Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120, People's Republic of China.
Int J Colorectal Dis. 2011 Oct;26(10):1279-85. doi: 10.1007/s00384-011-1248-y. Epub 2011 Jun 14.
Colorectal cancer stem cells (Cr-CSCs) are involved in the growth of colon cancer, but their specific role in tumor biology, including metastasis, is still unclear. Currently, methods for sorting Cr-CSCs are based on the expression of surface markers (e.g., CD133(+), CD44(+), and aldehyde dehydrogenase 1 (ALDH1(+))); however, the specificity of these markers for Cr-CSCs is uncertain.
This study aimed to develop more effective ways of isolating and purifying Cr-CSCs.
Suspension culture was used for isolation of Cr-CSCs. And spheroid cells were performed by side population technology, and the putative molecular marker analysis of colorectal cancer stem cell. Migration assay and chemoresistance experiment were conducted between the adherent cells and spheroid cells.
HT29 colon cancer cells grew well in suspension culture. The percentage of CD44(+) cancer cell of spheroid cells was 68 times higher than that of adherent cells (89.5% vs. 1.3%), but there was no obvious difference in the percentage of CD133(+) cells (6.25% vs. 5.6%). Moreover, it is worth noting that the percent of CD133 (+)/CD44(+) cells remarkably rose (from 0.6% to 5.4%). The expression of ALDH1 was markedly increased (7.5% vs. 20.5%) for the spheroid cells than the adherent cells. The side population within the spheroid population dramatically increased from 0.2% to 6.3%. The resistance of spheroid cells to 5-FU was higher than that of adherent cells, as was their ability to migrate in the presence of SDF-1α.
Suspension culture is an effective approach for enriching Cr-CSCs and can provide an inexhaustible supply of genetically stable colon cancer stem cells for targeted Cr-CSC studies. Spheroid cell models also enable the study of colon cancer chemoresistance and metastasis and may help to elucidate the role of cancer stem cells in colon cancer.
结直肠肿瘤干细胞（Cr-CSCs）参与结肠癌的生长，但它们在肿瘤生物学中的特定作用，包括转移，仍不清楚。目前，Cr-CSCs 的分选方法基于表面标志物的表达（例如，CD133(+)、CD44(+)和醛脱氢酶 1（ALDH1(+)））；然而，这些标志物对 Cr-CSCs 的特异性尚不确定。
本研究旨在开发更有效的分离和纯化 Cr-CSCs 的方法。
悬浮培养用于分离 Cr-CSCs。通过侧群技术进行球体细胞培养，并对结直肠肿瘤干细胞的假定分子标志物进行分析。在贴壁细胞和球体细胞之间进行迁移实验和化学耐药实验。
HT29 结肠癌细胞在悬浮培养中生长良好。球体细胞中 CD44(+)癌细胞的比例比贴壁细胞高 68 倍（89.5%比 1.3%），但 CD133(+)细胞的比例没有明显差异（6.25%比 5.6%）。此外，值得注意的是，CD133 (+)/CD44(+)细胞的比例明显上升（从 0.6%上升至 5.4%）。球体细胞中 ALDH1 的表达明显增加（7.5%比 20.5%）。球体细胞中侧群细胞的比例从 0.2%显著增加至 6.3%。与贴壁细胞相比，球体细胞对 5-FU 的耐药性更高，在 SDF-1α存在的情况下，球体细胞的迁移能力更强。
悬浮培养是富集 Cr-CSCs 的有效方法，可为靶向 Cr-CSC 研究提供源源不断的遗传稳定的结肠肿瘤干细胞。球体细胞模型还可以研究结肠癌的化学耐药性和转移，有助于阐明肿瘤干细胞在结肠癌中的作用。
