大鼠骨肉瘤肺转移模型的建立

Establishment of osteosarcoma pulmonary metastasis in rat model

目的:构建大鼠骨肉瘤的肺转移模型,为骨肉瘤肺转移的机理及治疗研究奠定基础。方法:RPMI1640培养基体外扩增UMR106细胞(大鼠骨肉瘤细胞株),分别用无血清培养基和鼠尾胶稀释成1×107cells/ml混悬液,原位注入3周龄SD大鼠胫骨近端骨髓腔内,每只0.2ml。观察成瘤情况,死后尸检肺转灶数目,X线检查骨质变化,组织学检查确定肿瘤性质。结果:两组大鼠原位成瘤率及肺转移率均达100%。X线检查示明显骨质破坏和瘤骨形成,组织学检查见肿瘤样骨基质形成,符合临床骨肉瘤各项特征。培养基组和鼠尾胶组肿瘤形成时间分别为(10.0±1.65)天和(17.8±0.87)天,差异有显著性(P<0.0001);肺转移灶数目分别为(155.25±36.63)个和(91.5±29.56)个,差异有显著性(P<0.0001);大鼠生存时间分别为(21.4±6.67)天和(40.6±9.52)天,差异也有显著性(P<0.0001)。结论:UMR106细胞原位移植SD大鼠建立骨肉瘤模型方法简单、重复性好、实验周期短、肺转移率100%,是研究骨肉瘤肺转移的理想动物模型。无血清培养基稀释法肿瘤形成及肺转移出现时间早,实验周期快,可用于骨肉瘤肺转移机制的研究。鼠尾胶稀释法肿瘤形成时间相对较晚,生存时间长,肺转移数目稍少,适用于骨肉瘤治疗方法的研究。

Objective：To establish the pulmonary metastasis model of osteosarcoma in rats. Methods：UMR106 cells （rat osteosarcoma strain） were cultured in RPMI1640 media and collected before transplantation and resuspended in serum-free media or collagen gel to a final concentration of 1 × 10^7 cells/ml. About 200μl cell suspensions were injected into the right proximal tibia of 3-week-old Sprague-Dawley rats. Twelve rats were used in every group sorted by resuspension fluid. All rats were treated by cyclosporin A and SMZ-TMP after transplantation. The dates of tumor appearance and rat death were noted, the size of tumor was measured once a week, the metastasis foci on the lung surface was counted and the limbs afflicted by tumor were observed by X-ray after death. Both the tumors in limb and lung were stained with hematoxylin and eosin,and analyzed by microscopy. Results：All rats developed local intratibial bone tumors that were radiographically and histologically similar to primary human osteosarcoma. The pulmonary metastasis foci were found in all rats at autopsy. The tumor formation time of serum-free media group was （10.0±1.65） days,shorter than that of collagen gel group, which was （17.8±0.87） days （P〈0.0001）. The metastasis foci in lung of serum-free media group were more than that of collagen gel group（ 155.25±36.63vs 91.5 ±29.56,P〈0.0001 ）. The rats of serum-free media group died earlier than collagen gel group （21.4days ±6.67days vs 40.6 days ±9.52days,P〈0.0001）. Conclusions：The osteosarcoma model established by UMR106 cell strain orthotopic transplantation in SD rats,which is reliable,easily manipulated,tumor formation quickly and pulmonary metastasis in 100 percent,is a perfect model for study pulmonary metastasis of osteosarcoma. The model established by cells resuspened in serum-free media is better for the mechanism study,while the model established by collagen gel is better for pulmonary metastasis treatment study.