胃癌细胞株MKN-45裸鼠移植瘤模型的建立与应用

Establishment and application of gastric cancer cell strain MKN-45 xenograft model of nude mice

目的建立低分化高转移性胃癌细胞株MKN-45裸鼠移植瘤模型,并观察该移植瘤对抗癌药物的敏感性。方法 5×106个MKN-45胃癌细胞接种于裸鼠右侧胁部脂肪垫下,观察成瘤情况。接种2周后,分别将荷瘤小鼠分为生理盐水对照组与化疗药物组,其中化疗药物组给予1 mg·kg-1紫杉醇与5 mg·kg-1氟尿嘧啶,1周1次,连续3周;生理盐水对照组则给予生理盐水。实验结束后采用HE染色观察移植瘤病理组织学特点,采用免疫组化法检测移植瘤的核增殖抗原Ki-67与波形蛋白(vim-entin)及钙黏蛋白(E-cadherin)表达情况。结果接种的12只裸鼠均荷瘤成功,且移植瘤成瘤时间早,肿瘤大小及形状较一致,并保持了原发肿瘤vimentin高表达与E-cadherin低表达等重要的生物学特征。使用临床抗癌药物紫杉醇与氟尿嘧啶联合处理3周,结果与生理盐水对照组相比,化疗组肿瘤生长速度明显放缓,肿瘤体积明显缩小,肿瘤组织Ki-67表达下降,新生血管减少,肿瘤细胞凋亡明显,但vimentin与E-cadherin表达变化不明显。结论胃癌细胞株MKN-45裸鼠移植瘤模型建立成功,为开展胃癌发病机制及治疗药物药理作用等研究提供了理想的实验平台。

Objective To establish an ideal nude mice model bearing gastric cancer cell line MKN-45,and to observe the sensitivity of the xenograft for anti-cancer drugs.Methods Nude mice were injected with 5 × 106 MKN-45 gastric cancer cells in the right flank fat pad.The tumor growth and histopathological features were observed,and the expression of Ki-67,E-cadherin and vimentin of tumor were detected by immunohistochemistry.After tumor cell inoculation for two weeks,tumor-bearing mice were divided into chemotherapy medication group with 1 mg.kg-1 paclitaxel combined 5 mg.kg-1 fluorouracil and control group with saline（n = 6）.The drugs were given once per week for consecutive three weeks.Tumor growth and pathological changes were compared between two groups.Results Inoculated 12 mice were successfully tumor-bearing,and had an early tumor-forming time and consistent tumor size and shape,and keep the important biological characteristics of primary tumor with high-expression vimentin and low-expression E-cadherin.After clinical anti-cancer drug paclitaxel and fluorouracil combined treatment for three weeks,compared with control group,the tumor growth was slowing down,tumor volume was significantly inhibited,Ki-67 expression and neovascularization reduced and cell apoptosis increased in chemotherapy group.However,the expression of vimentin and E-cadherin did not change significantly between two groups.Conclusion The nude mice model bearing gastric cancer cell line MKN-45 is successfully established,which provides an ideal tool for the research of gastric cancer pathogenesis and anti-cancer therapeutic pharmacology.