尽管人类胚胎干细胞（hESCs）维护基因组完整性的机器非常有效，但体外培养期间遗传异常的频率对未来的临床应用是一个严重的问题。通过在广泛的时间点上（长达6年）进行hESCs传代，建立了具有不同传代数和不同细胞特性的等基因hESC系。我们发现，有丝分裂异常（如有丝分裂延迟、多极中心体和染色体错位）与多倍体相比早期传代（EP-hESCs）的正常拷贝数hESCs（EP-hESCs）并行增加。通过高分辨率的全基因组方法和转录组分析，我们发现，在20q11.21染色体上最小的DNA片段中，文化适应的hESCs高度表达了TPX2，这是一个关键的蛋白质，用于控制纺锤体装配和癌症恶性。与这些发现一致的是，在EP-hESCs中诱导表达TPX2可重现异常的有丝分裂事件，如有丝分裂进展的延迟、纺锤体的稳定、染色体错位和多倍体。这些研究表明，在文化适应的hESCs中，TPX2转录的增加可能会导致由于纺锤动力学改变而发生异常有丝分裂。©2023年作者（们），在Springer Science+Business Media，LLC的独家许可下，该公司为Springer Nature的一部分。

Despite highly effective machinery for the maintenance of genome integrity in human embryonic stem cells (hESCs), the frequency of genetic aberrations during in-vitro culture has been a serious issue for future clinical applications.By passaging hESCs over a broad range of timepoints (up to 6 years), the isogenic hESC lines with different passage numbers with distinct cellular characteristics, were established.We found that mitotic aberrations, such as the delay of mitosis, multipolar centrosomes, and chromosome mis-segregation, were increased in parallel with polyploidy compared to early-passaged hESCs (EP-hESCs) with normal copy number. Through high-resolution genome-wide approaches and transcriptome analysis, we found that culture adapted-hESCs with a minimal amplicon in chromosome 20q11.21 highly expressed TPX2, a key protein for governing spindle assembly and cancer malignancy. Consistent with these findings, the inducible expression of TPX2 in EP-hESCs reproduced aberrant mitotic events, such as the delay of mitotic progression, spindle stabilization, misaligned chromosomes, and polyploidy.These studies suggest that the increased transcription of TPX2 in culture adapted hESCs could contribute to an increase in aberrant mitosis due to altered spindle dynamics.© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.