Role of the Fyn −93A>G polymorphism (rs706895) in acute rejection after liver transplantation

The tyrosine kinase Fyn phosphorylates tyrosine residues on key targets involved in early T-cell signal transduction. T-cell signal transduction is one essential step for acute transplant rejection. The aim of this study was to evaluate the association of Fyn −93A>G single nucleotide polymorphism (SNP) (rs706895) with the susceptibility to acute rejection episodes in liver transplantation. In total, 72 liver transplant recipients with one biopsy proven acute rejection (S-BPAR), 56 with multiple BPAR (M-BPAR), 105 without BPAR (No-BPAR), and 145 healthy controls were enrolled in this case-control study. The SNP was genotyped by polymerase chain reaction–allele specific restriction enzyme analysis (PCR–ASRA) and was analyzed for a recessive and a dominant model. The Fyn −93G allele exhibits in healthy controls a statistically significant lower frequency than in liver recipients (18% vs. 24%; p = 0.046) or in liver recipients with BPAR (18% vs. 27%; p = 0.017). However, the genotype and allele frequencies of the Fyn −93A>G SNP demonstrate no significant differences between recipients with acute rejection episodes (S-BPAR and M-BPAR) and No-BPAR recipients. Thus our results provide no evidence that the Fyn −93A>G SNP contributes to the susceptibility to acute liver transplant rejection in a Caucasian population.     

c-myb在肝细胞癌组织中的表达及临床意义

目的 研究c-myb基因在HCC组织中的表达,探讨其在HCC发生、发展中的作用及临床意义.方法 应用免疫组织化学法检测55例HCC组织、55例癌旁组织、12例肝硬化组织和11例正常肝组织中c-myb蛋白表达情况.结果 癌组织相对于正常的肝组织,癌旁组织相对于肝硬化组织,c-myb蛋白的表达明显增高(P=0.000).结论 提示,c-myb过表达是HCC发病中的早期事件,在HCC的发生、发展中可能起重要作用,检测c-myb的表达具有一定的临床意义.     

c-myb对胚胎干细胞体外造血分化及定型的影响

目的　通过体外胚胎干细胞培养体系对ES细胞进行c- myb等位基因打靶,建立c -myb 及c -myb ES细 胞模型的基础上,探讨转录因子c- myb在造血定型和分化中的作用。方法　通过体外ES细胞去除LIF半固体介质EBs的 造血分化体系,采用甲基纤维素克隆形成分析和real timePCR观察c- myb 及c -myb ES细胞,比较分析其不同分化过 程及阶段中造血各系形成和相关基因表达变化。结果　c -myb 及c -myb ES胚胎体(EBs)大小及形态相似,c -myb ESEBs形成显著多于c -myb 。c -myb 组CFU- E出现在第6天,高峰为第8天;c- myb 组也有相似的改变,但其 CFU- E数目少于c -myb 。c -myb 组CFU- M高峰为第7天;c- myb 也有相似的改变,但其CFU- M数目高于c- myb 。c -myb CFU -GM出现在第7天,高峰为第12天,而c -myb 未见CFU -GM形成。real timePCR分析显示,c -myb 及 c- myb β globin,zeta globin,Lys,C- fms基因表达无显著变化。结论　低水平的c -myb不影响祖细胞的扩增,但影响其 终末分化。低水平的c -myb表达在造血定型中对红系的发育具有一定的影响,而对巨噬细胞的发育成熟无明显影响。 c -myb的表达水平对造血分化相关基因的表达没有明显的影响。     

血小板疾病中原癌基因c-myc,c-myb的研究进展

原癌基因c-myc和c-myb对造血系统有重要的调节作用.c-myc基因表达的变化与细胞增殖、分化状态有关,其表达产物在调节细胞生长、分化或恶性转化中发挥作用.c-myb参与转录,影响细胞增殖、分化、凋亡.近年来,随着分子生物学、分子免疫学、细胞生物学等相关技术的日趋成熟,原癌基因c-myc、c-myb在造血调控中的研究逐渐增多.研究发现,巨核-红系祖细胞的定向分化及血小板的异常与其表达水平有关.常见的血小板疾病见于血小板减少症、血小板增多症等,此类疾病的病因和发病机制尚未明T.本文就c-myc和c-myb基因的结构、功能及其在血小板疾病中的表达水平与意义作-综述.     

c-myb、Bax蛋白在子宫内膜癌中的表达及意义

目的 探讨c-myb、Bax蛋白在子宫内膜癌中的表达和意义。方法 应用免疫组化SP法和TUNEL技术对68例子宫内膜样腺癌组织和42例正常子宫内膜组织中c-myb、Bax蛋白表达和细胞凋亡指数进行检测,结合临床病理指标进行分析。结果 c-myb、Bax在子宫内膜癌组织中的阳性表达率高于正常子宫内膜组织（P<0.05 ）。c-myb、Bax在分化程度越低的子宫内膜癌组织中的表达越高,在Ⅲ、Ⅳ期子宫内膜癌中的表达高于Ⅰ、Ⅱ期,差异有统计学意义（P<0.05）。子宫内膜癌组织的细胞凋亡指数高于正常子宫内膜组织,且子宫内膜癌细胞分化程度越低,细胞凋亡指数越高。Bax表达与子宫内膜癌细胞凋亡指数呈正相关（r=0.529, P<0.05）,而c-myb表达与子宫内膜癌凋亡指数无相关性（P>0.05）。结论 子宫内膜癌中存在c-myb、Bax蛋白的高表达,c-myb参与肿瘤细胞的增殖分化调节,Bax调节肿瘤细胞凋亡,两者可作为判断子宫内膜癌恶性行为和预后的指标。     

C-myb、PKCa在脑胶质瘤侵袭作用中的相关性研究

目的研究脑胶质瘤侵袭性生长过程中,C-myb的作用及其与蛋白激酶Ca之间的相互关系.方法Wistar大鼠35只,随机分为实验组(30只)和对照组(5只).实验组每只大鼠于右侧大脑皮质运动区种植C6胶质瘤细胞10μl(3×107个/μl),对照组则注入10μl生理盐水,于术后10天将大鼠全部处死取材,进行大体观察、HE染色及免疫组织化学检查,并将实验组侵袭性量化为0～Ⅳ级,分别检查对照组和实验组肿瘤侵袭性中,各组C-myb、PKCa的表达,并对其进行评分.结果1.实验组大鼠均可见肿瘤生长,其中28只表现为侵袭0～Ⅳ级;2.C-myb表达越强,脑胶质瘤侵袭的级别越高,呈正相关(P＜0.01);3.肿瘤区C-myb与PKCa表达在肿瘤各级中均为高度一致;4.在肿瘤0～Ⅳ级侵袭中,瘤周区及边缘区的C-myb、PKCa二者表达评分密切相关(P＜0.05);5.对照组中,C-myb、PKCa均为阴性表达.结论本组资料表明,C-myb是脑胶质瘤侵袭性的重要癌其因,脑胶质瘤的侵袭性生长是临床术后复发的根本原因.     

C-Jun is Induced to High Continuous Expression During Differentiation of Hematopoietic Cells and is Regulated Independently from C-Fos

The c-jun proto-oncogene is usually expressed at a low level in most cell types but is induced rapidly and transiently in response to stimuli. The present results show that stimulation of U-937 cells to macrophage differentiation by a phorbol ester or vitamin D₃ induced a continuous high level expression of c-jun mRNA and protein. High level expression of c-jun mRNA was also observed in various other human differentiated hematopoietic cells, represented by normal macrophages, HL-60 promyelocytic cells differentiated towards macrophages or granulocytes and in myeloma, but not in immature cell lines. These results might suggest a role of c-jun in the differentiation of several hematopoietic lineages. In U-937, a differential regulation of c-jun and c-fos was demonstrated both with respect to kinetics and to the level of regulation. Furthermore, in subclones of U-937, where maturation and growth arrest could be separated, c-jun was induced in the absence of c-fos and vice versa. Expression of c-jun and c-fos mRNA correlated with maturation and growth arrest, respectively, in these clones. cAMP generating agents, which induced c-jun and c-fos, did, however, not induce terminal differentiation, indicating that other signals, e.g. those associated with down-regulation of c-myb and c-myc, are also required.     

转录因子c-myb及肝脏激活蛋白对α1(Ⅰ)胶原基因在肝星状细胞中表达的调控作用

目的 了解激活的ＨＳＣ中ｃ－ｍｙｂ及肝脏组织特异的转录因子－肝脏激活蛋白（ｌｉｖｅｒ ａｃｔｉｖａｔｏｒｐｒｏｔｅｉｎ，ＬＡＰ）在α１（Ｉ）基因表达调控中的作用。方法 采用链霉蛋白酶，胶原酶原位灌注、Ｎｙｃｏｄｅｎｚ密度梯度离心分离大鼠ＨＳＣ，并进行体外培养使之激活，构建含人α１（Ｉ）胶原基因启动子片段（－８０４～＋１４５或－８０４～＋２２２碱基）的荧光素酶报告基因质粒，用构建的报告基因质粒与ｃ－