Abnormal beta-catenin gene expression with invasiveness of primary hepatocellular carcinoma in China

AIM: To study the abnormal expression of beta-catenin gene and its relationship ith invasiveness of primary hepatocellular carcinoma among Chinese people. METHODS: Thirty-four hepatocellular carcinoma (HCC) specimens and adjacent para-cancerous tissues, 4 normal liver tissues were immunohistochemically stained to study subcellular distribution of beta-catenin. Semiquantitive analysis of expression of beta-catenin gene exon 3 mRNA was examined by RT-PCR and in situ hybridization. The relationship between expressions of both beta-catenin protein, mRNA and clinicopathological characteristics of HCC was also analyzed. RESULTS: Immuno-histochemistry showed that all normal liver tissues and para-cancerous tissues examined displayed membranous type staining for beta-catenin protein, occasionally with weak expression in the cytoplasm. While 21 cases (61.8%) of HCC examined showed accumulated type in cytoplasms or nuclei. The accumulated type Labling Index (LI) of cancer tissue and para-cancerous tissue was (59.9 +/- 26.3) and (18.3 +/- 9.7) respectively (P<0.01). Higher accumulated type LI was closely related with invasiveness of HCC. Results of RT-PCR showed the beta-catenin gene exon 3 mRNA Expression Index (EI) of 34 HCCs was higher than that of para-cancerous tissue and normal liver tissue. Using in situ hybridization, the signal corresponding to beta-catenin gene exon 3 mRNA was particularly strong in cytoplasm of HCC when compared with those of para-cancerous and normal liver tissues. Over expression of beta-catenin exon 3 was also found to be correlated with high metastatic potential of HCC. CONCLUSION: Abnormal expression of beta-catenin gene may contribute importantly to the invasiveness of HCC among Chinese people.     

Abnormal β-catenin gene expression with invasiveness of primary hepatocellular carcinoma in China

AIM To study the abnormal expression of β-catenin gene and its relationship with invasiveness of primary hepatocellular carcinoma among Chinese people. METHODS Thirty-four hepatocellular carcinoma (HCC) specimens and adjacent para-cancerous tissues, 4 normal liver tissues were immunohistochemically stained to study subcellular distribution of β-catenin. Semiquantitive analysis of expression of β-catenin gene exon 3 mRNA was examined by RT-PCR and in situ hybridization. The relationship between expressions of both β-catenin protein, mRNA and clinicopathological characteristics of HCC was also analyzed. RESULTS Immunohistochemistry showed that all normal liver tissues and para-cancerous tissues examined displayed membranous type staining for β-catenin protein,occasionally with weak expression in the cytoplasm.While 21 cases (61.8%) of HCC examined showed accumulated type in cytoplasms or nuclei. The accumuled type Labling Index (LI) of cancer tissue and paracancarous tissue was (59.9 ± 26.3) and (18.3 ± 9.7)respectively (P＜0.01). Higher accumulated type LI was closely related with invasiveness of HCC. Results of RTPCR showed the β-catenin gene exon 3 mRNA Expression Index (El) of 34 HCCs was higher than that of paracancerous tissue and normal liver tissue. Using in situ hybridization, the signal corresponding to β-catenin gene exon 3 mRNA was particularly strong in cytoplasm of HCC when compared with those of para-cancerous and normal liver tissues. Over expression of β-catenin exon 3 was also found to be correlated with high metastatic potential of HCC. CONCLUSION Abnormal expression of β-catenin gene may contribute importantly to the invasiveness of HCC among Chinese people.     

Inhibition mechanism of a newly cloned candidate tumor suppressor gene JST during hepatocarcinogenesis and its abnormal expression in human hepatocellular carcinoma from Qidong liver cancer risk area, China

BACKGROUND/AIMS: To study inhibition effect of a newly cloned candidate tumor suppressor gene (JST) during hepatocarcinogenesis and its normal expression in human hepatocellular carcinoma from Qidong liver cancer risk area, China. METHODOLOGY: By preparing rabbit anti-human JST polyclonal antibody, constructing of JST frameshift mutant and exploring RT-PCR, in situ hybridization, immunohistochemistry, Western blot, Northern blot, cDNA expression microarray, co-immunoprecipitation and the tumorigenicity assay in vivo and in vitro, gene treatment, etc, JST gene expression and inhibition tumor growth effects were analyzed, including 150 pairs of HCC specimens and their adjacent para-cancerous tissues, 8 cases of normal liver tissues and QGY7701, HepG2, Hep3B cell line. Its relationship with the invasiveness of HCC from Qidong was also investigated. RESULTS: Our results showed that there is expression difference for JST between liver cancer and para-cancerous tissue and the results of RT-PCR, in situ hybridization, immunohistochemistry, Western blot, Northern blot suggested that it is a down-regulation gene. The labeling index (LI) of cancer tissue and para-cancerous tissue was (70.2+/-8.7) and (9.4+/-2.8) respectively (p<0.01), lower LI was closely related with invasiveness of HCC, decreased expression of JST was also shown by Western blotting. Results of RT-PCR showed the JST gene expression index (EI) of HCCs was lower than that of para-cancerous tissue and normal liver tissue and there are some sequence differences between cancer and para-cancerous tissues. Northern blot showed JST having down-regulation expression among 92.20% (138/150) of patients. Using in situ hybridization, the signal corresponding to JST mRNA was particularly weak in cytoplasm of HCC when compared with those of para-cancerous and normal liver tissues. Less expression of JST was also found to be correlated with high metastasis potentiality of HCC. JST overexpression inhibits DNA synthesis and apoptosis in QGY7701 cells. QGY7701 cell transfected with JST is more inhibited in soft agar than that of vector transfected control cells (p<0.01) or QGY7701 cells stably transfected with the JST frameshift mutant. The tumor formation is more inhibited in the QGY7701-pcDNA3.1-JST group than that in the QGY7701-pcDNA3.1, QGY7701-pcDNA3.1-JST frameshift mutant group. cDNA expression microarray showed expression differences of 10% (20/200,18 up-regulation; 2 up-regulation) tumor genes were considered significant between QGY7701-pcDNA3.1-JST and QGY7701-pcDNA3.1. Using a co-immunoprecipitation approach, intracellular binding of JST and p53 was found. Higher levels of p53 were detected following infection with pcDNA3.1-JST when compared with pcDNA3.1. Induction of FasL could be demonstrated in Hep3B and in HepG2 cells following transfection pcDNA3.1-JST, but not following transfection pcDNA3.1. CONCLUSIONS: JST is a putative tumor suppressor gene. Overexpression of JST gene may contribute to inhibiting the occurrence, advancement and invasiveness of HCC from Qidong, a high risk area in China.     

CyclinD1、CyclinE、CDK6在原发性肝细胞癌中的表达

探讨细胞周期调控因子CyclinD1、CyclinE、CDK6在原发性肝细胞癌中的表达及意义。应用免疫组织化学、原位分子杂交和细胞图象分析技术检测原发性肝细胞癌组织及其对应的癌旁肝组织(各20例)、正常肝组织(5例)中CyclinD1、CyclinE和CDK6mRNA表达情况。结果显示:CyclinD1、CyclinE和CDK6mRNA在肝细胞癌组织中呈阳性表达,阳性率分别为70%、75%和25%,正常肝组织呈阴性表达;肝细胞癌组织中CyclinD1和CyclinE的阳性表达与癌旁肝组织、正常肝组织相比,差异均有显著性意义(P<0.05);CyclinD1和CyclinE的过表达在肝细胞癌的发生和发展中起着重要作用。     

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.     

用cDNA阵列技术研究黄曲霉毒素B1诱发树鼩肝癌形成过程中的基因变化

目的 对树鼩肝癌形成过程中的基因表达差异进行动态分析,探讨肝癌发生的分子机制。 方法用cDNA阵列技术,将2例黄曲霉毒素B1诱发的树鼩肝癌组织分别与其癌旁组织和其肝癌形成前的活检肝组织、实验前对照和同期对照肝组织进行基因表达水平的6种比较分析。结果 不同的比较方式所显示的差异表达的基因谱不同,可归为4类:癌组织表达高于癌旁组织、癌旁组织表达高于癌发生前肝的组织;癌与癌旁表达水平相仿,但高于癌发生前的肝组织;癌组织下调,低于癌旁组织;癌发生前表达上调,在癌发生后表达下调。 结论 对肝癌形成过程中不同时期的肝组织基因表达水平进行动态对比分析,有助于阐明肝癌发生的分子机制并最终筛选出与肝癌发生有关的关键基因。     

Tissue microarray for high-throughput analysis of gene expression profiles in hepatocellular carcinoma

AIM: To study the expression profiles of HBsAg, HBcAg, p21WAF1/CIP1 (p21), Rb genes in hepatocellular carcinoma (HCC) and to investigate their roles in the hepatocar-cinogenesis. METHODS: HCC tissue microarray containing 120-min tissues of 40 HCC cases was constructed. HBsAg, HBcAg, p21 and Rb proteins were immunohistochemically stained by streptavidin-peroxidase conjugated method (S-P). The expression loss of these genes in cancerous, para-cancerous tissues and adjacent normal liver tissues of 40 HCCs were comparatively examined. RESULTS: The positive rate of HBsAg expression in cancerous tissues of 40 HCCs was 7.5%, which was lower than that in para-cancerous and adjacent normal liver tissues (X2=12.774, P<0.01; X2=18.442, P<0.01). The positive rate of HBcAg expression in cancerous tissues of 40 HCCs was 20.0%, which was also lower than that in para-cancerous and adjacent normal liver tissues (X2=9.482, P<0.01; X2=14.645, P<0.01). p21 protein deletion rate in cancerous tissues of 40 HCCs was 27.5%, which was higher than that in para-cancerous and adjacent normal liver tissues (X2=7.439, P<0.01; X2=11.174, P<0.01). p21 protein deletion correlated remarkably with the pathological grade of HCC (X2=0.072, P<0.05). Rb protein deletion rate in cancerous tissues of 40 HCCs was 42.5%, which was also higher than that in para-cancerous and adjacent normal liver tissues (X2=10.551, P<0.01; X2=18.353, P<0.01). Rb protein deletion rate did not correlate remarkably with tumor size or pathological grade of HCC (X2=0.014, P>0.05; X2=0.017, P>0.05). CONCLUSION: Expression deletion of HBsAg, HBcAg, p21 and Rb proteins in HCCs may play important roles in the carcinogenesis of HCC. Tissue microarray is an effective high-throughput technique platform for cancer research.     

Cartilage oligomeric matrix protein expression in hepatocellular carcinoma and the cirrhotic liver

BACKGROUND: Cartilage oligomeric matrix protein (COMP) is the fifth member of the thrombospondin family of extracellular, calcium-binding proteins. It was initially isolated and characterized in cartilage tissue, where it is thought to contribute to the extracellular matrix composition and cell-extracellular matrix interaction. In the present study the expression of COMP was investigated in normal liver (n=19), liver cirrhosis (n=14) and hepatocellular carcinoma (HCC; n=16) tissues, both at the mRNA and protein level. METHODS AND RESULTS: By northern blot and western blot analysis, COMP was absent or rarely expressed in the normal liver and liver cirrhosis tissues, but significantly overexpressed in HCC tissue samples. The COMP mRNA overexpression in HCC was not related to the clinical stage or tumor grade. By in situ hybridization and immunohistochemistry analysis, COMP mRNA and protein expression were localized within the cytoplasm of the tumor cells. CONCLUSION: COMP is highly expressed within the tumor cells of HCC, suggesting that COMP might play a role in the pathophysiology of this disease.     

原发性肝细胞癌及癌旁组织中环氧合酶-2的表达及其意义

目的：研究人原发性肝细胞癌（HCC）组织和癌旁非瘤组织中的环氧合酶－2（COX－2）蛋白及基因表达情况,方法：采用免疫组织化法和原位分子杂交法,研究27对原发性肝细胞癌及癌旁非肿瘤组织,5例正常肝组织中COX－2的蛋白和基因表达,结果：高分化HCC中COX－2蛋白表达显著高于中分化和低分化HCC（P分别＜0．05）以及癌旁组织和正常组织（P分别＜0．01）,癌旁组织的COX－2表达显著高于正常组织（P＜0．05）,癌旁组织,中分化和低分化HCC之间COX－2的表达强度差异无显著性（P＞0．05）,在COX－2蛋白阳性的肝癌细胞和癌旁肝细胞胸胞胞质中可见到COX－2mRNA呈阳性表达,结论：COX－2的过度表达可能参与了高分子HCC的致癌过程。     

PTEN和磷酸化Smad2在原发性肝癌中的表达

目的探讨肝癌等组织中10号染色体缺失的磷酸酶及张力蛋白同源物（PTEN）和磷酸化Smad2（P-Smad2）表达的意义。方法采用免疫组织化学技术检测肝癌组织、癌旁肝组织和非癌性肝组织中P-Smad2和PTEN的表达。结果31份肝癌组织中PTEN表达以细胞质和细胞膜明显,细胞核基本不表达；25份癌旁及13份非癌性肝组织中则以细胞核和细胞质强表达,细胞膜弱表达。PTEN在肝癌组织的表达率（64．5％）低于癌旁肝组织（96．0％）和非癌性肝组织（100．0％）,表达强度（4．19±3．31）低于癌旁肝组织（7．88±0．93）和非癌性肝组织（7．77±0．93）,差异均有统计学意义（P＜0．05）。不同病理分级的肝癌组织中PTEN的表达率差异无统计学意义（P＞0．05）,≥Ⅱ级的肝癌组织细胞质表达强度（3．07±2．87）低于＜Ⅱ级（5．80±3．12）的肝癌组织（P＜0．05）。癌旁有、无肝内血管癌栓的肝癌组织中,PTEN表达率分别为45．5％和85．7％,表达强度分别为3．00±3．46和6．28±2．37,差异均有统计学意义（P＜0．05）。PTEN在肝细胞的表达定位与病理类型呈负相关（r=0．34,P＜0．01）,与肝内血管癌栓呈负相关（r=-0．43,P＜0．05）。非癌性肝组织、癌旁肝组织和病理分级＜Ⅱ级的肝癌组织中,P-Smad2表达以细胞核和细胞质明显,≥Ⅱ级的肝癌组织中则以细胞核为主。P-Smad2在肝细胞的表达定位与病理类型呈正相关（r=0．22,P＜0．05）,P-Smad2在细胞核的表达强度。肝癌组织与癌旁肝组织的差异无统计学意义,也与肝内血管有无癌栓无关。肝癌组织中PTEN和P-Smad2表达呈负相关（r=-0．73,P＜0．01）。结论PTEN的表达、强度以及和P-Smad2的核、质转位可能与肿瘤的发展和恶化有关,二者可能存在相互作用,共同参与肝癌的发生机制。     

肝细胞癌变过程中核因子-κB及其基因的动态表达与定量分析

目的 观察肝癌形成过程中核因子-κB(NF-κB)及NF-κB mRNA动态表达与作用机制.方法 雄性SD大鼠以2-乙酰氨基芴制备肝癌模型,经病理组织学分析肝细胞形态学变化,定量观察NF-κB动态变化,以巢式PCR分析NF-κB mRNA的表达.并以自身配对法收集经手术切除后的肝癌及其癌周组织,定量分析肝癌组织中NF-κB表达及病理学特征. 结果诱癌后在肝细胞呈颗粒样变性,不典型增生,肝细胞癌形成,NF-κB及基因表达呈梯度增加.NF-κB阳性表达呈棕黄色颗粒状染色,癌组织NF-κB点灶状表达,定位于胞质和细胞核,癌周组织NF-κB主要定位于胞质,未见细胞核阳性.癌变过程中NF-κB mRNA表达明显增强.人肝癌组织NF-κB(69.3±40.2)pg/mg,明显高于癌周组织(21.0±17.2)pg/mg(t=6.54,P＜0.01).癌组织NF-κB表达阳性率为100%,癌周组织为68.6%(X2=13.05,P＜0.01).其表达与肿瘤分化程度,肿瘤数目和肿瘤直径无关. 结论 NF-κB异常表达与肝癌的发生发展有关,表达抑制有助于肝痛治疗.     

Pathomorphological study on location and distribution of Kupffer cells in hepatocellular carcinoma

AIM: To clarify the location and distribution of Kupffer cells in hepatocellular carcinoma (HCC), and to investigate their role in hepatocarcinogenesis.METHODS: Kupffer cells were immunohistochemically stained by streptavadin-peroxidase conjugated method (S-P). The numbers of Kupffer cells in cancerous, para-cancerous and adjacent normal liver tissues of 48 HCCs were comparatively examined.RESULTS: The mean number of Kupffer cells in cancerous,para-cancerous and adjacent normal liver tissues was 12.7±6.8, 18.1±8.2 and 18.9±7.9 respectively. The number of Kuppfer cells in cancerous tissues was significantly lower than that in para-cancerous tissues (t=2.423, P＜0.05) and adjacent normal liver tissues (t=2.52t, P＜0.05). As tumor size increased, the number of Kupffer cells in cancerous tissues significantly decreased (F=4.61, P＜0.05). Moreover,there was also a significant difference in the number of Kupffer cells among well-differentiated, moderately-differentiated and poorly-differentiated cases(F＝4.49, P＜0.05).CONCLUSION: This study suggests that decrease of Kupffer cells in HCCs may play an important role in the carcinogenesis of HCC, the number of Kupffer cells in HCC is closely related to the size and differentiation grade of the tumor.     

Determination of High Mobility Group A1 (HMGA1) Expression in Hepatocellular Carcinoma: A Potential Prognostic Marker

Our objective was to investigate the expression of HMGA1 mRNA and protein in hepatocellular carcinoma (HCC) and the correlation between its expression and clinical pathological characteristics and prognosis. HMGA1 expression was determined at both the mRNA level and the protein level in 30 HCC tissues and their corresponding paracancer liver tissues (PCLTs) and 2 normal liver tissues by RT-PCR and IHC. Follow-up study was done on the 30 patients involved in this research. HMGA1 mRNA was detected in nine cases of HCC tissues and two PCLTs, for a positivity rate of 30% and 6.7%, respectively (P < 0.05), whereas no HMGA1 mRNA expression was found in normal liver tisssues. Clinicopathological analysis revealed that HMGA1 mRNA expression was significantly correlated with Edmondson's grade (P < 0.05). HMGA1 protein was detected in four HCC tissues by IHC and located mainly in the nuclei; no positive staining was found in PCLTs. Follow-up study showed that HMGA1 mRNA-positive patients had a higher risk of recurrence/metastasis and a shorter survival than negative cases (P < 0.05). Our findings indicate that HMGA1 may be involved in the carcinogenesis and invasiveness of HCC and the determination of HMGA1 can be of great value in predicting the prognosis of patients with HCC. This work was supported in part by National Key Technologies R&D Program Grant 2001BA703B04 and National Basic Research Program Grant 2004CB720303, Ministry of Science and Technology, People's Republic of China.