乳腺癌淋巴结转移动物模型的建立及评价

Establishment and evaluation of an animal model for lymph node metastasis of breast cancer

目的建立不同乳腺癌淋巴结转移的动物模型,并评价其效果。方法取6~8周龄BALB/c雌性小鼠60只,采用4T1乳腺癌细胞悬液注射小鼠不同部位等人工移植方法构建6种淋巴结转移动物模型(n=10),另采用小鼠乳腺肿瘤病毒介导多瘤病毒中间T抗原(mouse mammary tumor virus-polyoma middle T antigen,MMTV-PyMT)转基因小鼠作为肿瘤自发淋巴结转移模型(n=5),并从操作可行性、病理组织学观测、肿瘤生长速度及小鼠生存等多方面综合评价不同淋巴结转移模型的优劣特征。结果7种转移模型方法中有4种成功建立淋巴结转移的动物模型,其中PyMT小鼠自发淋巴结转移模型临床复现情况最佳,成瘤率可达100%,但存在实验标准化差的弊端;后脚掌-腘窝淋巴结模型淋巴结发生转移速度最快,易操作且重复性高,成瘤率也可达100%,适合用于淋巴结转移相关研究;腿部-腹股沟淋巴结模型操作简单,重复率高,可达100%,但是其转移时间较后脚掌-腘窝淋巴结模型略长;腹股沟淋巴结-对侧淋巴结模型存在操作较难、荷瘤成功率仅为50%、重复性差的缺陷;另外3种荷瘤模型(舌下-颈内静脉肩胛舌骨肌淋巴结模型、骨髓内-腹股沟淋巴结模型及右上背皮-腋窝淋巴结模型)均未能在短时间内成功建立淋巴结转移模型,在病理切片中未观察到肿瘤细胞的存在。结论后脚掌-腘窝淋巴结模型成瘤效果好,最适合用于开展乳腺癌淋巴结转移相关研究。

Objective To establish an animal model and evaluation system for lymph node metastasis of breast cancer.Methods A total of 60 female BALB/c mice(6~8 weeks old)were subjected,and then 6 models of lymph node metastasis(n=10)were constructed through injection at different parts in the mice with cell suspension of 4T1 breast cancer cells.Transgenic mice(n=5)of mouse mammary tumor virus-polyoma middle T antigen(MMTV-PyMT)were employed and served as model of spontaneous tumor metastasis.Then the advantages and disadvantages of different lymph node metastasis models were comprehensively evaluated from multiple aspects,such as operability,histomorphology and pathological detection,tumor growth rate and mouse survival.Results Among the 7 metastasis models,4 models of lymph node metastasis were successfully established.Among them,the PyMT mouse spontaneous tumorigenesis model showed the best clinical reproduction,with a tumorigenesis rate of up to 100%,but had a disadvantage of poor experimental standardization.The hind paw-popliteal lymph node model had the fastest lymph node metastasis,easy operation and high repeatability,and a tumorigenesis rate of 100%,indicating its suitable for lymph node metastasis related research.The thigh subcutaneous-inguinal lymph node model also successfully simulated lymph node metastasis,with simple operation and high repeatability,a tumorigenesis rate of up to 100%,but its metastasis time was slightly longer than the hind paw-popliteal lymph node model.The inguinal lymph node-contralateral lymph node model was also a successful lymph node metastasis model,but with difficult operation,only 50%tumor-bearing rate,and poor repeatability.Lymph node metastasis model was not successfully established in the other 3 tumor-bearing models(under the tongue-internal jugular scapular tongue muscle lymph node model,bone marrow-inguinal lymph node model and right upper back skin-axillary lymph node model)in a short time,with no tumor cells observed in the pathological sections.Conclusion Through the comprehensive comparison of multiple models,mouse hind paw-popliteal lymph node model is the most suitable for conducting related research.