Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019204 (hepatocellular carcinoma)
 71,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hepatocellular carcinoma (HCC) is a typical hypervascular tumor. However, the relationship between the vascularity of HCC and the expression of angiogenic factors has not been investigated. In addition, no detailed studies have examined the possible involvement of angiogenic factors in the grade of malignancy of HCC. The aim of this study was to determine which angiogenic factors regulate tumor angiogenesis and contribute to the invasive ability of liver tumors, especially of HCC. Northern blot analysis was used to examine the transcriptional expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (FGF), and acidic FGF in resected surgical specimens (20 HCC and 9 metastatic liver tumors). Correlations between messenger RNA (mRNA) expression and arteriographic findings, as well as histopathological findings, were evaluated. Immunohistochemistry was performed to identify the localization of cells expressing VEGF in HCC. Higher levels of VEGF mRNA were observed in 12 of 20 HCC and 2 of 9 metastatic liver tumors than in corresponding nontumorous tissues. The degree of VEGF mRNA expression was significantly correlated with the intensity of tumor staining in angiograms (P<.01). On immunohistochemical observation, VEGF protein was intensely detected in HCC cells. Furthermore, basic FGF mRNA was detected in 9 of 20 HCC and was related to the capsular infiltration of cancer cells (P<.05). In contrast, no significant difference was observed in the very low levels of acidic FGF mRNA found in the tumorous and nontumorous portions of the liver. In conclusion, these results suggest that VEGF contributes to angiogenesis of liver tumors, whereas basic FGF may be involved in the invasion of HCC into the surrounding tissues.
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PMID:Clinical significance of vascular endothelial growth factor and basic fibroblast growth factor gene expression in liver tumor. 861 24

Vascular permeability factor (VPF)/vascular endothelial growth factor (VEGF) is unique in its ability to promote vascular permeability and endothelial cell growth, and its role in tumor development has received considerable attention. In this report, we describe the elevation of VPF/VEGF transcript expression in human hepatocellular carcinoma. Surgical samples of 23 patients with hepatocellular carcinoma were studied using reverse transcription-PCR analysis. The oligonucleotide primers were designed to amplify all four known splicing variants that could be expressed in the samples studied. Sixteen cases showed VPF/VEGF transcript expression in the tumor (16/23, 69.6%), whereas only 9 of the 23 patients showed it in the corresponding nontumoral part. There was no difference between the pattern of expression of VPF/VEGF isoforms in tumoral and nontumoral tissues. VPF/VEGF mRNA expression in the liver tumors was associated with fibrous capsule formation and septal formation (P < 0.05 respectively, Fisher's exact P test). In situ hybridization confirmed the presence of VPF/VEGF mRNA expression in tumor cells and less intensely in hepatocytes of nontumoral liver. We also found that VPF/VEGF expression in the tumor cell was increased in the area adjacent to necrotic regions (presumably hypoxic regions). As a regulator of vascular permeability and endothelial cell growth factor, VPF/VEGF may play an important role in the development of hepatocellular carcinoma.
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PMID:Expression of vascular permeability factor/vascular endothelial growth factor in human hepatocellular carcinoma. 867 55

The hypoxia-inducible factor-1 (HIF-1) is involved in the induction of oxygen regulated genes such as erythropoietin and vascular endothelial growth factor (VEGF). HIF-1 is a heterodimeric transcription factor consisting of an alpha and a beta subunit. The question of how HIF-1 itself is regulated remains to be elucidated. Studies performed in human Hep3B hepatoma cells suggested that the prevalent mode of HIF-1 action is an increase in HIF-1 alpha steady-state mRNA and protein levels after hypoxic exposure. In contrast to the reported very low basal HIF-1 alpha mRNA levels, however, we detected HIF-1 alpha mRNA in several cell lines cultured under normoxic conditions, although no HIF-1 DNA binding activity was observed. Following hypoxic induction, VEGF mRNA levels and HIF-1 DNA binding activity increased, but HIF-1 alpha mRNA levels remained largely unchanged. One possible explanation for this discrepancy might be that HIF-1 DNA binding activity does not follow HIF-1 alpha mRNA kinetics. We therefore incubated HeLaS3 cells in tonometers for 7.5 minutes up to four hours at either 20% O2 or 0.5% O2. Although there was some variation in HIF-1 alpha mRNA levels, we did not find significant changes over this time frame, suggesting that HIF-1 alpha is not transcriptionally regulated.
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PMID:Hypoxia-inducible factor-1 alpha is regulated at the post-mRNA level. 902 39

We evaluated the effect of nitric oxide (NO) on vascular endothelial growth factor (VEGF) gene expression in human A-172 glioblastoma cells and human HepG2 hepatocellular carcinoma cells. The mRNA level of VEGF increased in response to S-Nitroso-N-acetyl-D,L-penicillamine (SNAP) in both cell lines, and increased in mRNA level well coincided with VEGF protein production in A-172 cells. SNAP at 0.5 mM induced maximal stimulation of 4.4 and 3.7 kb VEGF mRNA expression after 6 h about 11 and 8 fold increase, respectively above control level. Similar VEGF mRNA accumulation was observed also with NOR3, another chemical NO generator. To evaluate the effect of SNAP on VEGF mRNA stability, half-lives of VEGF mRNA were measured in A-172 cells cultured with or without 0.5 mM SNAP and treated with actinomycin D (25 microg/ml). Half-life for VEGF mRNA was found to be prolonged about 2.4 fold by SNAP. VEGF expression induced by SNAP was inhibited by guanylate cyclase inhibitors, methylene blue (10 microM) and LY-83583 (1 microM), and by the protein synthesis inhibitor, cycloheximide (25 microg/ml). These results suggest that induction of VEGF gene expression by NO is mediated through guanylate cyclase activity and requires on-going protein synthesis.
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PMID:Induction of vascular endothelial growth factor by nitric oxide in human glioblastoma and hepatocellular carcinoma cells. 924 80

As in other tumors, the assessment of microvessel density (MVD) in hepatocellular carcinoma (HCC) may be essential to perform an effective anti-angiogenic therapy for this tumor. The relationship between vascular endothelial growth factor (VEGF) and MVD of HCC as well as the surrounding liver remains to be elucidated. In 71 patients who had undergone curative hepatic resection for HCC, MVD and VEGF expressions were evaluated for HCC and the liver by quantitative reverse-transcription polymerase chain reaction (RT-PCR) and/or immunostaining. The intensity and extent of VEGF immunoreactivity were evaluated using a computer image analyzer-cell analysis system (CAS). Angiographic data were re-evaluated and compared with MVD in 50 tumors. Tumoral MVD was significantly correlated with tumor capsule formation (t test, P = .0016). Small HCCs (< or = 2 cm) had a significantly lower MVD compared with moderate-sized HCCs (2-5 cm) (t test, P = .016), and the MVD of large HCCs was relatively lower than that of moderate tumors. Tumor vascularity on angiography was not correlated with the MVD. Neither VEGF mRNA levels nor protein expression in HCC were correlated with the tumoral MVD or any histopathological features of the tumor. However, cirrhotic livers had significantly higher MVD and VEGF expressions compared with noncirrhotic livers (t test, P = .0015 and P = .047, respectively). Only the MVD of tumor was significantly correlated with intrahepatic recurrence (t test, P = .0048) and disease-free survival (DFS) rates (log rank test, P = .0035). Moreover, the MVD was an independent predictor for DFS by multivariate analysis (chi2 test, P = .03). In conclusion, the MVD in HCC may be involved in the dismal prognosis of this tumor, and VEGF may be associated with the angiogenic process of the cirrhotic liver, but not with the angiogenesis of HCC.
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PMID:Clinical significance of microvessel density and vascular endothelial growth factor expression in hepatocellular carcinoma and surrounding liver: possible involvement of vascular endothelial growth factor in the angiogenesis of cirrhotic liver. 962 Mar 26

Vascular endothelial growth factor (VEGF) is an important mediator of vascular development in tumors. We aimed at clarifying the relationship between VEGF mRNA expression and invasion or metastasis of hepatocellular carcinoma (HCC). Reverse transcript-polymerase chain reaction (RT-PCR) was carried out on surgical specimens of 48 patients with HCC. The relative levels of VEGF mRNA expression were measured by determining a ratio between PCR products of VEGF and the endogenous internal standard gene beta-actin. Expression of VEGF mRNA in tumor was found in 76.5% (39/51) of patients, whereas it was 21.69% (11/51) in non tumorous liver. The levels of VEGF mRNA expression in tumors with tumorous emboli and in poor-encapsulated tumors were higher than that without tumorous emboli and in well-encapsulated tumors respectively (p < 0.05 t test). There was no significance in the expression of VEGF mRNA between large HCC (diameter > 5cm) and small HCC (diameter < or = 5cm) (p > 0.05). VEGF may play an important role in the invasion and metastasis of HCC. Angiogenesis in tumor correlates with progression of HCC.
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PMID:Significance of vascular endothelial growth factor mRNA expression in invasion and metastasis of hepatocellular carcinoma. 964 28

Cholangiocarcinoma (CCC) is relatively hypovascular, in contrast to hepatocellular carcinoma (HCC), which is often highly vascular. We investigated if the diminished vascularity of CCC is related to altered expression of thrombospondin-1 (TSP-1), an antiangiogenic factor, and/or vascular endothelial growth factor (VEGF), a potent angiogenic factor, comparing the relationships with those of high- and low-vascular HCC. We also investigated the relationship between the mutation of the p53 gene and TSP-1 expression or VEGF expression. Northern blot analysis and immunohistochemical staining were performed on surgically resected human CCC and HCC. The ratios of TSP-1 mRNA level in cancer cells versus adjacent noncancerous cells (T/N ratios) were significantly higher in CCC (n = 11) than in HCC with high vascularity (n = 15). In contrast, T/N ratios of VEGF mRNA level in CCC (n = 11) were comparable with those in HCC with low vascularity (n = 5). In CCC, the cancer cells and fibroblasts were positively stained with anti-TSP-1 antibody. We observed that T/N ratios of VEGF mRNA level, but not those of the TSP-1 mRNA level, were significantly correlated with vascularity in HCC. The relative increase in TSP-1 and the relative decrease in VEGF in tumors compared with normal tissue may underlie the limited angiogenesis of CCC. The p53 gene did not affect the expression of TSP-1 in CCC or VEGF in HCC.
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PMID:Enhanced expression of thrombospondin-1 and hypovascularity in human cholangiocarcinoma. 982 14

Angiogenic factors such as vascular endothelial growth factor (VEGF) may be involved in neovascularization of malignant tumors. Our aim was to determine whether there is an increased VEGF mRNA expression in liver from patients with HCC and premalignant hepatitis C virus (HCV) with differing severity of inflammation. VEGF mRNA (VEGF165, VEGF189) was detected by reverse transcription and semi-quantitative polymerase chain reaction (RT-PCR) amplification in all liver samples. There was no difference in VEGF mRNA expression ratios (corrected for glyceraldehyde-3-phosphate dehydrogenase) among three groups: steatohepatitis, as a non-malignant non-viral control, 1. 05+/-0.35, n=8; chronic hepatitis C, 0.86+/-0.27, n=18; hepatocellular carcinoma, 1.06+/-0.43, n=10. VEGF mRNA expression was independent of the severity of HCV inflammation estimated by the histological activity index: low HAI (</=4, n=8) vs. high HAI (>/=10, n=10), 0.93+/-0.31 vs. 0.81+/-0.24, p=ns. There was no significant difference in mean VEGF expression between HCC tumor (1.06+/- 0.43) and adjacent tissue (0. 85+/-0.42) although the tumors tended to have higher expression than adjacent non-malignant tissues. In conclusion, all liver samples of steatohepatitis, chronic HCV infection and HCC expressed VEGF mRNA, VEGF mRNA may be uniformly expressed in liver tissue, the level of expression is probably not related to virus infection or the severity of inflammation. Other angiogenic or angiostatic factors might be more involved in angiogenesis in HCC.
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PMID:Vascular endothelial growth factor/vascular permeability factor mRNA expression in patients with chronic hepatitis C and hepatocellular carcinoma. 991 13

Tumor progression is angiogenesis dependent, and vascular endothelial growth factor (VEGF) is a key growth factor in this process. sVEGF concentrations in 44 patients with hepatocellular carcinoma (HCC) and 5 with benign liver lesions were determined with an enzyme-link immunoadsorbent assay system (ELISA). Reverse transcript-polymerase chain reaction (RT-PCR) was carried out on surgical specimens of 51 patients with HCC. The relative levels of VEGF mRNA expression were measured by determining a ratio between PCR products of VEGF and the endogenous internal standard gene b-actin. UEA-1 was histochemically used to count microvascularity in tumor tissue. Elevated sVEGF concentrations were found in patients with HCC (172.84+/-111.75 pg/ml) as compared to individuals with benign liver lesions (95.74+/-36.20 pg/ml, P<.05). Of 44 cases with HCC, sVEGF concentrations in the patients with PV-emboli or with poor-encapsulated tumors were significantly higher than in those without PV-emboli or with well-encapsulated tumors (P<0.05). The expression levels of VEGF mRNA in tumors with PV-emboli and in poor-encapsulated tumors were higher than in those without PV-emboli and in well-encapsulated tumors (P<0.05). Microvascular density in HCC tissues was significantly correlated with the expression levels of VEGF mRNA (P<0.01; r=0.7). Circulating VEGF was derived from HCC tissue. sVEGF concentrations could be a new marker for predicting the angiogenesis, invasion and metastasis of HCC.
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PMID:Serum vascular endothelial growth factor is a predictor of invasion and metastasis in hepatocellular carcinoma. 1074 78

To understand the relationship between the expression of vascular endothelial growth factor (VEGF) and the growth, metastasis of hepatocellular carcinoma (HCC), immunohistochemistry and Northern blot were used to investigate VEGF protein and mRNA in 21 cases of HCC with and without metastasis. VEGF protein was found in 8 of 9 cases with metastasis, whereas only in 4 of 12 cases without metastasis. The positive rate of the former was significantly higher than that in the latter. VEGF mRNA was detectable in both carcinoma and its surrounding liver tissues, but its level in the former was 2-3 times higher than that in the latter. In carcinoma with metastasis, the mRNA level was 5-6 times higher than that without metastasis. It is concluded that VEGF is closely related to the growth of HCC as well as its metastasis and it might be a useful indicator for the metastatic potential of HCC.
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PMID:Expression of vascular endothelial growth factor in hepatocellular carcinoma and its relationship to tumor growth and metastasis. 1080 93


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