Abstract LB-144: Derivation of a model of cancer stem cell from human induced pluripotent stem cells

Abstract

Abstract The existence of cancer stem cell (CSC) has been considered as one of the important reason as to why patients have a poor prognosis. However, heterotopic transplantation of embryonic stem cells and induced pluripotent stem cells has been shown to form teratoma, but not malignant teratoma. Since the microenvironment niche is playing a significant role for the proper differentiation of stem cells, the cancerous niche should drive stem cells into malignant cells in vivo. According to this hypothesis, we tried to generate cancer cells from human induced pluripotent stem (hiPS) cells. For the conversion into CSC, the conditioned medium from different human cancer cell lines was collected from confluent dishes and filtered using 0.22 micrometer filter. Then, hiPS cells, without MEF feeder cells, were maintained in the conditioned medium (CM) in the ratio of 1:1. The medium was changed every day with CM for 4 weeks. hiPS cells with the complete medium were used as control. For transplantation studies, 10^4 cells were suspended in HBSS and were xenotransplantated into NOD-SCID mice. After 3 months, tumors were excised and fixed in 10% neutral formalin buffer solution, or subjected to primary culture. The converted cells and primary cultured cells formed spheroids in suspension culture, and had tumorigenicity in vivo. The stemness of living cells was checked under fluorescent microscopy observation with rBC2LCN-FITC staining. The RNAs were extracted from converted cells and microarray analysis was perfomed. The RNA expression patterns of cell lines were visualized by sphered self-organizing map (sSOM) analysis. The sSOM analysis perfomed based upon various parameters shows the converted CSCs can be characterized into various cell types. Utilizing this method, we successfully established two different hiPS-CSC lines using CM from A172 and RERF-LC-KJ. The comprehensive understanding of cancer could be realized as the heterogeneity of cancer tissues is clarified and their component cells are identified. This study will lead to the development of the true personalized therapy of cancer in the future. Citation Format: Tomonari Kasai, Kenta Hoshikawa, Shuto Takejiri, Masashi Ikeda, Kazuki Kumon, Anna Sanchez Calle, Arun Vaidyanath, Akifumi Mizutani, Chen Ling, Masaharu Seno. Derivation of a model of cancer stem cell from human induced pluripotent stem cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr LB-144. doi:10.1158/1538-7445.AM2015-LB-144