To dissect the disease heterogeneity and identify the underlying cellular and molecular events related to metastasis of immature ovarian teratoma in children, single-cell RNA sequencing was performed for a 2-year-old patient with liver metastases from immature ovarian teratoma. A total of 5976 cells were obtained for further analysis, with a median unique molecular identifier count of 6011 per cell and a median number of 1741 genes detected per cell. Fourteen clusters were recognized, with the main lineages comprising epithelial cells, macrophages, fibroblasts, glial cells, and dendritic cells. Ten subclusters of epithelial cells were further defined, originating from the urinary tract, esophagus, bronchus, lung, skin, and gastrointestinal tract. An undefined UBE2C + population in an active state of proliferation was also identified and its biological processes were related to meiosis and maturation of oocytes. Pseudotime analysis revealed different distributions of epithelial cells in the development trajectory. In conclusion, a cluster of UBE2C + epithelial cells in an active state of proliferation was identified in an immature ovarian teratoma in a child, and may contribute to metastasis by regulating epithelial–mesenchymal transition. These findings help toward understanding the origin of the malignant behaviors, offer a potential biomarker for early determination of the tumor nature, and provide new ideas for the therapy of immature ovarian teratoma in children.

解剖病的异质性和确定儿童与未成熟畸胎瘤转移的基本细胞和分子事件，ş一个2岁的患者，从不成熟的卵巢畸胎瘤肝转移进行英格尔细胞RNA测序。总共获得5976个细胞用于进一步分析，每个细胞的中位独特分子标识符计数为6011，每个细胞中检测到的平均数为1741个基因。识别出十四个簇，其主要谱系包括上皮细胞，巨噬细胞，成纤维细胞，神经胶质细胞和树突状细胞。进一步定义了十个上皮细胞亚群，它们起源于尿道，食道，支气管，肺，皮肤和胃肠道。未定义的UBE2C +还确定了处于活跃增殖状态的种群，其生物学过程与卵母细胞的减数分裂和成熟有关。伪时间分析揭示了在发展轨迹中上皮细胞的不同分布。总之，在儿童的未成熟卵巢畸胎瘤中发现了一群处于活跃增殖状态的UBE2C +上皮细胞，它们可能通过调节上皮-间质转化来促进转移。这些发现有助于理解恶性行为的起源，为早期确定肿瘤性质提供潜​​在的生物标记，并为治疗儿童未成熟卵巢畸胎瘤提供新的思路。