非小细胞肺癌组织中FADD基因的表达及突变分析

背景与目的:Fas相关死亡结构域蛋白(Fas-associateddeathdomain,FADD)是细胞凋亡信号转导过程中重要的转接蛋白,研究表明其异常表达可能与肿瘤关系密切,但有关FADD与人非小细胞肺癌(non-smallcelllungcancer,NSCLC)的研究尚鲜见报道。本研究检测FADD基因在NSCLC中的表达及突变情况,以探讨该基因在肺癌发生发展中的作用及机制。方法:采用聚合酶链反应-单链构象多态性分析(polymerasechainreactionandsingle-strandconformationpolymorphism,PCR-SSCP)以及免疫组织化学法(immunohistochemistry,IHC)分别检测62例NSCLC及13例癌旁非癌肺组织中FADD基因突变及蛋白表达情况,原位杂交法(insituhybridization,ISH)检测其中30例肺癌组织FADDmRNA表达水平,原位末端标记法(terminaldeoxynucleotidyltransferase-mediateddUTP-biotinnicklabeling,TUNEL)检测62例NSCLC中的癌细胞凋亡。结果:PCR-SSCP检出62例NSCLC组织中有4例N2期组织发生FADD基因突变,提示FADD基因突变与淋巴结转移有关。IHC结果显示:NSCLC组织中FADD蛋白阳性率为80.6%(50/62),其阳性表达程度与肿瘤分化程度呈显著正相关(rs=0.411,P<0.01),癌组织中FADD阳性表达程度高于癌旁非癌肺组织(P<0.05)。ISH结果显示:FADDmRNA阳性表达与相应组织FADD蛋白阳性     

肝癌中Fas相关死亡区蛋白与细胞凋亡相关性初探

目的 :研究肝癌中Fas相关死亡区蛋白 (FADD)与细胞凋亡间的相关性。方法 :采用原位末端标记及免疫组化法分别检测肝癌中细胞凋亡及FADD蛋白表达。结果 :78例肝癌中 2 0例 (2 5 6 % )表达FADD蛋白 ,显著低于癌旁非癌肝组织 (10 16 ,6 2 .5 % ,P <0 .0 5 )。 12 36 (33 3% )分化中等良好的HCC中FADD表达 ,略高于分化差的HCC(8 4 2 ,19% ,P >0 .0 5 )。Ⅰ Ⅱ级HCC中 ,16例为FADD阳性 (16 4 2 ,38 1% ) ,而Ⅲ Ⅳ级HCC中阳性率仅为 11 1% (P <0 .0 5 )。所有标本中均能检测到细胞凋亡 ,在FADD蛋白中等阳性和强阳性的HCC中 ,细胞凋亡程度较高 ,与FADD表达弱阳性或阴性的HCC相比P <0 .0 5 ,癌旁组织中FADD表达与细胞凋亡无关 (P >0 .0 5 )。结论 :FADD表达降低在肝癌发生中起作用 ,且与肝癌细胞凋亡相关     

PCR-SSCP法检测非小细胞肺癌中FADD基因突变的研究

目的检测Fas相关死亡结构域蛋白(Fasassociateddeathdomainprotein,FADD)基因在人非小细胞肺癌(nonsmallcelllungcancer,NSCLC)中的突变情况,以探讨该基因在肺癌发生发展中的作用及机制。方法采用聚合酶链反应-单链构象多态性分析(polymerasechainreactionandsinglestrandconformationpolymorphism,PCRSSCP)检测74例NSCLC原发灶癌组织及13例癌旁正常肺组织中FADD基因突变情况。结果74例NSCLC组织中检出5例发生FADD基因突变,FADD基因突变与癌的淋巴结转移呈显著正相关(rs=0.378,P=0.001),与其他临床病理特征无关。结论NSCLC中存在着FADD基因突变。FADD基因突变在NSCLC的发生发展中可能起着重要作用。     

肝癌中Fas相关死亡区蛋白与细胞凋亡相关性初探

目的：研究肝癌中Fas相关死亡区蛋白(FADD)与细胞凋亡间的相关性。方法：采用原位末端标记及免疫组化法分别检测肝癌中细胞凋亡及FADD蛋白表达。结果：78例肝癌中20例(25.6％)表达FADD蛋白，显著低于癌旁非癌肝组织(10／16，62.5％，P＜0.05)。12／36(33.3％)分化中等良好的HCC中FADD表达，略高于分化差的HCC(8／42，19％，P＞0.05)。Ⅰ／Ⅱ级HCC中，16例为FADD阳性(16／42，38.1％)，而Ⅲ／Ⅳ级HCC中阳性率仅为11.1％(P＜0.05)。所有标本中均能检测到细胞凋亡，在FADD蛋白中等阳性和强阳性的HCC中，细胞凋亡程度较高，与FADD表达弱阳性或阴性的HCC相比P＜0.05，癌旁组织中FADD表达与细胞凋亡无关(P＞0.05)。结论：FADD表达降低在肝癌发生中起作用，且与肝癌细胞凋亡相关。     

非小细胞肺癌COX-2蛋白表达及与bcl-2相关性

 目的　探讨非小细胞肺癌 (NSCLC)环氧化酶 2 (cyclooxygenase 2 ,COX 2 )蛋白表达的临床意义及与bcl 2的关系。方法　免疫组织化学法检测 5 3例NSCLC癌组织及配对癌旁正常组织COX 2蛋白的表达及定位 ,Western印迹法半定量检测COX 2蛋白表达水平 ;免疫组织化学法检测癌组织bcl 2蛋白表达。结果　肺癌组织COX 2蛋白表达高于癌旁正常组织 (P <0 .0 1) ,腺癌高于鳞癌 (P <0 .0 5 ) ,但与患者的年龄、性别、TNM分期及肿瘤组织的分化程度无明显相关 (P >0 .0 5 )。COX 2与bcl 2蛋白表达相关 (P <0 .0 5 )。结论　COX 2在肺癌组织尤其是肺腺癌中表达上调 ,COX 2与bcl 2在NSCLC发展中可能起协同作用。     

非小细胞肺癌bax蛋白的表达及意义

目的 :探讨凋亡相关基因bax在人非小细胞肺癌 (non smallcelllungcarcinoma ,NSCLC)组织中的表达情况及其与肺癌临床病理特征和预后的关系。方法 :用免疫组织化学SABC法检测 6 8例NSCLC中bax蛋白的表达水平 ,用TUNEL法检测其中的细胞凋亡情况。研究对象 :鳞癌 38例 ,腺癌 30例 ,同时检测 11例正常肺组织作为对照。结果bax蛋白在肺癌组织中的阳性表达率为 5 4 4 1% ,正常肺组织为 10 0 % ,两者差异有极显著性 (P <0 .0 1) ;在鳞癌中的阳性表达率为 39 4 7% ,小于腺癌的73 33% (P <0 0 1) ;bax的表达与T和N情况、临床分期、年龄、性别和是否吸烟无关。NSCLC组织的凋亡指数 (AI)为 1 79± 0 5 1,小于正常肺组织的 14 33± 5 6 2 (P <0 0 5 )。在NSCLC中 ,bax蛋白表达阴性者生存时间长于阳性者 (P <0 0 5 )。结论 :bax蛋白的表达与非小细胞肺癌的组织类型和预后相关 ,并通过对细胞凋亡的调控参与了肺癌的发生、发展。     

人非小细胞肺癌中蛋白激酶CβⅠ的表达及细胞凋亡与预后关系的研究

目的探讨人非小细胞肺癌中蛋白激酶CβⅠ(PKC-βⅠ)的表达及细胞凋亡在肺癌发生、发展和预后中的作用.方法应用免疫组织化学LSAB法和TUNEL法检测119例人非小细胞肺癌组织、癌旁肺组织和32例肺良性疾病肺组织中PKC-βⅠ的表达和凋亡水平.结果(1)NSCLC组织中PKC-βⅠ阳性表达率(82.27%)显著高于癌旁肺组织(62.85%)和肺良性疾病肺组织(50.47%)(P＜0.05),癌旁肺组织中PKC-βⅠ阳性表达率显著高于肺良性疾病肺组织(P＜0.05).NSCLC组织中凋亡指数(5.27%)明显低于肺良性疾病肺组织(15.84%)(P＜0.05).(2)NSCLC组织中PKC-βⅠ阳性表达率与肺癌临床病理生理特征无明显关系(P＞0.05).NSCLC细胞凋亡水平与肺癌pTNM分期、原发肿瘤大小及淋巴结转移状态有密切关系(P＜0.05),而与肺癌细胞分化程度、组织学类型、患者性别和年龄等均无明显关系(P＞0.05).(3)PKC-βⅠ阳性表达率与细胞凋亡水平呈显著负相关(P＜0.01).(4)PKC-βⅠ高表达组肺癌患者术后5年生存率(7.37%)显著低于低表达组患者(37.06%)(P＜0.01).肺癌细胞凋亡高水平组患者5年生存率(39.24%)显著高于凋亡低水平组患者(6.14%)(P＜0.01).结论监测肺癌患者PKC-βⅠ的表达和细胞凋亡指数有助于预测患者预后,指导术后多学科综合治疗.     

胃癌及癌旁组织Fas蛋白和CD44V6蛋白的表达及其临床意义

目的　探讨Fas蛋白、CD44V 6蛋白在胃癌及癌旁组织的表达及其临床意义。方法　采用免疫组化SP法分别检测5 7例胃癌组织 ,5 7例癌旁组织和 2 0例正常胃黏膜组织中Fas蛋白、CD44V 6蛋白的表达。结果　 5 7例胃癌组织中Fas蛋白表达的阳性率为 35 .0 9% ,5 7例癌旁组织为 70 .18% ,正常胃黏膜为 85 .0 0 % ,胃癌组织与癌旁组织 ,正常胃黏膜组织Fas蛋白的表达比较均有非常显著性差异 (P <0 .0 1)。CD44V 6蛋白的表达 ,胃癌组为 66.67% ,癌旁组为 2 2 .81% ,正常胃黏膜为 10 .0 0 % ,胃癌组织与癌旁组织 ,正常胃黏膜组织之间的CD44V 6蛋白的表达均有非常显著性差异 (P <0 .0 1)。结论　Fas蛋白、CD44V 6蛋白的表达对阐明胃癌的发生机制、预后和转移均有重要意义     

肝癌组织中凋亡信号蛋白的表达及其临床意义

[目的]分析凋亡信号蛋白(FADD、TRADD、FasL、Fas和NFκB)在人类肝癌组织中的表达及其临床意义。[方法]采用Westernblot法检测肝癌组织中上述5种凋亡信号蛋白的表达情况。[结果]在35例HCC标本中,FADD、TRADD、FasL、Fas和NFκB蛋白表达分别为37.14%(13/35)、68.57%(24/35)、68.57%(24/35)、60%(21/35)和77.14%(27/35)。其中,Fas蛋白表达随肿瘤增大而下降,同肿瘤大小之间差异有显著性(P<0.05)。FADD和Fas两蛋白表达随肿瘤恶性程度增高,而明显下降,与病理分级间差异有显著性(P<0.01,P<0.05)。TRADD和Fas蛋白表达同甲胎蛋白水平呈正相关(P<0.01)。各蛋白表达同肿瘤转移无关(P>0.05)。[结论]肝癌细胞可通过下调引起凋亡的信号蛋白的表达,如Fas,FADD;和上调引起存活信号蛋白的表达,如TRADD,NFκB等机制的协同作用,来逃避凋亡的发生,从而达到维持自身稳定的目的,这对肝癌的发展起重要作用。     

survivin在非小细胞肺癌中的表达及其与细胞凋亡的关系

目的:检测非小细胞肺癌(NSCLC)中survivin表达水平及凋亡指数(AI)大小,探讨其临床病理意义、在肺癌发生和进展中的作用以及二者可能存在的相关性.方法:应用免疫组织化学法检测108例NSCLC,60例癌旁肺组织survivin表达情况,原位末端标记法(TUNEL)检测AI大小.结果:survivin在NSCLC中表达高于癌旁肺组织(P＜0.05),NSCLC 中AI小于癌旁肺组织(P＜0.05),survivin表达及AI均与肿瘤组织的分化程度、TNM分期及淋巴结转移有关(P＜0.05),survivin表达与AI呈负相关(P＜0.05).结论:细胞凋亡水平异常可能在肺癌发生发展中起重要作用,survivin可能通过抑制细胞凋亡参与了肺癌的发生、发展.     

Farnesyltransferase inhibitors: antineoplastic properties, mechanisms of action, and clinical prospects

Farnesyltransferase (FTase) inhibitors are among the current wave of molecularly targeted anti-cancer agents being used to attack malignancy in a rational manner. A large body of preclinical data indicates that FTase inhibitors block cancer cell proliferation through both cytostatic and cytotoxic effects. Interestingly, FTase inhibitors have rather limited effects on normal cell function, suggesting that they may target unique aspects of cancer cell pathophysiology. The development of FTase inhibitors was predicated on the discovery that the Ras oncoproteins must be post-translationally modified to transform cells. However, recent work indicates that the anti-neoplastic effects of FTase inhibitors depend on altering the post-translational modifications of non-Ras proteins as well. In particular, a critical target protein that responds to FTase inhibition by blocking tumor cell growth is RhoB, an endosomal Rho protein that functions in receptor trafficking. In this review, we survey the biological foundations for the clinical development of FTase inhibitors, and consider some of the latest mechanistic studies that reveal how these agents affect cellular physiology.     

Targeting tumor vasculature with homing peptides from phage display

Tumor vasculature expresses a number of molecular markers at much lower levels than those seen in the blood vessels of normal tissues, and in some cases, such markers are undetectable. The presence of these markers relates to angiogenesis; the same markers are shared by all blood vessels undergoing angiogenesis. The endothelial cells, pericytes and smooth muscle cells, and the vascular extracellular matrix in angiogenic vessels can each express such markers. Molecularly, they represent vascular growth factor receptors, cell adhesion proteins and their receptors. Screening of phage display libraries for peptides that home to tumor vasculature when injected into mice has recently provided a new tool for analyzing the distinguishing features of tumor vasculature. Tumor-homing peptides isolated in this manner, as well as an antibody against a form of fibronectin expressed in tumor blood vessels, have been found to serve as targeting devices to concentrate drugs and other therapeutic materials to tumors in in vivo models. Such a targeting strategy can therefore potentially improve the efficacy of drugs and reduce their side effects.     

Identification of EBV transforming genes by recombinant EBV technology

Epstein-Barr virus (EBV) is able to infect primary B-lymphocytes but usually does not proceed to replicate more virions. Instead, EBV persists as an incomplete virus and expresses 12 gene products that transform the growth of these cells into continuously proliferating lymphoblastoid cell lines. Because EBV is associated with several human malignancies, there is intense interest in delineating the molecular functions of these EBV gene products in transformation. This review focuses on the recombinant EBV technologies that have been developed to introduce specific mutations into EBV and test the functions of these EBV genes in primary B-lymphocyte growth transformation.     

Matrix metalloproteinases in tumor invasion and metastasis

Extensive work on the mechanisms of tumor invasion and metastasis has identified matrix metalloproteinases (MMPs) as key players in the events that underlie tumor dissemination. Studies using natural and synthetic MMP inhibitors, as well as tumor cells transfected with cDNAs encoding the MMPs characterized thus far have provided compelling evidence that MMP activity can induce or enhance tumor survival, invasion and metastasis. Because of the ability of MMPs to degrade extracellular matrix (ECM) proteins, the principal mechanism whereby MMPs promote tumor development has been thought to be the proteolytic breakdown of tissue barriers to invasion and the associated facilitation of circulating tumor cell extravasation. However, recent evidence stemming from the use of novel experimental approaches indicates that MMPs do not play a major role in the process of extravasation itself. Rather, they appear to promote intravasation (the process of penetrating the circulation following invasion of blood vessels) and regulate the relationship between tumor cells and host tissue stroma subsequent to extravasation. In addition, the discoveries that a growing number of proteolytically active MMPs may localize to the cell surface in association with adhesion receptors, and that MMP substrates include latent cytokines and growth factors, provide a new conceptual framework for the mechanisms whereby MMPs influence tumor behavior.     

New aspects of integrin signaling in cancer

Members of the integrin family of cell adhesion receptors influence several important aspects of cancer cell behavior, including motility and invasiveness, cell growth, and cell survival. Engagement of integrins with extracellular matrix (ECM) proteins can activate members of the Rho-family of small GTPases; conversely, Rho- and Ras-family proteins can influence the ability of integrins to bind their ligands. These events impinge on the control of cell motility, and ultimately on invasive and metastatic behavior. Integrin engagement with ECM also has important effects on cell survival, particularly for cells of epithelial origin. In some cases, specific integrins have selective effects on the efficiency of signal transduction in cell survival pathways.     

Role of LMP1 in immune control of EBV infection

The Epstein-Barr virus (EBV) encoded latent membrane protein (LMP1) plays a crucial role in the long-term persistence of this virus within the cells of the immune system. Not only is this protein critical for the transformation of resting B cells by EBV, it also displays pleiotropic effects on various cellular proteins expressed in the host cell. These include up-regulation of expression of B cell activation antigens, adhesion molecules and various components of the antigen processing pathway. Here we discuss how LMP1 acts like an expression 'switch' which, depending on the stage of EBV infection, manoeuvres various pathways that either modulate the immune system towards or against its survival.     

腹部压块对膈肌运动影响的研究

目的 :研究腹部压块对膈肌运动的影响。方法 :选择拟行立体适形放疗患有肺癌或肝脏肿瘤的患者 2 0例。按治疗体位仰卧于体部立体放疗定位负压袋内 ,待患者呼吸平稳后 ,将灯光野的中心点置于膈顶运动的最低点 ,在膈肌运动至最高位时拍摄照片 ,测量膈肌运动的最大幅度 ;然后 ,将心形腹部压块放置于患者剑突下 ,并用定位框架的腹带交叉固定 ,按压程度以不引起患者呼吸困难或其他不适为标准 ,5min后按上述方法再次测量膈肌运动的最大幅度。结果 :2 0例患者未加腹部压块的运动幅度为0 6 2～ 2 6 7cm ,平均 (1 4± 0 6 4)cm ,加腹部压块后的膈肌运动幅度为 0 2 8～ 2 0 8cm ,平均 (1 0±0 5 5 )cm ,加腹部压块后膈肌运动幅度平均减小 (0 4± 0 34)cm ,P =0 0 0 0。加腹部压块后 90 % (18/2 0 )的患者膈肌运动幅度受到不同程度的限制 ,但有 10 % (2 /2 0 )的患者膈肌运动幅度增加。结论 :腹部压块可使大部分患者膈肌运动的幅度减小 ,但少部分患者例外 ,即腹部压块并不能使所有膈肌周围肿瘤的照射容积减少。建议在制定放射治疗计划前应预先进行测量和评价     

ABCG2在肺癌中表达的定量研究

目的 观察ABCG2在肺癌和癌周肺组织的表达,从量化角度阐明其在肺癌组织中表达的病理学意义.方法 常规石蜡包埋、HE切片确诊,用免疫组化SP法检测ABCG2在肺癌和癌周肺组织的定位和表达,用LeicaQ500MC图像分析系统对其表达强度进行定量分析,并用表达的阳性单位(positive unit PU)反映其表达强度.结果 ABCG2蛋白在肺癌和癌周正常肺组织中的表达主要定位在细胞质和细胞膜.在癌周正常肺组织的支气管和细支气管上皮呈弥漫表达,腺上皮呈灶性表达;肺鳞癌和肺腺癌弥漫或大片表达,肺鳞癌表达的PU值高于肺腺癌(P＜0.001),肺大细胞癌和肺小细胞癌不表达,PU值接近于零.癌周肺组织表达的PU值高于各型肺癌(P＜0.05).ABCG2蛋白表达的PU值在肺癌原发灶和转移灶之间无差别(P＞0.05),且与肺癌患者的性别、年龄、转移和TNM分期未见明显相关性(P＞0.05),与肺癌分化程度有关(P＜0.001).分化程度越高,PU值越高,但高分化肺癌和癌周肺组织的表达PU值差异无显著性(P＞0.05).结论 ABCG2蛋白表达程度与肺癌类型及分化程度具有相关性,可能成为判断其指标之一.     

Telomerase and human tumorigenesis

Human cancer cells, unlike their normal counterparts, have shed the molecular restraints to limited cell growth and are immortal. Exactly how cancer cells manage this at the molecular level is beginning to be understood. Human cells must overcome two barriers to cellular proliferation. The first barrier, referred to as senescence, minimally involves the p53 and Rb tumor-suppressor pathways. Inactivation of these pathways results in some extension of lifespan. However, inactivation of these pathways is insufficient for immortalization. As normal cells undergo repeated rounds of DNA replication, their telomeres shorten due to the inability of traditional DNA polymerases to completely replicate the end of the chromosomal DNA. This shortening continues until the cells reach a second proliferative block referred to as crisis, which is characterized by chromosomal instability, end-to-end fusions, and cell death. Stabilization of the telomeric DNA through either telomerase activation or the activation of the alternative mechanism of telomere maintenance (ALT) is essential if the cells are to survive and proliferate indefinitely. Conversely, loss of telomere stabilization by an already-immortalized cell results in loss of immortality and cell death. Together this indicates that telomere maintenance is a critical component of immortality. In this review we attempt to describe our current understanding of the role of telomere maintenance in senescence, crisis, and tumorigenesis.     

Post-translational regulation of COX2 activity by FYN in prostate cancer cells

While increased COX2 expression and prostaglandin levels are elevated in human cancers, the mechanisms of COX2 regulation at the post-translational level are unknown. Initial observation that COX2 forms adduct with non-receptor tyrosine kinase FYN, prompted us to study FYN-mediated post-translational regulation of COX2. We found that FYN increased COX2 activity in prostate cancer cells DU145, independent of changes in COX2 or COX1 protein expression levels. We report that FYN phosphorylates human COX2 on Tyr 446, and while corresponding phospho-mimetic COX2 mutation promotes COX2 activity, the phosphorylation blocking mutation prevents FYN-mediated increase in COX2 activity.