神经母细胞瘤细胞系裸鼠转移模型及局部皮下荷瘤模型的建立

Establishment of subcutaneously transplanted and metastatic neuroblastoma models in nude mice

目的建立人神经母细胞瘤（NB）裸鼠荷瘤模型，研究NB的侵袭、转移机制以及实验治疗的可能性。方法体外培养人NB细胞系，取对数生长期瘤细胞，以1×10^7个／0．1ml细胞悬液接种于裸小鼠右侧前肢肋腹部皮下，观察荷瘤的生物学特性，并进行病理组织学检查及基因芯片分析，检测皮下荷瘤组织、转移瘤组织和患儿原发肿瘤组织的神经元特异性烯醇化酶（NSE）表达。结果48只裸鼠中，荷瘤成功36只，总荷瘤率为75．0％。其中5只裸鼠肿瘤体积很大，甚至达到裸鼠自身体重的1／2，但未发生转移；4只裸鼠接种部位无肿瘤生长，却发生全身转移；6只裸鼠既有局部肿瘤生长，又发生转移。本组有10只裸鼠发生转移，转移率为20．8％（10／48）。结论成功建立人NB裸鼠荷瘤模型并稳定传代，肿瘤的移植生长率和转移率均较高，是NB体内研究理想的动物模型。NB具有异质性，可能是NB转移的重要原因。

Objective To establish a treMor-bearing nude mouse model of human neuroblastoma in order to study the mechanisms of neuroblastoma invasion and metastasis, and to investigate potential therapeutic modalities in the experimental animal models. Methods A human neuroblastoma cell line was cultured in vitro. 1 ×10^7 cells undergoing exponential growth were collected in 0. 1 ml of suspension and subcutaneously inoculated into the right flank next to the forelimb in nude mice. The biological characteristics of the developed tumors were observed, and histopathological and DNA microarray analyses were performed. The expressions of NSE in the subcutaneous tumor, metastatic tumor and the primary neuroblastoma tumor tissues from a pediatric patient were analyzed by immunohistoehemistry. Results Tumors successfully grew in 36 out of 48 injected mice, with a total tumor-formation rate of 75.0%. Metastasis occurred in 10 cases, and the metastatic rate was 20.8%. Tumors in five injected mice grew locally without metastasis. These tumors had large volume and the tumor weight reached up to half of the body weight of the host animal. Four mice exhibited systemic metastasis without tumor growth at the primary inoculation site. There were six mice with locally growing tumor accompanied by metastasis. Conclusion We have successfully established a human neuroblastoma xenograft model in nude mice with high tumor growth and metastatic rates. This model depicting the natural cell growth, local infiltration and distant metastasis characteristics of human neuroblastoma, providing an ideal animal model for in vivo studies of neuroblastoma. In addition, the resuhs of this study indicate the heterogeneous nature of neuroblastoma, it may play an important role in metastasis of this tumor.