钙离子,CACNA1A,ABCB1基因间交互作用对BECTS型癫痫疗效影响的研究

Benign childhood epilepsy with centrotemporal spikes (BECTS) is one of the age-dependent epilepsy syndromes. In prep genome-wide association studies (GWAS), we compared 1800 cases with BECTS and 3115 heathy control, and discovered TMEM63C loci at a genome-wide level of significance. TMEM63C is related to calcium activated cation channel activity. We analyzed clinical information, and found that 62.9% of the patients received monotherapies, and 10.6% received multidrug therapy in this epilepsy with “good prognosis”, we also found that season is one of the factors that affect drug efficacy in patients. Thus, the purpose of this study is to analyze how gene-gene interaction and gene-environment interaction affect response to AEDs in patients with BECTS. We propose two hypotheses that ① CACNA1A may interact with ABCB1 polymorphisms to affect the drug response in patients with BECTS; ② Calcium ion may interact with CACNA1A and ABCB1 gene to affect the drug response in patients with BECTS. This study is based on the largest cohort of Han ethnic children with BECTS, and plans to follow this cohort for 3 years. We aim to analyze the effect of interaction between calcium ion, CACNA1A and ABCB1 on the response to AEDs in patients with BECTS, to construct plasmid with different CACNA1A and ABCB1 genotype and observe the AEDs’ impact on cell membrane potential under different calcium level via patch clamp, to elucidate the mechanism by which patients respond to AEDs so differently, therefore to provide new evidence for precision medicine.

儿童良性癫痫伴中央颞区棘波（BECTS）是一种年龄依赖的癫痫综合征，前期的GWAS研究中，我们通过1800例BECTS患儿及3115例正常对照发现钙通道活性基因TMEM63C与BECTS发病相关，通过分析1817例BECTS患儿的临床资料，发现这种“预后良好的”癫痫中62.9%的患儿接受单一抗癫痫药物（AEDs）治疗，10.6%患儿接受多药治疗，同时还发现季节因素影响治疗效果。因此，基因-基因，基因-环境因素如何影响BECTS患儿的药物疗效是本研究的目的所在。本课题提出两个科学问题①CACNA1A与ABCB1基因多态性可能会产生交互作用从而影响AEDs疗效；②钙离子可能与CACNA1A及ABCB1基因交互作用影响AEDs疗效。为此，本研究就钙离子、CACNA1A、ABCB1交互作用对BECTS患儿药物疗效的影响进行研究，同时构建质粒在细胞水平阐明其机制，为精准治疗提供新的依据。

儿童良性癫痫伴中央颞区棘波（Benign epilepsy with centrotemporal spikes，BECTS）是儿童期最常见的特发性部分性癫痫，在15岁以下儿童的发病率为6.2-21/10万，占到儿童每年新发癫痫病人总数的23% ,然而该病的治疗现状如何，影响药物治疗效果的因素有哪些目前尚不明了。因此课题组建立了国际上最大样本的BECTS队列库（共入组2234例BECT患儿）和国际上最大的BECTS样本库（2216例DNA样本），总结了中国儿童BECTS临床特征，治疗现状和预后。完成CACNA1A和ABCB1基因多态性检测，分析其与BECTS患儿抗癫痫药物疗效的相关性分析，以及基因之间有无交互作用，发现ABCB1（rs1128503，rs1045642）和基因CACNA1A（rs7254351, rs2074880, rs16030, rs2248069, rs10416717）多态性位点与BECT不同治疗反应组间（难控制，易控制）无统计学差异。基因间交互作用与药物治疗效果也无相关性。完成了335份药物治疗的BECT患儿骨代谢指标（其中难控制26份，易控制309份），采用逻辑回归的方法分析了骨代谢指标和药物治疗效果的关系，结果发现抗癫痫药物治疗会影响患儿骨代谢，尤其是丙戊酸钠和碱性磷酸酶、CTx、Mg、OCN和VD均显著相关，骨代谢指标中只有血磷与药物疗效有相关性。在基因多态性与骨代谢交互作用与BECT患儿药物疗效相关性方面，发现CACNA1A rs10416717和CTx存在交互作用，共同对疗效存在影响，rs16030与碱性磷酸酶之间存在交互作用，共同对疗效存在影响。在此基础上构建含有CACNA1A rs16030基因型的质粒转染转染Nav1.5细胞系，采用全细胞膜片钳技术来研究记录动力学I-V曲线，从细胞水平证实了基因与骨代谢的交互作用。因此治疗过程中监测患儿的骨代谢水平，不仅可以预防抗癫痫药物对于发育期儿童骨代谢的影响，还有可能影响BECTS患儿的疗效。