摘要
目的:对18例原发中枢神经系统淋巴瘤(PCNSL)患者肿瘤组织进行全外显子测序,探索PCNSL的基因突变特点.方法:收集2018年9月至2020年12月在兰州大学第二医院病理科确诊的18例免疫功能正常(无HIV及服用免疫抑制剂病史)、病理类型为弥漫大B细胞淋巴瘤的PCNSL患者肿瘤组织,进行基于高通量测序的全外显子测序,平均测序深度＞100×.测序结果经数据处理及生物信息学分析,得到患者的基因突变全景及突变特征.结果:18例患者均检测到明显的体细胞突变,中位体细胞突变数目为321,以错义突变为主(约占90％),突变类型以C＞T为主(占50.2％),反映了与年龄相关的突变模式;前15位高频突变基因中,PSD3、DUSP5、MAGEB16、TELO2、FMO2、TRMT13、AOC1、PIGZ、SVEP1、IP6K3、TIAM1 为驱动基因.驱动基因通路富集结果显示,RTK-RAS、Wnt、NOTCH、Hippo、Cell-Cycle通路明显富集.各样本的肿瘤突变负荷在3.558 48/Mb-8.780 89/Mb之间,平均突变负荷4.953 32/Mb,与TCGA数据库中其他肿瘤的研究队列相比明显增高.结论:PCNSL频繁发生体细胞的错义突变,以点突变为主,突变类型主要为C＞T.驱动基因主要参与RTK-RAS、Wnt、NOTCH、Hippo通路信号传导,表明以上通路可能与PCNSL发病机制相关.PCNSL有显著的高肿瘤突变负荷,这或许是PD-1抑制剂治疗PCNSL有效的原因之一.
Abstract
Objective:To investigate gene mutation characteristics of primary central nervous system lymphoma(PCNSL)through whole exome sequencing(WES)to 18 patients with PCNSL.Methods:Tumor tissues from 18 patients with diffuse large B-cell lymphoma who were diagnosed with PCNSL in Department of Hematology,Lanzhou University Second Hospital from September 2018 to December 2020 and had normal immune function,no history of HIV or immunosuppressant therapy were collected.High-throughput-based WES was performed on the tumor tissues,with an average sequencing depth of＞100 x.After data processing and bioinformatics analysis of sequencing results,the mutation maps and mutation characteristics of 18 PCNSL patients were obtained.Results:Obvious somatic mutations were detected in all 18 patients.The median number of somatic mutations was 321.Missense mutations were most prominent(accounting for about 90％),and the mutation type was dominated by C＞T(50.2％),reflecting the age-related mutation pattern.Among the top 15 frequently mutated genes,PSD3,DUSP5,MAGEB16,TELO2,FMO2,TRMT13,AOC1,PIGZ,SVEP1,IP6K3,and TIAM1 were the driver genes.The enrichment results of driver gene pathways showed that RTK-RAS,Wnt,NOTCH,Hippo and Cell-Cycle pathways were significantly enriched.The tumor mutation burden was between 3.558 48/Mb and 8.780 89/Mb,and the average was 4.953 32/Mb,which was significantly higher than other cancer research cohorts in the TCGA database.Conclusions:PCNSL occurs somatic missense mutations frequently,mainly point mutations,and the mutation type is mainly C＞T.The driver genes are mainly involved in RTK-RAS,Wnt,NOTCH and Hippo pathways,indicating that the above pathways may be related to the pathogenesis of PCNSL.PCNSL has a significantly high tumor mutation burden,which may explain the efficacy of PD-1 inhibitors in PCNSL.
基金项目
甘肃省自然科学基金(22JR11RA053)
国家自然科学基金(82260041)
血液学淋巴瘤疾病发展科研基金(KMhermart 0805006)
NETL
NSTL
维普
万方数据