title: Characterization of gastric cancer models from different cell lines orthotopically constructed using improved implantation techniques.
abstract: OBJECTIVE
  To develop orthotopic gastric cancer mouse models from different cell lines and characterize the tumor features to assist further in preclinical trials and clinical treatment strategies.
  
  
  METHODS
  Human gastric cancer SGC-7901 and BGC-823 cell suspensions were injected subcutaneously into nude mice to develop solid tumors, and tumor tissue pieces were then implanted under the serous coat of the stomach. An autopsy was performed on all animals of the SGC-7901 and BGC-823 models to observe the primary tumor growth and metastases using pathological and immunohistochemical methods.
  
  
  RESULTS
  Both models showed large tumors in situ resulting in pressure and infiltration of the adjacent organs. The gastric cavity became smaller, along with stenosis of the cardia or pylorus. There were biological and statistical differences between the two models. The metastasis rate in involved organs (lymph nodes, kidney, spleen, testis) was significantly higher in the BGC-823 model compared to the SGC-7901 model (P < 0.05 or P < 0.01). The median survival of the BGC-823 model was shorter than that of SGC-7901 (23 d vs 84 d, P < 0.05). Histopathologically, the primary tumor and metastatic lesions of the two models showed obvious atypia and mucus in the cytoplasm. Compared with the SGC-7901 model, BGC-823 appeared more poorly differentiated (absence of adenoid structure), had a smaller volume, and richer capillary structure. Immunohistochemical staining revealed cytokeratin 20 and epithelial membrane antigen expression was positive in the SGC-7901 tumors, while negative in BGC-823 ones.
  
  
  CONCLUSIONS
  Models using the SGC-7901 and BGC-823 cell lines were established which could function in gastric cancer research on carcinogenesis mechanism and drug discovery. The two models showed different tumor behavior and the latter was more malignant than the former.
authors.affiliation: Department of Gastroenterology, the Second Affiliated Hospital, Chongqing Medical University, Chongqing 400010, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Bo
authors.initials: B
authors.lastname: Li
authors.forename: Chun-Ping
authors.initials: CP
authors.lastname: Xiang
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.forename: Yuan-Yuan
authors.initials: YY
authors.lastname: Li
authors.forename: Xiao-Ling
authors.initials: XL
authors.lastname: Wu
mesh_terms: D000818:Animals; D014408:Biomarkers, Tumor / Q000378:metabolism; D045744:Cell Line, Tumor; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D008875:Middle Aged; D009362:Neoplasm Metastasis / Q000473:pathology; D009368:Neoplasm Transplantation; D013270:Stomach / Q000473:pathology; D013274:Stomach Neoplasms / Q000473:pathology*; D015996:Survival Rate
chemical_list: D014408:Biomarkers, Tumor