Banca de DEFESA: CAROLINA ALVES PETIT COUTO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : CAROLINA ALVES PETIT COUTO
DATE: 17/08/2023
TIME: 13:30
LOCAL: google meet
TITLE:

Biodistribution, antitumor activity and toxicity of Methotrexate and etoposide-carrying polymeric nanomicelles 

KEY WORDS:

Cancer, nanocarriers, therapeutic combination, drug delivery

PAGES: 30
BIG AREA: Ciências Biológicas
AREA: Bioquímica
SUMMARY:

The use of nanocarriers makes it possible to distribute the drug in the target tissue, causing adverse effects, including for therapeutic combinations between drugs of different bioavailability. In addition, it helps in the prolonged circulation time of the drug and in its controlled and sustained release. Methotrexate and etoposide-carrying polymeric nanomicelles (NPME) were previously tested and with promising in vitro results. The objectives of this work are to evaluate (i) NCS1 protein expression after treatment with NPME, (ii) cytotoxicity of NPME in spheroid models, (iii) biodistribution, toxicity and antitumor activity of NPME in mice from tumor and compare these effects of NPME with free unloaded drugs. A western blot assay was performed for proteins from 4T1luc cells and showed that this cell line has the expression of NCS1, a protein related to cell invasion and metastasis. The expression of NCS1 after treatment with NPME is already being evaluated. For the spheroid model, 3D cultivation of 4T1luc cells in 2% agarose was performed. These were treated with NPME (110 and 250 µg/mL) for 6 hours and then fed for lactate dehydrogenase release. Although these concentrations were able to significantly decrease the viability of 4T1luc cells in the monolayer (previous results), they did not cause toxicity in the spheroids, probably due to the difficulty of diffusion and diffusion of NPME. For biodistribution, as NPME, methotrexate (MTX) and etoposide (ETO) were radiolabelled with technetium, showing purity of 95.4%, 62.7% and 77.7% respectively. The stability of the radiolabelling was evaluated in vivo in healthy animals, which received intravenously NPME or each of the free radiolabeled drugs. The scintigraphic images were acquired 30 minutes, 4 and 7 hours after the intravenous injection and found what was expected in the liver, kidneys and lung. Furthermore, the thyroid did not show radioactivity, which indicates that the technetium did not release from the NPME or the drugs, confirming the stability of the radiolabeling. Having confirmed the efficiency and stability of the labeling, 18 animals were subcutaneously inoculated with 4T1luc cells. The tumor is in the development phase so that the biodistribution of free and nanocarried drugs can be evaluated by acquisition of scintigraphic images and radioactive counting of the organs. Regarding in vivo antitumor activity, a pilot experiment is being controlled in 18 animals with subcutaneous tumor of 4T1luc, which are receiving different concentrations of NPME and will be collected for evaluation of its size and histology. Once the best concentration is defined, the in vivo antitumor assay will be repeated for comparison with the free drugs injected at the corresponding concentrations and also to evaluate the toxicity of the treatments (hemogram, liver and kidney functions, histological analysis of the organs).

BANKING MEMBERS:
Interna - 1971926 - NAYARA DELGADO ANDRE BORTOLETO
Externo ao Programa - 2255060 - IGOR JOSE BOGGIONE SANTOS
Externo ao Programa - 1526269 - LEANDRO AUGUSTO DE OLIVEIRA BARBOSA
Externo à Instituição - ANDRE LUIS MORAIS RUELA - UFOP
Externa à Instituição - GISELE RODRIGUES DA SILVA - UFOP
Externo à Instituição - ORLANDO DAVID HENRIQUE DOS SANTOS - UFOP