基于脑类器官的细胞治疗肿瘤发生评估平台。

BACKGROUND: Tumorigenicity represents a critical challenge in stem cell-based therapies requiring rigorous monitoring. Conventional approaches for tumorigenicity evaluation are based on animal models and have numerous limitations. Brain organoids, which recapitulate the structural and functional complexity of the human brain, have been widely used in neuroscience research. However, the capacity of brain organoids for tumorigenicity evaluation needs to be further elucidated. METHODS: A cerebral organoid model produced from human pluripotent stem cells (hPSCs) was employed. Meanwhile, to enhance the detection sensitivity for potential tumorigenic cells, we created a glioblastoma-like organoid (GBM organoid) model from TP53/PTEN hPSCs to provide a tumor microenvironment for injected cells. Midbrain dopamine (mDA) cells from human embryonic stem cells were utilized as a cell therapy product. mDA cells, hPSCs, mDA cells spiked with hPSCs, and immature mDA cells were then injected into the brain organoids and NOD SCID mice. The injected cells within the brain organoids were characterized, and compared with those injected in vivo to evaluate the capability of the brain organoids for tumorigenicity evaluation. Single-cell RNA sequencing was performed to identify the differential gene expression between the cerebral organoids and the GBM organoids. RESULTS: Both cerebral organoids and GBM organoids supported maturation of the injected mDA cells. The hPSCs and immature mDA cells injected in the GBM organoids showed a significantly higher proliferative capacity than those injected in the cerebral organoids and in NOD SCID mice. Furthermore, the spiked hPSCs were detectable in both the cerebral organoids and the GBM organoids. Notably, the GBM organoids demonstrated a superior capacity to enhance proliferation and pluripotency of spiked hPSCs compared to the cerebral organoids and the mouse model. Kyoto Encyclopedia of Genes and Genomes analysis revealed upregulation of tumor-related metabolic pathways and cytokines in the GBM organoids, suggesting that these factors underlie the high detection sensitivity for tumorigenicity evaluation. CONCLUSIONS: Our findings suggest that brain organoids could represent a novel and effective platform for evaluating the tumorigenic risk in stem cell-based therapies. Notably, the GBM organoids offer a superior platform that could complement or potentially replace traditional animal-based models for tumorigenicity evaluation.

背景：肿瘤发生是基于干细胞的治疗方法所面临的一个关键挑战，需要进行严格的监测。传统的肿瘤发生评估方法基于动物模型，存在许多局限性。脑类器官能够重现人脑的结构和功能复杂性，已被广泛应用于神经科学研究。然而，脑类器官在肿瘤发生评估方面的能力仍需要进一步阐明。

方法：本研究采用了源自人类多能干细胞（hPSC）的脑类器官模型。同时，为了提高对潜在致瘤细胞的检测灵敏度，我们从 TP53/PTEN hPSC 中创建了一个类似于胶质母细胞瘤的类器官（GBM 类器官）模型，为注入的细胞提供肿瘤微环境。从中胚胎干细胞中获得的中脑多巴胺（mDA）细胞被用作细胞治疗产品。将 mDA 细胞、hPSC、混入 hPSC 的 mDA 细胞和未成熟的 mDA 细胞分别注入脑类器官和 NOD SCID 小鼠中。对脑类器官中的注入细胞进行了特征分析，并与体内注射的细胞进行比较，以评估脑类器官的肿瘤发生评估能力。进行单细胞 RNA 测序以鉴定脑类器官和 GBM 类器官之间的差异基因表达。

结果：脑类器官和 GBM 类器官均支持注入的 mDA 细胞的成熟。与注入脑类器官和 NOD SCID 小鼠的细胞相比，注入 GBM 类器官的 hPSC 和未成熟的 mDA 细胞具有更高的增殖能力。此外，在脑类器官和 GBM 类器官中均能检测到混入的 hPSC。值得注意的是，与脑类器官和小鼠模型相比，GBM 类器官能够显著增强混入的 hPSC 的增殖和多能性。京都基因与基因组百科全书分析显示，GBM 类器官中肿瘤相关代谢途径和细胞因子的表达上调，提示这些因素是提高肿瘤发生评估检测灵敏度的基础。

结论：我们的研究结果表明，脑类器官可能代表一种用于评估基于干细胞的治疗方法中肿瘤发生风险的新型有效平台。值得注意的是，GBM 类器官提供了一个更优越的平台，可以补充或可能替代传统的基于动物模型的肿瘤发生评估方法。