Thesis (M. Phil.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 92-104). Also available in print.

nÃo hà / A vincristina à um quimioterÃpico e seu uso à limitado devido a neuropatia perifÃrica, com acometimento autonÃmico, sensitivo e motor. Sulfato de vincristina ou salina foram injetados na veia da cauda, nas doses de 50 Âg/Kg (5 doses), 100 Âg/Kg (2-5 doses) ou 150 Âg/Kg (1, 2 ou 5 doses) a cada dois dias em 144 ratos Wistar machos (200-250 g). No dia seguinte, os animais receberam a refeiÃÃo-teste por gavagem e foram sacrificados 10 minutos apÃs. A recuperaÃÃo gÃstrica e intestinal de corante foi determinada por espectrofotometria. ConstipaÃÃo foi avaliada pelo peso colÃnico e neuropatia sensitiva pela latÃncia tÃrmica (51Â0,5ÂC). PressÃo arterial mÃdia (PAM) e freqÃÃncia cardÃaca (FC) basais e valores da PAM e FC apÃs a administraÃÃo de fenilefrina 5 Âg/Kg e atropina 0,5 mg/Kg foram usados para estudo dos baroreflexos. DiferenÃas foram avaliadas por One-Way ANOVA com P<0,05. Tratamentos crÃnicos com 5 doses de 50 Âg/Kg; 3, 4 e 5 doses de 100 Âg/Kg; 2 e 5 doses de 150 Âg/Kg causaram retardo do esvaziamento gÃstrico (EG) (P<0,05). Duas e 5 doses de 150 Âg/kg induziram constipaÃÃo e houve reduÃÃo da latÃncia tÃrmica apÃs 1 dose de 50 Âg/Kg, 100 Âg/Kg e 150 Âg/kg (P<0,05). O efeito da vincristina sobre o EG nÃo foi evidenciado uma e duas semanas apÃs o tratamento com 5 doses de 150 Âg/Kg (P>0,05). Houve reduÃÃo do tempo de latÃncia ao calor por atà duas semanas apÃs 5 doses de 150 Âg/Kg (P<0,05). Vincristina potencializou a reduÃÃo da FC induzida pela fenilefrina e aumentou a resposta cardÃaca à atropina (P<0,05). A neuropatia autonÃmica induzida pela vincristina cursa com retardo do EG, alteraÃÃes na resposta baroreflexa e aumento do peso colÃnico. A neuropatia sensitiva precede o surgimento das alteraÃÃes autonÃmicas e persiste apÃs a reversÃo destas. / Vincristine is a chemotherapy drug and its use is limited by peripheral neuropathy with autonomic, sensory and motor involvement. Vincristine sulphate or saline was injected into the tail vein at doses of 50 Âg/Kg (5 doses), 100 Âg/Kg (2-5 doses) or 150 Âg/Kg (1, 2 or 5 doses) QOD in 144 male Wistar rats (200-250g). Next day, they were gavage-fed with a test meal and sacrificed 10 minutes later. Gastric and intestinal dye recovery was determined by spectrophotometry. Basal mean arterial pressure (MAP) and heart rate (HR) and peak values of MAP and HR after i.v. phenylephrine 5 Âg/Kg and atropine 0.5 mg/Kg were used to evaluate the baroreflex responses. Differences were evaluated by One-Way ANOVA with P<0.05. Chronic treatment with 5 doses of 50 Âg/Kg; 3, 4 and 5 doses of 100 Âg/Kg; 2 and 5 doses of 150 Âg/Kg delayed gastric emptying (GE) (P<0.05). Two and 5 doses of 150 Âg/Kg induced constipation and reduction in withdrawal latencies occurred after 1 dose of 50 Âg/Kg, 100 Âg/Kg and 150 Âg/Kg (P<0.05). Vincristine (150 Âg/Kg) immediately decreased fecal output (P<0.05). The effect of vincristine on the GE was not present in rats treated with 5 doses of vincristine 150 Âg/kg one week and two weeks after the last dose (P>0.05). The withdrawal latency decrease lasted for at least 2 weeks after 5 doses of 150 Âg/Kg (P<0.05). Vincristine enhanced the HR reduction induced by phenylephrine and enhanced cardiac response to atropine (P<0.05). Vincristine-induced autonomic neuropathy courses with delayed GE, altered baroreflex responses and increased colonic weight. Sensory neuropathy preceded and outlasted these autonomic changes.

Orientador: Konradin Metze / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-11T22:07:37Z (GMT). No. of bitstreams: 1 Scarpelli_KarimeCury_M.pdf: 4019689 bytes, checksum: 327500d1e9eaf9d7ba789fda03cc4064 (MD5) Previous issue date: 2008 / Mestrado / Ciencias Biomedicas / Mestre em Ciências Médicas

Les douleurs neuropathiques se caractérisent par l’apparition de symptômes positifs tels qu’une allodynie et de symptômes négatifs tel qu’une hypoalgésie. Les douleurs neuropathiques ont un retentissement important sur la qualité de vie et il n’existe à ce jour aucune thérapie efficace pour leur prise en charge préventive. Récemment, un système rénine-angiotensine tissulaire a été mis en évidence au sein du système nerveux périphérique sensitif et il a été démontré que sa modulation pharmacologique modifie la perception douloureuse chez l’animal. Dans ce travail, nous nous sommes intéressés à la physiopathologie et à la prévention thérapeutique des neuropathies sensitives par des modulateurs du SRA. Pour cela, deux modèles murins de neuropathie sensitive à l’origine de douleurs neuropathiques ont été utilisés ; un modèle de neuropathie induite par la résinifératoxine (RTX), toxine naturelle spécifique des petites fibres nociceptives et un modèle de neuropathie induite par la vincristine (VCR), un agent anticancéreux particulièrement neurotoxique. Une étude pharmacologique menée sur la neuropathie induite par la RTX nous a permis de mettre en évidence que seul le candésartan prévenait le développement de la neuropathie et que son effet était AT2R-dépendant. L’efficacité du candésartan a été confirmée dans le modèle de neuropathie chimio-induite, développé et caractérisé au cours de ce travail. Ce modèle de neuropathie induite par la VCR a permis de révéler, pour la première fois, le potentiel neuroprotecteur du C21 (agoniste direct du récepteur AT2R, Vicore Pharma) dans un contexte de neuropathie périphérique. L’ensemble de ces résultats confirme l’intérêt de la stimulation du récepteur AT2R dans le traitement des douleurs neuropathiques associées à une chimiothérapie, et plus largement d’origine toxique. / Neuropathic pain was characterized by positive symptoms as allodynia and negative symptoms as hypoalgesia. Neuropathic pain has a major impact on patient’s quality of life and there is, currently, no specific treatment for its preventive management. Recently, a specific renin angiotensin system in sensory peripheral nervous system has been showed and it has been demonstrated that its pharmacological modulation could modify pain perception in animals. In this work, we studied the neuroprotective potential of RAS modulators in two animal models of sensory neuropathy leading to neuropathic pain; a model of neuropathy induced by resiniferatoxin (RTX), a specific natural toxin of nociceptive nerve fibers, and a model of neuropathy induced by vincristine (VCR), a neurotoxic anticancer agent. Pharmacological study on mice with RTX-induced neuropathy allowed to conclude that only candesartan was neuroprotective and that its effect was AT2R-dependent.The effective neuroprotective effect of candesartan was confirmed on the model of VCR-induced neuropathy which was previously developed and characterized. This VCR-induced neuropathy mouse model allowed to demonstrate, for the first time, that C21 (a direct AT2R receptor agonist, Vicore Pharma) was neuroprotective against a peripheral neuropathy. All these results confirm the interest of stimulation of the AT2R receptor in the treatment of neuropathic pain associated with chemotherapy and more generally of toxic origin.

O estudo de agentes que interferem no funcionamento das proteínas relacionadas com o ciclo celular é importante para a compreensão dos processos de transformação e de morte celular. Alterações de ploidia, embora presentes na maioria dos tumores humanos, não têm ainda seu papel conhecido no processo de oncogênese. A alteração do número cromossômico é conseqüência primária de erros que envolvem o fuso mitótico e o cinetócoro. Dessa maneira, drogas que agem sobre os microtúbulos são consideradas aneugênicas potenciais. O presente trabalho enfocou o estudo do mecanismo pelo qual drogas que atuam sobre microtúbulos levam ao aparecimento de células multinucleadas e o significado biológico destas. Os resultados mostraram que a vincristina induziu bloqueio em mitose das células BBnt e MDCK, com conseqüente entrada em interfase no estado multinucleado. As células multinucleadas não apresentaram sinais de morte celular por apoptose, entretanto, quando em prófase apresentaram vários centrossomos, que poderiam originar divisões celulares com fusos multipolares. Estes resultados indicam que essas linhagens celulares possuem pontos de checagem mitótico funcionais e células multinucleadas são viáveis e capazes de prosseguir no ciclo celular. A presença de mitoses com fusos multipolares é indício de que as células multinucleadas passam por divisões anormais, que progrediriam para apoptose resultando na eliminação desta população. / The study of agents that interfere in the functionality of proteins related to cell cycle is important for the understanding of the transformation and cell death processes. Although ploidy alterations are presented in the majority of human tumors, their role in oncogenic process is not understood yet. The alteration on chromosomal number is the primary consequence of errors involving the mitotic spindle and kinetocore. Thus, drugs acting on the microtubules are considered as potentially aneugenic agents. The present work aimed to study the mechanism of multinucleated cells induction by action of antimicrotubule drug and biological meaning of these cells. The results showed that vincristine induced mitotic arrest of both BBnt and MDCK cells, with consequent entrance into interphasic-multinucleated status. Multinucleated cells did not present features of cell death by apoptosis; they were still viable and able to go further in cell-cycle progression. The presence of many structures suggested microtubule enucleation, centrosomes-like were detected on treated cells and could be responsible for the multi-spindle assembling that leads the multinucleated cells to abnormal divisions. Later on, when the multinucleated cells accumulated more abnormalities they were eliminated from the cell population by apoptosis.

O estudo de agentes que interferem no funcionamento das proteínas relacionadas com o ciclo celular é importante para a compreensão dos processos de transformação e de morte celular. Alterações de ploidia, embora presentes na maioria dos tumores humanos, não têm ainda seu papel conhecido no processo de oncogênese. A alteração do número cromossômico é conseqüência primária de erros que envolvem o fuso mitótico e o cinetócoro. Dessa maneira, drogas que agem sobre os microtúbulos são consideradas aneugênicas potenciais. O presente trabalho enfocou o estudo do mecanismo pelo qual drogas que atuam sobre microtúbulos levam ao aparecimento de células multinucleadas e o significado biológico destas. Os resultados mostraram que a vincristina induziu bloqueio em mitose das células BBnt e MDCK, com conseqüente entrada em interfase no estado multinucleado. As células multinucleadas não apresentaram sinais de morte celular por apoptose, entretanto, quando em prófase apresentaram vários centrossomos, que poderiam originar divisões celulares com fusos multipolares. Estes resultados indicam que essas linhagens celulares possuem pontos de checagem mitótico funcionais e células multinucleadas são viáveis e capazes de prosseguir no ciclo celular. A presença de mitoses com fusos multipolares é indício de que as células multinucleadas passam por divisões anormais, que progrediriam para apoptose resultando na eliminação desta população. / The study of agents that interfere in the functionality of proteins related to cell cycle is important for the understanding of the transformation and cell death processes. Although ploidy alterations are presented in the majority of human tumors, their role in oncogenic process is not understood yet. The alteration on chromosomal number is the primary consequence of errors involving the mitotic spindle and kinetocore. Thus, drugs acting on the microtubules are considered as potentially aneugenic agents. The present work aimed to study the mechanism of multinucleated cells induction by action of antimicrotubule drug and biological meaning of these cells. The results showed that vincristine induced mitotic arrest of both BBnt and MDCK cells, with consequent entrance into interphasic-multinucleated status. Multinucleated cells did not present features of cell death by apoptosis; they were still viable and able to go further in cell-cycle progression. The presence of many structures suggested microtubule enucleation, centrosomes-like were detected on treated cells and could be responsible for the multi-spindle assembling that leads the multinucleated cells to abnormal divisions. Later on, when the multinucleated cells accumulated more abnormalities they were eliminated from the cell population by apoptosis.

Background: Peripheral neuropathy is a common treatment-related adverse effect associated with vincristine. Vincristine is a major CYP3A4 substrate and is often administered alongside the neurokinin-1 (NK-1) receptor antagonists, aprepitant or fosaprepitant, which are moderate CYP3A4 inhibitors. This inhibition may result in increased concentrations of vincristine and an increased incidence of toxicity. Objective:The primary objective of this study was to investigate if there is a clinically significant drug interaction between vincristine and aprepitant or fosaprepitant resulting in early-onset peripheral neuropathy. The secondary objective of this study was to investigate the cumulative rate of chemotherapy-induced peripheral neuropathy (CIPN). Methodology:This was a single-centered, retrospective, cohort chart review. Patients receiving vincristine-based chemotherapy between 1 July 2010 through 30 June 2018 were identified and reviewed for concomitant use of aprepitant or fosaprepitant and incidence of neuropathy. Early-onset CIPN was defined as neuropathy onset during the first cycle of chemotherapy. Results:A total of 115 subjects were retrospectively reviewed over the study period, of whom 71 were included in the aprepitant/fosaprepitant group and 44 were included in the group without a NK-1 receptor antagonist. Of the subjects who received aprepitant/fosaprepitant, 26.7% experienced early-onset peripheral neuropathy as compared to 22.7% in the group without a NK-1 receptor antagonist (P = 0.627). Overall, CIPN was higher in the group who received aprepitant/fosaprepitant compared to the group without (56% vs. 36%, P = 0.036). Conclusion:There appears to be an increased risk of CIPN with the concomitant use of vincristine and aprepitant or fosaprepitant.

Drug-induced pancreatitis is a condition characterized by sudden inflammation of the pancreas that can be mild or severe but usually subsides. Signs and symptoms consist of abdominal pain, nausea/vomiting, low-grade fever and pain radiating to the lower back. The incidence of acute drug-induced pancreatitis is approximately 2% but in patients that have disease states that predispose them to the development of pancreatitis, such as malignancy, hypercalcemia, tumor lysis syndrome, and immunosuppression it is found to be much higher. Conditions that should be considered in the differential diagnosis are cholelithiasis, hyperlipidemia, pancreatic tumor and alcoholism. Additionally, several medications have been reported to have an association with inducing pancreatitis. The focused medications are cyclophosphamide, vincristine and prednisone. All three of these drugs come with a probable association of medications that can induce pancreatitis. Having risk factors and potential drugs that could induce pancreatitis make it challenging to pinpoint the cause. A 79-year-old male presented to the hospital with generalized weakness and altered mental status lasting approximately 5 days. A clinical diagnosis of angioimmunoblastic T-cell lymphoma was made and chemotherapy was started during the stay. CVP (cyclophosphamide, vincristine, and prednisone) chemotherapy was given along with a rasburicase for potential tumor lysis syndrome. All labs were within normal limits prior to chemotherapy except for calcium, which was 10.9mg/dL and 12.42mg/dL after correction for the albumin being 2.1gm/dL. The following day the patient complained of severe abdominal pain and had mild abdominal distention. A diagnosis of pancreatitis was made after labs revealed: amylase >600 U/L, corrected calcium 12.04mg/dL, glucose 260mg/dL, a bump in BUN from 34 to 50mg/dL and a normal lipid panel. The patient also had a CT scan that revealed cholelithiasis. Subsequently the chemotherapy was stopped and normal saline was given at 50mL/hr due to his heart failure with reduced ejection fraction. Upon discontinuation of the chemotherapy, the patients abdominal pain resolved within 2 days and labs started to return to normal. Labs revealed: corrected calcium 10.5mg/dL, glucose 98mg/dL and BUN 40mg/dL. The chemotherapy agent was switched to intrathecal methotrexate, in which the patient had no trouble tolerating and the abdominal pain never returned. Ultimately, the patient developed worsening heart failure and 20 days later expired. The complexity of pinpointing conditions, risk factors, or drug causes for pancreatitis is outlined in this case. This patient had several risk factors for developing pancreatitis such as malignancy and hypercalcemia but didn’t have any signs/symptoms. After CVP chemotherapy was started, the signs/symptoms matched the labs and clinical diagnosis but cholelithiasis revealed. Once the chemotherapy was stopped all signs/symptoms subsided and labs returned to normal. The most likely cause was the chemotherapy due to the timeline from initiation of therapy to the onset of pancreatitis symptoms but this case is extremely complex due to other conditions and risk factors.

O Sarcoma de Ewing (ES) é um raro tumor de ossos e tecidos moles com uma característica translocação cromossomal, a fusão EWS/FLI-1, que atua sobre diversos processos oncogênicos. O desenvolvimento da resistência à quimioterapia é comum no tumor e continua como uma das principais causas na falha do tratamento. O objetivo desse estudo foi avaliar a expressão de genes após a indução de resistência em linhagens celulares de ES. Foi selecionado um conjunto de genes (CCAR1, TUBA1A, POLDIP2, SMARCA4 e SMARCB1) a partir da mineração da literatura em resistência tumoral para duas drogas utilizadas na terapia de ES, doxorrubicina e vincristina. Descrevemos a expressão de cada gene selecionado antes e após as linhagens SK-ES-1 serem submetidas a um protocolo de indução de resistência para ambos os fármacos, que obteve êxito ao induzir as células à resistência. A expressão relativa dos níveis de mRNA foi avaliada e foi encontrada em maior expressão para os genes SMARCA4, SMARCB1 e POLDIP2, e em menor expressão para os genes TUBA1A e CCAR1, quando comparadas às linhagens de controle não-resistentes de cada quimioterápico. Os resultados sugerem o envolvimento de mecanismos de reparo de dano ao DNA, remodelamento de cromatina via SWI/SNF, atividade de microtúbulos e atividade spliceossomal nos processos de resistência quimioterápica em ES. / Ewing Sarcoma (ES) is a rare bone and soft tissue tumor with a characteristic chromosomal translocation, the fusion protein EWS/FLI-1, that drives several oncogenic processes. The development of resistance to chemotherapy is common and remains as the main cause of treatment failure. The goal of this study was to evaluate the expression of selected genes in ES cell lines after induction of resistance. A set of genes (CCAR1, TUBA1A, POLDIP2, SMARCA4 and SMARCB1) was data mined from tumoral resistance literature for two drugs used in ES therapy, doxorubicin and vincristine. We describe the expression of each selected gene before and after SK-ES-1 cell lines were exposed to a drug resistance inducing protocol for doxorubicin and vincristine. Cell lines were successfully induced to be resistant to doxorubicin and vincristine. The relative mRNA expression levels were upregulated for genes SMARCA4, SMARCB1 and POLDIP2 and downregulated for genes TUBA1A and CCAR1, when comparing resistant and non-resistant ES cell lines for each drug. The results suggest involvement of repair pathways, SWI/SNF chromatin remodeling, microtubule and spliceosomal activity processes in drug resistance mechanisms in ES.

Orientador: Noeme Sousa Rocha / Resumo: O tumor venéreo transmissível canino (TVTC) ocorre naturalmente em cães, sem predileção por raça ou sexo sendo transmitido durante o coito ou hábitos sociais. É também um tumor transplantável experimentalmente e tem sido utilizado como modelo para o estudo da relação entre tumor e hospedeiro. Apesar da maior infiltração inflamatória intratumoral e da expressão de moléculas do complexo principal de histocompatibilidade (MHC) estar associada à regressão do tumor, o papel central das células imunes do hospedeiro na evolução clínica do TVTC ainda não está claro. Neste estudo nós buscamos analisar a interação entre TVTC natural e hospedeiro, especialmente sob o ponto de vista da imunidade celular tumoral. Aqui nós identificamos e quantificamos por citometria de fluxo células T (CD3+, CD4+ e CD8+), células NK, células B, macrófagos, em amostras de sangue e de tumor, além da expressão imunoistoquímica de moléculas do MHC de classe I e II, sobretudo nas diferentes fases clínicas do tumor, assim como classificamos os subtipos citológicos do tumor e avaliamos o comportamento tumoral frente ao tratamento quimioterápico com sulfato de vincristina em uma amostra de 22 cães com TVTC natural. A quimioterapia foi efetiva no tratamento da maioria dos casos. Encontramos predomínio de TVTC linfocitóide e que metástases e resistência quimioterápica ocorreram apenas nos tumores de fenótipo linfocitóide e misto. Identificamos aumento significativo na expressão de moléculas de MHC classe I e II na ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The transmissible venereal canine tumor (CTVT) occurs naturally in dogs, without predilection for race or gender being transmitted during intercourse or social habits. It is also an experimentally transplantable tumor and it has been used as a pattern for the study about the relationship between the tumor and the host. Despite the greater intratumoral inflammatory infiltration and the expression of major histocompatibility complex molecules (MHC) is associated with tumor regression, the central role of host immune cells in the CTVT clinical evolution is not clear yet. In this study we sought to analyze the interaction between natural and host CTVT, especially from the point of view of tumor cell immunity. Here we identify and quantify by flow cytometry cells T (CD3+, CD4+ e CD8+), cells NK, cells B, macrophages, in blood and tumor samples, besides the immune histochemical expression of MHC class I and II molecules, specially in the different clinical phases of the tumor as well as classifying the cytological subtypes of the tumor and evaluating the tumor behavior against the chemotherapy treatment with vincristine sulfate in a sample of 22 dogs with natural CTVT. Chemotherapy was effective in the treatment of most cases. We found a predominance of lymphocytoid CTVT and that metastases and chemotherapeutic resistance occurred only in tumors of lymphocytoid and mixed phenotype. We identified a significant increase in the expression of MHC class I and II molecules in the regress... (Complete abstract click electronic access below) / Mestre