Human pluripotent stem cells (hPSCs) have generated significant interest in the scientific community based on their potential applications in regenerative medicine. However, numerous research groups have reported a propensity for genomic alterations during hPSC culture that poses concerns for basic research and clinical applications. Work from our laboratory and others has demonstrated that amplification of chromosomal regions is correlated with increased gene expression. To date, the phenotypic association of common genomic alterations remains unclear and is a cause for concern during clinical use. In this study, we focus on trisomy 17 and a list of candidate genes with increased gene expression to hypothesize that overexpressing 17q25 located ARHGDIA will confer selective advantage to hPSCs. HPSC lines overexpressing ARHGDIA exhibited culture dominance in co-cultures of overexpression lines with nonoverexpression lines. Furthermore, during low-density seeding, we demonstrate increased clonality of our ARHGDIA lines against matched controls. A striking observation is that we could reduce this selective advantage by varying the hPSC culture conditions with the addition of ROCK inhibitor (ROCKi). This work is unique in (1) demonstrating a novel gene that confers selective advantage to hPSCs when overexpressed and may help explain a common trisomy dominance, (2) providing a selection model for studying culture conditions that reduce the appearance of genomically altered hPSCs, and (3) aiding in elucidation of a mechanism that may act as a molecular switch during culture adaptation.

中文翻译：

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ARHGDIA 赋予分离的人类多能干细胞选择性优势

人类多能干细胞 (hPSC) 基于其在再生医学中的潜在应用，引起了科学界的极大兴趣。然而，许多研究小组报告了在 hPSC 培养过程中基因组改变的倾向，这对基础研究和临床应用提出了担忧。我们实验室和其他实验室的工作表明，染色体区域的扩增与基因表达的增加有关。迄今为止，常见基因组改变的表型关联仍不清楚，并且在临床使用期间引起关注。在这项研究中，我们关注 17 三体和一系列基因表达增加的候选基因，以假设过度表达的 17q25 位于ARHGDIA将赋予 hPSCs 选择性优势。过表达ARHGDIA 的HPSC 系在过表达系与非过表达系的共培养中表现出文化优势。此外，在低密度播种期间，我们展示了我们的 ARHGDIA 系对匹配对照的克隆性增加。一个惊人的观察结果是，我们可以通过添加 ROCK 抑制剂 (ROCKi) 来改变 hPSC 培养条件来降低这种选择性优势。这项工作的独特之处在于 (1) 展示了一种新基因，该基因在过度表达时赋予 hPSCs 选择优势，并可能有助于解释常见的三体优势，(2) 为研究减少基因组改变的 hPSCs 出现的培养条件提供选择模型，以及(3) 帮助阐明在培养适应过程中可能充当分子开关的机制。