Experimental rat lung tumor model with intrabronchial tumor cell implantation

Abstract

Purpose: The objective of this study was to develop a rat lung tumor model for anticancer drug testing. Methods: Sixtytwo female Wistar rats weighing 208 ± 20 g were anesthetized intraperitoneally with 2.5% tribromoethanol (1 ml/100 g live weight), tracheotomized and intubated with an ultrafine catheter for inoculation with Walker's tumor cells. In the first step of the experiment, a technique was established for intrabronchial implantation of 10 5 to 5×10 5 tumor cells, and the tumor take rate was determined. The second stage consisted of determining tumor volume, correlating findings from highresolution computed tomography (HRCT) with findings from necropsia and determining time of survival. Results: The tumor take rate was 94.7% for implants with 4×10 5 tumor cells, HRCT and necropsia findings matched closely (r=0.953; p<0.0001), the median time of survival was 11 days, and surgical mortality was 4.8%. Conclusion: The present rat lung tumor model was shown to be feasible: the take rate was high, surgical mortality was negligible and the procedure was simple to perform and easily reproduced. HRCT was found to be a highly accurate tool for tumor diagnosis, localization and measurement and may be recommended for monitoring tumor growth in this model.Key words: Lung neoplasms; Walker-256 carcinoma; rats. RESUMO Objetivo: O objetivo foi desenvolver um modelo de tumor de pulmão em rato que permita o teste de fármacos no tratamento deste câncer. Métodos: Sessenta e dois ratos Wistar fêmeas, peso médio de 208±20 g, foram anestesiados com tribromoetanol 2,5% IP (1ml/100g de rato), traqueostomizados e intubados com cateter ultrafino para injetar células do tumor de Walker. Na 1 a etapa, estabeleceu-se a técnica do implante de células tumorais por via intrabrônquica e o índice de pega tumoral, usando-se de 10 5 a 5×10 5 células. Na 2 a , avaliou-se o volume tumoral e a correlação dos achados obtidos na tomografia computadorizada de alta resolução (TCAR) de tórax com os da necropsia e verificou-se a sobrevida. Resultados: O índice de pega foi de 94,7, com o implante de 4×10 5 células do tumor; as medidas do tumor feitas na TCAR e comparadas com as da necropsia foram semelhantes (r=0, 953, p<0,0001); a sobrevida mediana foi de 11 dias; e a mortalidade cirúrgica de 4,8 %. Conclusão: O modelo mostrou-se viável, com alto índice de pega, mortalidade cirúrgica desprezível, de execução simples e fácil reprodutibilidade. A TCAR revelou alta acurácia no diagnóstico, localização e mensuração das lesões tumorais, credenciando-se para a monitorização de crescimento tumoral nesse modelo.Descritores: Neoplasias Pulmonares; Carcinoma 256 de Walker; Ratos.

The AIB1siRNA-loaded hyaluronic acid-assembled PEI/heparin/Ca2+ nanocomplex as a novel therapeutic strategy in lung cancer treatment

“…Lung cancer is one of the leading causes of cancer-related death in both men and women, worldwide (1). Histologically, two different types of lung cancer exist, which are classified based on their microscopic appearance (2).…”