肿瘤坏死因子相关凋亡诱导配体(TRAIL)受体的表达及TRAIL的抗癌作用

肿瘤坏死因子相关凋亡诱导配体(TRAIL)可特异性杀伤肿瘤细胞同时赦免正常细胞。最近有报道，化疗可加强TRAIL诱导肺癌细胞凋亡。本研究意在观察TRAIL受体(TRAILR)的表达及TRAIL与顺铂、紫杉醇联合作用的抑癌性。     

TRAIL及其受体促凋亡机制与消化道肿瘤治疗的前景

肿瘤坏死因子相关凋亡诱导配体(TRAIL)因其选择性诱导肿瘤细胞凋亡的特点而受到关注.TRAIL促肿瘤细胞凋亡的机制及其受体对它的调控机制尚在探索中.目前,TRAIL及其受体已被广泛运用于消化道肿瘤的治疗研究中,不同的消化道肿瘤细胞株对TRAIL诱导的凋亡敏感性不同,某些细胞株对TRAIL耐药.克服肿瘤细胞对TRAIL的耐药,同时保护正常细胞免受伤害,充分发挥TRAIL选择性杀伤肿瘤细胞的优点,将使TRAIL在抗癌方面发挥积极的作用.     

端粒酶逆转录酶RNA干扰增加肿瘤坏死因子相关凋亡诱导配体活性

肿瘤坏死因子相关凋亡诱导配体（TNFα-related apoptosis-inducing ligand,TRAIL）为肿瘤坏死因子家族成员,与TNFα和Fas配体不同的是它仅诱导病毒感染细胞、转化细胞和肿瘤细胞凋亡,不引起炎症反应而杀伤正常细胞.TRAIL诱导大多数肿瘤细胞凋亡,但也有部分肿瘤细胞不敏感,且TRAIL对不敏感的肿瘤细胞有促增殖作用。     

TRAIL联合顺铂诱导胶质瘤细胞凋亡的机制

作为新型的抗肿瘤药物,肿瘤坏死因子相关凋亡诱导配体(TRAIL)已进入临床Ⅱ期试验阶段[1].研究发现,TRAIL可以诱导包括胶质瘤在内的多种肿瘤细胞发生凋亡,但大多恶性胶质瘤细胞对TRAIL耐药[2].前期研究的实验发现,原代培养的胶质瘤细胞对TRAIL诱导凋亡的敏感性不同,检测发现死亡受体(DR)5的表达量不同,并当TRAIL与化疗药物联合作用后可发挥协同作用[3～5].因此,本文进一步对TRAIL与化疗药物联合作用诱导胶质瘤细胞凋亡的机制进行研究,为TRAIL作为肿瘤治疗新药提供新的实验依据.     

高血压脑出血患者外周血中TRAIL及其受体的研究进展

高血压脑出血(hypertensive intracerebral hemorrhage,HICH)患者颅内血肿继发性脑水肿以及继发性脑血管痉挛等病理生理改变是导致预后欠理想的一个重要因素。其预后尚欠缺临床指标。肿瘤坏死因子相关凋亡诱导配体(TRAIL)是继肿瘤坏死因子(TNF)后发现的具有诱导细胞凋亡能力的细胞因子配体,在多种组织和细胞中广泛表达。其与HICH形成过程有一定的联系。但是TRAIL及其受体与HICH之后发生的机体各种病理生理改变以及预后的关系尚不明确。该文对HICH患者外周血中TRAIL及其受体的研究进展作一综述。     

γ-干扰素加强肿瘤坏死因子相关凋亡诱导配体抑制大肠癌细胞及其机制

有研究发现，部分肿瘤细胞对肿瘤坏死因子相关凋亡诱导配体(TRAIL)诱导的凋亡作用并不敏感，这限制了TRAIL在抗肿瘤治疗中的应用。有研究证实，γ-干扰素(IFN-γ)能增强TRAIL对肿瘤细胞的凋亡作用。我们以体外培养人大肠癌细胞株RKO为研究对象，探讨IFN-γ加强TRAIL的凋亡诱导作用，以及IFN-γ对TRAIL及其受体表达的调节作用。     

肿瘤坏死因子相关凋亡诱导配体与肝细胞凋亡的相关性

肿瘤坏死因子相关的调亡诱导配体是TNF家族成员之一,通过其死亡受体诱导凋亡.研究显示TRAIL/死亡受体途径参与多种肝脏病理过程,本文就TRAIL/死亡受体途径的特性、致凋亡的机制及与肝细胞凋亡关系的最新进展作一综述.     

肿瘤坏死因子相关的凋亡诱导配体及其受体与动脉粥样硬化

肿瘤坏死因子相关的凋亡诱导配体是肿瘤坏死因子家族新成员,它能和五种受体包括两种死亡受体和三种诱骗受体结合,分别能促进和抑制细胞凋亡。肿瘤坏死因子相关的凋亡诱导配体及其受体可表达于参与动脉粥样硬化的各种细胞如内皮细胞、平滑肌细胞及各种炎症细胞,发挥着促凋亡和抗凋亡的双重调节作用,直接或间接地参与了动脉粥样硬化的发生和发展。     

原代培养的恶性胶质瘤细胞表达死亡受体与TRAIL抵抗的关系

肿瘤坏死因子相关凋亡诱导配体( TRAIL)是肿瘤坏死因子超家族中的一员,作为肿瘤治疗的新药,在美国已进入临床Ⅱ期试验阶段[1].但由于在肿瘤治疗研究中,TRAIL一直存在治疗抵抗,因此,本文对原代培养的恶性胶质瘤细胞进行研究,通过观察TRAIL的两种受体——死亡受体(DR)4、DR5在恶性胶质瘤细胞中的表达,探讨在原代培养肿瘤细胞中存在的TRAIL抵抗问题.     

TRAIL联合顺铂诱导非小细胞肺癌细胞凋亡的作用

肿瘤坏死因子相关凋亡诱导配体(TRAIL)是体内天然的抗肿瘤药物,可由人体的免疫系统正常表达,目前在美国TRAIL已进入临床Ⅱ期研究阶段[1].本课题组在以往研究中发现,TRAIL在胶质母细胞瘤诱导凋亡过程中,发生凋亡抵抗而不能引起肿瘤细胞凋亡[2].因此,本文将研究TRAIL和化疗药物顺铂对非小细胞肺癌细胞联合诱导凋亡的作用,为TRAIL作为新药开发提供更进一步的理论依据,此方面研究国内还未见相关报道.     

Increased hepatotoxicity of tumor necrosis factor-related apoptosis-inducing ligand in diseased human liver

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis in tumor cells but not in most normal cells and has therefore been proposed as a promising antitumor agent. Recent experiments suggested that isolated primary human hepatocytes but not monkey liver cells are susceptible to certain TRAIL agonists, raising concerns about the use of TRAIL in cancer treatment. Whether TRAIL indeed exerts hepatotoxicity in vivo and how this is influenced by chemotherapeutic drugs or liver disease are completely unknown. Employing different forms of recombinant TRAIL, we found that the cytokine can induce proapoptotic caspase activity in isolated human hepatocytes. However in marked contrast, these different TRAIL preparations induced little or no cytotoxicity when incubated with tissue explants of fresh healthy liver, an experimental model that may more faithfully mimic the in vivo situation. In healthy liver, TRAIL induced apoptosis only when combined with histone deacetylase inhibitors. Strikingly, however, TRAIL alone triggered massive apoptosis accompanied by caspase activation in tissue explants from patients with liver steatosis or hepatitis C viral infection. This enhanced sensitivity of diseased liver was associated with an increased expression of TRAIL receptors and up-regulation of proapoptotic Bcl-2 proteins. CONCLUSION: These results suggest that clinical trials should be performed with great caution when TRAIL is combined with chemotherapy or administered to patients with inflammatory liver diseases.     

Tumour necrosis factor related apoptosis inducing ligand (TRAIL) induces hepatic steatosis in viral hepatitis and after alcohol intake

BACKGROUND AND AIMS: Tumour necrosis factor related apoptosis inducing ligand (TRAIL) induces apoptosis in transformed cells and is considered as an agent for cancer therapy. As there is evidence that TRAIL is also essential for apoptosis in animal models of liver injury, we investigated the role of TRAIL in viral hepatitis and after alcohol consumption. METHODS: Expression of TRAIL was determined by western blot analysis in the liver of patients with chronic hepatitis C virus (HCV) infection as well as in experimental acute adenoviral hepatitis and after alcohol intake in the liver of mice. To investigate the effect of FasL and TRAIL expression, we used low dose adenoviral gene transfer. Apoptosis and steatosis were assessed by TUNEL and fat red staining, and by caspase assays. RESULTS: TRAIL was overexpressed in the liver of patients with HCV associated steatosis while acute adenoviral hepatitis resulted in upregulation of TRAIL-DR5. In contrast with FasL, TRAIL expression was harmless to healthy livers. However, in virally infected livers, TRAIL expression induced apoptosis and steatosis whereas expression of FasL only resulted in apoptosis of hepatocytes without steatosis. After alcohol intake, TRAIL expression led to hepatic steatosis, without apoptosis of hepatocytes, indicating that TRAIL mediated apoptosis and steatosis may be independently modulated after viral infection and alcohol intake. In viral hepatitis and after alcohol intake, Ad-TRAIL mediated steatosis can be inhibited by injection of a neutralising TRAIL antibody. CONCLUSIONS: We identified TRAIL as a new mediator of hepatic steatosis in viral hepatitis and after alcohol intake. Consequently, TRAIL mediated hepatotoxicity has to be considered in patients with viral hepatitis and alcoholic liver disease.     

结肠癌中肿瘤坏死因子相关凋亡诱导配体受体的表达

背景：肿瘤坏死因子(17NF)相关凋亡诱导配体(TRAIL)是最近发现的TNF家族新成员，可诱导许多恶性肿瘤细胞凋亡。已知TRAIL是通过其受体起作用的，因此肿瘤对TRAIL受体的表达状况，决定了其对TRAIL的敏感性。目的：检测TRAIL受体(R1、R2、R3、R4)在结肠癌组织中的表达，为TRAIL应用于结肠癌的临床治疗提供理论基础。方法：取16例新鲜结肠癌组织提取mRNA，用逆转录聚合酶链反应(RT-PCR)方法检测TRAIL受体的表达。结果：12例结肠癌组织仅表达TRAIL-R1、R2，不表达R3、R4，而4例结肠癌组织除表达R1、R2外，还表达R3。结论：结肠癌组织表达TRAIL受体，多数仅表达R1、R2，但也有的除表达R1、R2外，还表达R2。TRAIL可能在结肠癌细胞凋亡中起重要作用。     

Tumor necrosis factor alpha production by peripheral blood mononuclear cells of patients with chronic liver disease

We investigated the production of tumor necrosis factor alpha by peripheral blood mononuclear cells of patients with chronic liver disease and its association with hepatitis activity. Tumor necrosis factor alpha production was measured with an enzyme-linked immunosorbent assay. Tumor necrosis factor alpha production by peripheral blood mononuclear cells stimulated with recombinant gamma-interferon of patients with chronic active hepatitis (5.8 +/- 4.0 units per ml, p less than 0.05) and patients with cirrhosis (4.1 +/- 2.1 units per ml, p less than 0.05) was significantly increased when compared with controls (2.5 +/- 1.6 units per ml). Tumor necrosis factor alpha production by peripheral blood mononuclear cells stimulated with a combination of recombinant gamma-interferon and recombinant interleukin 2 of patients with chronic persistent hepatitis (5.8 +/- 3.8 units per ml, p less than 0.05), patients with chronic active hepatitis (8.9 +/- 3.0 units per ml, p less than 0.001) and patients with cirrhosis (6.7 +/- 3.2 units per ml, p less than 0.05) was significantly increased in comparison with controls (3.3 +/- 1.8 units per ml). Tumor necrosis factor alpha production of patients with chronic active hepatitis was significantly higher than that of patients with chronic persistent hepatitis (p less than 0.05). There was a significant correlation (r = 0.5699, p less than 0.005) between tumor necrosis factor alpha production and histologic activity index in patients with chronic persistent hepatitis or chronic active hepatitis. These findings show that tumor necrosis factor alpha production is increased in chronic liver disease and that the increased tumor necrosis factor alpha production is related to hepatitis activity.     

Identification of tumor necrosis factor-alpha-related apoptosis-inducing ligand (TRAIL) and its receptors in adult rat ventral prostate

Tumor necrosis factor-alpha-related apoptosis-inducing ligand (TRAIL) is a member of the tumor necrosis factor-alpha (TNF-alpha) family of cytokines that is known to induce apoptosis upon binding to its death domain-containing receptors, DR4/TRAIL-R1 and DR5/TRAIL-R2. Two additional TRAIL receptors, DcR1/TRAIL-R3 and DcR2/TRAIL-R4, lack functional death domains and act as decoy receptors for TRAIL. In this study, the presence of TRAIL and its receptors was investigated in adult rat hormonosensitive ventral prostate. TRAIL and its receptors were identified in the rat ventral prostate in terms of protein and mRNA. TRAIL and its receptors were immunolocalized in prostatic epithelial cells.     

The involvement of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) in atherosclerosis

OBJECTIVES: Herein, we determined the significance of tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) in atherosclerotic vascular disease. BACKGROUND: Inflammation is associated with the pathogenesis of atherosclerosis. The TNF-related apoptosis-inducing ligand/APO-2L, a member of the TNF superfamily, has a role in apoptosis induction and is recognized for its immunomodulatory properties. METHODS: Stable and vulnerable atherosclerotic human plaques and aortas from atherosclerotic mice were assayed for the presence of TRAIL, and its inducibility was assayed by immunoblot and real-time polymerase chain reaction on peripheral mononuclear cells incubated with oxidized low-density lipoprotein (oxLDL). Enzyme-linked immunosorbent assay was used for the determination of soluble TRAIL levels in atherosclerotic patients. RESULTS: Tumor necrosis factor-related apoptosis-inducing ligand is present in stable atherosclerotic lesions, is increased in vulnerable plaques, and is found to colocalize with CD3 cells and oxLDL. The TNF-related apoptosis-inducing ligand messenger ribonucleic acid (mRNA) and protein expression was up-regulated in peripheral blood mononuclear cells after incubation with oxLDL. Serum levels of soluble TRAIL but not TNF-alpha or Fas-ligand were reduced significantly in patients with unstable angina as compared with patients with stable atherosclerotic disease and healthy subjects. A negative correlation was demonstrated between soluble TRAIL and C-reactive protein levels but not with levels of mRNA of TRAIL in peripheral blood mononuclear cells. CONCLUSIONS: Tumor necrosis factor-related apoptosis-inducing ligand is expressed in plaque-infiltrating CD3 cells and induced by oxLDL, whereas levels of soluble TRAIL are reduced in patients with acute coronary syndromes and negatively correlate with C-reactive protein levels. These results support a possible role for TRAIL in atherosclerosis.     

On the TRAIL to therapeutic intervention in liver disease

Hepatocellular carcinoma (HCC) ranks among the 10 most common cancers worldwide. The fact that HCC is resistant to conventional chemotherapy and is rarely amenable to radiotherapy leaves this disease with no effective therapeutic options and a very poor prognosis. Therefore, the development of more effective therapeutic tools and strategies is much needed. HCCs are phenotypically and genetically heterogeneous tumors that commonly emerge on a background of chronic liver diseases, most of which culminate in cirrhosis, such as alcoholic cirrhosis and chronic hepatitis B and C infections. This review outlines recent findings on the progression of liver disease, including our knowledge of the role of apoptotic processes, with an emphasis on the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). The proapoptotic and antiapoptotic properties of TRAIL, its involvement in liver injury, and its potential as a therapeutic agent in fibrosis and HCC are discussed. Several contradictory and confusing data have not yet been resolved or placed into perspective, such as the influence of factors that determine the TRAIL sensitivity of target cells, including the tumor microenvironment or cirrhotic tissue. Therefore, we assess these data from the perspectives of gastroenterologists (P.S. and M.W.B.) and a molecular oncologist (I.H.) with research interests in liver injury, apoptosis, and experimental therapeutics.     

外周血单个核细胞TRAIL mRNA和血清sTRAIL水平与HBV感染肝损伤的相关性

目的:探讨慢性乙型肝炎(CHB)患者外周血单个核细胞(PBMCs)肿瘤坏死因子相关凋亡诱导配体(TRAIL)mRNA及血清可溶性TRAIL(sTRAIL)水平与HBV感染肝损伤的关系.方法:采用TaqMan实时荧光定量RT-PCR(FQ- RT-PCR)检测58例慢性肝炎患者外周血PBMCs中TRAIL mRNA水平,采用夹心酶联免疫吸附法分析其血清sTRAIL水平,同时与血清HBV DNA滴度和肝功能相关指标,进行相关性分析.结果:除轻度慢性乙肝外,其他各型慢性乙型肝炎患者血清sTRAIL水平均显著低于健康对照组(t=2.91,P<0.05),各型慢性乙肝之间无显著性差异,与白蛋白(ALB)呈显著正相关(r =0.426,P<0.05),与TBIL、ALT及HBV DNA滴度无相关性.各型慢性乙肝患者PBMCs中TRAIL mRNA水平显著高于健康对照组(t= 28.31.P<0.001),与肝功能指标及血清HBV DNA滴度无相关性.结论:血清sTRAIL水平降低与肝损伤相关,提示单个核细胞膜结合型TRAIL增高与肝损害及乙肝病程迁延不愈有关.