Enrichment of cancer stem cells by cotton fiber

Abstract

Isolation and expansion of cancer stem cells (CSCs) plays a main role in the better understanding of cancer biology as cancer is maintained by these few cancer cells with stem cell properties. Conventional methods to improve the isolation of CSCs at present are unreliable or lower producing. The hampered development of an effective method to enrich CSCs may create some substantial gaps in the advancement of an effectual therapeutic strategy in the field of cancer biology. In this study, we first obtained PC12 cell spheres using a conventional method and carefully characterized them as CSCs. Then we further developed a new, simple method for selecting and expanding CSCs. In our system, PC12 cells were cultured on a supporting material of cotton fibers treated by NH₃ plasma. This allowed the CSCs to grow readily into individual round colonies. Our findings from various experiments such as expression of surface receptor markers, drug resistance ability, gene and protein expression, spheroid colony formation and in vivo tumorigenicity support that the cotton fiber dramatically promotes the proliferation and enrichment of cells possessing the hallmarks of CSCs. Thus, our study strongly indicates that cotton fiber scaffolds will facilitate the study of CSC biology and provide a new suitable in vitro model for the discovery of more efficacious anti-cancer therapies.