Establishment and identification of an orthotopic transplanted model of gastric carcinoma with peritoneal carcinomatosis in nude mice

Abstract

Objective To establish an orthotopic transplanted model of gastric cancer with peritoneal carcinomatosis in nude mice and identify the pathological features of the model.Methods The homogenate of MGC-803 gastric cancer tissue was planted in gastric antrum of 11 BALB/c nude mice to establish the model of gastric cancer with peritoneal carcinomatosis.The general status was recorded.The routine morphological examination and immunohistochemistry were performed to detect tumor biological features related to proliferation,apoptosis,invasion and metastasis [B lymphocytes/leukemia-2 (bcl-2),bcl-6,Ki-67,TdT-mediated dUTP nick end labeling (TUNEL),vascular endothelial growth factor (VEGF),matrix metalloproteinase (MMP)-9,CD34,and D2-40].Results The animal models were constructed successfully (11/11).The body weight of nude mice was slowly increased during the model development.The orthotopic tumor weight was (210.5-379.0) mg (median 267.5 mg).Cancer cell heterogeneity,and microvascular/lymphatic tumor thrombus were obviously observed as well as perigastric lymph nodes and liver metastases.Tumor proliferation-related molecule detection showed that bcl-2 positive rate was 0.0％-10.4％ (median 3.3％),bcl-6 positive rate was 0.0％-11.1％ (median 3.3％),Ki-67 positive rate was 40.5％-48.6％ (median 45.4％),and TUNEL positive rate was 0.2％-3.1％ (median 0.9％).The number of tumor blood vessels marked with CD34 was 1-11 (median 3)/400 × field of vision.The number of lymphatics marked with D2-40 was 0-5 (median 2)/400 × field of vision.VEGF positive rate was 68.5％-95.8％ (median 82.4％),and MMP-9 positive rate was 13.5％-50.0％ (median 23.5％).Conclusion The orthotopic transplanted model of gastric cancer with peritoneal carcinomatosis in nude mice was successfully established and reproduced the typical features of poorly differentiated adenocarcinoma. Key words: Gastric cancer; Peritoneal metastasis; Orthotopic transplantation; Model, animal