Biological features of CD90+ tumor stem cells in ovarian cancer

Liu Zhi-hui; Xiang Zhi-hui

doi:10.3969/j.issn.2095-4344.2016.10.014

Abstract：BACKGROUND:Thinking from ovarian cancer stem cel theory shows that: in the tumor cels, there are a fraction of stem cels with self-renewing ability and multipotent differentiation, which are the root causes of ovarian cancer recurrence and drug resistance. Studies have shown that CD90 can be used as a surface marker of mesenchymal stem cels and stem cels of other cancers. <br> OBJECTIVE:To explore the biological features of CD90+ tumor cels from ovarian cancer tissues. <br> METHODS: Primary ovarian cancer cels were isolated from the abdominal dropsy of ovarian cancer patients to sort CD90+ and CD90- cels using flow cytometry. RT-PCR was used to detect expressions of stem cel-related genes and epithelial to mesenchymal transition-related genes. Cel invasion was observed by Transwel invasion assay, cel proliferation and differentiation observed by clone formation assay, stem cel potential observed by suspension sphere-forming assay, and tumor formation rate observed byin vivo tumorigenicity experiment. <br> RESULTS AND CONCLUSION:Compared with the CD90- cels, the expressions of CD44, CD133, ALDH1, N-cad and Vimentine were significantly higher in the CD90+cels (P < 0.05), but the expression of E-cad was significantly decreased in the CD90+ cels (P < 0.05). Tumor formation rates of CD90- and CD90+ cels were increased significantly with the increase of seeded cel number, which was more obvious in CD90+ cels. The number of transmembrane cels, the number of cel clones and the number of suspended spheres were significantly higher in the CD90+ cels than the CD90- cels (P < 0.05). Experimental findings from this study show that CD90+ cels highly express epithelial to mesenchymal transition-related genes and stem cel-related genes, with higher invasion, proliferation and differentiation, in vivo tumorigenicity and potential of stem cels. CD90+ cel separation may be a new method to separate ovarian cancer stem cels.