Varticovski Lyuba, Hollingshead Melinda G, Robles Ana I, Wu Xiaolin, Cherry James, Munroe David J, Lukes Luanne, Anver Miriam R, Carter John P, Borgel Suzanne D, Stotler Howard, Bonomi Carrie A, Nunez Nomelí P, Hursting Stephen D, Qiao Wenhui, Deng Chuxia X, Green Jeff E, Hunter Kent W, Merlino Glenn, Steeg Patricia S, Wakefield Lalage M, Barrett J Carl
Center for Cancer Research, National Cancer Institute, Frederick, Maryland.
Clin Cancer Res. 2007 Apr 1;13(7):2168-77. doi: 10.1158/1078-0432.CCR-06-0918.
The use of genetically engineered mouse (GEM) models for preclinical testing of anticancer therapies is hampered by variable tumor latency, incomplete penetrance, and complicated breeding schemes. Here, we describe and validate a transplantation strategy that circumvents some of these difficulties.
Tumor fragments from tumor-bearing MMTV-PyMT or cell suspensions from MMTV-PyMT, -Her2/neu, -wnt1, -wnt1/p53(+/-), BRCA1/p53(+/-), and C3(1)T-Ag mice were transplanted into the mammary fat pad or s.c. into naïve syngeneic or immunosuppressed mice. Tumor development was monitored and tissues were processed for histopathology and gene expression profiling. Metastasis was scored 60 days after the removal of transplanted tumors.
PyMT tumor fragments and cell suspensions from anterior glands grew faster than posterior tumors in serial passages regardless of the site of implantation. Microarray analysis revealed genetic differences between these tumors. The transplantation was reproducible using anterior tumors from multiple GEM, and tumor growth rate correlated with the number of transplanted cells. Similar morphologic appearances were observed in original and transplanted tumors. Metastasis developed in >90% of mice transplanted with PyMT, 40% with BRCA1/p53(+/-) and wnt1/p53(+/-), and 15% with Her2/neu tumors. Expansion of PyMT and wnt1 tumors by serial transplantation for two passages did not lead to significant changes in gene expression. PyMT-transplanted tumors and anterior tumors of transgenic mice showed similar sensitivities to cyclophosphamide and paclitaxel.
Transplantation of GEM tumors can provide a large cohort of mice bearing mammary tumors at the same stage of tumor development and with defined frequency of metastasis in a well-characterized molecular and genetic background.
基因工程小鼠（GEM）模型用于抗癌疗法的临床前测试受到肿瘤潜伏期可变、不完全显性以及复杂繁殖方案的阻碍。在此，我们描述并验证了一种规避其中一些困难的移植策略。
将来自携带肿瘤的MMTV-PyMT小鼠的肿瘤片段或来自MMTV-PyMT、-Her2/neu、-wnt1、-wnt1/p53(+/-)、BRCA1/p53(+/-)和C3(1)T-Ag小鼠的细胞悬液移植到同基因或免疫抑制的未患癌小鼠的乳腺脂肪垫或皮下。监测肿瘤发展情况，并对组织进行处理以进行组织病理学和基因表达谱分析。在移除移植肿瘤60天后对转移情况进行评分。
无论植入部位如何，来自前叶腺体的PyMT肿瘤片段和细胞悬液在连续传代中比后叶肿瘤生长得更快。微阵列分析揭示了这些肿瘤之间的基因差异。使用来自多种GEM的前叶肿瘤进行移植具有可重复性，并且肿瘤生长速率与移植细胞数量相关。在原发肿瘤和移植肿瘤中观察到相似的形态学表现。超过90%移植PyMT肿瘤的小鼠发生转移，移植BRCA1/p53(+/-)和wnt1/p53(+/-)肿瘤小鼠的转移率为40%，移植Her2/neu肿瘤小鼠的转移率为15%。通过连续传代移植PyMT和wnt1肿瘤两代并未导致基因表达发生显著变化。移植PyMT肿瘤的小鼠和转基因小鼠的前叶肿瘤对环磷酰胺和紫杉醇表现出相似的敏感性。
GEM肿瘤移植可以提供大量处于肿瘤发展相同阶段且具有明确转移频率的患乳腺肿瘤小鼠，其处于特征明确的分子和遗传背景中。
