Establishment of patient-derived tumor xenograft (PDTX) models using samples from CT-guided percutaneous biopsy

This study aimed to investigate the feasibility of the establishment of a human cancer xenograft model using samples from computed tomography (CT)-guided percutaneous biopsy. Fresh tumor tissues obtained from 10 cancer patients by CT-guided percutaneous biopsy were subcutaneously inoculated into NOD-Prkdcem26Il2rgem26Nju (NCG) mice to establish human patient-derived tumor xenograft (PDTX) models. The formation of first and second generation xenografts was observed, and tumor volume was recorded over time. Tumor tissue consistency between the PDTX model and primary tumors in patients was compared using H&E staining and immunohistochemistry. Pharmacodynamic tests of clinically used chemotherapeutic drugs were conducted on second generation xenografts, and their effects on tumor growth and body weight were observed. CT-guided percutaneous biopsy samples were successfully collected from 10 patients with advanced cancers. The PDTX model was established in mice using tumor samples obtained from 4 cancer patients, including one small cell carcinoma sample, two adenocarcinoma samples, and one squamous cell carcinoma sample. The success rate was 40%. The obtained PDTX model maintained a degree of differentiation, and morphological and structural characteristics were similar to primary tumors. The pharmacodynamic test of chemotherapeutic drugs in the PDTX model revealed a therapeutic effect on tumor growth, as expected. CT-guided percutaneous biopsy samples can be effectively used to establish a PDTX model, and test these chemotherapy regimens.

Experimental rat lung tumor model with intrabronchial tumor cell implantation

PURPOSE: The objective of this study was to develop a rat lung tumor model for anticancer drug testing. METHODS: Sixty-two female Wistar rats weighing 208 ± 20 g were anesthetized intraperitoneally with 2.5 percent 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 high-resolution computed tomography (HRCT) with findings from necropsia and determining time of survival. RESULTS: The tumor take rate was 94.7 percent 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 percent. 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.

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 tribromo-etanol 2,5 por cento IP (1ml/100g de rato), traqueostomizados e intubados com cateter ultrafino para injetar células do tumor de Walker. Na 1ª 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 2ª, 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 por cento. 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.

LYR71, a derivative of trimeric resveratrol, inhibits tumorigenesis by blocking STAT3-mediated matrix metalloproteinase 9 expression

Tumor migration/invasion is the main cause of tumor progression and STAT3 is needed to enhance tumor migration/invasion by up-regulating MMP-9. Thus, agents that inhibit STAT3 activation may be used as an anticancer drug. We present herein that 6-methyl-2-propylimino-6, 7-dihydro-5H-benzo [1, 3]-oxathiol- 4-one (LYR71) , a derivative of trimeric resveratrol, has an anticancer activity through inhibition of STAT3 activation. We found that LYR71 suppressed STAT3 activation and inhibited the expression and activity of MMP-9 in RANTES-stimulated breast cancer cells. In addition, LYR71 reduced RANTES-induced MMP-9 transcripts by blocking STAT3 recruitment, dissociating p300 and deacetylating histone H3 and H4 on the MMP-9 promoter. Furthermore, LYR71 inhibited tumor migration/invasion in RANTES-treated breast cancer cells and consequently blocked tumor progression in tumor-bearing mice. Taken together, the results of this study suggest that LYR71 can be therapeutically useful due to the inhibition effect of STAT3-mediated MMP-9 expression in breast cancer cells.

Antitumour effect of abrin on transplanted tumours in mice.

Abrin, a galactose specific lectin was purified using sepharose 4B affinity column from seeds of Abrus precatorius. It exhibited antitumour activity in mice when used at a sublethal dose of 7.5 micrograms/kg every alternate day for 10 days. Both intralesional and intraperiloneal (i.p.) administration of abrin was effective in reducing solid tumour mass development induced by Dalton's Lymphoma Ascites (DLA) and Ehrlich's Ascites Carcinoma (EAC) cells. DLA cell line was more sensitive to abrin than EAC. Abrin when injected i.p. increased the life span of ascites tumour bearing mice. Abrin when used simultaneously with tumour cells brought about maximum antitumour effect. On developed tumour masses, abrin administration brought about significant reduction in tumour volume, especially in DLA induced tumours. Prophylactic administration of abrin was found ineffective.