PTEN、MLL基因在T淋巴母细胞淋巴瘤／白血病的表达及其意义

 目的　分析肿瘤抑制基因PTEN、混合系白血病（MLL）基因等在T淋巴母细胞淋巴瘤／白血病（T-LBL／ALL）的表达及意义。方法　选用76例T-LBL／ALL患者淋巴结存档蜡块,应用免疫组织化学EnVision法进行PTEN标记,用20例反应性增生淋巴结标本作正常对照。并用荧光原位杂交（FISH）技术检测MLL基因所在11q23染色体的断裂和扩增情况。结果　76例T-LBL／ALL中,PTEN的表达率为64.47 %（49／76）,低于淋巴结反应性增生的100 %（20／20）（χ2＝19.220,P＜0.05）。PTEN表达与临床分期、Ki-67、乳酸脱氢酶（LDH）呈负相关（P＜0.05）。76例T-LBL／ALL中,MLL基因发生11q23染色体断裂13例（17.11 %）,扩增18例（23.68 %）。MLL基因断裂组总体生存率（25.0 %）低于非断裂组（43.6 %）（χ2＝11.357,P＜0.05）。MLL基因扩增组总体生存率（17.1 %）低于非扩增组（42.7 %）（χ2＝4.533,P＜0.05）。结论　抑癌基因PTEN表达降低在T-LBL／ALL的发生发展中可能具有重要作用。MLL基因发生染色体11q23断裂和扩增有助于对T-LBL／ALL预后的判断,发生MLL基因断裂或扩增的T-LBL／ALL预后较差,提示MLL基因断裂或扩增可能为T-LBL／ALL的一种分子亚型。     

PTEN、MLL基因在T淋巴母细胞淋巴瘤/白血病的表达及其意义

Objective To investigate the significance and expression of PTEN, MLL in T lymphoblastic lymphoma/leukaemia(T-LBL/ALL). Methods Seventy-six cases of T-LBL/ALL were studied by using immunohistochemical EnVision method for PTEN. Fluorescence in-situ hybridization (FISH) for MLL gene (located on chromosome 11q23) was performed to detect its breakage and amplification. Results Among the 76 cases ofT- LBL/ALL, the positive rate of PTEN was 64.47 % (49/76), lower than that in reactivated lymphoid tissue (100 %, 20/20) (λ2= 19.220, P ＜0.05). PTEN expression was reversely correlated to theclinical stage, Ki-67 index and LDH level (P ＜0.05). Among the 76 cases, MLL gene with breakage of 11q23 was detected in 13 cases (17.11%), and amplification in 18 cases (23.68 %). Survival rate ot MLL gene breakage group was lower than that of non-breakage group (25.0 %, 43.6 %). Survival rate of MLL gene amplification group was lower than that of non-amplification group too (17.1%, 42.7 %). Both of breakage and amplification were related to prognosis ( λ 2 = 11.357, λ 2 = 4.533; P ＜0.05). Conclusion Anti-oncogene PTEN down-regulation may play an important role on the development and proceeding of T-LBL/ALL. MLL gene with breakage and amplification of 11q23 are helpful to predict prognosis of T-LBL/ALL. The case with MLL gene breakage and amplification of T-LBL/ALL may have a poor prognosis. It hints this group maybe a subtype of T-LBL/ALL.     

PTEN、MLL基因在T淋巴母细胞淋巴瘤/白血病的表达及其意义

Objective To investigate the significance and expression of PTEN, MLL in T lymphoblastic lymphoma/leukaemia(T-LBL/ALL). Methods Seventy-six cases of T-LBL/ALL were studied by using immunohistochemical EnVision method for PTEN. Fluorescence in-situ hybridization (FISH) for MLL gene (located on chromosome 11q23) was performed to detect its breakage and amplification. Results Among the 76 cases ofT- LBL/ALL, the positive rate of PTEN was 64.47 % (49/76), lower than that in reactivated lymphoid tissue (100 %, 20/20) (λ2= 19.220, P ＜0.05). PTEN expression was reversely correlated to theclinical stage, Ki-67 index and LDH level (P ＜0.05). Among the 76 cases, MLL gene with breakage of 11q23 was detected in 13 cases (17.11%), and amplification in 18 cases (23.68 %). Survival rate ot MLL gene breakage group was lower than that of non-breakage group (25.0 %, 43.6 %). Survival rate of MLL gene amplification group was lower than that of non-amplification group too (17.1%, 42.7 %). Both of breakage and amplification were related to prognosis ( λ 2 = 11.357, λ 2 = 4.533; P ＜0.05). Conclusion Anti-oncogene PTEN down-regulation may play an important role on the development and proceeding of T-LBL/ALL. MLL gene with breakage and amplification of 11q23 are helpful to predict prognosis of T-LBL/ALL. The case with MLL gene breakage and amplification of T-LBL/ALL may have a poor prognosis. It hints this group maybe a subtype of T-LBL/ALL.     

组蛋白甲基转移酶EZH2和MLL2在弥漫大B细胞淋巴瘤中的最新研究进展

弥漫大B细胞淋巴瘤（diffuse large B cell lymphoma,DLBCL）是最常见的非霍奇金淋巴瘤（non-hodgkin lymphoma）,并且是一组在临床表现、组织形态和预后等多方面具有很大异质性的恶性肿瘤,其发病机制错综复杂。近年来表观遗传学修饰在DLBCL的发生、发展中的重要作用是研究的热点。本文综述了近年来组蛋白甲基转移酶EZH2和MLL2在弥漫大B细胞淋巴瘤中的最新研究进展,为从表观遗传学的角度认识和治疗弥漫大B细胞淋巴瘤提供新认识。     

Dab2基因与肿瘤相关性的研究进展

人类Dab2基因具有多种生理功能,并在多种信号转导通路中起重要作用.研究表明,Dab2蛋白表达下调与人类多种恶性肿瘤的发生发展密切相关.Dab2已被认为是抑癌基因之一.文章对关于Dab2基因及其相关蛋白结构、功能的相关研究进行综述,探讨其在肿瘤发生发展的作用.     

急性白血病MLL基因重排检测的临床意义

 目的　研究混合谱系白血病（MLL）基因重排在急性白血病（AL）中的发生率、产生融合基因的常见类型及其临床意义。方法　采用多重巢式RT-PCR法对109例AL患者进行免疫表型检测,分析MLL基因重排阳性患者的临床特征。结果　109例AL中7例发生MLL基因重排,发生率为6.4 %,其中AML 4例（1例为M2,1例为M4,2例为M5）, ALL 3例,均为B-ALL。多重巢式RT-PCR检测到的融合类型为MLL-AF4、MLL-AF6、MLL-AF9、MLL-AF10、MLL-ENL。MLL基因重排阳性患者外周血WBC高于MLL基因重排阴性患者,差异有统计学意义（P＝0.019）。结论　多重巢式RT-PCR是检测MLL基因重排快速有效的方法。伴MLL基因重排的AL患者WBC较高,预后差。     

Disabled-2基因与肿瘤的相关研究

信号转导是一个十分精细、复杂的过程,参与细胞的增殖、分化、成熟和凋亡的每一步。在正常情况下人体组织中的Disabled-2蛋白(Dab2)参与细胞的信号转导使机体保持正常功能,而在有些情况下Dab2蛋白的缺失影响正常信号转导途径,从而细胞发生异型性变化、癌变。本文综述Dab2基因及其相关蛋白的结构、功能及与肿瘤发生机制,并对Dab2这个可能的抑癌基因作进一步探讨。     

Tiam1基因与肿瘤转移

Tiam1基因即T细胞淋巴瘤侵袭和转移诱导蛋白1，是普遍存在的鸟嘌呤核苷酸转换因子，存在于多种肿瘤细胞中，与肿瘤的侵袭和转移密切相关。     

急性粒—单核细胞白血病及急性单核细胞白血病MLL基因重排的检测

了解ＭＬＬ基因重排在急性粒－单核细胞白血病（Ｍ４）及急性单核细胞白血病（Ｍ５）中的发生率及其特点。方法用Ｓｏｕｔｈｅｒｎ印迹法对１０例Ｍ４及２７例Ｍ５患者进行ＭＬＬ基因重排的检测。结果共发现５例Ｍ５患者伴有ＭＬＬ基因异常,此组患者发病年龄轻,发病时白细胞数高,肝脾肿大明显,易并发中枢神经系统白血病,完全缓解率低,平均生存期短。结论ＭＬＬ基因重排在Ｍ５中发生率高,且此基因异常是预后不佳的标志。     

抑凋亡基因Bcl—2与肿瘤

抑凋亡基因Ｂｃｌ－２与肿瘤张力综述吴金生审校近年来，随着细胞凋亡（Ａｐｏｐｔｏｓｉｓ）概念的确立，人们对肿瘤的发生及发展有了新的认识。认为肿瘤的发生不仅与细胞过度增殖相关，也与细胞凋亡减少有关［１］。细胞凋亡又名细胞程序性死亡（Ｐｒｏ－ｇｒａｍｍｅｄ...     

RET 基因与肿瘤

RET 基因与人类多种肿瘤的发生密切相关,是一种重要的癌基因。RET 相关肿瘤的发病机制主要是 RET 基因突变和野生型 RET 基因的异常表达。激活的 RET 蛋白通过多种信号通路参与不同肿瘤细胞的增殖、凋亡、侵袭,影响肿瘤的发生发展。     

MLL2, Not MLL1, Plays a Major Role in Sustaining MLL-Rearranged Acute Myeloid Leukemia

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sox4基因在肿瘤中的作用机制及异常表达

近年的研究显示sox4基因在多种肿瘤组织中呈异常表达,与肿瘤的发生、发展及转移密切相关,其作用机制涉及对细胞的增殖、分化及凋亡等多方面的调控.深入研究该基因与肿瘤的关系,有望为研发肿瘤的特异性诊断标志和治疗靶点提供新的思路.