乙醛脱氢酶阳性乳腺癌干细胞的分离培养及其生物学特性分析

 目的　证实人类乳腺癌MCF-7细胞系中存在ALDH+乳腺癌干细胞，并研究ALDH+乳腺癌干细胞体外增殖、侵袭能力等生物学特性。方法　应用流式细胞术从MCF-7细胞中分离并培养ALDH+ 乳腺癌干／祖细胞，通过划痕试验、MTT法生长曲线测定、以及Transwell法等检测ALDH+乳腺癌干细胞的生物学特性。结果　MCF-7细胞系中，CD-／low24 CD+44 细胞比例约为1.4 %，ALDH+ CD-／low24 CD+44 细胞比例约为1.2 %； ALDH+乳腺癌干细胞与CD-／low24 CD+44 细胞两者的生长曲线基本一致；CD-／low24 CD+44 ，ALDH+ CD-／low24 CD+44 组细胞划痕区细胞间距离明显缩短，其迁移能力明显强于对照组，且两群干细胞之间存在差异；Transwell实验结果，与对照组相比，CD-／low24 CD+44 、ALDH+ CD-／low24 CD+44 两组细胞有大量细胞过膜，三组MTT检测吸光度值分别为1.05±0.098、1.56±0.075、1.67±0.032。结论　MCF-7细胞系中存在CD-／low24 CD+44 和ALDH+ CD-／low24 CD+44 乳腺癌干细胞，ALDH可以作为鉴定乳腺癌干细胞的分子标志之一。

Isolation and in vitro propagation of aldehyde dehydrogenases positive breast cancer stem cells and investigation on biological property of these cells

Objective　To identify a ALDH+ cancer stem cell subpopulation in MCF-7 cells and to investigate the proliferation and differentiation characteristics of these cells in vitro. Methods　ALDH+ breast cancer stem cells were isolated from MCF-7 cells by flow cytometry and the biological property of ALDH+ breast cancer stem cells was examined by scarification test, MTT, growth curvature and transwell migration assay. Results　The ratio of CD-/low24 CD+44 cells was about 1.4 % in MCF-7 cells. The ratio of ALDH+ CD-/low24 CD+44 cells was about 1.2 %. The growth curvature of ALDH+ breast cancer stem cells was almost the same with that of CD-/low24 CD+44 cells. The distance between cells was obviously shorter in both CD-/low24 CD+44 cells scarification zone and ALDH+ CD-/low24 CD+44 cells scarification zone. The migration ability of CD-/low24 CD+44 cells and ALDH+ CD-/low24 CD+44 cells was stronger than control group cells. There were migration ability differences between CD-/low24 CD+44 cells and ALDH+ CD-/low24 CD+44 cells. The results of transwell experiments were in coincidence with above results. Lots of CD-/low24 CD+44 cells and ALDH+ CD-/low24 CD+44 cells were through the membrane. In MTT assay, absorbance values were 1.05±0.098, 1.56±0.075 and 1.67±0.032. Conclusion　CD-/low24 CD+44 and ALDH+ CD-/low24 CD+44 breast cancer stem cell subpopulation exist in MCF-7 cells. ALDH could potentially be used as a molecular marker to identify breast cancer stem cell subpopulation.