op 48.23 ± 18.35 vs.12 months 28.31 ± 18.14; p<0.01) scores, and CCS (pre-op 3 [3-3.5] vs.12 months 2 [1-2.5]; p<0.01) and NYHA (pre-op 3 [3-3] vs. 2 [2-2] vs. 12 months 2 [1-2]; p<0.01) classes. Gene therapy demonstrated to be feasible and safe in this advanced ischemic cardiomyopathy patient sample. There were improvements in clinical evaluation parameters, and a transitory increase in myocardial perfusion detectable by SPECT scintigraphy. CLINICAL TRIAL REGISTRATION: NCT00744315 http://clinicaltrials.gov/

Gene therapy for ischemic heart disease: review of clinical trials.

Severe ischemic heart disease with refractory angina, occurs in increasing incidence. Alternative forms of treatment, in an attempt to reduce myocardial ischemia and relief of symptoms has been studied. In this context, gene therapy is an option, for the possibility of inducing angiogenesis, establish collateral circulation and reperfuse ischemic myocardium. Several clinical trials have been conducted and, except for specific cases of adverse effects, there is indication of safety, feasibility and potential effectiveness of therapy. The clinical benefit, however, is not yet well established. In this article we review the clinical trials of gene therapy for patients with ischemic heart disease. The approach includes: (1) myocardial ischemia and angiogenesis on the pathophysiological aspects involved, (2) growth factors, dealing with specific aspects and justifying the use in cardiac patients with no option for conventional therapy, (3) controlled clinical trials, where a summary of the main studies involving gene therapy for severe ischemic heart disease is presented, (4) our experience, especially on preliminary results of the first gene therapy clinical trial in Brazil and (5) future prospects.

Terapia gênica com fator de crescimento endotelial vascular 165 para pacientes com angina refratária: mobilização de células progenitoras endoteliais / VEGF 165 gene therapy for patients with refractory angina: mobilization of endothelial progenitor cells

FUNDAMENTO: O fator de crescimento endotelial vascular (VEGF - vascular endothelial growth factor) induz a mobilização de células progenitoras endoteliais (CPEs) com capacidade de proliferação e diferenciação em células endoteliais, contribuindo, dessa forma, para o processo angiogênico. OBJETIVO: Buscamos avaliar o comportamento de CPEs em pacientes com doença cardíaca isquêmica e angina refratária que receberam injeções intramiocardicas de 2000 µg de VEGF165 como terapia única. MÉTODOS: O estudo foi uma subanálise de um ensaio clínico. Pacientes com doença cardíaca isquêmica avançada e angina refratária foram avaliados para inclusão no estudo. Os critérios de inclusão foram: sinais e sintomas de angina e/ou insuficiência cardíaca apesar de tratamento medicamentoso máximo e área de isquemia miocárdica de, no mínimo, 5% conforme avaliado por uma tomografia computadorizada por emissão de fóton único (TCEFU). Os critérios de exclusão foram: idade > 65 anos, fração de ejeção do ventrículo esquerdo < 25% e cancer diagnosticado. Os pacientes cujos níveis de CPE foram avaliados foram incluídos. A intervenção consistiu na administração de 2000 µg de VEGF 165 de plasmídeo injetado no miocárdio isquêmico. A frequência de células CD34+/KDR+ foi analisada por citometria de fluxo antes e 3, 9, e 27 dias após a intervenção. RESULTADOS: Um total de 9 pacientes foram incluídos, 8 homens, média de idade de 59,4 anos, fração de ejeção ventricular esquerda de 59,3%, e classe de angina predominante III. Observou-se um aumento significativo dos níveis de CPEs no terceiro dia após a intervenção. Todavia, 9 e 27 dias após a intervenção, os níveis de CPEs foram similares aos basais. CONCLUSÃO: Identificamos uma mobilização transitória de CPE, com pico no terceiro dia após a intervenção com VEGF 165 em pacientes com angina refratária. Todavia, os níveis de CPEs apresentaram-se semelhantes aos basais 9 e 27 dias após a intervenção.

BACKGROUND: Vascular endothelial growth factor (VEGF) induces mobilization of endothelial progenitor cells (EPCs) with the capacity for proliferation and differentiation into mature endothelial cells, thus contributing to the angiogenic process. OBJECTIVE: We sought to assess the behavior of EPCs in patients with ischemic heart disease and refractory angina who received an intramyocardial injections of 2000 µg of VEGF 165 as the sole therapy. METHODS: The study was a subanalysis of a clinical trial. Patients with advanced ischemic heart disease and refractory angina were assessed for eligibility. Inclusion criteria were as follows: signs and symptoms of angina and/or heart failure despite maximum medical treatment and a myocardial ischemic area of at least 5% as assessed by single-photon emission computed tomography (SPECT). Exclusion criteria were as follows: age > 65 years, left ventricular ejection fraction < 25%, and a diagnosis of cancer. Patients whose EPC levels were assessed were included. The intervention was 2000 µg of VEGF 165 plasmid injected into the ischemic myocardium. The frequency of CD34+/KDR+ cells was analyzed by flow cytometry before and 3, 9, and 27 days after the intervention. RESULTS: A total of 9 patients were included, 8 males, mean age 59.4 years, mean left ventricular ejection fraction of 59.3% and predominant class III angina. The number of EPCs on day 3 was significantly higher than that at baseline (p = 0.03); however, that on days 9 and 27 was comparable to that at baseline. CONCLUSION: We identified a transient mobilization of EPCs, which peaked on the 3th day after VEGF 165 gene therapy in patients with refractory angina and returned to near baseline levels on days 9 and 27.

Terapia gênica para cardiopatia isquêmica: revisão de ensaios clínicos / Gene therapy for ischemic heart disease: review of clinical trials

Cardiopatia isquêmica grave com angina refratária a formas convencionais de tratamento apresenta-se em uma crescente incidência. Para tratar angina refratária, terapias alternativas na tentativa de redução da isquemia miocárdica e alívio de sintomas têm sido estudadas. Neste contexto, a terapia gênica representa uma opção, pela possibilidade de induzir angiogênese, estabelecer circulação colateral e reperfundir miocárdio isquêmico. Diversos ensaios clínicos têm sido conduzidos e, com exceção de casos isolados e específicos de efeitos adversos, há indicação de segurança, viabilidade e potencial eficácia da terapia. O benefício clínico não está bem definido. Neste artigo, revisamos os ensaios clínicos que utilizaram terapia gênica para tratamento de pacientes cardiopatas isquêmicos. A abordagem inclui: (1) isquemia miocárdica e angiogênese, sobre os aspectos fisiopatológicos envolvidos; (2) fatores de crescimento, tratando sobre aspectos específicos e justificando a utilização em pacientes cardiopatas isquêmicos sem opções pela terapêutica convencional; (3) ensaios clínicos controlados, onde é apresentado um resumo dos principais estudos envolvendo terapia gênica para tratamento da cardiopatia isquêmica grave; (4) nossa experiência, especialmente sobre resultados preliminares do primeiro ensaio clínico de terapia gênica do Brasil e (5) perspectivas.

Severe ischemic heart disease with refractory angina, occurs in increasing incidence. Alternative forms of treatment, in an attempt to reduce myocardial ischemia and relief of symptoms has been studied. In this context, gene therapy is an option, for the possibility of inducing angiogenesis, establish collateral circulation and reperfuse ischemic myocardium. Several clinical trials have been conducted and, except for specific cases of adverse effects, there is indication of safety, feasibility and potential effectiveness of therapy. The clinical benefit, however, is not yet well established. In this article we review the clinical trials of gene therapy for patients with ischemic heart disease. The approach includes: (1) myocardial ischemia and angiogenesis on the pathophysiological aspects involved, (2) growth factors, dealing with specific aspects and justifying the use in cardiac patients with no option for conventional therapy, (3) controlled clinical trials, where a summary of the main studies involving gene therapy for severe ischemic heart disease is presented, (4) our experience, especially on preliminary results of the first gene therapy clinical trial in Brazil and (5) future prospects.