Novos complexos micelares de metais de transição para aplicação na terapia dirigida contra o cancro

O cancro é a segunda causa de mortalidade a nível mundial. Um dos problemas nos tratamentos atuais de quimioterapia relaciona-se com os efeitos secundários causados pela falta de seletividade dos fármacos utilizados. Assim, um dos desafios atuais é o desenvolvimento de sistemas terapêuticos que permitam potenciar o efeito dos fármacos e diminuir os seus efeitos nocivos. Neste contexto, neste trabalho, foram sintetizados complexos de Fe, Co e Zn com fórmula geral [M(bipy-R)3]x+, a partir dos quais foi possível obter sistemas micelares formados in situ pela adição de um copolímero de PLA-b-PEG ou por introdução de macroligandos poliméricos anfifílicos. Os resultados mostram que as nanopartículas formadas apresentam tamanho e características adequadas para aplicações na terapia dirigida contra o cancro. Os resultados preliminares de citotoxicidade na linha tumoral humana da mama MDAMB231 indicam que todos os compostos estudados apresentam atividade citotóxica relevante, sendo os compostos micelares os mais promissores; Abstract: New micellar transition metals complexes for targeted therapy of cancer Cancer is the second leading cause of mortality worldwide. One problem in the current chemotherapy treatments is related to the severe side effects caused by the lack of selectivity of the drugs in clinical use. Thus, one of the current challenges is the development of new therapeutic systems that allow maximizing the effect of the drugs and reducing their harmful effects. In this context, several Fe, Co and Zn compounds of the general formula [M (bipy-R)3]x+ were synthesized in order to obtain micellar systems, either by in situ addition of a PLA-b-PEG copolymer or by introducing amphiphilic macroligands. The results show that the formed nanoparticles have size and characteristics suitable for applications in targeted therapy against cancer. Preliminary results of cytotoxicity in human breast cancer line MDAMB231 indicate that all the studied compounds show significant cytotoxic activity, being the micellar compounds the most promising agents.

Clínica de animais de companhia

O presente relatório apresenta as atividades desenvolvidas no estágio decorrido no Hospital Ars Veterinaria. A primeira parte do relatório refere-se ao relatório de casuística com apresentação de casos e procedimentos acompanhados. A segunda refere-se à monografia com o tema “Opções terapêuticas em hemangiossarcoma canino” e encontra-se ilustrada por três casos clínicos. O hemangiossarcoma é uma neoplasia descrita com origem endotelial, devido à aparência histológica, no entanto descobertas recentes sugerem que provém de células progenitoras hematopoiéticas. Os sinais clínicos são inespecíficos e variáveis. A localização mais comum é o baço, embora ocorra noutras localizações. O diagnóstico requer o estadiamento tumoral e para ser completo deve incluir hematologia e bioquímica sérica, provas de coagulação, exames imagiológicos e confirmação histopatológica. O tratamento base é cirúrgico associado a protocolos quimioterápicos baseados em doxorrubicina. Novas terapias começam a ser investigadas de forma a melhorar os tempos de sobrevivência desta neoplasia de prognóstico reservado; Abstract: Small animal medicine This report was elaborated following a traineeship at the Ars Veterinaria Hospital. The first part concerns about cases report and includes presentation of cases and followed procedures. The second part is the monography under the theme “therapeutical options in canine hemangiosarcoma” and it presents three clinical cases seen during the internship. The hemangiossarcoma is a cancer described to have endothelial origin, because of its histological appearance, but recent discoveries suggest that it originates from hematopoietic progenitor cells. The clinical signs are variable and unspecific. The most common location is the spleen, but others might exist. The diagnosis demands tumoral staging, which to be complete must include hematology and biochemical analysis, coagulation tests, imagiologic tests and histopathologic confirmation. The basic treatment is surgical, associated with chemotherapy based on doxorubicin. New therapies are beginning to be investigated, aiming improve survival times of this cancer with reserved prognosis.

Anti-proliferative effects of novel hydroxyamides and triazoles

Chemotherapy is a major cancer treatment option. The synthesis of new compounds with anti-proliferative properties and specificity is a current challenge in drug-discovery today. Our goal was to develop compounds, either hydroxyamides derived from D-glucuronic acid or triazole-cinchone hybrids, and to evaluate their anti-proliferative properties. Anti-proliferative activity of the newly synthesized compounds was examined against human breast adenocarcinoma (MCF-7) and human colon carcinoma (MDST8) cell-lines. Cell growth and viability was analysed by the Cell-Counting Kit-8 method. The 5-fluoroacil was used as a positive control. The compounds were studied between 10-9-10-5M. Fifteen compounds from the hydroxyamide family and two triazole compounds were investigated. Most of the compounds from the hydroxyamide family revealed mild (~20%) to moderate (50%) anti-proliferative effects in both cell-lines, with the exception of Hydroxyamide B1 which did not affect MDST8 proliferation, and hydroxyamide B3 where proliferation of MDST8 was inhibited by 90%. Triazoles (A and B) evoked a strong (~100%) anti-proliferative effect of MDST8 cell-lines. Proliferation of MCF-7 was selectively and effectively (~98%) inhibited by triazole B while triazole A had a mild effect. In conclusion, when compared to hydroxyamides, triazoles evoked a stronger anti-proliferative effect and might be promising anti-tumoral drugs.