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1.
J Appl Toxicol ; 44(5): 666-685, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37697914

RESUMO

Snake venom contains a cocktail of compounds dominated by proteins and peptides, which make up the toxin. The toxin components of snake venom attack several targets in the human body including the neuromuscular system, kidney and blood coagulation system and cause pathologies. As such, the venom toxins can be managed and used for the treatment of these diseases. In this regard, Captopril used in the treatment of cardiovascular diseases was the first animal venom toxin-based drug approved by the US Food and Drug Administration and the European Medicines Agency. Cancers cause morbidity and mortality worldwide. Due to side effects associated with the current cancer treatments including chemotherapy, radiotherapy, immunotherapy, hormonal therapy and surgery, there is a need to improve the efficacy of current treatments and/or develop novel drugs from natural sources including animal toxin-based drugs. There is a long history of earlier and ongoing studies implicating snake venom toxins as potential anticancer therapies. Here, we review the role of crude snake venoms and toxins including phospholipase A2, L-amino acid oxidase, C-type lectin and disintegrin as potential anticancer agents tested in cancer cell lines and animal tumour models in comparison to normal cell lines. Some of the anti-tumour activities of snake venom toxins include induction of cytotoxicity, apoptosis, cell cycle arrest and inhibition of metastasis, angiogenesis and tumour growth. We thus propose the advancement of multidisciplinary approaches to more pre-clinical and clinical studies for enhanced bioavailability and targeted delivery of snake venom toxin-based anticancer drugs.


Assuntos
Antineoplásicos , Doenças Cardiovasculares , Neoplasias , Estados Unidos , Animais , Humanos , Venenos de Serpentes/farmacologia , Venenos de Serpentes/uso terapêutico , Venenos de Serpentes/química , Coagulação Sanguínea , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico
2.
J Toxicol Environ Health B Crit Rev ; 24(1): 30-50, 2021 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-33308037

RESUMO

One of the factors responsible for lack of reproducible findings may be attributed to the raw material used. To date, there are no apparent studies examining reproducibility using venoms for the development of new toxin-based drugs with respect to regulatory agencies' policies. For this reason, protocols were implemented to produce animal toxins with quality, traceability, and strict compliance with Good Manufacturing Practices. This required validation of the production chain from the arrival of the animal to the vivarium, followed by handling, housing, as well as compliance with respect to extraction, freeze-drying, and, finally, storage protocols, aimed at generating compounds to serve as candidate molecules applicable in clinical trials. Currently, to produce quality snake venoms to support reproductive studies, the Center for the Study of Venoms and Venomous Animals (CEVAP) from São Paulo State University (UNESP), São Paulo, Brazil has 449 microchipped snakes through rigid and standardized operating procedures for safety, health, and welfare of animals. Snakes were frequently subjected to vet clinical examination, anthelmintic, and antiparasitic treatment. Venom milk used to destroy prey was collected from each animal in individual plastic microtubes to avoid contamination and for traceability. In addition, venoms were submitted to microbiological, and biochemical toxicological analyses. It is noteworthy that investigators are responsible for caring, maintaining, and manipulating snakes and ensuring their health in captivity. This review aimed to contribute to the pharmaceutical industry the experimental experience and entire snake venom production chain required to generate quality products for therapeutic human consumption.


Assuntos
Produtos Biológicos/uso terapêutico , Indústria Farmacêutica/normas , Venenos de Serpentes/uso terapêutico , Animais , Produtos Biológicos/normas , Brasil , Desenvolvimento de Medicamentos/legislação & jurisprudência , Desenvolvimento de Medicamentos/normas , Humanos , Reprodutibilidade dos Testes , Serpentes
3.
Molecules ; 26(8)2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33921462

RESUMO

Cardiovascular diseases (CVDs) are considered as a major cause of death worldwide. Therefore, identifying and developing therapeutic strategies to treat and reduce the prevalence of CVDs is a major medical challenge. Several drugs used for the treatment of CVDs, such as captopril, emerged from natural products, namely snake venoms. These venoms are complex mixtures of bioactive molecules, which, among other physiological networks, target the cardiovascular system, leading to them being considered in the development and design of new drugs. In this review, we describe some snake venom molecules targeting the cardiovascular system such as phospholipase A2 (PLA2), natriuretic peptides (NPs), bradykinin-potentiating peptides (BPPs), cysteine-rich secretory proteins (CRISPs), disintegrins, fibrinolytic enzymes, and three-finger toxins (3FTXs). In addition, their molecular targets, and mechanisms of action-vasorelaxation, inhibition of platelet aggregation, cardioprotective activities-are discussed. The dissection of their biological effects at the molecular scale give insights for the development of future snake venom-derived drugs.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Venenos de Serpentes/química , Venenos de Serpentes/uso terapêutico , Animais , Fármacos Cardiovasculares/farmacologia , Fármacos Cardiovasculares/uso terapêutico , Sistema Cardiovascular/efeitos dos fármacos , Sistema Cardiovascular/patologia , Humanos , Modelos Biológicos , Venenos de Serpentes/farmacologia
4.
J Cell Mol Med ; 23(8): 4876-4882, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31210419

RESUMO

Despite aggressive multimodality treatment, the prognosis of glioma, especially malignant glioma, remains very poor. After decades of effort, anti-angiogenic therapy has become an important method of cancer treatment in addition to surgery, radiotherapy and chemotherapy. Although the performance of anti-angiogenic therapy in colorectal cancer is good, its performance in malignant glioma remains unsatisfactory. Several phase III clinical trials showed no overall survival benefits. To solve this problem, the division of patients into groups based on their molecular biomarkers is an important step. This paper provides current insights into anti-angiogenic drugs undergoing clinical trials and discusses the potential of molecular biomarkers to guide glioma diagnosis.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Inibidores da Angiogênese/farmacologia , Bevacizumab/farmacologia , Bevacizumab/uso terapêutico , Biomarcadores Tumorais/sangue , Neoplasias Encefálicas/classificação , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/metabolismo , Glioma/classificação , Glioma/enzimologia , Glioma/metabolismo , Humanos , Indóis/farmacologia , Indóis/uso terapêutico , Terapia de Alvo Molecular , Prognóstico , Venenos de Serpentes/farmacologia , Venenos de Serpentes/uso terapêutico
5.
Cochrane Database Syst Rev ; 11: CD008218, 2018 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-30480778

RESUMO

BACKGROUND: This is an updated version of the original Cochrane Review published in September 2014. The most common primary brain tumours in adults are gliomas. Gliomas span a spectrum from low to high grade and are graded pathologically on a scale of one to four according to the World Health Organization (WHO) classification. High-grade glioma (HGG) carries a poor prognosis. Grade IV glioma is known as glioblastoma and carries a median survival in treated patients of about 15 months. Glioblastomas are rich in blood vessels (i.e. highly vascular) and also rich in a protein known as vascular endothelial growth factor (VEGF) that promotes new blood vessel formation (the process of angiogenesis). Anti-angiogenic agents inhibit the process of new blood vessel formation and promote regression of existing vessels. Several anti-angiogenic agents have been investigated in clinical trials, both in newly diagnosed and recurrent HGG, showing preliminary promising results. This review was undertaken to report on the benefits and harms associated with the use of anti-angiogenic agents in the treatment of HGGs. OBJECTIVES: To evaluate the efficacy and toxicity of anti-angiogenic therapy in people with high-grade glioma (HGG). The intervention can be used in two broad groups: at first diagnosis as part of 'adjuvant' therapy, or in the setting of recurrent disease. SEARCH METHODS: We conducted updated searches to identify published and unpublished randomised controlled trials (RCTs), including the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 9), MEDLINE and Embase to October 2018. We handsearched proceedings of relevant oncology conferences up to 2018. We also searched trial registries for ongoing studies. SELECTION CRITERIA: RCTs evaluating the use of anti-angiogenic therapy to treat HGG versus the same therapy without anti-angiogenic therapy. DATA COLLECTION AND ANALYSIS: Review authors screened the search results and reviewed the abstracts of potentially relevant articles before retrieving the full text of eligible articles. MAIN RESULTS: After a comprehensive literature search, we identified 11 eligible RCTs (3743 participants), of which 7 were included in the original review (2987 participants). There was significant design heterogeneity in the included studies, especially in the response assessment criteria used. All eligible studies were restricted to glioblastomas and there were no eligible studies evaluating other HGGs. Ten studies were available as fully published peer-reviewed manuscripts, and one study was available in abstract form. The overall risk of bias in included studies was low. This risk was based upon low rates of selection bias, detection bias, attrition bias and reporting bias. The 11 studies included in this review did not show an improvement in overall survival with the addition of anti-angiogenic therapy (pooled hazard ratio (HR) of 0.95, 95% confidence interval (CI) 0.88 to 1.02; P = 0.16; 11 studies, 3743 participants; high-certainty evidence). However, pooled analysis from 10 studies (3595 participants) showed improvement in progression-free survival with the addition of anti-angiogenic therapy (HR 0.73, 95% CI 0.68 to 0.79; P < 0.00001; high-certainty evidence).We carried out additional analyses of overall survival and progression-free survival according to treatment setting and for anti-angiogenic therapy combined with chemotherapy compared to chemotherapy alone. Pooled analysis of overall survival in either the adjuvant or recurrent setting did not show an improvement (HR 0.93, 95% CI 0.86 to 1.02; P = 0.12; 8 studies, 2833 participants; high-certainty evidence and HR 0.99, 95% CI 0.85 to 1.16; P = 0.90; 3 studies, 910 participants; moderate-certainty evidence, respectively). Pooled analysis of overall survival for anti-angiogenic therapy combined with chemotherapy compared to chemotherapy also did not clearly show an improvement (HR 0.92, 95% CI 0.85 to 1.00; P = 0.05; 11 studies, 3506 participants; low-certainty evidence). The progression-free survival in the subgroups all showed findings that demonstrated improvements in progression-free survival with the addition of anti-angiogenic therapy. Pooled analysis of progression-free survival in both the adjuvant and recurrent setting showed an improvement (HR 0.75, 95% CI 0.69 to 0.82; P < 0.00001; 8 studies, 2833 participants; high-certainty evidence and HR 0.64, 95% CI 0.54 to 0.76; P < 0.00001; 2 studies, 762 participants; moderate-certainty evidence, respectively). Pooled analysis of progression-free survival for anti-angiogenic therapy combined with chemotherapy compared to chemotherapy alone showed an improvement (HR 0.72, 95% CI 0.66 to 0.77; P < 0.00001; 10 studies, 3464 participants). Similar to trials of anti-angiogenic therapies in other solid tumours, adverse events related to this class of therapy included hypertension and proteinuria, poor wound healing, and the potential for thromboembolic events, although generally, the rate of grade 3 and 4 adverse events was low (< 14.1%) and in keeping with the literature. The impact of anti-angiogenic therapy on quality of life varied between studies. AUTHORS' CONCLUSIONS: The use of anti-angiogenic therapy does not significantly improve overall survival in newly diagnosed people with glioblastoma. Thus, there is insufficient evidence to support the use of anti-angiogenic therapy for people with newly diagnosed glioblastoma at this time. Overall there is a lack of evidence of a survival advantage for anti-angiogenic therapy over chemotherapy in recurrent glioblastoma. When considering the combination anti-angiogenic therapy with chemotherapy compared with the same chemotherapy alone, there may possibly be a small improvement in overall survival. While there is strong evidence that bevacizumab (an anti-angiogenic drug) prolongs progression-free survival in newly diagnosed and recurrent glioblastoma, the impact of this on quality of life and net clinical benefit for patients remains unclear. Not addressed here is whether subsets of people with glioblastoma may benefit from anti-angiogenic therapies, nor their utility in other HGG histologies.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Inibidores da Angiogênese/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos/uso terapêutico , Bevacizumab/uso terapêutico , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/mortalidade , Camptotecina/análogos & derivados , Camptotecina/uso terapêutico , Dacarbazina/análogos & derivados , Dacarbazina/uso terapêutico , Glioblastoma/irrigação sanguínea , Glioblastoma/mortalidade , Humanos , Hipertensão/induzido quimicamente , Irinotecano/uso terapêutico , Lomustina/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Neovascularização Patológica/mortalidade , Intervalo Livre de Progressão , Proteinúria/induzido quimicamente , Ensaios Clínicos Controlados Aleatórios como Assunto , Venenos de Serpentes/uso terapêutico , Temozolomida/uso terapêutico
6.
Molecules ; 23(3)2018 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-29562696

RESUMO

Cancer represents the disease of the millennium, a major problem in public health. The proliferation of tumor cells, angiogenesis, and the relationship between the cancer cells and the components of the extracellular matrix are important in the events of carcinogenesis, and these pathways are being used as targets for new anticancer treatments. Various venoms and their toxins have shown possible anticancer effects on human cancer cell lines, providing new perspectives in drug development. In this review, we observed the effects of natural toxins from bee and snake venom and the mechanisms through which they can inhibit the growth and proliferation of cancer cells. We also researched how several types of natural molecules from venom can sensitize ovarian cancer cells to conventional chemotherapy, with many toxins being helpful for developing new anticancer drugs. This approach could improve the efficiency of standard therapies and could allow the administration of decreased doses of chemotherapy. Natural toxins from bee and snake venom could become potential candidates for the future treatment of different types of cancer. It is important to continue these studies concerning therapeutic drugs from natural resource and, more importantly, to investigate their mechanism of action on cancer cells.


Assuntos
Antineoplásicos/uso terapêutico , Venenos de Abelha/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Venenos de Serpentes/uso terapêutico , Animais , Antineoplásicos/farmacologia , Venenos de Abelha/farmacologia , Carcinogênese/efeitos dos fármacos , Carcinogênese/metabolismo , Carcinogênese/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Venenos de Serpentes/farmacologia
7.
Br J Haematol ; 177(6): 947-959, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28233897

RESUMO

Snake venoms are mixtures of numerous proteinacious components that exert diverse functional activities on a variety of physiological targets. Because the toxic constituents found in venom vary from species to species, snakebite victims can present with a variety of life-threatening pathologies related to the neurotoxic, cytotoxic and haemotoxic effects of venom. Of the 1·8 million people envenomed by snakes every year, up to 125 000 die, while hundreds of thousands survive only to suffer with life-changing long-term morbidity. Consequently, snakebite is one of the world's most severe neglected tropical diseases. Many snake venoms exhibit strong haemotoxic properties by interfering with blood pressure, clotting factors and platelets, and by directly causing haemorrhage. In this review we provide an overview of the functional activities of haemotoxic venom proteins, the pathologies they cause in snakebite victims and how their exquisite selectivity and potency make them amenable for use as therapeutic and diagnostic tools relevant for human medicine.


Assuntos
Mordeduras de Serpentes/complicações , Venenos de Serpentes/toxicidade , Animais , Transtornos da Coagulação Sanguínea/etiologia , Hemorragia/etiologia , Humanos , Doenças Negligenciadas , Venenos de Serpentes/uso terapêutico
8.
J Neurooncol ; 128(1): 163-171, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26935578

RESUMO

Newly diagnosed glioblastoma multiforme with unmethylated MGMT promoter has a poor prognosis, with a median survival of 12 months. This phase II study investigated the efficacy and safety of combining the selective integrin inhibitor cilengitide with a combination of metronomic temozolomide and procarbazine for these patients. Eligible patients (newly diagnosed, histologically confirmed supratentorial glioblastoma with unmethylated MGMT promoter) were entered into this multicentre study. Cilengitide (2000 mg IV twice weekly) was commenced 1 week prior to radiotherapy combined with daily temozolomide (60 mg/m(2)) and procarbazine (50 or 100 mg) and, after 4 weeks' break, followed by six adjuvant cycles of temozolomide (50-60 mg/m(2)) and procarbazine (50 or 100 mg) on days 1-20, every 28 days. Cilengitide was continued for up to 12 months or until disease progression or unacceptable toxicity. The primary endpoint for efficacy was a 12-month overall survival rate of 65 %. Twenty-nine patients completed study treatment. Sixteen patients survived for 12 months or more, an overall survival rate of 55 %. The median overall survival was 14.5 months (95 % CI 11.1-19.6) and the median progression-free survival was 7.4 months (95 % CI 6.1-8). Cilengitide combined with metronomic temozolomide and procarbazine in MGMT-promoter unmethylated glioblastoma did not improve survival compared with historical data and does not warrant further investigation.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias do Sistema Nervoso Central/terapia , Dacarbazina/análogos & derivados , Glioblastoma/terapia , Procarbazina/uso terapêutico , Venenos de Serpentes/uso terapêutico , Adulto , Idoso , Antineoplásicos/efeitos adversos , Neoplasias do Sistema Nervoso Central/genética , Quimiorradioterapia/efeitos adversos , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Dacarbazina/efeitos adversos , Dacarbazina/uso terapêutico , Progressão da Doença , Intervalo Livre de Doença , Quimioterapia Combinada , Feminino , Glioblastoma/genética , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Procarbazina/efeitos adversos , Venenos de Serpentes/efeitos adversos , Temozolomida , Falha de Tratamento , Proteínas Supressoras de Tumor/genética , Adulto Jovem
9.
Gen Dent ; 64(1): e10-1, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26742177

RESUMO

This article reviews the hemostatic properties of snake venoms and their potential clinical application.


Assuntos
Odontologia/métodos , Hemostáticos/uso terapêutico , Venenos de Serpentes/uso terapêutico , Humanos
10.
J Neurooncol ; 121(2): 269-78, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25370707

RESUMO

Placenta growth factor (PlGF) is a member of vascular endothelial growth factor family which can promote cancer growth by various mechanisms. Placenta growth factor is upregulated in many neoplastic diseases and serum levels of PlGF are increased in cancer patients following anti-angiogenic therapy. However, its role in glioma growth is yet not fully elucidated. In this study we analyzed the expression of PlGF mRNA using real time PCR in human gliomas of different WHO grades. Placenta growth factor mRNA levels were highly variable and did not correlate with WHO grades, arguing against a significant role in glioma progression. The highest PlGF expression was observed in anaplastic astrocytomas whereas grade II astrocytomas and glioblastomas displayed lower levels of expression. Immunohistochemical analysis showed that PlGF was expressed by inflammatory and endothelial cells in addition to tumor cells. Placenta growth factor mRNA expression in 12 matched glioblastoma samples before and after therapy, including bevacizumab and cilengitide treatment was largely unaffected by the aforementioned treatment modalities. In vitro, the exposure of VEGFR-1 expressing glioma cells to bevacizumab did not increase the expression levels of PlGF mRNA. In summary, our results do not support the hypothesis that PlGF plays a major role in the resistance of gliomas after anti-angiogenic therapy.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/fisiologia , Glioma/tratamento farmacológico , Proteínas da Gravidez/metabolismo , Adulto , Idoso , Anticorpos Monoclonais Humanizados/uso terapêutico , Bevacizumab , Biomarcadores Tumorais/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/cirurgia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Linhagem Celular Tumoral , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Glioma/metabolismo , Glioma/patologia , Glioma/cirurgia , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Fator de Crescimento Placentário , Prognóstico , RNA Mensageiro/metabolismo , Estudos Retrospectivos , Venenos de Serpentes/uso terapêutico , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo
11.
Minerva Gastroenterol Dietol ; 61(2): 71-86, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25610998

RESUMO

Pancreatic ductal adenocarcinoma (PDAC), although tenth in cancer incidence, holds the dubious distinction of being the fifth cause of cancer deaths in the Western countries and possibly the deadliest malignancy. Inoperable PDAC is characterized by late diagnosis, extensive metastases, extremely poor response to chemotherapy and, consequently, poor patients' prognosis-6.7% 5-year survival. PDAC reflects the failure of the medical profession to significantly prolong patients' lives and modest expectations for future cure. PDAC is characterized by extensive desmoplastic reaction, resulting in approximately 50% of tumor's volume consisting of non-tumor cells and extracellular matrix (ECM) stroma. These properties imply an important role for cell-ECM interaction, making cell-matrix adhesion molecules, such as integrins, of special interest as possible candidate targets for future anti-PDAC therapies. This review will attempt to overview the status of studies dealing with the involvement of integrins in the unique aggressive character of PDAC, the current status of experimental cancer therapies targeted at integrins, and the possible application of these preliminary clinical experiments to future PDAC therapy. I will also try to delineate the reasons for the failures of PDAC therapies and make some modest suggestions that might improve the health scientific community approaches to this extremely difficult problem.


Assuntos
Adenocarcinoma/tratamento farmacológico , Integrinas/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Ensaios Clínicos como Assunto , Previsões , Humanos , Venenos de Serpentes/uso terapêutico
12.
Artigo em Alemão | MEDLINE | ID: mdl-26510104

RESUMO

Emergency medical service is called by a 54-year-old man bitten by his rattlesnake. Upon initial survey we find the patient in a cardiopulmonary stable condition. He has bite marks and pain on his rapidly swelling middle finger of his right hand. Our initial treatment is immobilization of the patient. The snake raiser has already called the poison control center in Munich. By the help of this institution we bring him to a hospital having the right antivenom on hand.


Assuntos
Crotalus , Traumatismos dos Dedos/diagnóstico , Traumatismos dos Dedos/terapia , Mordeduras de Serpentes/diagnóstico , Mordeduras de Serpentes/terapia , Venenos de Serpentes/uso terapêutico , Criação de Animais Domésticos , Animais , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
13.
Lancet Oncol ; 15(10): 1100-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25163906

RESUMO

BACKGROUND: Cilengitide is a selective αvß3 and αvß5 integrin inhibitor. Data from phase 2 trials suggest that it has antitumour activity as a single agent in recurrent glioblastoma and in combination with standard temozolomide chemoradiotherapy in newly diagnosed glioblastoma (particularly in tumours with methylated MGMT promoter). We aimed to assess cilengitide combined with temozolomide chemoradiotherapy in patients with newly diagnosed glioblastoma with methylated MGMT promoter. METHODS: In this multicentre, open-label, phase 3 study, we investigated the efficacy of cilengitide in patients from 146 study sites in 25 countries. Eligible patients (newly diagnosed, histologically proven supratentorial glioblastoma, methylated MGMT promoter, and age ≥18 years) were stratified for prognostic Radiation Therapy Oncology Group recursive partitioning analysis class and geographic region and centrally randomised in a 1:1 ratio with interactive voice response system to receive temozolomide chemoradiotherapy with cilengitide 2000 mg intravenously twice weekly (cilengitide group) or temozolomide chemoradiotherapy alone (control group). Patients and investigators were unmasked to treatment allocation. Maintenance temozolomide was given for up to six cycles, and cilengitide was given for up to 18 months or until disease progression or unacceptable toxic effects. The primary endpoint was overall survival. We analysed survival outcomes by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00689221. FINDINGS: Overall, 3471 patients were screened. Of these patients, 3060 had tumour MGMT status tested; 926 patients had a methylated MGMT promoter, and 545 were randomly assigned to the cilengitide (n=272) or control groups (n=273) between Oct 31, 2008, and May 12, 2011. Median overall survival was 26·3 months (95% CI 23·8-28·8) in the cilengitide group and 26·3 months (23·9-34·7) in the control group (hazard ratio 1·02, 95% CI 0·81-1·29, p=0·86). None of the predefined clinical subgroups showed a benefit from cilengitide. We noted no overall additional toxic effects with cilengitide treatment. The most commonly reported adverse events of grade 3 or worse in the safety population were lymphopenia (31 [12%] in the cilengitide group vs 26 [10%] in the control group), thrombocytopenia (28 [11%] vs 46 [18%]), neutropenia (19 [7%] vs 24 [9%]), leucopenia (18 [7%] vs 20 [8%]), and convulsion (14 [5%] vs 15 [6%]). INTERPRETATION: The addition of cilengitide to temozolomide chemoradiotherapy did not improve outcomes; cilengitide will not be further developed as an anticancer drug. Nevertheless, integrins remain a potential treatment target for glioblastoma. FUNDING: Merck KGaA, Darmstadt, Germany.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Dacarbazina/análogos & derivados , Glioblastoma/tratamento farmacológico , Venenos de Serpentes/uso terapêutico , Proteínas Supressoras de Tumor/genética , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Intervalos de Confiança , Dacarbazina/uso terapêutico , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Esquema de Medicação , Detecção Precoce de Câncer/métodos , Feminino , Seguimentos , Glioblastoma/genética , Glioblastoma/mortalidade , Glioblastoma/patologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Seleção de Pacientes , Regiões Promotoras Genéticas , Modelos de Riscos Proporcionais , Valores de Referência , Análise de Sobrevida , Temozolomida , Resultado do Tratamento
14.
Ann Oncol ; 25(3): 682-688, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24567516

RESUMO

BACKGROUND: Recurrent and/or metastatic squamous cell carcinoma of the head and neck (R/M-SCCHN) overexpresses αvß5 integrin. Cilengitide selectively inhibits αvß3 and αvß5 integrins and is investigated as a treatment strategy. PATIENTS AND METHODS: The phase I/II study ADVANTAGE evaluated cilengitide combined with cisplatin, 5-fluorouracil, and cetuximab (PFE) in R/M-SCCHN. The phase II part reported here was an open-label, randomized, controlled trial investigating progression-free survival (PFS). Patients received up to six cycles of PFE alone or combined with cilengitide 2000 mg once (CIL1W) or twice (CIL2W) weekly. Thereafter, patients received maintenance therapy (cilengitide arms: cilengitide plus cetuximab; PFE-alone arm: cetuximab only) until disease progression or unacceptable toxicity. RESULTS: One hundred and eighty-two patients were treated. Median PFS per investigator read was similar for CIL1W + PFE, CIL2W + PFE, and PFE alone (6.4, 5.6, and 5.7 months, respectively). Accordingly, median overall survival and objective response rates were not improved with cilengitide (12.4 months/47%, 10.6 months/27%, and 11.6 months/36%, respectively). No clinically meaningful safety differences were observed between groups. None of the tested biomarkers (expression of integrins, CD31, Ki-67, vascular endothelial growth factor receptor 2, vascular endothelial-cadherin, type IV collagen, epidermal growth factor receptor, or p16 for human papillomavirus) were predictive of outcome. CONCLUSION: Neither of the cilengitide-containing regimens demonstrated a PFS benefit over PFE alone in R/M-SCCHN patients.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Cisplatino/uso terapêutico , Fluoruracila/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Venenos de Serpentes/uso terapêutico , Adulto , Idoso , Anticorpos Monoclonais Humanizados/efeitos adversos , Antimetabólitos Antineoplásicos/efeitos adversos , Antimetabólitos Antineoplásicos/uso terapêutico , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/análise , Cetuximab , Cisplatino/efeitos adversos , Progressão da Doença , Intervalo Livre de Doença , Receptores ErbB/antagonistas & inibidores , Feminino , Fluoruracila/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Venenos de Serpentes/efeitos adversos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Resultado do Tratamento
15.
Brain ; 136(Pt 2): 564-76, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23378223

RESUMO

Transforming growth factor-ß is a central mediator of the malignant phenotype of glioblastoma, the most common and malignant form of intrinsic brain tumours. Transforming growth factor-ß promotes invasiveness and angiogenesis, maintains cancer cell stemness and induces profound immunosuppression in the host. Integrins regulate cellular adhesion and transmit signals important for cell survival, proliferation, differentiation and motility, and may be involved in the activation of transforming growth factor-ß. We report that αvß3, αvß5 and αvß8 integrins are broadly expressed not only in glioblastoma blood vessels but also in tumour cells. Exposure to αv, ß3 or ß5 neutralizing antibodies, RNA interference-mediated integrin gene silencing or pharmacological integrin inhibition using the cyclic RGD peptide EMD 121974 (cilengitide) results in reduced phosphorylation of Smad2 in most glioma cell lines, including glioma-initiating cell lines and reduced transforming growth factor-ß-mediated reporter gene activity, coinciding with reduced transforming growth factor-ß protein levels in the supernatant. Time course experiments indicated that the loss of transforming growth factor-ß bioactivity due to integrin inhibition likely results from two distinct mechanisms: an early effect on activation of preformed inactive protein, and second, major effect on transforming growth factor-ß gene transcription as confirmed by decreased activity of the transforming growth factor-ß gene promoter and decreased transforming growth factor-ß(1) and transforming growth factor-ß(2) messenger RNA expression levels. In vivo, EMD 121974 (cilengitide), which is currently in late clinical development as an antiangiogenic agent in newly diagnosed glioblastoma, was a weak antagonist of pSmad2 phosphorylation. These results validate integrin inhibition as a promising strategy not only to inhibit angiogenesis, but also to block transforming growth factor-ß-controlled features of malignancy including invasiveness, stemness and immunosuppression in human glioblastoma.


Assuntos
Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Integrinas/fisiologia , Fator de Crescimento Transformador beta1/biossíntese , Animais , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Glioblastoma/tratamento farmacológico , Humanos , Integrinas/antagonistas & inibidores , Camundongos , Camundongos Nus , Vison , Vias Neurais/fisiologia , Venenos de Serpentes/farmacologia , Venenos de Serpentes/uso terapêutico , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Fator de Crescimento Transformador beta1/fisiologia
16.
Cochrane Database Syst Rev ; (9): CD008218, 2014 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-25242542

RESUMO

BACKGROUND: The most common primary brain tumours in adults are gliomas. Gliomas span a spectrum from low to high-grade and are graded pathologically on a scale of one to four according to the World Health Organization (WHO) classification. High-grade glioma (HGG) carries a poor prognosis. Grade IV glioma is known as glioblastoma (GBM) and carries a median survival in treated patients of about 15 months. GBMs are rich in blood vessels (i.e. highly vascular) and in a protein known as vascular endothelial growth factor (VEGF), which promotes new blood vessel formation (the process of angiogenesis). Antiangiogenic agents inhibit the process of new blood vessel formation and promote regression of existing vessels. Several antiangiogenic agents have been investigated in clinical trials in newly diagnosed and recurrent HGG, showing promising preliminary results. This review was undertaken to report on the benefits and harms associated with the use of antiangiogenic agents in the treatment of HGGs. OBJECTIVES: To evaluate the efficacy and toxicity of antiangiogenic therapy in patients with high-grade glioma. This intervention can be used in two broad groups of patients: those with first diagnosis as part of 'adjuvant' therapy, and those with recurrent or progressive disease. Comparisons will include the following.• Treatment with antiangiogenic therapy versus placebo.• Treatment (such as chemotherapy or chemoradiotherapy) with antiangiogenic therapy added versus the same treatment without the addition of antiangiogenic therapy. SEARCH METHODS: Searches were conducted to identify published and unpublished Randomised Controlled Trials (RCTs) starting in 2000; the following databases were searched: the Cochrane Central Register of Controlled Trials (CENTRAL), Issue 3, 2014; MEDLINE to April 2014 and EMBASE to April 2014. Proceedings of relevant oncology conferences since 2000 were handsearched. SELECTION CRITERIA: RCTs evaluating the use of antiangiogenic therapy versus control treatment without antiangiogenic therapy in the treatment of HGG. DATA COLLECTION AND ANALYSIS: Review authors screened the search results and reviewed the abstracts of potentially relevant articles before retrieving the full text of eligible articles. MAIN RESULTS: After a comprehensive literature search, seven eligible RCTs were identified (total of 2987 participants). Significant design heterogeneity was noted in the included studies, especially in the response assessment criteria used. All eligible studies were restricted to GBMs, and no eligible studies evaluated other HGGs. Four studies were available only in abstract form. We have reserved an overall assessment of the quality of the evidence until the final study publications are received. The three studies that have been published in full were judged to have low risk of bias. The seven trials of 2987 participants included in this systematic review did not show improvement in OS with the addition of antiangiogenic therapy (pooled hazard ratio (HR) 0.94, 95% confidence interval (CI) 0.86 to 1.02; P value 0.16). However, pooled analysis of PFS from six studies (2847 participants) showed improvement in PFS with the addition of antiangiogenic therapy (HR 0.74, 95% CI 0.68 to 0.81; P value < 0.00001). Bevacizumab was the antiangiogenic therapy more likely to yield favourable results. Pooled HR for PFS for bevacizumab studies (three studies with 1712 participants) was significant at 0.66 (95% CI 0.59 to 0.74; P value < 0.00001), and this was reflected in the lower hazard ratio reported in the pooled analysis of bevacizumab studies compared with the overall analysis. Nevertheless, this finding was not significant for OS (HR 0.92, 95% CI 0.83 to 1.02; P value 0.12). Similar to trials of antiangiogenic therapies in other solid tumours, adverse events related to this class of therapy included hypertension and proteinuria, poor wound healing and the potential for thromboembolic events, although generally, the occurrence of grade 3 events of this kind was low (< 14.1%), consistent with reported findings of studies of bevacizumab in other tumours. AUTHORS' CONCLUSIONS: In patients with newly diagnosed GBM, the use of antiangiogenic therapy does not improve survival, despite evidence of improved progression-free survival. Thus at this time, evidence is insufficient to support the use of antiangiogenic therapy in patients with newly diagnosed GBM on the basis of effects on survival.Bevacizumab may confer a progression-free survival benefit in GBM; however evidence in favour of using other antiangiogenic therapies in recurrent GBM is insufficient.Although bevacizumab appears to prolong progression-free survival in newly diagnosed and recurrent GBM, the impact of this on quality of life remains unclear.Adequately powered, randomised, placebo-controlled studies of bevacizumab in recurrent GBM (or HGG) are needed.Not addressed here is whether subsets of patients with newly diagnosed GBM may benefit from antiangiogenic therapies and whether these therapies are useful in other high-grade glioma histologies.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Neoplasias Encefálicas/irrigação sanguínea , Glioblastoma/irrigação sanguínea , Neovascularização Patológica/tratamento farmacológico , Inibidores da Angiogênese/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos/uso terapêutico , Bevacizumab , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/mortalidade , Camptotecina/análogos & derivados , Camptotecina/uso terapêutico , Dacarbazina/análogos & derivados , Dacarbazina/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/mortalidade , Humanos , Hipertensão/induzido quimicamente , Irinotecano , Lomustina/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Proteinúria/induzido quimicamente , Ensaios Clínicos Controlados Aleatórios como Assunto , Venenos de Serpentes/uso terapêutico , Temozolomida
17.
Cell Mol Life Sci ; 70(24): 4645-58, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23657358

RESUMO

Gram-positive and -negative bacteria are dangerous pathogens that may cause human infection diseases, especially due to the increasingly high prevalence of antibiotic resistance, which is becoming one of the most alarming clinical problems. In the search for novel antimicrobial compounds, snake venoms represent a rich source for such compounds, which are produced by specialized glands in the snake's jawbone. Several venom compounds have been used for antimicrobial effects. Among them are phospholipases A2, which hydrolyze phospholipids and could act on bacterial cell surfaces. Moreover, metalloproteinases and L-amino acid oxidases, which represent important enzyme classes with antimicrobial properties, are investigated in this study. Finally, antimicrobial peptides from multiple classes are also found in snake venoms and will be mentioned. All these molecules have demonstrated an interesting alternative for controlling microorganisms that are resistant to conventional antibiotics, contributing in medicine due to their differential mechanisms of action and versatility. In this review, snake venom antimicrobial compounds will be focused on, including their enormous biotechnological applications for drug development.


Assuntos
Anti-Infecciosos/uso terapêutico , Venenos de Serpentes/uso terapêutico , Animais , Anti-Infecciosos/química , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Humanos , L-Aminoácido Oxidase/química , L-Aminoácido Oxidase/uso terapêutico , Metaloproteases/química , Metaloproteases/uso terapêutico , Fosfolipases A2/química , Fosfolipases A2/uso terapêutico , Conformação Proteica , Venenos de Serpentes/química
18.
Eur Heart J ; 34(12): 886-893c, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22942338

RESUMO

Hypertension and heart failure (HF) are common diseases that, despite advances in medical therapy, continue to be associated with high morbidity and mortality. Therefore, innovative therapeutic strategies are needed. Inhibition of the neutral endopeptidase (NEPinh) had been investigated as a potential novel therapeutic approach because of its ability to increase the plasma concentrations of the natriuretic peptides (NPs). Indeed, the NPs have potent natriuretic and vasodilator properties, inhibit the activity of the renin-angiotensin-aldosterone system, lower sympathetic drive, and have antiproliferative and antihypertrophic effects. Such potentially beneficial effects can be theoretically achieved by the use of NEPinh. However, studies have shown that NEPinh alone does not result in clinically meaningful blood pressure-lowering actions. More recently, NEPinh has been used in combination with other cardiovascular agents, such as angiotensin-converting enzyme inhibitors, and antagonists of the angiotensin receptor. Another future possible combination would be the use of NEPinh with NPs or their newly developed chimeric peptides. This review summarizes the current knowledge of the use and effects of NEPinh alone or in combination with other therapeutic agents for the treatment of human cardiovascular disease such as HF and hypertension.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Inibidores Enzimáticos/uso terapêutico , Peptídeos Natriuréticos/metabolismo , Neprilisina/antagonistas & inibidores , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Doenças Cardiovasculares/enzimologia , Quimioterapia Combinada , Humanos , Peptídeos Natriuréticos/uso terapêutico , Piridinas/uso terapêutico , Venenos de Serpentes/uso terapêutico , Tiazepinas/uso terapêutico
19.
Chin J Cancer ; 33(1): 32-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24384238

RESUMO

Glioblastoma multiforme (GBM) is the most common malignant primary brain tumor in adults. Standard therapeutic approaches provide modest improvement in the progression-free and overall survival, necessitating the investigation of novel therapies. We review the standard treatment options for GBM and evaluate the results obtained in clinical trials for promising novel approaches, including the inhibition of angiogenesis, targeted approaches against molecular pathways, immunotherapies, and local treatment with low voltage electric fields.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Neoplasias Encefálicas/terapia , Glioblastoma/terapia , Imunoterapia , Adulto , Anticorpos Monoclonais Humanizados/uso terapêutico , Bevacizumab , Vacinas Anticâncer/uso terapêutico , Terapia por Estimulação Elétrica , Receptores ErbB/antagonistas & inibidores , Gefitinibe , Humanos , Quinazolinas/uso terapêutico , Venenos de Serpentes/uso terapêutico , Padrão de Cuidado , Vacinas de Subunidades Antigênicas/uso terapêutico
20.
Commun Biol ; 7(1): 358, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519650

RESUMO

Snakebite envenoming is an important public health issue responsible for mortality and severe morbidity. Where mortality is mainly caused by venom toxins that induce cardiovascular disturbances, neurotoxicity, and acute kidney injury, morbidity is caused by toxins that directly or indirectly destroy cells and degrade the extracellular matrix. These are referred to as 'tissue-damaging toxins' and have previously been classified in various ways, most of which are based on the tissues being affected (e.g., cardiotoxins, myotoxins). This categorisation, however, is primarily phenomenological and not mechanistic. In this review, we propose an alternative way of classifying cytotoxins based on their mechanistic effects rather than using a description that is organ- or tissue-based. The mechanisms of toxin-induced tissue damage and their clinical implications are discussed. This review contributes to our understanding of fundamental biological processes associated with snakebite envenoming, which may pave the way for a knowledge-based search for novel therapeutic options.


Assuntos
Mordeduras de Serpentes , Humanos , Mordeduras de Serpentes/tratamento farmacológico , Venenos de Serpentes/toxicidade , Venenos de Serpentes/uso terapêutico , Matriz Extracelular , Saúde Pública
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