Evaluation of human iPSCs by neural differentaition and tumorigenicity

点击翻译按钮获取中文摘要

Human-induced pluripotent stem cells (hiPSCs) hold great promise for regenerative medicine. Despite the importance in evaluating their quality for future cell therapy, there are no precise analyses for assessing abnormal differentiation and tumorigenicity. We demonstrated that pre-evaluated hiPSC clones, established by retroviruses or integration-free episomal vectors, may exhibit glioma-like tumor formation by the transplantation of hiPSC-derived neural stem/progenitor cells into NOD/SCID mice. Notably, the tumorigenicities were closely associated with incomplete reprogramming of hiPSCs, revealed by the expressions of newly identified human embryonic stem cell signature genes or DNA repair genes. This incomplete reprogramming resulted in genomic instability not in an undifferentiated state, but during neural differentiation. Moreover, cluster of DNA repair genes may provide a useful "scorecard" for easy and quick evaluation of the incomplete reprogramming of hiPSCs.