Huo Ran, Wang Jie, Sun Ying-Fan, Weng Jian-Cong, Li Hao, Jiao Yu-Ming, Xu Hong-Yuan, Zhang Jun-Ze, Zhao Shao-Zhi, He Qi-Heng, Wang Shuo, Zhao Ji-Zong, Cao Yong
Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
China National Clinical Research Center for Neurological Diseases, Beijing, China.
Front Neurol. 2022 Aug 26;13:946324. doi: 10.3389/fneur.2022.946324. eCollection 2022.
To investigate the clinical characteristics of cerebral cavernous malformations (CCMs) with somatic mutation.
We performed a retrospective review of our CCMs database between May 2017 and December 2019. The patients with simplex CCMs identified to harbor a or CCM gene somatic mutation were included. Clinical characteristics were recorded. Univariate and multivariate logistic analyses were used to assess the risk factors associated with hemorrhage events of CCMs. To explore the underlying mechanism, we transfected MEKK3-I441M-overexpressing and -knockdown lentiviruses into human umbilical vein endothelial cells (HUVECs) and investigated thrombomodulin (TM) and tight junctions (TJs) protein expression by western blotting and immunofluorescence. Finally, immunohistochemistry was used to validate TM and TJs protein expression in surgical samples.
Fifty simplex CCMs patients were included, comprising 38 mutations and 12 CCM gene mutations. Nine (23.7%) patients with mutations and 11(91.7%) patients with CCM gene mutations exhibited overt hemorrhage, respectively. Multivariate logistic analyses revealed that mutation was associated with a lower risk of hemorrhage events. In the experiments, ZO-1 expression was not reduced in MEKK3-I441M-overexpressing HUVECs compared with wild type, whereas it was significantly decreased in -knockdown HUVECs compared with control. In the MEKK3-I441M-overexpressing HUVECs, TM expression was increased, and the NF-κB pathway was significantly activated. After treatment with an NF-κB signaling inhibitor, TM expression was further upregulated. Meanwhile, TM expression was increased, but the NF-κB pathway was not activated in knockdown HUVECs. Accordingly, immunohistochemistry showed that ZO-1 expression in the mutant samples was significantly higher than that in the CCM-mutant samples. TM expression in the -mutant lesions was significantly lower than that in the CCM-mutant samples.
Simplex CCMs with mutation occasionally present with overt hemorrhage, which is associated with the biological function of mutation.
研究伴有体细胞突变的脑海绵状血管畸形（CCM）的临床特征。
我们对2017年5月至2019年12月期间的CCM数据库进行了回顾性分析。纳入了经鉴定携带KRIT1或CCM基因体细胞突变的单纯性CCM患者。记录临床特征。采用单因素和多因素逻辑回归分析评估与CCM出血事件相关的危险因素。为探究潜在机制，我们将过表达和敲低MEKK3-I441M的慢病毒转染到人脐静脉内皮细胞（HUVECs）中，并通过蛋白质印迹法和免疫荧光法研究血栓调节蛋白（TM）和紧密连接（TJs）蛋白的表达。最后，采用免疫组织化学法验证手术样本中TM和TJs蛋白的表达。
纳入50例单纯性CCM患者，其中38例为KRIT1突变，12例为CCM基因突变。9例（23.7%）KRIT1突变患者和11例（91.7%）CCM基因突变患者分别出现明显出血。多因素逻辑回归分析显示，KRIT1突变与出血事件风险较低相关。在实验中，与野生型相比，过表达MEKK3-I441M的HUVECs中ZO-1表达未降低，而与对照相比，敲低MEKK3-I441M的HUVECs中ZO-1表达显著降低。在过表达MEKK3-I441M的HUVECs中，TM表达增加，且NF-κB通路显著激活。用NF-κB信号抑制剂处理后，TM表达进一步上调。同时，敲低MEKK3-I441M的HUVECs中TM表达增加，但NF-κB通路未激活。因此，免疫组织化学显示，突变样本中的ZO-1表达显著高于CCM突变样本。KRIT1突变病变中的TM表达显著低于CCM突变样本。
伴有KRIT1突变的单纯性CCM偶尔会出现明显出血，这与KRIT1突变的生物学功能有关。
