中枢神经系统原发性弥漫大B细胞淋巴瘤中EZH2蛋白的表达和意义  

Overexpression of histone methyltransferase EZH2 in primary diffuse large B-cell lymphoma of the central nervous system and its significance

作　　者：郭双平[1,2] 白庆咸[3] 王映梅[1,2] 刘杨[2] 

机构地区：[1]第四军医大学病理学教研室,西安710032 [2]第四军医大学西京医院病理科,西安710032 [3]第四军医大学西京医院血液科,西安710032

出　　处：《临床与实验病理学杂志》2016年第6期630-634,共5页Chinese Journal of Clinical and Experimental Pathology

基　　金：国家自然科学基金(81472597)

摘　　要：目的 探讨组蛋白甲基转移酶EZH2在中枢神经系统原发性弥漫大B细胞淋巴瘤（diffuse large B-cell lymphoma,DL-BCL）中的表达及意义。方法 采用免疫组化法检测33例中枢神经系统原发性DLBCL中EZH2的表达,分析其与临床病理学特征之间的关系。结果 33例中枢神经系统原发性DLBCL中20例为中心母细胞型,4例为免疫母细胞型,6例为中间型细胞组成,3例为间变亚型。免疫表型上,25例为非生发中心B细胞样型（non-germinal centre B-cell-like,non-GCB）型,8例为生发中心B细胞样型（germinal centre B-cell-like,GCB）型。全部病例均过表达EZH2蛋白,但不同形态学和免疫表型的DLBCL中EZH2蛋白表达无差异,28例80%~100%肿瘤细胞呈EZH2蛋白强阳性,5例50%~79%肿瘤细胞呈EZH2蛋白中等程度~强阳性。24例患者获得随访,中位生存时间为12.5个月,其中Non-GCB型和GCB型患者的中位生存时间分别为11个月和25个月,EZH2蛋白表达与患者预后无相关性。结论 EZH2在中枢神经系统原发性DLBCL中过表达,提示将来可能用EZH2抑制剂治疗这种高度恶性DLBCL。Purpose Primary diffuse large B-cell lymphoma （DLBCL） of the central nervous system （CNS） is a rare subtype of non- Hodgkin lymphoma. The histone methyltransferase EZH2 was reported to be involved in tumorigenesis of systemic DLBCL recently; however, no reports of EZH2 expression was found in primary CNS DLBCL. Methods Immunohistochemical staining （IHC） was used to detect the expression of EZH2 in 33 cases of primary CNS DLBCL. The relationship between EZH2 expression and the clinicopathological features of primary CNS DLBCL were analyzed. Results Morphologically, the tumor ceils resembled to centroblasts in 20 cases, immunoblasts in four cases, intermediate cells in six cases, and anaplastic variants in three cases. Immunophenotypically, 25 cases were non-GCB type and eight cases were GCB subtype. EZH2 overexpressed in all 33 cases. EZH2 overexpressed in 80 - 100% tumor cells with uniformly strong intensity in 28 cases, and in 50% -79% tumor cells with moderate to strong intensity in five cases. The follow-up information was obtained in 24 patients, with a median survival time of 12.5 months. The median survival time for the patients of non-GCB and GCB subgroups were eleven and twenty-five months, respectively. No association was found between the level of EZH2 expression and outcome of patients. Conclusion The anaplastic variant of primary CNS DLBCL is reported fnr the first time. Overexpression of EZH2 in primary CNS DLBCL suggests the possibility of using EZH2 inhibitor to treat this aggressive lymphoma in the future.

关 键 词：中枢神经系统肿瘤 弥漫大B细胞淋巴瘤 组蛋白甲基转移酶EZH2 免疫表型 预后 

分 类 号：R739.4[医药卫生—肿瘤] R733[医药卫生—临床医学]