人肺腺癌干细胞的分离及鉴定

Isolation and identification of human lung adenocarcinoma stem cells

目的:从人肺腺癌细胞株中分离及鉴定具有干细胞特征的高致瘤性癌干细胞。方法:采用磁性细胞分选(magnetic activated cell sorting,MACS)技术将肺腺癌细胞分成多个亚群,然后应用流式细胞及RT-PCR技术检测干细胞相关标志表达,通过NOD-SCID小鼠移植评估其致瘤性。结果:在A549和SPC-A肺腺癌细胞中发现一个新颖的癌细胞亚群,此类癌细胞的表型特征为CD24+IGF-1R+,具有高侵袭性和高致瘤性,在NOD-SCID小鼠中仅需移植100个细胞即可形成肿瘤,其致瘤能力是上述标志阴性细胞的1000倍。此外,这些细胞表达胚胎干细胞标志(OCT4和Bmi-1)及肺干细胞标志(CCSP,SP-C,TTF-1和Gremlin),类似小鼠肺脏细支气管肺泡干细胞(bronchioalveolar stem cells,BASC),并具有自主生长特性,能够在无血清条件下长期培养。结论:人体肺腺癌中CD24+IGF-1R+细胞属于BASC样癌干细胞。

Objective：To isolate and characterize the highly tumorigenic cancer stem cells with stem cell features from the established human lung adenocarcinoma cell lines. Methods： The cell subtypes were separated by magnetic activated cell sorting （MACS） technique. The stem cell-related markers on the isolated cells were detected by using flow cytometry and RT-PCR. The tumorigenic potent of the isolated cells was evaluated via the transplantation into NOD-SCID mice. Results： A novel cell subtype was identified in A 549 and SPC-A1 lung adenocarcinoma cell lines. These cells were characterized as a phenotype of CD 24^＋ IGF-1R^＋ , possessed the property of high invasiveness and high tumorigenesis. Tumor could be induced in NOD-SCID mice by transplantation of CD 24^＋ IGF- 1R^＋ cells at 100 cells per mouse. The tumorigenicity of CD 24^＋ IGF-1R^＋ cells had 1000-fold increase compared with CD 24^- IGF-1R^- cells. In addition, the CD 24^＋ IGF-1R^＋ cells expressed embryonic stem cell markers （ OCT 4 and Bmi-1 ） and lung stem cell markers （ CCSP, SP-C, TTF-1, and Gremlin） , suggesting that they had the features identical to the bronchioalveolar stem cells （BASC） in the lung of mice. These cells also exhibited autonomous growth features and could be cultured in serum-free conditions for a long time. Conclusion：The CD 24^＋ IGF-1R^＋ cells in human lung adeocarcinoma belongs to the BASC-like cancer stem cells.