Submitted by Sara Ribeiro (sara.ribeiro@ucb.br) on 2017-09-06T18:13:45Z No. of bitstreams: 1 JordanBarrosdaSilvaDissertacao2017.pdf: 2923625 bytes, checksum: f4397cfc3ec64b731e5825c3fd8ad2cb (MD5) / Approved for entry into archive by Sara Ribeiro (sara.ribeiro@ucb.br) on 2017-09-06T18:15:05Z (GMT) No. of bitstreams: 1 JordanBarrosdaSilvaDissertacao2017.pdf: 2923625 bytes, checksum: f4397cfc3ec64b731e5825c3fd8ad2cb (MD5) / Made available in DSpace on 2017-09-06T18:15:05Z (GMT). No. of bitstreams: 1 JordanBarrosdaSilvaDissertacao2017.pdf: 2923625 bytes, checksum: f4397cfc3ec64b731e5825c3fd8ad2cb (MD5) Previous issue date: 2017-03-14 / UCB / Myelofibrosis (MF) is a rare disease that has an annual incidence of 1 in every 100,000 inhabitants in world, with an average survival of 69 months after diagnosis. Patients with MF have a delicate prognosis and common findings are increased platelet and erythrocyte counts, extramedullary hematopoiesis, hepatomegaly and splenomegaly, and medullary fibrosis. In recent years, several mutations have been reported in the literature, such as JAK2V617F, CalR and MPL, however, the only commercialized therapy so far (Ruxolitinib) has no curative potential. Extracellular vesicles (EVs) comprise a group of vesicles with a size of approximately 30 to 1000 nm and can carry molecules such as lipids, proteins and RNAs inside them. Due to these characteristics, several recent studies have demonstrated a relationship between the EVs and several types of clonal diseases, where patients with malignancies presented high levels of EV in the serum. Among the RNAs found the interior of the EVs, miRNAs are differentially expressed, since it is known that the small molecules are involved in several cellular processes. The present study has as a characteristic the trace of an EV profiles in patients with Myelofibrosis accompanied at the Hematology and Hemotherapy Unit of the Federal District Base Hospital, as well as a differential expression of the microRNAs miR-29a-3p, miR-155 -5p and miR-223-3p and correlate with the clinical features of the disease. The data show that miR-29a and miR-155 are differentially expressed in MF patients, both of which are downregulated. The miR-223 did not present significant differences. Knowing that the low expression of miR29a is related to an aberrant self-renewal of hematopoietic progenitor cells, the data presented here indicate that the EV may contribute to the pathophysiology of the disease. / A Mielofibrose (MF) ?? uma doen??a rara que possui incid??ncia anual de 1 em cada 100.000 habitantes no mundo, com m??dia de sobrevida de 69 meses ap??s o diagn??stico. Os pacientes com MF geralmente apresentam progn??stico delicado e os achados comuns s??o aumento na contagem plaquet??ria e eritrocit??ria, hematopoiese extramedular, hepatomegalia e esplenomegalia e fibrose medular. Nos ??ltimos anos, v??rias muta????es foram relatadas na literatura, como a JAK2V617F, a CalR e MPL, no entanto, a ??nica terapia comercializada at?? o momento (Ruxolitinib) n??o possui potencial curativo. Ves??culas Extracelulares (VEs) compreendem um grupo de ves??culas com tamanho aproximado de 30 a 1000 nm e podem transportar em seu interior mol??culas como lip??dios, prote??nas citos??licas e RNAs. Devido a essas caracter??sticas, v??rios estudos recentes v??m demonstrando a rela????o entre as VEs e diversos tipos de doen??as clonais, onde os pacientes portadores dessas malignidades apresentaram n??veis elevados de VEs no soro. Dentre os RNAs encontrados no interior das VEs, destacam-se os miRNAs diferencialmente expressos, pois sabe-se que essas pequenas mol??culas est??o envolvidas em diversos processos celulares. O presente estudo se prop??s a caracterizar e tra??ar um perfil das VEs em pacientes portadores de Mielofibrose acompanhados na Unidade de Hematologia e Hemoterapia do Hospital de Base do Distrito Federal, bem como avaliar a express??o diferencial dos microRNAs miR-29a-3p, miR-155-5p e miR-223-3p e correlacionar com as caracter??sticas cl??nicas da doen??a. Os dados encontrados mostram que o miR-29a e o miR-155 se apresentam diferencialmente expresso nos pacientes com MF, sendo ambos pouco expressos. O miR-223 n??o apresentou diferen??as significativas. Sabendo que a baixa express??o do miR29a est?? relacionada a uma auto renova????o aberrante de c??lulas progenitoras hematopoi??ticas, os dados aqui apresentados indicam que as VEs podem contribuir com fisiopatologia da doen??a.