类泛素蛋白FAT10在食管癌中的表达及生物学作用

目的:探讨类泛素蛋白FAT10的异常表达在食管癌（esophageal carcinoma,ECA）进展中的作用机制。方法:采用RT-PCR和Western blot法检测FAT10在30例ECA标本中的mRNA和蛋白表达水平。siRNA技术干扰食管癌细胞ECA-109中FAT10表达后,MTT检测细胞增殖,流式细胞术检测ECA-109细胞周期和细胞凋亡的变化,Western blot检测Akt/GSK3β信号通路的变化。结果:RT-PCR和Western blot结果显示,FAT10在食管癌组织中的表达水平较癌旁组织显著上调（P<0.05）。siRNA技术干扰ECA-109细胞中FAT10表达后,ECA-109细胞生长速度明显下降（P<0.05）。流式细胞术结果显示FAT10 siRNA干扰ECA-109细胞48h时,对细胞周期分布无明显影响（P>0.05）。但FAT10表达下调有促凋亡作用,与对照组相比,干扰组的细胞凋亡率显著升高,差异有统计学意义（P<0.05）。Western blot检测到ECA-109细胞中Akt和GSK3β的磷酸化水平都明显下降。结论:FAT10基因在食管癌组织中表达上调,下调FAT10的表达能够抑制食管癌进展,机制可能是通过诱导肿瘤细胞凋亡来实现的。     

Gankyrin分子结构及其功能研究进展

肝细胞癌是我国最常见的恶性肿瘤之一，与多种肿瘤相关基因的异常表达密切相关。Gankyrinc Gann ankyrin re peats，癌性锚蛋白重复序列，GeneBank NM-02814是近年来发现的第一个在肝细胞瘤中普遍激活的瘤基因，几乎高表达于所有的肝瘤组织，并通过依赖泛素的蛋白酶解系统介导多种细胞周期调控蛋白、转录因子以及抑癌蛋白如p53、p16（INK4A）的降解，研究表明，Gankyrin在肝癌的发生过程及肝细胞的生长周期调控中发挥重要作用，在肝细胞癌的病理诊断方面具有一定的应用前景，同时也可能成为肝细胞癌基因治疗的潜在靶点。     

泛素-蛋白酶体途径与恶性肿瘤关系的研究进展

细胞内蛋白质的产生和降解必须保持着动态平衡,才能维持细胞的稳态和正常功能。泛素-蛋白酶体途径(ubiquitin-proteasome pathway,UPP)是细胞内蛋白质选择性降解的重要途径,泛素分子主要通过泛素活化酶、泛素结合酶和泛素-蛋白连接酶与靶蛋白结合形成一条多泛素链,将底物蛋白泛素化,使靶蛋白被26S蛋白酶体所识别和降解。UPP可高效并高选择性地降解细胞内蛋白质,尤其是一些短寿命的细胞周期调节蛋白、癌基因和抑癌基因产物以及变性变构蛋白等。泛素化过程是真核细胞内重要的蛋白质质控系统,参与细胞的多种生理活动过程,比如细胞凋亡、MHCⅠ类抗原的递呈、细胞周期以及细胞内信号传导等,对维持细胞正常的生理功能具有十分重要的意义。当泛素-蛋白酶体系统对靶蛋白的降解功能失常时,可以引起癌蛋白聚集、抑癌蛋白异常降解、突变细胞凋亡受阻和增殖加速,从而导致肿瘤的发生。UPP的异常改变不仅与恶性肿瘤的病因学有着直接关素,并且与恶性肿瘤的发展和预后有着密切的关系。     

去泛素化酶-USP7通过影响相关癌蛋白参与肿瘤的发生与发展

蛋白质的泛素化程度决定着蛋白质的命运,细胞内存在两类针对蛋白质泛素化修饰的酶,一类是让某个特定蛋白泛素化增强的酶,另一类是让某个特定蛋白去泛素化的酶,这两类酶维持着正常细胞内80％ ～ 90％蛋白的新陈代谢.越来越多的证据支持这两类酶的异常与肿瘤的发生发展有较强的关联.其中USP7,一个去泛素化酶,有大量的文章报道显示它广泛参与影响肿瘤的进程.我们检索了近年来USP7与肿瘤关系的文献,系统回顾了它在肿瘤发生、发展中的作用与机制,并指出研究中存在的问题及将来的发展方向.     

UbcH10与肿瘤关系研究进展

泛素-蛋白酶体系统（UPS）是蛋白质选择性降解的最重要机制之一。蛋白质的泛素化是一个非常复杂而缜密的级联酶促反应过程,参与调节细胞内多种蛋白的表达水平和功能活性。泛素-蛋白酶体系统的异常与恶性肿瘤的发生和进展有着密切的关系。泛素偶联酶UbcH10属于泛素偶联酶E2家族,其与特定的E3酶相互作用引起底物蛋白的降解,是一种参与细胞有丝分裂调控的细胞周期蛋白。UbcH10可激活Cdc20/APC,与细胞周期进展、细胞分裂、染色体分离密切相关。UbcH10表达异常可导致细胞的染色体不稳定,细胞分裂异常。目前已有研究证明UbcH10是一种具有癌基因性质的泛素偶联酶。UbcH10在乳腺癌、结肠癌、胃癌、卵巢癌、肝癌、脑胶质瘤、淋巴瘤等多种肿瘤中高表达并且与肿瘤分期呈正相关,提示不良预后,可能成为新的肿瘤标志物或治疗靶点。本文就近年来关于UbcH10在肿瘤中作用的研究进展加以综述。      

肝细胞癌P53蛋白的表达及临床意义的研究

目的与方法：为了阐明Ｐ５３蛋白在人肝癌细胞中表达及临床意义,应用了免疫组织化学染色方法检测肝细胞癌Ｐ５３蛋白表达情况。结果：４９％的病例显示有Ｐ５３蛋白的表达,低分化癌的Ｐ５３蛋白表达率显著高于高、中分化癌。结论：这些资料显示：导致Ｐ５３蛋白异常表达的Ｐ５３基因突变是肝细胞癌的一种常见分子结构改变,是评价肝细胞癌预后有价值的一个生物学指标。     

类泛素蛋白与肝癌

类泛素蛋白是一类与泛素有类似空间结构及酶修饰系统的蛋白质,它们在调节蛋白质功能中发挥着重要作用。类泛素蛋白主要通过对底物蛋白进行类泛素化修饰而发挥核质转运、转录调节、稳定蛋白质、应激反应以及细胞周期调控等多种生物学功能。近年来有大量的研究表明类泛素蛋白功能失调与肝癌的发生、增殖、凋亡以及血管新生等过程密切相关;并且在抗肿瘤药物的研究中也发现,通过调控类泛素化修饰过程可以改变化疗药物的抗肿瘤作用,进而影响肝癌的化疗敏感性,这表明类泛素蛋白可能成为一个新的肿瘤防治靶点。探究类泛素蛋白在肝癌发生、发展中的作用机制对诊断和治疗肝癌有着重要作用。      

FAT10、NF-κB p50在乳腺浸润性导管癌中的表达及其临床意义

目的 探讨双泛素（FAT10）和核因子 κB p50（NF κB p50）在乳腺浸润性导管癌中的表达及其与临床病理特征的关系。方法 应用Max VisionTM免疫组织化学法,检测112例乳腺浸润性导管癌组织和53例癌旁组织中FAT10与NF-κB p50的表达,并分析两者表达的相关性及其与乳腺癌临床病理特征的关系。结果 FAT10和NF-κB p50在乳腺浸润性导管癌中的阳性表达率分别为77.68％（87／112）和81.25％（91／112）,明显高于癌旁组织的39.62％（21／53）和45.28％（24／53）,差异均有统计学意义（P＜0.001）。FAT10、NF-κB p50在乳腺浸润性导管癌中的表达与淋巴结转移、远处转移及TNM分期有关（P＜0.05）,而与患者的年龄、肿瘤大小及分子分型无关（P＞0.05）。FAT10与NF-κB p50在乳腺浸润性导管癌中的表达呈显著正相关（r=0.624,P＜0.001）。结论 FAT10、NF-κB p50的表达与乳腺浸润性导管癌的恶性程度及侵袭转移密切相关,两者可能共同促进肿瘤的发生发展。     

FAT10基因单体型与肝细胞癌的相关性研究

背景与目的:人类白细胞抗原FAT10是类泛素调节子蛋白家族中的一员,被认为与肝细胞癌(hepatocellular carcinoma,HCC)发生、发展密切相关。本研究探讨FAT10基因单体型与肝细胞癌的关系。方法:收集254例肝癌病例和268例健康对照人群外周血标本,提取DNA,通过DNA测序分析方法,检测两组人群FAT10基因外显子和侧翼序列单核苷酸多态性。应用Haploview统计软件分析研究对象的连锁不平衡和单体型,并应用病例对照分析方法进行相关性研究。结果:在肝癌组和对照组FAT10基因外显子和侧翼序列上共检测到10个多态性位点。遗传不平衡发现-143 A/G、-121 A/G、+3446 C/T、+3476 T/C、+3527 T/C、+3607 T/C、+3620 C/G、+3803 C/G、+3809 G/T 9个SNPs在同一个单体型块,其中-121 A/G、+3476 T/C、+3607 T/C、+3620 C/G和+3809 G/T多态位点完全连锁。进一步选择-143 A/G、+3476 T/C和+3527T/C 3个tagSNPs进行关联分析和单体型构建,发现-143 A/G和+3476 T/C基因型与相应的野生型纯合子相比能明显降低肝癌发病的风险(P<0.05)。进一步单体型分析发现ATT、ATC、GCT和ACT 4种单体型,其中肝癌患者的GCT和ACT单体型频率显著低于对照组(P<0.05),而ATT单体型频率显著高于对照组(P<0.05),经过1×108的随机置换检验校正后,ATT和GCT单体型与肝癌的发病风险仍然显著相关。结论:FAT10基因单体型可能与肝癌的发病风险相关,ATT单体型可能是肝癌的遗传标志。     

双泛素蛋白诱导自噬对肝癌细胞放射敏感度的影响

目的 探讨双泛素蛋白（FAT10）对肝癌细胞自噬水平的调节作用,并进一步明确FAT10诱导自噬对肝癌细胞放射敏感度的影响。方法 本实验首先通过Western blot及免疫组织化学方法分别从肝癌细胞及临床标本中验证FAT10对自噬相关蛋白的调控作用,进而通过克隆存活实验以明确FAT10诱导自噬对肝癌细胞放射敏感度的调节作用。结果 FAT10过表达可促进自噬相关蛋白Beclin1和LC3-Ⅰ/Ⅱ表达并抑制p62的表达,且经X射线照射后上述表达改变更明显。免疫组织化学分析结果显示FAT10与Beclin1具有显著相关性（P<0.01）,高表达FAT10的肝癌标本同时伴有Beclin1表达升高。克隆存活实验表明FAT10过表达增加肝癌细胞的放射抵抗性,敲除FAT10则增加肝癌细胞的放射敏感度。当使用自噬抑制剂3-MA或特异性干扰Beclin1以抑制肝癌细胞发生自噬后则上述FAT10表达改变不能引起肝癌细胞的放射敏感度的改变。结论 FAT10表达增加可通过诱导自噬形成进而增强肝癌细胞的放射抵抗性。     

Expression of the FAT10 gene is highly upregulated in hepatocellular carcinoma and other gastrointestinal and gynecological cancers

The ubiquitin-like modifier (UBL) family has recently generated much interest in the scientific community, as it is implicated to play important regulatory roles via novel protein-protein modification. FAT10 (diubiquitin) belongs to this family of proteins, comprising two ubiquitin-like moieties fused in tandem, and has been implicated to be involved in the maintenance of spindle integrity during mitosis. As FAT10 may play a role in the regulation of genomic stability, we examined if there is an association between FAT10 expression and hepatocellular carcinoma (HCC) or other cancers. Northern blot analyses revealed upregulation of FAT10 expression in the tumors of 90% of HCC patients. In situ hybridization as well as immunohistochemistry utilizing anti-FAT10 antibodies localized highest FAT10 expression in the nucleus of HCC hepatocytes rather than the surrounding immune and non-HCC cells. FAT10 expression was also found to be highly upregulated in other cancers of the gastrointestinal tract and female reproductive system. In conclusion, we demonstrated upregulation of FAT10 expression in various gastrointestinal and gynecological cancers. Its overexpression is unrelated to the general increase in protein synthesis or a general immune/inflammatory response to cancer. Rather, FAT10 may modulate tumorigenesis through its reported interaction with the MAD2 spindle-assembly checkpoint protein.     

FAT10 promotes hepatocellular carcinoma (HCC) carcinogenesis by mediating P53 degradation and acts as a prognostic indicator of HCC

BackgroundWith the advancement of hepatocellular carcinoma (HCC) treatment technology, the treatment options for HCC patients have increased. However, due to high heterogeneity, among other reasons, the five-year survival rate of patients is still very low. Currently, gene expression prognostic models can suggest more appropriate strategies for the treatment of HCC. This study investigates the role of FAT10 in hepatocarcinogenesis and its underlying mechanism.MethodsThe expression of FAT10 was detected by immunohistochemical method using tissue arrays containing 4 specimens of patients with digestive cancer. The expression of FAT10 was determined by a tissue microarray which included 286 pairs of HCC samples and corresponding normal mucosae and was further confirmed by real-time polymerase chain reaction (PCR) and western blot. The Kaplan-Meier survival curve was used to determine the correlation of FAT10 expression with patients’ recurrence and overall survival (OS) rate. In vivo, liver fibrosis, cirrhosis, and HCC models were established to assess the FAT10 expression. Moreover, FAT10 over-expressing cell lines were used to determine the molecular mechanism underlying the FAT10-induced cell proliferation and hepatocarcinogenesis by reporter gene measure, real-time PCR, and western blot. Based on TCGA database, signal pathways associated with FAT10 and HCC invasion and metastasis were analyzed by KEGG enrichment analyze.ResultsOverexpression of FAT10 in HCC was observed in this study compared with its expression in other digestive tumors. Clinicopathological analysis revealed that FAT10 expression levels were closely associated with tumor diameters and poor prognosis of HCC. This study also confirmed through in vivo experiments that the expression of FAT10 in liver fibrosis, cirrhosis, and HCC gradually increases. Further study revealed that forced FAT10 expression enhanced the growth ability of HCC cells and mediated the degradation of the critical anti-cancer protein p53, which led to carcinogenesis. Finally, 9 signal pathways related to HCC metastasis were obtained through bioinformatics analysis.ConclusionsFAT10 may act as a proto-oncogene that facilitates HCC carcinogenesis by mediating p53 degradation, and the expression of FAT10 is negatively correlated with the prognosis of HCC patients. FAT10 is expected to become a potential combined target and prognostic warning marker for HCC treatment.     

Increased FAT10 expression is related to poor prognosis in pancreatic ductal adenocarcinoma

It has been reported that FAT10 plays an important role in cell proliferation. Their activity is increased in malignant cells compared to benign cells. However, the clinical and functional significance of FAT10 expression has not been characterized previously in pancreatic ductal adenocarcinoma (PDAC). The purpose of this study was to assess FAT10 expression and to explore its contribution to PDAC. Real-time quantitative PCR was performed to examine FAT10 expression in 38 pairs of fresh frozen PDAC tissues and corresponding noncancerous tissues. Using immunohistochemistry, we performed a retrospective study of the FAT10 expression levels on 134 archival PDAC paraffin-embedded samples. The relationship between FAT10 mRNA expression and clinicopathological features was analyzed by appropriate statistics. Kaplan-Meier analysis and Cox proportional hazards regression models were used to investigate the correlation between FAT10 expression and prognosis of PDAC patients. The relative mRNA expression of FAT10 was significantly higher in PDAC tissues than in adjacent noncancerous tissues (P?<?0.001). By immunohistochemistry, the data revealed that high FAT10 expression was significantly correlated with clinical stage (P?<?0.001), histological differentiation (P?=?0.004), and lymph node metastasis (P?=?0.013). Consistent with these results, we found that high expression of FAT10 was significantly correlated with poor survival in PDAC patients (P?<?0.001). Furthermore, Cox regression analyses showed that FAT10 expression was an independent predictor of overall survival. In conclusion, this study confirmed the overexpression of FAT10 and its association with tumor progression in PDAC. It also provided the first evidence that FAT10 expression in PDAC was an independent prognostic factor of patients, which might be a potential diagnostic and therapeutic target of PDAC.     

FAT10通过激活RhoA介导肝细胞性肝癌侵袭转移*

目的:探讨FAT 10与肝细胞性肝癌（hepatocellularcarcinoma ,HCC ）恶性病理特征间的相关性,及FAT 10对细胞骨架蛋白F-actin的影响及可能的机制。方法:通过免疫组织化学技术检测108 例肝癌组织标本中FAT 10及active-RhoA蛋白表达,分析它们与患者临床病理特征之间的相关性及二者间的相关性;用7721、HepG2 肝癌细胞株瞬时转染质粒过表达FAT 10,用Huh 7 及LM3 细胞株转染siRNA 干扰FAT 10表达,利用Westernblot方法检测过表达和干扰FAT 10后肝癌细胞中active- 、total-RhoA 和ROCK 蛋白表达的变化;利用免疫荧光检测7721细胞过表达FAT 10后细胞骨架蛋白F-action 的变化。结果:免疫组织化学结果及临床数据的关联性分析表明:高表达FAT 10或active-RhoA均与肝癌转移和复发密切相关（FAT 10:复发P = 0.004,转移P = 0.031;active-RhoA:复发P = 0.026,转移P = 0.036）,且二者的表达水平之间呈明显正相关（P < 0.001）;生存分析的结果表明:高表达FAT 10或RhoA组患者预后明显差于各自低表达组（FAT 10:P = 0.026;active-RhoA:P = 0.019）。 Westernblot检测显示过表达FAT 10增加active-RhoA和ROCK 蛋白表达;反之,干扰FAT 10则抑制active-RhoA和ROCK 蛋白表达（均P < 0.01）。 免疫荧光显示肝癌细胞株7721过表达FAT 10可促进细胞骨架蛋白F-actin的表达和胞膜聚积及连续性变化。结论:FAT 10与肝癌恶性病理特征密切相关;并可能通过激活RhoA促进肝癌细胞骨架改变。      

Increased Expression of FAT10 is Correlated with Progression and Prognosis of Human Glioma

FAT10, as a small ubiquitin-like modifier, plays an important role in various cellular processes, including mitosis, immune response, and apoptosis, the dys-regulation of which may arise tumorigenesis. Therefore, the aim of this study was to examine the expression of FAT10 at gene and protein levels in glioma samples with different WHO grades and its association with survival. One hundred and twenty-eight glioma specimens and 10 non-neoplastic brain tissues were collected. Immunohistochemistry assay, quantitative real-time PCR and Western blot analysis were carried out to investigate the expression of FAT10. Kaplan-Meier method and Cox's proportional hazards model were used in survival analysis. Immunohistochemistry showed that FAT10 protein was over-expressed in glioma tissues. FAT10 mRNA and protein levels were both higher in glioma compared to control on real-time PCR and Western blot analysis (both P?相似文献   

TNF—α和IFN-γ诱导人乳头状甲状腺癌细胞FATIO过表达及染色体核型异常

目的：观察TNF-α和IFN-γ通过诱导人乳头状甲状腺癌TPC-1细胞中FAT10的表达而导致染色体核型异常。方法：采用电穿孔法将FAT10siRNA转染人TPC-1细胞,采用Westernblot检测各组细胞中FAT10蛋白的表达变化．用染色体核型分析TNF—d和IFN-γ诱导TPC-1细胞非整倍体现象。结果：West—ernblot结果显示,TPC-1细胞经TNF-α和IFN-γ诱导后,FAT10过表达。FAT10 siRNA干扰可以有效抑制TPC-1细胞中FAT10的表达,并且通过抑制FAT10表达,可以有效抑制TNF—α和IFN-γ诱导的非整倍体。进而发现FAT10表达具有拮抗TNF-α和IFN-γ诱导的TPC-1细胞凋亡的作用。结论：FAT10介导了TNF-α和IFN-γ诱导的TPC-1细胞的非整倍体现象,并具有拮抗凋亡的作用。