全外显子组测序筛选结外鼻型NK/T细胞淋巴瘤的致病基因研究

Extranodal NK/T-cell lymphoma, nasal type (ENKTCL-N) is a predominantly extranodal lymphoma characterized by vascular damage and destruction, prominent necrosis, cytotoxic phenotype and association with Epstain-Barr virus (EBV). Epidemiologically, ENKTCL-N is more prevalent in Asians, and the native American population of Central and South America. Little is known about the molecular pathogenesis of ENKTCL-N. Whole exome sequencing (WES) is a new technique which focuses on only the protein-coding portion of the genome. Thus, WES places many advantages of the emerging technologies into researchers' hands. Recent successes in using this technique have uncovered gene mutations in many kinds of tumors. WES is expected to provide the overall molecular abnormalities of a certain tumor for understanding diseases and to identify all the variants in an individual's genome for enabling personalized medicine based on one's genome. However, no research about ENKTCL-N by using WES has been reported in the literature yet. Therefore, this study is designed to find out the overall gene mutations using WES and choose 2～4 candidate key genes which may play an important role in the pathogenesis of ENKTCL-N. Then, we will do sequencing analysis and expression experiments to validate the mutation and expression of the candidate genes in a panel of paraffin-embedded samples and observe whether the candidate genes is related to malignant biological characteristics of ENKTCL, including tumor cell proliferation, invasion, spread, et al. Meanwhile, we will investigate the possible signal transduction pathways related to the candidate genes. The aim of this study is to find out possible candidate genes in the pathogenesis of ENKTCL-N and provide theoretical basis for molecular targeted therapy of ENKTCL-N.

结外鼻型NK/T细胞淋巴瘤（ENKTCL-N）是一组形态特殊、免疫表型独特、生物学行为呈高侵袭性的肿瘤，且与EB病毒感染高度相关。目前该肿瘤发生和演进的分子机制仍不清楚。全外显子组测序（WES）技术能检测出待测组织发生的所有外显子基因的突变，是目前研究致病基因突变机理较为理想的技术手段。WES用于肿瘤发病机制的研究已经取得了一些成就，但至今为止，国内外尚未见到WES用于NK细胞肿瘤的相关研究报道。本课题拟采用WES技术了解ENKTCL-N的整体基因突变情况，筛查出2～4个候选致病基因，进而对一组ENKTCL-N石蜡样本进行所筛查出的候选致病基因的测序分析及表达研究，观察有关致病基因与ENKTCL-N肿瘤细胞的增殖、侵袭及扩散等恶性生物学行为的关系，并研究可能与候选基因相关的信号通路，旨在寻找ENKTCL-N的致病基因，为该肿瘤的分子靶向治疗提供理论依据。

本课题研究分4个部分：（1）收集了20例鼻ENKTCL-N新鲜肿瘤组织和相应的外周血标本以及200例不同部位的ENKTCL-N石蜡包埋肿瘤组织样本；（2）完成了所收集样本的全基因组DNA的提取；（3）对2对ENKTCL-N样本进行了全外显子组测序及分析，筛选出了16个突变基因作为候选基因进行验证，其中包括涉及细胞粘附、分裂周期、增殖信号通路和离子通道等各方面的关键基因；同时对200例ENKTCL-N石蜡包埋组织进行基于PCR的Sanger测序，验证候选基因的突变情况，为下一步研究ENKTCL-N的分子机制奠定了基础；（4）对200例提供ENKTCL-N石蜡包埋肿瘤组织样本的患者进行了临床病理资料的收集和整理，并分析候选基因突变与ENKTCL-N的临床病理表现及预后的关系，综合分析所研究的基因在ENKTCL-N中的可能作用。本课题研究工作按时完成，但数据分析、整理及论文撰写等工作还在进行中。在该课题的资助下，截止至2013年12月，已发表3篇文章，其中SCI论文2篇，中文核心期刊1篇。