人肺癌NCI-H446细胞生成肿瘤干细胞球

Tumor stem cell spheres generated from human lung cancer cells NCI-H446

目的探索人肺癌NCI-H446细胞系干细胞球体的培养,并鉴定其生物学特性。方法用无血清培养基培养人肺癌NCI-H446细胞得到肿瘤细胞球。将肿瘤细胞球传代扩增,并用含血清培养基培养促使其分化;四甲基偶氮唑盐(MTT)比色检测肿瘤球和普通NCI-H446细胞的增殖能力,并将肿瘤球和普通NCI-H446细胞分别植入裸鼠皮下,观察肿瘤形成;Transwell侵袭实验检测肿瘤球和普通NCI-H446细胞的侵袭能力的不同;流式细胞术检测CD133、CD44在肿瘤球和普通NCI-H446细胞中的表达,并筛选细胞表面标志物。结果在无血清培养基中,人肺癌NCI-H446细胞可以形成少量的肿瘤细胞球,并显示很强的自我更新和增殖能力,在含血清环境中能够诱导肿瘤球分化而贴壁生长;在动物实验中,接种5×105个细胞时,肿瘤球细胞较普通NCI-H446细胞显示更强的致瘤能力;在侵袭实验中,肿瘤球细胞的侵袭能力高于普通NCI-H446细胞;干细胞标志物CD133及CD44在肿瘤球细胞的表达较普通NCI-H446细胞明显增高。结论人肺癌细胞NCI-H446中存在癌干细胞,且可以通过无血清培养、分离和富集。

Objective To isolate and expand cancer stem cells in human lung cancer cell line NCI-H446 and to identify their biological properties. Methods NCI-H446 cells were cultured in serum-free conditions to generate tumor spheres. The tumor spheres were then expanded and cultured in a serum-containing medium to permit their differentiation. The proliferative capacity of the normal NC1-H446 cells and tumor sphere-forming cells were tested by MTT assay, and the tumorigenicity and invasion of the both normal and sphere-cells were evaluated using animal and Transwell invasion experiments. The expression of CD133 and CD44 on the surface of the normal NCI-H446 cells and tumor sphere-forming cells were detected by flow cytometry. Results A small number of floating tumor spheres were isolated and expanded in serum-free conditions and the cell of the spheres maintained a strong capacity for self-renewal and proliferation. These tumor spheres attached to the bottom of culture plates and began to differentiate in a serum-containing medium. The xenograft tumorigenicity of tumor sphere forming cells was significantly higher than that of the normal NCI-H446 cells while injecting 5 × 10^5 cells in animal experiments. The capability of invasion of tumor sphere forming cells was significantly higher than that of the normal NCI-H446 cells in transwell invasion experiments. The percentage of CD133, CD44 cell population was significantly higher in tumor spheres than that in the normal NC1-H446 cells. Conclusion Cancer stem cells exist in human lung cancer cell line NCI-H446 and can be isolated and expanded in serum-free conditions.