Hepatocellular carcinoma (HCC) is one of the most malignant human tumours because of its high incidence of metastasis. The mechanisms underlying the metastasis of HCC, however, remain poorly understood. In this study, we performed cDNA microarray analysis to profile gene expression patterns in two subtypes of HCC, solitary large HCC (SLHCC) and nodular HCC (NHCC), which differ significantly in the incidence of metastasis. Among 668 genes that were differentially expressed, we focused on RhoC, whose expression was significantly decreased in SLHCC compared to NHCC. The expression of RhoC in HCC and pericarcinomatous liver tissues (PCLT) was analysed at both the mRNA and protein levels by reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting. In addition, immunohistochemistry was also performed on 94 cases of HCC with follow-up information. Collectively, our data indicate that the expression of RhoC significantly increased in HCC compared to PCLT; extrahepatic metastatic lesions expressed significantly higher levels of RhoC than the corresponding intrahepatic HCC tissues. There is a highly significant correlation of the RhoC expression levels with tumour vein invasion, number of tumour nodes and the status of differentiation. Significantly, the HCC patients with RhoC-positive expression had shorter survival than those with RhoC-negative expression. Together, our findings suggest a strong correlation between the expression of RhoC and HCC metastasis, implicating RhoC as a potential prognosis marker and therapeutic target for HCC.

AIM: To investigate the expression of cysteine-rich61 (Cyr61), connective tissue growth factor (CTGF) and nephroblastoma overexpressed gene (Nov) in hepatocellular carcinoma (HCC), and to evaluate the relationship between Cyr61, CTGF and Nov genes expression with invasion and metastasis of HCC. METHODS: Thirty-one HCC specimens were divided into small hepatocellular carcinoma (SHCC), nodular hepatocellular carcinoma (NHCC), solitary large hepatocellular carcinoma (SLHCC) according to their diameter and number of nodes. Reverse transcription polymerse chain reaction (RT-PCR) was used to detect the mRNA expression levels of Cyr61, CTGF and Nov genes in 31 resected specimens of hepatocellular carcinoma and para-cancerous normal liver tissues semi-quantitatively and the relation between their expression levels and clinical pathological parameters were compared. RESULTS: The expressions of Cyr61 and CTGF mRNA in carcinoma tissues were significantly higher than those in para-cancerous normal liver tissues (P<0.01). The expressions of Cyr61 and CTGF mRNA in HCC with venous invasion were higher than those in HCC without venous invasion. CTGF expression in HCC Edmondson's grade III-IV was significantly higher than that in HCC Edmondson's grade I-II (P=0.022). There was no obvious correlation between Nov mRNA and clinical-pathological features. Compared to NHCC, SLHCC had better cell differentiation, easier capsule formation, less microscopic venous invasion, milder liver cirrhosis. The expressions of Cyr61 and CTGF mRNA in NHCC were significantly higher than those in SLHCC and SHCC. CONCLUSION: Cyr61 and CTGF genes may play an important role in hepatocellular carcinogenesis and correlate with recurrence and metastasis of hepatocellular carcinoma. SLHCC has better biological behaviors than NHCC.

AIM: To investigate the expression of hypoxia-inducible factor (HIF)-2a/endothelial PAS domain protein 1 (EPAS1) in hepatocellular carcinoma (HCC). METHODS: Expression of HIF-2a/EPASl was investigated immunohistochemically on paraffin-embedded sections from 97 patients with HCC. To further confirm that HIF-2a/EPASl in HCC tissues also correlated with angiogenesis, a parallel immunohistchemistry study of vascular endothelial growth factor (VEGF) was performed on these 97 cases. RESULTS: HIF-2a/EPASl could be detected in 50 of 97 cases (51.6%), including 19 weakly positive (19.8%), and 31 strongly positive (31.1%), the other 47 cases were negative (48.4%). The expression of HIF-2a/EPASlwas significantly correlated with tumor size, capsule infiltration, portal vein invasion, and necrosis. A parallel immunohistochemical analysis of VEGF demonstrated its positive correlation with capsule infiltration, portal vein invasion, and HIF-2a/EPASl overexpression, which supported the correlation of HIF-2a/EPASlup-regulation with tumor angiogenesis. No apparent correlation was observed between HIF-2a/EPASl and capsular formation, presence of cirrhosis, and histological grade. CONCLUSION: HIF-2a/EPASl is expressed in most of HCC with capsular infiltration and portal vein invasion, which indicates a possible role of HIF-2a/EPASl in HCC metastasis.

目的 建立化疗药物丝裂霉素诱导肝癌细胞凋亡的模型，初步探讨在该凋亡过程中重要凋亡相关基因p53和bcl-2的调控作用。方法 用丝裂霉素诱导人肝癌细胞系HepG2凋亡，荧光显微镜和透射电镜观察肝癌细胞的形态学改变，琼脂糖凝胶电泳检测凋亡细胞DNA片段的梯状条带，用流式细胞仪免疫荧光法检测凋亡不同时期P53和Bcl-2蛋白的表达量。结果 8mg/ml丝裂霉素作用12，24，48h后，P53蛋白表达量明显增高，尤以12h明显，而后逐渐下降。Bcl-2蛋白在整个凋亡过程中无明显变化。结论 在化疗药物丝裂霉素诱导肝癌细胞凋亡过程中，p53基因参与了调控，并为凋亡信号传导途径中的早期事件。丝裂霉素诱导的肝癌细胞凋亡途径为p53依赖方式，而在该凋亡过程中，bcl-2基因的调控并不重要。

目的 研究孤立性原发性大肝癌的分子病理特征。方法 比较20例孤立性大肝癌与13例小肝癌、10例结节性肝癌的病理特征，并且采用免疫组织化学方法检测三组肝癌组织中与恶性肿瘤侵袭转移有关分子标志物的表达情况，包括PTEN蛋白、Survivin 蛋白、整合素αv 亚基、基质金属蛋白酶2（MMP2）以及微血管密度（MVD）。结果 孤立性大肝癌大多有包膜且呈膨胀性生长，肝硬化少，癌细胞分化较结节性肝癌好（P<0.05）。孤立性大肝癌的Survivin蛋白、整合素αv亚基、MMP2的表达及MVD均低于结节性肝癌，而PTEN蛋白明显高于结节性肝癌（P<0.05)，上述指标在孤立性大肝癌组与小肝癌组比较均无统计学差异（P>0.05）。结论 孤立性大肝癌具有特殊的临床和分子病理特征及相对好的肿瘤生物学行为。