肝细胞癌组织中PTEN蛋白表达

探讨抑癌基因PTEN在肝细胞癌 (HCC)组织及癌旁组织的表达、临床意义。采用免疫组织化学SP法检测PTEN。 4例正常肝组织均呈PTEN蛋白阳性 ;HCC及其癌旁肝组织中的阳性率分别为 5 8 8%(2 0 / 34)和 10 0 %(34/ 34) ,两者比较差异有显著性 (P <0 0 5 )。中分化癌阳性率为 77 8%(14 / 18) ,低分化阳性率为 2 5 %(3/ 12 ) ,两者比较差异有显著性 (P <0 0 0 1)。PTEN蛋白表达与年龄、性别、肿瘤大小、有无包膜及门脉癌栓均无明显关系 (P >0 0 5 ) ,但与HCC分化程度明显相关 ,HCC分化愈差 ,PTEN蛋白表达愈弱。PTEN蛋白表达与HCC分化程度明显相关。     

抑癌基因PTEN在原发性肝癌中的表达及意义

目的 研究抑癌基因PTEN在原发性肝癌发生过程中的作用及意义。方法 应用免疫组织化学和northern杂交分析60例原发性肝癌及对应癌旁组织中PTEN mRNA及PTEN蛋白表达情况,结合患者的临床病理资料分析PTEN在原发性肝肝癌中的意义。结果 PTEN蛋白明确定位于肝细胞胞浆内。60例HCC的癌组织中,PTEN蛋白阳性率为48.3％(29/60),明显低于癌旁肝组织的阳性率(100％)。PTEN蛋白在肝癌组织内的表达阳性率与肝癌的病理学分级、有无癌栓有关,PTEN蛋白在肝癌组织的Ⅰ～Ⅱ级、Ⅲ级、Ⅳ级的阳性率分别为84.0％、23.8％、21.4％,无癌栓形成组PTEN蛋白表达的阳性率为55.56%,有癌栓形成组PTEN蛋白表达的阳性率为26.7％。Northern杂交显示,PIEN基因在肝癌细胞内存在四个转录子,其大小分别为5.5、4.4、2.4、1.8 kb。患者肝癌组织内PTEN mRNA的表达水平明显低于对应的癌旁肝组织。PTEN 5.5 kb和4.4 kb的转录子表达水平的降低与血清中AFP水平、有无癌栓、有无卫星灶及病理学分级有关;2.4 kb的转录子表达水平降低与患者有无癌栓、有无卫星灶有关;1.8 kb转录子表达水平的降低与临床病理学指标无关。结论 PTEN在肝癌的发生过程中可能起重要作用,其表达水平有可能作为反映肝癌进展和预后的病理学指标。     

MicroRNA-21 regulates expression of the PTEN tumor suppressor gene in human hepatocellular cancer

BACKGROUND AND AIMS: microRNAs (miRNAs) are short noncoding RNAs that regulate gene expression negatively. Although a role for aberrant miRNA expression in cancer has been postulated, the pathophysiologic role and relevance of aberrantly expressed miRNA to tumor biology has not been established. METHODS: We evaluated the expression of miRNA in human hepatocellular cancer (HCC) by expression profiling, and defined a target gene and biologically functional effect of an up-regulated miRNA. RESULTS: miR-21 was noted to be highly overexpressed in HCC tumors and cell lines in expression profiling studies using a miRNA microarray. Inhibition of miR-21 in cultured HCC cells increased expression of the phosphatase and tensin homolog (PTEN) tumor suppressor, and decreased tumor cell proliferation, migration, and invasion. In contrast-enhanced miR-21 expression by transfection with precursor miR-21 increased tumor cell proliferation, migration, and invasion. Moreover, an increase in cell migration was observed in normal human hepatocytes transfected with precursor miR-21. PTEN was shown to be a direct target of miR-21, and to contribute to miR-21 effects on cell invasion. Modulation of miR-21 altered focal adhesion kinase phosphorylation and expression of matrix metalloproteases 2 and 9, both downstream mediators of PTEN involved in cell migration and invasion. CONCLUSIONS: Aberrant expression of miR-21 can contribute to HCC growth and spread by modulating PTEN expression and PTEN-dependent pathways involved in mediating phenotypic characteristics of cancer cells such as cell growth, migration, and invasion.     

抑癌基因PTEN及p53在肝细胞肝癌中表达的免疫组化研究

为探讨肝细胞肝癌组织中抑癌基因PTEN及p53蛋白的表达情况及临床病理意义。应用免疫组织化学技术检测了41例肝细胞肝癌及其相应的癌旁组织中PTEN和p53蛋白的表达情况。41例癌旁组织PTEN全部阳性表达,肝细胞肝癌组织中PTEN阳性表达率39％,阳性信号显示于胞浆中。p53阳性表达率51％,PTEN蛋白在肝细胞肝癌组织中的阳性表达与组织分化程度明显相关,高分化癌的阳性率为73％,低分化癌阳性率27％。肝细胞肝癌细胞中存在较高比例的PTEN蛋白阴性表达,说明在肝细胞肝癌的发生发展中PTEN基因失活起着重要作用,它的阳性表达可能有一定的预后意义。     

DJ-1基因在肝细胞癌中的表达及其与肝癌侵袭和转移的关系

目的 探讨DJ-1基因mRNA及其蛋白在肝细胞癌中的表达规律及其与肝细胞癌侵袭和转移的关系. 方法应用逆转录聚合酶链反应和免疫组织化学方法检测46例肝细胞癌中DJ-1基因mRNA及蛋白的表达情况,结合患者的临床病理资料分析DJ-1基因与肝细胞癌的侵袭与转移的关系.应用χ2检验进行统计学处理.结果 肝癌组织中DJ-1基因mRNA及蛋白的表达阳性率分别为69.6%(32/46)和58.7%(27/46),明显高于癌旁肝组织的表达阳性率[分别为39.1%(18/46)和34.8%(16/46)],χ2=8.587,P<0.05;且DJ-1基因蛋白在肝癌组织中的高表达与患者肿瘤的大小、甲胎蛋白水平、HBsAg、肿瘤的分化程度以及有无肝硬化无关(P>0.05),而与肿瘤有无包膜及有无门静脉癌栓有关(χ2=7.846,P<0.05).结论 DJ-1基因在肝细胞癌的侵袭和转移过程中可能起重要作用.     

Loss of heterozygosity suggests tumor suppressor gene responsible for primary hepatocellular carcinoma.

Primary hepatocellular carcinoma (PHC), epidemiologically associated with chronic hepatitis B virus (HBV) infection, has historically been felt to be caused by the activation or introduction of an oncogene. However, transforming sequences from human PHC have not been reproducibly isolated. In this paper, evidence is presented that suggests PHC may result instead from the loss of an anti-oncogene. Seven of 12 human primary liver tumors tested against a panel of restriction fragment length polymorphisms (RFLPs) demonstrated loss of constitutional heterozygosity for markers on chromosome 4. Tumor and nontumor liver tissue were typed for 11 chromosome 4 RFLPs. In addition, at least one RFLP on nine other chromosomes (1, 2, 6, 7, 9, 11, 13, 14, and 17) was tested for allelic loss. Seven of nine tumors constitutionally heterozygous for chromosome 4q markers showed allele loss in tumor tissue. Six of the seven samples were jointly informative for both 4p and 4q markers. Five of the six demonstrated loss for only 4q RFLPs. In one individual, in which two samples were taken from distant locations within the same tumor, both samples showed loss of the same alleles. Among the other chromosomes informative for allele loss, one tumor showed changes on 13q. No other changes were observed in RFLPs located on the eight other chromosomes tested. These results indicate that an anti-oncogene may be located on 4q and suggest a mechanism for PHC and other cancers seroepidemiologically related to virus infection. Liver cancer caused by chronic HBV infection or other environmental agents may be linked through genetic events responsible for the loss of a tumor suppressor locus (anti-oncogene) located on chromosome 4.     

原发性肝癌MRI特征

目的探讨原发性肝癌的ＭＲＩ特征，以提高诊断准确性．方法原发性肝癌２９例，全部为男性，年龄３３岁～８０岁，平均５６岁．ＧｄＤＴＰＡ增强扫描１０例共１１个肿块．扫描序列为自旋回波（ＳＥ）、ＦＬＡＳＨ，扫描层厚８ｍｍ～１０ｍｍ．结果肿瘤不规则６９２％（３６／５２），边缘模糊３８５％（２０／５２），长ＴＥ肿瘤的信号强度增高不明显．假包膜征１９例，Ｔ１ＷＩ表现为低信号单环，Ｔ２ＷＩ为低信号或高信号单环，典型表现为外高内低双环．１５例镶嵌征Ｔ１ＷＩ和Ｔ２ＷＩ表现为肿瘤内线样或不规则低信号区．１３例斑征Ｔ２ＷＩ表现为肿瘤内高信号斑块．动态增强扫描肿瘤中心不规则强化３６４％，肿瘤边缘结节样强化４５５％．门静脉或下腔静脉瘤栓是原发性肝癌的辅助征象．结论原发性肝癌ＭＲＩ具有特征性．     

肝癌抑制基因-1肿瘤靶向性表及其特异性抗肿瘤作用

目的 建立肝癌抑制基因-1(HCCS1)肿瘤靶向性表达载体,提高肿瘤治疗的安全性.方法 活细胞计数试剂盒测定HCCS1高表达对正常细胞和肿瘤细胞的影响,荧光素酶试验检测肿瘤特异性启动子PEG-3p在正常肝细胞和肝癌细胞中的相对转录活性,AdEasyTM系统包装并利用PCR鉴定重组腺病毒Ad-PEG-3p-HCCS1,Western blot检测重组腺病毒感染后HCCS1在正常细胞和肿瘤细胞中的表达情况,结晶紫试验和四甲基偶氮唑盐试验观察该重组腺病毒体外抗肿瘤的靶向性. 结果 HCCS1高表达对肿瘤细胞株BEL-7404和SW-620的生长抑制作用明显超过正常细胞株L02和正常人肺成纤维细胞,96 h抑制率达60%.荧光素酶试验显示,PEG-3p在BEL-7404、BEL-7405、QGY-7703中的相对转录活性分别为L02的3.9、4.7、1.5倍.成功构建了新抑癌基因HCCS1肿瘤靶向性表达的重组腺病毒Ad-PEG-3p-HCCS1,Western blot检测结果显示,在BEL7404和QGY-7703中,HCCS1表达高于在L02中的表达.结晶紫试验和四甲基偶氮唑盐试验显示,Ad-PEG-3p-HCCS1与Ad-CMV-HCCS1相比,在不降低对肿瘤抑制效果的前提下,明显降低了对正常细胞的杀伤作用. 结论 肿瘤细胞对HCCS1的生长抑制作用更为敏感,PEG-3p在肝癌细胞中也具有肿瘤特异性,Ad-PEG-3p-HCCS1可特异性地在肿瘤细胞中表达HCCS1,从而提高HCCS1基因治疗的安全性.     

Mutation analysis of novel human liver-related putative tumor suppressor gene in hepatocellular carcinoma

AIM: To find the point mutations meaningful for inactivation of liver-related putative tumor suppressor gene (LPTS) gene, a human novel liver-related putative tumor suppressor gene and telomerase inhibitor in hepatocellular carcinoma. METHODS: The entire coding sequence of LPTS gene was examined for mutations by single strand conformation polymorphism (SSCP) assay and PCR products direct sequencing in 56 liver cancer cell lines, 7 ovarian cancer and 7 head neck tumor cell lines and 70 pairs of HCC tissues samples. The cDNA fragment coding for the most frequent mutant protein was subcloned into GST fusion expression vector. The product was expressed in E.coli and purified by glutathione-agarose column. Telomeric repeat amplification protocol (TRAP) assays were performed to study the effect of point mutation to telomerase inhibitory activity. RESULTS: SSCP gels showed the abnormal shifting bands and DNA sequencing found that there were 5 different mutations and/or polymorphisms in 12 tumor cell lines located at exon2, exon5 and exon7. The main alterations were A(778)A/G and A(880)T in exon7. The change in site of 778 could not be found in HCC tissue samples, while the mutation in position 880 was seen in 7 (10 %) cases. The mutation in the site of 880 had no effect on telomerase inhibitory activity. CONCLUSION: Alterations identified in this study are polymorphisms of LPTS gene. LPTS mutations occur in HCC but are infrequent and of little effect on the telomerase inhibitory function of the protein. Epigenetics, such as methylation, acetylation, may play the key role in inactivation of LPTS.     

Poor prognosis in carcinoma is associated with a gene expression signature of aberrant PTEN tumor suppressor pathway activity

Pathway-specific therapy is the future of cancer management. The oncogenic phosphatidylinositol 3-kinase (PI3K) pathway is frequently activated in solid tumors; however, currently, no reliable test for PI3K pathway activation exists for human tumors. Taking advantage of the observation that loss of PTEN, the negative regulator of PI3K, results in robust activation of this pathway, we developed and validated a microarray gene expression signature for immunohistochemistry (IHC)-detectable PTEN loss in breast cancer (BC). The most significant signature gene was PTEN itself, indicating that PTEN mRNA levels are the primary determinant of PTEN protein levels in BC. Some PTEN IHC-positive BCs exhibited the signature of PTEN loss, which was associated to moderately reduced PTEN mRNA levels cooperating with specific types of PIK3CA mutations and/or amplification of HER2. This demonstrates that the signature is more sensitive than PTEN IHC for identifying tumors with pathway activation. In independent data sets of breast, prostate, and bladder carcinoma, prediction of pathway activity by the signature correlated significantly to poor patient outcome. Stathmin, encoded by the signature gene STMN1, was an accurate IHC marker of the signature and had prognostic significance in BC. Stathmin was also pathway-pharmacodynamic in vitro and in vivo. Thus, the signature or its components such as stathmin may be clinically useful tests for stratification of patients for anti-PI3K pathway therapy and monitoring therapeutic efficacy. This study indicates that aberrant PI3K pathway signaling is strongly associated with metastasis and poor survival across carcinoma types, highlighting the enormous potential impact on patient survival that pathway inhibition could achieve.     

A phosphorylation-dependent intramolecular interaction regulates the membrane association and activity of the tumor suppressor PTEN

The PI 3-phosphatase PTEN (phosphatase and tensin homologue deleted on chromosome 10), one of the most important tumor suppressors, must associate with the plasma membrane to maintain appropriate steady-state levels of phosphatidylinositol 3,4,5-triphosphate. Yet the mechanism of membrane binding has received little attention and the key determinants that regulate localization, a phosphatidylinositol 4,5-bisphosphate (PIP₂) binding motif and a cluster of phosphorylated C-terminal residues, were not included in the crystal structure. We report that membrane binding requires PIP₂ and show that phosphorylation regulates an intramolecular interaction. A truncated version of the enzyme, PTEN_1–351, bound strongly to the membrane, an effect that was reversed by co-expression of the remainder of the molecule, PTEN_352–403. The separate fragments associated in vitro, an interaction dependent on phosphorylation of the C-terminal cluster, a portion of the PIP₂ binding motif, integrity of the phosphatase domain, and the CBR3 loop. Our investigation provides direct evidence for a model in which PTEN switches between open and closed states and phosphorylation favors the closed conformation, thereby regulating localization and function. Small molecules targeting these interactions could potentially serve as therapeutic agents in antagonizing Ras or PI3K-driven tumors. The study also stresses the importance of determining the structure of the native enzyme.     

Design of a retroviral-mediated ecdysone-inducible system and its application to the expression profiling of the PTEN tumor suppressor

We have engineered the ecdysone-inducible mammalian expression system for general retroviral delivery to cultured mammalian cells. We inducibly expressed PTEN in the glioblastoma cell line, U87MG, lacking this gene. Because nearly all cells are recruited on induction, we find both up- and down-regulated genes by cDNA microarray analysis. The changes we see are similar to those observed after treatment with LY294002, an inhibitor of phosphatidylinositol 3-OH kinase, fully consistent with the model that PTEN antagonizes phosphatidylinositol 3-OH kinase. Both treatments result in suppressed expression of the transforming growth factor (TGF)-beta gene and the genes of the cholesterol biosynthesis pathway. Our results illustrate the power of using a fully inducible expression system in conjunction with cDNA microarray analysis for exploring gene function.     

晚期糖基化终产物受体在肝细胞癌患者中的表达

目的 研究晚期糖基化终产物受体(RAGE)在原发性肝细胞癌(PHC)中的表达.方法 收集10例PHC患者的肝癌组织、癌旁组织、血清及正常人的血清;用RT-PCR及Western blot分别检测组织中RAGE基因及蛋白的表达;用ELISA检测血清RAGE表达,同时用化学发光法检测血清中甲胎蛋白(AFP)表达.结果 RA...     

上皮细胞粘附分子在肝动脉化疗栓塞治疗肝癌中的表达改变及其功能

目的明确肝动脉化疗栓塞(transcatheter hepatic arterial chemoembolization,TACE)治疗对肝细胞癌(hepatocellular carcinoma,HCC)肿瘤组织中肿瘤干细胞指示分子——上皮细胞粘附分子(epithelial cell adhesion molecule,Ep CAM)表达及肝癌干细胞生物学行为的影响。方法用实时PCR分别检测30例经TACE治疗和30例未经TACE治疗的HCC患者肿瘤组织中Ep CAM的表达水平。在此基础上,用Ep CAM的si RNA载体,在HCC细胞系Hep G2和高侵袭性的MHCC-97H中检测Ep CAM对抗肿瘤药物作用的影响;在MHCC-97H细胞系中,检测降低Ep CAM表达对MHCC-97H侵袭作用的影响。结果接受TACE治疗的HCC患者肿瘤组织中的Ep CAM表达水平升高(P0.05)。与对照组相比,在Hep G2细胞中转染Ep CAM的si RNA能够显著上调Hep G2细胞对分子靶向抗肿瘤药物索拉非尼以及细胞毒性化疗药物奥沙利铂和表柔比星的敏感性。在MHCC-97H中转染Ep CAM的si RNA能够显著抑制其侵袭作用。结论 TACE治疗可引起HCC组织中Ep CAM的表达水平明显升高;降低HCC细胞中Ep CAM表达水平,可导致HCC细胞的肿瘤干细胞特征如侵袭性显著下降,对抗肿瘤药物的敏感性升高。     

肝细胞癌患者血清癌基因和抑癌基因蛋白水平变化

目的 探讨肝细胞癌(HCC)患者血清常见的癌基因和抑癌基因水平变化.方法 2017年7月～2020年7月我院收治的慢性乙型肝炎患者40例,代偿期乙型肝炎肝硬化患者25例,失代偿期乙型肝炎肝硬化患者31例,HCC患者50例和同期体检的健康人40例,采用ELISA法检测血清癌基因转化基因(N-ras)、增殖相关基因(C-m...     

Transglutaminase 3 expression in hepatocellular carcinoma patients: Correlation with tumor features and survival profile

BackgroundTransglutaminase 3 (TGM3) regulates multiple oncogene pathways (GSK-3β/β-catenin pathway, Akt/ERK pathway, etc.) to promote hepatocellular carcinoma (HCC) cell proliferation, migration and invasion, however, its clinical value for HCC management is still limited. Therefore, we conducted this study to compare the TGM3 expression between tumor tissue and paired adjacent noncancerous tissue, aiming to explore the clinical application of TGM3 in HCC patients.MethodsTotally, 208 HCC patients were enrolled and their clinicopathological features were collected. Then, 208 pairs of HCC specimens and adjacent noncancerous specimens were used to detect TGM3 protein expression by IHC assay and assessed by a semi-quantitative scoring method. Besides, 157 pairs were proposed to detect TGM3 mRNA expression by RT-qPCR.ResultsBoth TGM3 protein (P<0.001) and mRNA (P<0.001) levels were increased in HCC specimens compared to adjacent noncancerous specimens. Besides, TGM3 high protein expression correlated with multifocal tumor nodules (P<0.001), advanced Barcelona Clinic Liver Cancer (BCLC) stage (P = 0.006), higher carcinoembryonic antigen (P = 0.038) and alpha-fetoprotein (AFP) (P<0.001). While TGM3 high mRNA expression correlated with multifocal tumor nodules (P = 0.025), largest tumor size ≥ 5.0 cm (P = 0.042) and higher AFP (P = 0.019). Furthermore, both TGM3 protein (P = 0.002) and mRNA (P = 0.028) high expressions correlated with shorter overall survival (OS). While after adjustment by multivariant Cox's regression, TGM3 protein high expression (vs. low) independently predicted worse OS (P = 0.004).ConclusionsTMG3 expression is increased in tumor tissue, also its high expression correlates with multiple tumor nodules, higher BCLC stage, abnormal AFP and reduced OS in HCC patients.     

Significance of cyclooxygenase—2 expression in human primary hepatocellular carcinoma

AIM：To clarife the significance of cyclooxygenase-2(COX-2)expression in human primary hepatcellular carcinoma(HCC)and adjacent nontumorous tissues.METHODS;TheCOX-2protein and mRNA were investigated in 27HCC tissues with adjacent nontumorous tissues,and 5histologically normal liver tissues,using immunohistochemistry and in situ hybridization.RESULTS:The well-differentiated HCC expressed COX-2protein(5.68&#177;1.19)more strongly than moderated HCC(3.43&#177;1.98)and poor differentiated HCC(3.33&#177;1.50)(P&lt;0.05 respectively),adjacent nontumorous tissues(4.93&#177;1.05)and normal live tissues(3.20&#177;1.92)(P&lt;0.01 respectively);More intensive staining of COX-2in adjacent nontumorous tissues was observed than that in normal liver tissues(P&lt;0.05).There was no significant difference among adjacent nontumorous tissues,moderately differentiated HCC and poorly differentiated HCC(P&gt;0.05).The expression of COX-2mRNA was observed in the cytoplasm of the cells of HCC and of gtthe hepatocytes in adjacent nontumorous tissues in which COX-2 protein was positive.CONCLUSION:The overexpression of COX-2 in well-differentiated HCsuggets that COX-2 may play a role in the early stages of hepatocarcinogensis.     

人肝癌组织特异性GGTmRNA亚型表达的研究

目的　探讨γ-谷氨酰转移酶 ( GGT) m RNA亚型转化与肝癌发生的关系。方法　采用 RT-PCR方法检测正常肝组织、良性肝病肝组织、肝癌组织、癌旁组织、远癌组织及肝转移癌癌周组织中三种 GGTm RNA亚型 ( F、H、P亚型 )的表达情况。结果　正常肝组织主要的 GGTm RNA类型为 F亚型 ,良性肝病及肝转移癌癌周组织亦以 F亚型为主 ;肝癌组织、癌旁组织及远癌组织 H亚型的阳性率显著高于正常肝脏及良性肝病肝组织 ( P<0 .0 5) ;肝癌组织 F亚型阳性率明显低于正常及良性肝病肝组织 ( P<0 .0 5)。结论　 GGTm RNA亚型转化与肝癌发生有密切关系 ;GGT基因检测为判断肝细胞癌变的灵敏方法     

原发性肝癌合并肝源性糖尿病的治疗方法及预后相关因素分析

目的探讨原发性肝癌合并肝源性糖尿病（PHCHD）的治疗方法,并分析其预后影响因素。方法 68例PHCHD患者均行手术切除治疗,其中肝大部切除19例,半肝切除13例,次半肝切除36例;术后单纯皮下注射胰岛素46例,胰岛素皮下注射加阿卡波糖口服22例。采用Kaplan-Meier法分析患者的临床资料与生存时间的关系,采用COX多因素回归分析PHCHD预后相关因素。结果本组中位生存期32个月,1、3、5 a生存率为76.13%、47.36%、36.12%。血清HCVAb、Child-Pugh分级、TNM分期、肝硬化、门脉瘤栓、血管侵犯与患者生存时间有关（P均〈0.05）;肝硬化、血管侵犯、门脉瘤栓与患者的预后有关（P均〈0.05）。结论手术切除和胰岛素皮下注射是治疗PHCHD的有效方法;肝硬化、血管侵犯、门脉瘤栓是影响PHCHD患者预后的独立危险因素。