PO.TB05.02 · 肿瘤生物学
转录因子DMRTA2调控儿童高级别胶质瘤的放射状胶质细胞维持和致瘤性
The transcription factor DMRTA2 regulates radial glial maintenance and tumorigenicity of pediatric high-grade glioma
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
脑肿瘤是儿童癌症相关死亡的主要原因。其中，儿童型弥漫性高级别胶质瘤（HGG）占儿童脑肿瘤死亡的40%。弥漫性半球胶质瘤（DHG）、H3 G34突变型（DHG-H3G34），代表了一种预后不良的高度恶性HGG亚型。尽管发育程序失调已被认为与这些肿瘤有关，但驱动亚型特异性肿瘤发生的确切机制仍不清楚。DMRTA2是Doublesex-mab3相关（DMRT）转录因子家族的成员，已被认为与神经祖细胞的增殖和维持有关。然而，其在人脑发育和儿童胶质瘤中的功能尚未完全阐明。
为填补这一空白，我们首先分析了先前发表的来自人类胎儿脑和脑类器官的单细胞RNA测序数据集。我们发现DMRTA2在神经祖细胞群体中稳健表达，尤其是在放射状胶质（RG）细胞中。为研究DMRTA2在人脑发育中的功能作用，我们使用CRISPR-Cas9基因组编辑在人胚胎干细胞（hESC）系中敲除了DMRTA2基因，并将其分化为脑类器官。DMRTA2敲除类器官表现出体积减小、增殖下降以及RG细胞的显著耗竭，提示DMRTA2在早期皮层发育中发挥重要作用。
我们接下来检查了DHG-H3G34患者肿瘤中的DMRTA2表达，观察到与其他儿童脑肿瘤亚型相比其高度且特异性的表达。为研究DMRTA2在DHG-H3G34中的作用，我们在自行开发的基于hESC的DHG-H3G34模型细胞中敲除了DMRTA2。DMRTA2缺失导致RG样群体显著减少，分化细胞显著增加。在我们使用荧光素酶标记的DMRTA2野生型（WT）和敲除（KO）细胞进行的小鼠异种移植研究中，DMRTA2缺失显著减少了体内肿瘤生长。KO肿瘤还表现出增殖减少和RG样细胞减少。
总之，我们的研究结果表明，DMRTA2是人类皮层发育中放射状胶质细胞的关键调控因子，并促进儿童DHG-H3G34肿瘤的致瘤性。
查看英文原文 English abstract
Brain tumor is the leading cause of cancer-related death in children. Among them, pediatric-type diffuse high-grade glioma (HGG) accounts for 40% of brain tumor deaths in children. Diffuse hemispheric glioma (DHG), H3 G34-mutant (DHG-H3G34), represents a highly malignant subtype of HGG with a poor prognosis. Although dysregulated developmental programs have been implicated in these tumors, the exact mechanisms that drive subtype-specific tumorigenesis remain unclear. DMRTA2, a member of the Doublesex-mab3-related (DMRT) transcription factor family, has been linked to the proliferation and maintenance of neural progenitor cells. However, its functions in human brain development and pediatric glioma are not yet fully understood.
To address this gap, we first analyzed previously published single-cell RNA-seq datasets from human fetal brains and cerebral organoids. We found robust DMRTA2 expression in neural progenitor populations, particularly in radial glial (RG) cells. To investigate the functional role of DMRTA2 in human brain development, we knocked out the DMRTA2 gene using CRISPR-Cas9 genome editing in human embryonic stem cell (hESC) lines and differentiated them into cerebral organoids. DMRTA2 KO organoids exhibited reduced size, decreased proliferation, and a marked depletion of RG cells, suggesting an important role of DMRTA2 in early cortical development.
We next examined DMRTA2 expression in DHG-H3G34 patient tumors and observed its high and specific expression compared to other subtypes of pediatric brain tumors. To investigate the role of DMRTA2 in DHG-H3G34, we knocked out DMRTA2 in hESC-based DHG-H3G34 model cells that we developed. Loss of DMRTA2 resulted in a significant decrease in RG-like population and a marked increase in differentiated cells. In our mouse xenograft studies using luciferase-labeled DMRTA2 WT and KO cells, loss of DMRTA2 significantly reduced tumor growth in vivo. KO tumors also displayed reduced proliferation and fewer RG-like cells.
Together, our findings suggest that DMRTA2 is a key regulator of radial glial cells in human cortical development and promotes tumorigenicity in pediatric DHG-H3G34 tumors.
利益披露 Disclosure
H. N. Royston, None..
A. B. Hampton, None..
E. G. Oliver, None..
J. Jackson, None..
I. F. Tella, None..
M. D. Emerson, None..
D. Bhagat, None..
D. Konno, None..
K. Funato, None.