摘要
目的:探讨乳腺癌细胞系MCF-7和MDA-MB-231中是否存在乳腺癌起始细胞(CD44+/CD24-/low)亚群;并分析Hedgehog信号通路在CD44+/CD24-/low乳腺癌起始细胞亚群中的表达。方法:应用荧光激活细胞分选方法检测与分选MCF-7和MDA-MB-231中的CD44+/CD24-/low细胞亚群和非CD44+/CD24-/low细胞亚群,并在激光共聚焦显微镜下进行观察确认。应用逆转录聚合酶链反应(RT-PCR)方法检测CD44+/CD24-/low细胞亚群和非CD44+/CD24-/low细胞亚群中Hedgehog信号通路重要基因PTCH(human patched gene)、SHH(sonic Hedgehog)、GIi-1(glioma-associated oncogene homoglog-1)和SMOH(smoothened homolog)的表达情况。结果:乳腺癌细胞系MCF-7和MDA-MB-231中CD44+/CD24-/low亚群,比例分别为(1.70±1.43)%和(94.2±1.2)%。乳腺癌细胞系MCF-7和MDA-MB-231的CD44+/CD24-/low亚群中Hedgehog信号通路处于明显活化状态,其中Hedgehog信号通路中重要下游信号分子GIi-1在MCF-7和MDA-MB-231细胞系CD44+/CD24-/low细胞亚群中的表达要明显高于非CD44+/CD24-/low细胞亚群(P分别为0.007和0.005)。结论:乳腺癌细胞系MCF-7和MDA-MB-231中存在CD44+/CD24-/low干细胞标志细胞亚群,其中Hedgehog信号通路处于明显活化状态。
To isolate and identify breast cancer initiating cells （CD44^＋/CD24^-/low cells） in breast cancer cell lines MCF-7 and MDA-MB-231 ,and to evaluate the activity of the Hedgehog signaling pathway in different subpopulations. Methods： CD44^＋/CD24^-/low subpopulation and non-CD44^＋/CD24^-/low subpopulation from breast cancer cell lines of MCF-7 and MDA-MB-231 were separated by fluorescence-activated cell sorting （FACS）. Laser Scanning Confocal Microscope was used to identify CD44^＋/CD24^-/low cells. Reverse transcription-polymerase chain reaction （RT-PCR） was employed to analyze the expression of Human Patched gene （ PTCH）, Sonic Hedgehog （SHH） , glioma-associated oncogene homoglog-1 （GIi-1）, smoothened homolog （SMOH） and GAPDH of CD44^＋/CD24^-/low subpopulation and non-CD44^＋/CD24^-/low subpopulation from MCF-7 and MDA-MB-231. Results： The CD44^＋/ CD24-/low subpopulation in MCF-7 and MDA-MB-231 cell lines were （ 1.70±1.43 ） % and （94.2＋1.2） % respectively. The Hedgehog signaling pathways were active in CD44^＋/CD24^-/low subpopulation of MCF-7 and MDA-MB-231 cell lines. The expression of transcription factor GIi-1, which was downstream components of the hedgehog pathway, was assayed and the results showed that the level of GIi-1 mRNA of CD44^＋/CD24^-/low ceils was much higher than that of non-CD44^＋/CD24^-/low cells （P = 0. 007 in MCF-7, and 0.005 in MDA-MB-231 ）. Conclusion： Breast cancer initiating cells （CD44^＋/ CD24^-/low subpopulation） exist in MCF-7 and MDA-MB-231 cell lines. The Hedgehog signaling pathway is active in the subpopulation of MCF-7 and MDA-MB-231 cell lines.
出处
《北京大学学报（医学版）》
CAS
CSCD
北大核心
2008年第5期480-485,共6页
Journal of Peking University:Health Sciences
关键词
乳腺肿瘤
肿瘤干细胞
信号传导
Breast neoplasms
Tumor stem cells
Signal pathway
