DNA甲基化导致肝细胞癌SYK基因失表达

目的：探讨SYK（Spleen tyrosine kinase，脾酪氨酸激酶）在肝细胞癌中的表达和不表达的机制。方法：分别用逆转录-聚合酶链反应（RT—PCR）方法和甲基化特异性聚合酶链反应（Methylation—specific PCR，MSP）检测SYK基因在肝癌细胞系（HepG2和Hep3B）和34例肝细胞癌组织、癌旁非瘤组织中的表达和甲基化情况。结果：肝癌细胞系Hep3B表达SYKmRNA，而HepG2不表达SYK mRNA、DNA甲基化转移酶抑制剂5-aza-2’-deoxyeytidine处理HepG2后，SYK重新表达．Hep3B细胞SYK甲基化阴性，HepG2细胞SYK甲基化阳性；34例肝细胞癌组织标本中，5例SYKmRNA表达阴性，SYK基因甲基化均阳性；29例SYK mRNA表达阳性，其中3例SYK甲基化阳性．其余26例SYK甲基化阴性。肿瘤组织SYK基因的甲基化率为23．5％（8／34），而瘤旁肝组织中为8．8％（3／34）。结论：SYK基因启动子甲基化导致肝细胞癌SYK mRNA失表达、可能是肝癌发病的机制之一。     

DNA甲基化在肝细胞癌中的研究进展

近来大量研究表明,DNA甲基化异常在肿瘤的发生发展中起着重要的作用。目前针对肝细胞癌（hepatocellular carcinoma,HCC）中DNA异常甲基化的研究逐渐由基础实验拓展到临床应用领域,其具体内容涉及HCC的早期诊断、病情监测和预后评估以及针对基因异常甲基化的治疗等。     

肝细胞癌ASC基因启动子区甲基化及其mRNA表达研究

  目的  分析Wnt途径拮抗剂Dickkopf-3(DKK3)蛋白在肝细胞癌中表达和亚细胞定位, 探讨其在肝细胞癌中的临床意义。  方法  采用细胞免疫荧光和免疫组织化学方法, 分析肝癌细胞系及43例肝细胞癌与相应癌旁组织中DKK3的蛋白表达, 并对其中31例中DKK3基因的甲基化状态进行检测。  结果  DKK3蛋白在肝细胞癌组织中的高表达率为67.4%(29/43), 显著高于相应癌旁组织中的41.8%(18/43)(P=0.017), 且细胞核内呈明显高表达; 肝细胞癌组织中DKK3基因甲基化发生率为90.3%(28/31), 显著高于相应的癌旁组织中的64.5%(20/31)(P=0.015), DKK3基因的甲基化状态与蛋白表达无明显相关性(P=0.844);DKK3低表达的肝细胞癌患者5年总生存率和无瘤生存率明显高于高表达者(P=0.049, P=0.001)。  结论  肝细胞癌中DKK3基因的甲基化状态可能与肝细胞癌中DKK3蛋白表达呈负相关; DKK3在癌组织中的高表达可能对肝细胞癌具有促进而非抑制性作用, 可以作为判断肝细胞癌预后的指标。     

肝细胞癌多基因甲基化异常及其临床意义

目的 探讨肝细胞癌中多基因甲基化异常的发生率,研究肝细胞癌中多基因甲基化异常的临床意义.方法 收集60例肝细胞癌及相应的癌旁组织、16例肝炎后肝硬化组织、5例慢性肝炎和5例正常肝组织,筛选消化道肿瘤中APC、RASSF1A、p16、GSTP1、MGMT、DAPK、SOCS-1和RIZ18个甲基化异常频率高的肿瘤抑制基因,应用甲基化特异件聚合酶链反应(MSP)检测8个肿瘤抑制基因在所有标本中的甲基化状态.比较不同基因甲基化与非甲基化肝细胞癌患者的临床病理特征和生存情况.结果 肝细胞癌组织中,RASSF1A、APC、GSTP1、p16、RIZ1和MGMT基因的甲基化率分别为95.0%、90.0%、73.3%、65.0%、61.6%和60.0%,均高于相应的癌旁组织(均P＜0.05);癌旁组织中,MGMT、GSTP1和RIZ1基因的甲基化率分别为41.6%、40.0%和25.0%,均高于肝硬化组织(均P＜0.05).p16基因甲基化的肝细胞癌患者的平均年龄大于非甲基化者;巨块性肝细胞癌中,MGMT基因甲基化者的比例高于非甲基化者;MGMT基基甲基化者的无瘤生存期短于非甲基化者.结论 不同基因在肝细胞癌、癌旁和肝硬化组织中的甲皋化率差异显示了肝细胞癌发生中渐进的表观遗传学改变;GSTP1、RIZ1和MGMT基因的甲基化异常具有肿瘤风险评估和早期诊断价值,而MGMT基因的甲基化异常同时具有预后评估价值.     

miR-21表达与肝细胞癌患者预后的相关性

肝细胞癌(hepatocellular carcinoma,HCC)是常见的恶性实体肿瘤之一,在肿瘤相关疾病死亡率中排第二[1].临床上急需一种能够准确预测HCC患者疾病复发、转移和预后的标志物以改善患者临床疗效.报道表明在多种人类肿瘤中miR-21表达增加能够促进肿瘤细胞增殖、转移和侵入[2],且部分研究证实miR-21可以作为某些肿瘤诊断和预后标志物[3-5],然而HCC患者的miR-21表达情况及其对疾病预后的影响尚不清楚.本研究旨在探讨miR-21对评估HCC患者疾病预后的价值.     

肝细胞癌中免疫相关基因的预后作用

目的 探讨肝细胞癌（HCC）患者免疫相关基因特征的潜在预后生物标志物。方法 从TCGA数据库下载原始肝细胞癌数据,执行单样本基因集富集分析计算每个样本的免疫活性。利用“GSVA”包和“hclust”包将HCC样本分成高和低免疫细胞浸润组。ESTIMATE算法对每个HCC样本中的肿瘤微环境进行评分。“limma”包和维恩图确定有效的免疫相关基因。单因素Cox、LASSO回归和多因素Cox回归分析探索关键基因。“rms”包建立列线图并绘制校准曲线。结果 与高免疫细胞浸润组相比,低免疫细胞浸润组中样本的肿瘤纯度更高,免疫评分、ESTIMATE评分和基质评分较低。高免疫细胞浸润组免疫成分更丰富,TIGIT、PD-L1、PD-1、LAG3、TIM-3、CTLA4和HLA家族的表达水平更高。多因素Cox回归分析显示4个免疫相关基因（S100A9、HMOX1、IL18RAP和FCER1G）被用来构建预后模型。与其他临床特征相比,该预后模型的风险评分被确认为独立的预后因素。结论  本研究确定了肝细胞癌免疫相关核心基因,可用于肝细胞癌的靶向治疗和免疫治疗。     

肝细胞癌中ChREBP基因CpG岛甲基化与mRNA表达的相关性

目的 检测肝细胞癌中ChREBP基因CpG岛甲基化水平及mRNA表达水平,并探讨两者的相关性。方法 收集肝细胞癌及癌旁冰冻组织90例,采用亚硫酸氢钠处理结合克隆测序检测ChREBP基因CpG岛内29个CpG位点的甲基化水平;采用荧光定量PCR检测其中31对新鲜冰冻组织中ChREBP基因mRNA表达水平,分析甲基化水平与mRNA表达之间的关系。结果 ChREBP基因的5、6、7、14号CpG位点甲基化水平在肝细胞癌中显著低于其配对的癌旁组织（P<0.05）。其余CpG位点及整体甲基化在肝细胞癌与癌旁组织中差异无统计学意义（均P>0.05）。15、18、20、23、26、29号CpG位点在≥50岁年龄组的甲基化水平均高于<50岁年龄组（均P<0.05）。肝细胞癌中ChREBP基因mRNA表达水平低于癌旁组织（P=0.003）,但与甲基化无显著相关性（P>0.05）。结论 肝细胞癌中ChREBP基因mRNA表达水平低于癌旁组织,但这一改变可能不是通过影响DNA的甲基化水平实现的。     

Tip30基因甲基化与肝细胞癌临床预后的关系

肿瘤细胞DNA甲基化紊乱常表现为癌基因去甲基化和抑癌基因高甲基化,即抑癌基因功能失活是通过表观遗传调控抑制,而不是通过基因缺失或突变。既往研究在肝细胞癌中p16、SOCS-1、TFPI-2、E—cadherin、RASSF1A和NORE1B等抑癌基因常常表现为高甲基化状态,这些基因的高甲基化状态与肝细胞癌的发生、发展关系密切。     

通过竞争性内源RNA调控网络筛查肝细胞癌预后相关分子

目的：通过构建肝细胞癌（hepatocellular carcinoma，HCC）的竞争性内源RNA(competing endogenous RNAs，ceRNA）调控网络，寻找与HCC发生发展及预后相关的分子。方法：从TCGA数据库下载HCC转录组数据，通过“Perl”语言处理转化得到mRNA、lncRNA和miRNA的表达谱矩阵。通过“Edge R”包提取3种RNA的差异表达基因（differential expression genes，DGEs），其阈值为|log FC|>2.0 且P<0.01。通过数据库比对得到差异lncRNA-差异miRNA、差异miRNA-差异mRNA关系对，导入至Cytoscape 软件构建ceRNA调控网络图。整理3 种DGEs相关的生存数据，通过“Survival”包及Kaplan-Meier Plotter 分析软件进行生存分析，绘制DGEs的生存曲线，分析获取预后相关基因。结果：成功构建HCC的lncRNA相关ceRNA调控网络，通过该网络分析DGEs 间的相互作用和调控关系，获取3 条lncRNA-miRNA-mRNA 调控关系对，其中1 条调控通路（CCDC26-hsa-mir-141-EPHA2）符合ceRNA 理论。预后分析显示，14 个mRNA高表达组患者生存率低于低表达组，可作为HCC不良预后的生物标志物；1 个lncRNA（TSPEAR-AS1）和2 个mRNA（CPEB3 和PROK2）低表达组患者生存率低于高表达组（P<0.05 或P<0.01），可能是HCC的保护性基因。结论：通过HCC lncRNA 相关的ceRNA调控网络筛查到高表达的14 个mRNA可能为HCC不良预后相关分子，低表达的1 个lncRNA和2 个mRNA可能为HCC良好预后相关分子，研究结果为HCC治疗和预后测评提供了参考依据。     

早期肝细胞癌患者血清VEGF表达水平与预后的相关性

目的 探讨早期肝细胞癌(HCC)患者血清血管内皮细胞生长因子(VEGF)表达水平与预后的相关性.方法 回顾性收集77例早期HCC患者临床资料,所有患者均接受实验室相关指标检测.依据患者预后情况,分为预后良好组与预后不良组,分析早期HCC患者血清VEGF水平表达与预后的相关性.结果 经Logistic回归分析结果显示,血...     

Increased fibrillarin expression is associated with tumor progression and an unfavorable prognosis in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the sixth most common cancer and third most common cause of cancer-associated mortality worldwide. Hepatectomy and liver transplantation are the main treatments for early HCC. Immunotherapy and targeted therapy for advanced HCC have become increasingly popular; however, their clinical benefits are limited. Thus, identification of novel therapeutic targets for advanced HCC remains essential. Fibrillarin (FBL) is an essential nucleolar protein that catalyzes the 2′-O-methylation of ribosomal RNAs. Recently, experimental data have suggested that FBL can influence breast-cancer progression. However, the association between FBL expression and HCC remains known. In the present study, the UALCAN database was used to assess FBL mRNA expression in HCC. Immunohistochemistry analysis was performed to detect FBL protein expression in 139 patients with HCC. In addition, bioinformatic analysis was performed using the UALCAN, the Database for Annotation, Visualization and Integrated Discovery, cBioportal and TargetScan databases. Data were analyzed using Kaplan-Meier curves and the log-rank test, and a Cox proportional hazards regression model. The results demonstrated that FBL expression was significantly higher in tumor tissues compared with para-tumor tissues. Furthermore, high FBL expression was significantly associated with tumor diameter and advanced TNM stage in HCC. High FBL expression also predicted a shorter overall survival time and disease-free survival time in patients with HCC. Bioinformatics analysis demonstrated that FBL may be regulated by methylation modification. In addition, analyses of functional annotations using the Gene Ontology database indicated that FBL-related genes were predominantly enriched in DNA repair and proliferation-related cell-signaling pathways. Notably, high FBL expression signified larger tumor diameter, advanced tumor stage and a poor prognosis. Taken together, the results of the present study suggest that FBL may be a potential target for HCC treatment.     

Distinct DNA methylation patterns in cirrhotic liver and hepatocellular carcinoma

Abberrant DNA methylation is one of the hallmarks of cancerogenesis. Our study aims to delineate differential DNA methylation in cirrhosis and hepatic cancerogenesis. Patterns of methylation of 27,578 individual CpG loci in 12 hepatocellular carcinomas (HCCs), 15 cirrhotic controls and 12 normal liver samples were investigated using an array-based technology. A supervised principal component analysis (PCA) revealed 167 hypomethylated loci and 100 hypermethylated loci in cirrhosis and HCC as compared to normal controls. Thus, these loci show a "cirrhotic" methylation pattern that is maintained in HCC. In pairwise supervised PCAs between normal liver, cirrhosis and HCC, eight loci were significantly changed in all analyses differentiating the three groups (p < 0.0001). Of these, five loci showed highest methylation levels in HCC and lowest in control tissue (LOC55908, CELSR1, CRMP1, GNRH2, ALOX12 and ANGPTL7), whereas two loci showed the opposite direction of change (SPRR3 and TNFSF15). Genes hypermethylated between normal liver to cirrhosis, which maintain this methylation pattern during the development of HCC, are depleted for CpG islands, high CpG content promoters and polycomb repressive complex 2 (PRC2) targets in embryonic stem cells. In contrast, genes selectively hypermethylated in HCC as compared to nonmalignant samples showed an enrichment of CpG islands, high CpG content promoters and PRC2 target genes (p < 0.0001). Cirrhosis and HCC show distinct patterns of differential methylation with regards to promoter structure, PRC2 targets and CpG islands.     

Dll4分子在肝细胞癌中的表达及其与预后的关系

目的:探讨Dll4分子在肝癌组织中的表达及其在肝癌术后患者预后中的作用。方法:采用免疫组化方法检测28例肝癌组织以及癌旁组织中Dll4的表达水平。并结合患者随访情况分析Dll4蛋白表达水平与肝细胞癌术后患者预后的关系。结果:免疫组化结果显示Dll4蛋白表达主要定位于细胞浆,肝癌组织中Dll4蛋白表达明显高于癌旁组织（P＜0.05）。Cox模型多因素分析结果显示肝癌合并微血管侵犯与Dll4蛋白表达情况是患者预后的独立危险因素。结论:Dll4分子高表达的肝癌术后患者相对于低表达患者预后更差,术后生存时间更短。可能成为肝细胞癌新的预后标志物。     

基于TCGA数据库分析肝细胞肝癌组织中HMMR表达与患者临床特征及预后的相关性

目的:研究透明质酸介导的运动受体(hyaluronan-mediated motility receptor,HMMR)的表达与肝细胞肝癌(hepatocellular carcinoma,HCC)的发生发展以及预后的关系.方法:在本研究中,我们通过从癌症基因组图谱(the cancer genome atlas,TC...     

Elevated expression of Cripto-1 correlates with poor prognosis in hepatocellular carcinoma

Cripto-1 could promote tumorigenesis in a wide range of carcinomas, yet little is known in hepatocellular carcinoma (HCC). The expression of Cripto-1 and MMP-9 were assessed by immunohistochemistry in 205 HCC specimens. The correlation between Cripto-1 and MMP-9, clinicopathological/prognostic value in HCC was examined. Cripto-1 overexpression was correlated with larger tumor, TNM stage, BCLC stage and tumor recurrence. In multivariate analyses, Cripto-1 was an independent predictor for overall survival (OS) and time to recurrence (TTR). Cripto-1 expression was increased in TNM and BCLC stage-dependent manner. Cripto-1 overexpression was associated with poor prognosis in patients subgroups stratified by tumor size, tumor differentiation, TNM and BCLC stage. In addition, Cripto-1 was positively correlated with MMP-9 among 205 HCC samples. Patients with Cripto-1 upregulation had poor OS and shorter TTR in low and high aggressiveness groups. Furthermore, Cripto-1 had predictive validity for early and late recurrence in HCC patients. Combination of Cripto-1 and serum AFP was correlated with OS and TTR. In conclusion, Cripto-1 overexpression contributes to aggressiveness and poor prognosis of HCC. Cripto-1/AFP expression could be a potential prognostic biomarker for survival in HCC patients.     

Decreased expression of BATF2 is associated with a poor prognosis in hepatocellular carcinoma

Human BATF2, a basic leucine zipper protein, was recently detected in several normal immortalized cell lines but not in transformed cell lines. In addition, the expression of BATF2 also slowed the growth rate of malignant tumor cells injected into athymic nude mice. In this study, to study the role of BATF2 in hepatocellular carcinoma (HCC), we examined BATF2 expression in 50 paired HCC tumorous and nontumorous tissues, as well as in five HCC cell lines. Moreover, BATF2 expression in 114 HCC patients was evaluated using immunohistochemistry, and its relationship with clinicopathological parameters and prognosis was investigated. We found that BATF2 expression was significantly reduced in most HCC tumorous tissues, when compared with nontumorous tissues, as well as in the five HCC cell lines. Consistent with these results, the immunohistochemistry revealed that decreased BATF2 expression was present in 63 of the 114 cases and was significantly correlated with age (p = 0.006), tumor size (p = 0.046) and tumor differentiation (p = 0.030). Patients with negative BATF2 expression showed a shorter survival than those with positive expression (p = 0.016). Multivariate analysis revealed that BATF2 expression was an independent predictor of overall survival (p = 0.015). All the data support the hypothesis that BATF2 plays an important role in the progression of HCC and that it may work as a candidate tumor suppressor and a prognostic marker as well as a potential target for treatment.