UMLS:C0019204 - FACTA Search

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Query: UMLS:C0019204 (hepatocellular carcinoma)
71,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

CD34 has been widely used for the assessment of sinusoid-like neoangiogenesis in hepatocellular carcinoma (HCC). Recently, it was demonstrated that CD34-positive cells isolated from human peripheral blood differentiate into endothelial cells and contribute to neoangiogenesis in adults. We investigated the localization and the substantial role of CD34-positive endothelial cells in the liver with hepatitis C virus (HCV)--associated chronic liver diseases. Liver tissue sections obtained by biopsy from 56 patients with HCV-associated chronic liver diseases by were examined immunohistochemically using anti-CD34, anti-von Willebrand factor (vWF), and anti-vascular endothelial growth factor (VEGF) antibodies. CD34 was stained in the sinusoid, showing dotty, linear, semicircular, or circular patterns. However, sinusoidal expression of vWF was not substantially identified in the same specimens, indicating the existence of sinusoidal CD34-positive but vWF-negative endothelial cells. We classified these cells as CD34 LI and found that CD34 LI was correlated with the expression of VEGF. Among 34 patients with advanced-stage disease, the cumulative incidence of HCC was significantly higher in patients with CD34 LI >or= 12 (n = 16) than in those with CD34 LI < 12 (n = 18; P = .009). Moreover, among several clinicopathologic risk factors, CD34 LI could be recognized as an independently significant factor for development of HCC (relative risk, 7.36; P = .019). We conclude that CD34-positive endothelial cells are regulated by several factors, such as VEGF, and might play a substantial role in hepatocarcinogenesis. Furthermore, high expression of CD34-positive sinusoidal endothelial cells is a risk factor for HCC in patients with HCV-associated chronic liver diseases.
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PMID:High expression of CD34-positive sinusoidal endothelial cells is a risk factor for hepatocellular carcinoma in patients with HCV-associated chronic liver diseases. 1177 70

Hepatocellular carcinoma (HCC) is the most common malignant tumor of males in the world, with an incidence of 1,000,000 new cases a year. It is endemic in Southeast Asia and Sub-Saharan Africa. Risk factors include chronic infection with hepatitis B virus (HBV) and hepatitis C virus (HCV), Aflatoxin B1 uptake, hemochromatosis, and alpha1 -antitripsin deficiency. Epidemiological studies provide evidence for the association of HCC with HBV infection. The incidence of HCC is high in regions hyperendemic for HBV. Chronic carrier state and maternal-infant transmission are important factors in the development of HCC. Evidence of direct oncogenic effect of H BV is well established, HCCs contain viral DNA sequences integrated into hepatocyte DNA that act as random insertional mutagens, and these sites are near genes involved in the control of proliferation and differentiation. The mechanism of hepatitis C virus in hepatocarcinogenesis is still imprecise but a high percentage of cases are related to this virus. Chronic alcohol consumption and cirrhosis are cofactors that increase the development of HCC in patients with chronic viral infection. In experimental carcinogenesis a multipotential element called oval cell proliferates in the early stages. The cellular events are accompanied by increased expression of several growth factors that enhance the survival of carcinogen-activated cells by suppressing apoptosis and increasing elements entering the cell cycle. Hepatic carcinogenesis is a complex process associated with accumulation of genetic and epigenetic changes that run through steps of initiation, promotion and progression. Activation of oncogenes of the "ras" family and others has been detected during chemically-induced HCC in rodents, but there is little evidence of such activation in human tumors. The role of tumor supressor genes such as retinoblastoma (RB) and P53 genes has been documented. Aflatoxin B1 that contaminates foods in endemic areas has a clear role in hepatocarcinogenesis. Metabolites of this toxin promote apurinic sites and G to T mutations in chromosomal DNA, the third base of codon 249 of the P53 gene is preferentially targeted to form aducts with aflatoxin B1, and this mutation has been specifically identified in HBV infection. Histological and cytological criteria for the diagnosis of HCC are well established and are based in architectural and cytological changes. An important issue is the diagnosis of liver "nodules" detected by image, from which small biopsies or aspiration material is obtained. Special studies such as reticulin, CD34, cytokeratin profile, and MOC-31 can be very useful for the differential diagnosis of primary and metastatic tumors. Telomerase activity has been found in HCC and negative in pericancerous tissue. It is more pronounced in poorly differentiated tumors and correlates with factors of clinical importance, such as prognosis and recurrences. Cells of well-differentiated HCC have an ultrastructural appearance similar to normal hepatocytes. During the process of dedifferentiation, there is progressive loss of organization of intracellular organelles. The cell cohesion is lost, intercellular gaps with microvilli appear, the sinusoids become capillarized, and reparative changes are seen in the spaces of Disse. A variety of inclusions, such as Mallory bodies, granular material, secondary lysosomes, and Dubin-Johnson pigment, have been described. Fibrolamellar carcinoma has a characteristic histological picture and ultrastructurally oncocytic features. Neuroendocrine granules and combination of HCC with bile duct carcinoma are seen by electron microscopy.
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PMID:Hepatocellular carcinoma: an update. 1178 14

Hematopoietic stem cells have been identified as multipotent cells that give rise to all adult hematopoietic lineages. Although the hematopoietic lineage is derived from the mesodermal germ layer in the embryo, recent data suggest that bone marrow cells with an antigenic profile consistent with that of hematopoietic stem cells can also differentiate to cell types of the endodermal lineages, such as hepatocytes. However, the molecular mechanisms associated with these events are entirely unknown. For decades, alpha-fetoprotein (AFP) has been used as a differentiation marker for endodermal cells, because it was thought that the transcription of AFP mRNA is tightly regulated in a developmental and tissue-specific process. In this report we describe two new variant forms of AFP transcripts in human hematopoietic progenitors that are not expressed in mature cells. The variant AFP (vAFP) cDNA sequences isolated from a multipotent hematopoietic cell line, K562, revealed that the vAFP differed from the authentic transcript, consisting of 15 exons, by replacing exon 1 of AFP with one or two exons located in the 5'-untranslated region of the AFP gene. In addition to the K562 cell line, vAFP transcripts were detected in normal bone marrow, thymus, and brain but were not detected in normal spleen, intestine, liver, or the hepatocellular carcinoma cell line, HepG2. This suggests expression in normal hematopoietic progenitors. This hypothesis was confirmed by the finding that CD34(+)Lin(-) hematopoietic progenitor cells purified from cord blood by flow cytometric sorting also expressed the variant transcripts. These results suggest that some hematopoietic progenitors are in a state that permits them to express certain types of transcripts that have been considered unique to endoderm.
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PMID:Variant forms of alpha-fetoprotein transcripts expressed in human hematopoietic progenitors. Implications for their developmental potential towards endoderm. 1200 69

To explore the relationship of angiogenesis-related angiopoietin-2 gene and its receptor Tie2 with angiogenesis and the biology of hepatocellular carcinoma (HCC), angiopoietin-2 gene, Tie2 and CD34 protein expression in 22 resected HCC, 8 cirrhotic and 8 control liver specimens were investigated by in situ hybridization and immunohistochemistry respectively, and the level of angiopoietin-2 and Tie2 expression in HCC were compared in terms of tumor biological parameters. It was found that CD34 was not expressed in control liver, expressed scarcely in cirrhotic liver (17.8 +/- 13.5/HP), but intensively expressed in HCC (86.3 +/- 34.8/HP, P < 0.01). Tie2 receptor was not expressed in controls, expressed at low level in cirrhotic liver (11.3 +/- 8.7/HP), while strongly positive in the microvascular endothelia of HCC (52.4 +/- 16.7/HP, P < 0.01). The level of Tie2 receptor expression in HCC was closely related with tumor diameter, angiogenesis and portal invasion. Angiopoietin-2 gene was not expressed in control liver, expressed mildly in cirrhotic liver (11.2 +/- 9.7/HP), but extensively in tumor zone (36.4 +/- 17.5/HP), the level of angiopoietin-2 expression was closely related with angiogenesis, portal invasion and histological grading of HCC. It is concluded that angiogenesis is increased in HCC; angiopoietin-2/Tie2 expression in human hepatic carcinoma is closely related with angiogenesis, which are probably involved in the HCC angiogenesis regulation, promoting the development and metastasis of human hepatic cancer.
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PMID:Expression of angiopoietin-2 gene and its receptor Tie2 in hepatocellular carcinoma. 1253 84

In this study, we examined the expression of inducible nitric oxide synthase (iNOS) and vascular endothelial growth factor (VEGF) by immunohistochemical staining in 76 tissue sections collected from hepatocellular carcinoma (HCC) patients undergoing hepatectomy. Microvascular density (MVD) was determined by counting endothelial cells immunostained using anti-CD34 antibody. We performed DNA-flow cytometric analyses to elucidate the impact of iNOS and VEGF expression on the cell cycle of HCC. Most of the HCC cells that invaded stroma were markedly immunostained by iNOS antibody. The iNOS stain intensity of the liver tissue close to the tumor edge was stronger than that of HCC tissue, and the strongest was the hepatocytes closer to the tumor tissue. However, iNOS expression in 10 normal hepatic samples was undetectable. VEGF positive expression ratio was 84.8% in iNOS positive expression cases, and the ratio was 35.3% in negative cases. There was significant correlation (P = 0.000) between iNOS and VEGF expression. Moreover, iNOS expression was significantly associated with bcl-2 and MVD, but without p53 expression. DNA-flow cytometric analyses showed that combined expression of iNOS and VEGF had significant impact on the cell cycle in HCC. PI (Proliferating Index) and SPF (S-phase fraction) in the combined positive expression of iNOS and VEGF group was significantly higher than that in the combined negative group. The present findings suggested that iNOS expression was significantly associated with angiogenesis, bcl-2 and cell proliferation of HCC.
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PMID:Inducible nitric oxide synthase expression is related to angiogenesis, bcl-2 and cell proliferation in hepatocellular carcinoma. 1265 38

Human hepatocellular carcinoma (HCC) is a hypervascular tumor but the mechanisms underlying the process of angiogenesis are not fully understood. Angiopoietins (Ang) have been recently identified as ligands for Tie-2 receptor and are thought to be important factors in vascular maturation and stability during angiogenesis. In this study, we investigated the expression of Ang-1, Ang-2, Tie-2, and vascular endothelial growth factor (VEGF) in surgically resected specimens from 46 patients with HCC to determine their potential role in tumor angiogenesis and its progression. VEGF messenger RNA (mRNA) was significantly up-regulated in HCC compared to normal liver tissue from patients with hepatic metastases. No differences were found between HCC and adjacent liver tissue. Meanwhile, Ang-2 mRNA expression in HCC was significantly increased when compared to adjacent liver tissue. On the other hand, Ang-1 and Tie-2 mRNA expression in HCC was not different from that in adjacent liver tissue. Immunohistochemical staining also showed increased Ang-2 protein in HCC. Furthermore, a high Ang-2/1 mRNA ratio in HCC was closely associated with tumor portal vein invasion, tumor diameter, and the microvessel density level as assessed by CD34 immunostaining. With regard to prognosis, the survival time for patients in the high Ang-2/1 mRNA ratio group was significantly poorer when compared with the low Ang-2/1 mRNA ratio group. In conclusion, an increased expression of Ang-2/1 in the presence of VEGF may play a critical role in promoting tumor angiogenesis and progression in human HCC.
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PMID:Angiopoietins and Tie-2 expression in angiogenesis and proliferation of human hepatocellular carcinoma. 1271 91

Hepatoblastoma, a childhood tumor of the liver, is composed of epithelial and mesenchymal elements in varying proportions and at various stages of differentiation. The epithelial element recapitulates the stages of hepatocyte development from the primitive blastema through embryonal hepatocytes to fetal hepatocytes. The blastemal or undifferentiated cells have been postulated to represent neoplastic hepatocyte progenitor cells. In this study, we examine the immunophenotype of the various epithelial cells of hepatoblastoma with special emphasis on the small undifferentiated cell component and compare it with that of adult hepatocytes and hepatic stem (oval) cells. Putative stem cells in the liver can express all of the following markers: alpha-feto protein, CK19 (OV-6), chromogranin A, Bcl-2, HepPar-1, and alpha1 microglobulin. The latter, like alpha-feto protein, is a plasma protein synthesized by hepatocytes. Both alpha1 microglobulin and HepPar-1 are expressed in fetal liver cells as early as 7 weeks of intrauterine life. They are also expressed in hepatocellular carcinoma and in hepatocytic cell lines derived from normal fetal or adult liver. Formalin-fixed, paraffin-embedded archival tissues from 10 predominantly epithelial hepatoblastomas were immunostained with antibodies directed against CD 34, alpha1 microglobulin, Bcl-2, HepPar 1, and CK19 using the avidin-biotin-peroxidase method. The undifferentiated small cell component did not express any of the markers studied, namely, Bcl-2, HepPar-1, alpha(1) microglobulin, CD34, or CK19. Hepatocyte-like cells were alpha1 microglobulin- and HepPar-1-positive, with the intensity of staining correlating with the degree of hepatocytic differentiation. Bcl-2 expression was restricted to areas of ductular differentiation. CK19 was detected in foci that showed duct formation. The small cells of hepatoblastoma did not express HepPar-1, Bcl-2, CK19, alpha1 microglobulin, or CD34, markers that characterize the immunophenotype of hepatic stem cells ("oval" cells). Thus, this observation raises the following questions: (1) is "hepatoblastoma" a misnomer? (2) is the expression of tumor antigens dysregulated in hepatoblastoma? (3) does the liver have two different types of progenitor cells, oval cells and blastemal cells, with differing immunophenotypes? and (4) do the blastemal cells, rather than oval cells, represent the more primitive progenitor cells of the liver?
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PMID:Small cells in hepatoblastoma lack "oval" cell phenotype. 1367 57

A 57-year-old woman was referred to our hospital because of a liver mass detected by computed tomography. She had taken oral contraceptives for only one month at the age of thirty. Physical examination revealed no abnormalities, and laboratory data, including hepatic function tests, were within the normal range, with the exception of elevated levels of those serum proteins induced by the absence of vitamin K or by raised levels of the antagonist (PIVKA)-II (3,502 AU/ml). Abdominal ultrasonography revealed a hyperechoic mass measuring 10 X 10 cm in the left posterior segment of the liver. Because hepatocellular carcinoma could not be completely excluded, this mass was resected. The tumor consisted of sheets of uniform cells with clear cytoplasm, perinuclear eosinophilic granules and round nuclei. These histological findings were consistent with liver cell adenoma. Background hepatic tissue appeared normal. After resection of the tumor, serum PIVKA-II fell to within the normal range. An area of hepatocellular carcinoma (HCC) with a mid-trabecular pattern was immunohistochemically found, which was positive for PIVKA-II. Sinusoidal endothelial cells were CD34-positive, containing scattered PIVKA-II positive cells. This tumor was therefore finally diagnosed as liver cell adenoma with focal malignant transformation to HCC.
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PMID:Liver cell adenoma with malignant transformation: a case report. 1456 19

Differentiating primary and metastatic hepatic malignancies can be diagnostically challenging in fine-needle aspiration cytology (FNAC). We compared four immunohistochemical (IHC) markers, pCEA, CD10, HepPar1, and CD34, in differentiating hepatocellular carcinoma (HCC) from metastatic carcinoma (MC) in FNAC specimens. Sixty cases of liver FNAC with their corresponding cell blocks were retrieved from the hospital computer system, including 30 HCC and 30 MC (15 colon, 10 breast, and 5 pancreas). The diagnoses were confirmed by clinical follow-up and surgical resection or core needle biopsy. The direct cytologic smears were air-dried and Diff-Quik-stained, and alcohol-fixed and Papanicolaou-stained. Cell block sections from the aspirates were immunostained for pCEA, CD10, HepPar1, and CD34. IHC on cytologic smears for HCC was performed on 10 cases and compared with the cell block results. In HCC, CD10, and pCEA demonstrated the characteristic canalicular staining in 23/30 (77%) and 24/30 (80%) of the cases, respectively; however, none of the MC showed a canalicular staining pattern. HepPar1 was positive in 26/30 (87%) of the HCC cases and one MC. CD34 stained sinusoidal endothelial cells in 27/30 (90%) cases of HCC and six MC. Our results demonstrate that the canalicular staining pattern for CD10 and sinusoidal staining pattern of CD34 are very specific, in addition to the high specificity and sensitivity of HepPar1 for HCC. Cell blocks were more informative in demonstrating the characteristic architecture and immunostaining pattern of the malignancy than the cytologic smears. An IHC panel consisting of pCEA, CD10, HepPar1, and CD34 is useful for confirming HCC in FNAC of the liver.
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PMID:Diagnostic value of HepPar1, pCEA, CD10, and CD34 expression in separating hepatocellular carcinoma from metastatic carcinoma in fine-needle aspiration cytology. 1469 37

Evidence indicates that cyclooxygenase (COX)-2-derived prostaglandins (PGs) contribute to tumor growth by inducing angiogenesis. We investigated the role of COX-2 in hepatitis B virus (HBV)-associated hepatocellular carcinoma (HCC). COX-2 and vascular endothelial growth factor (VEGF) expressions were examined by immunohistochemistry in 24 HBV-associated HCC. Tumor micro-vessel density (MVD) was assessed using CD34 immunohistochemistry. Hep3B HCC cell line, which carries integrated HBV genome, was stably transfected with human COX-2 cDNA. COX-2 and VEGF expressions were determined by Western blot while PG level was determined by ELISA. The effects of PGs on VEGF expression were also investigated. Expression of COX-2 and VEGF in HCC cells were observed in 19 (79%) and 16 (67%) cases, respectively. Well-differentiated HCC expressed COX-2 more strongly than less-differentiated HCC (p<0.001). COX-2 expression was found to correlate with VEGF expression and MVD (p=0.003 and 0.004, respectively). COX-2 overexpressing Hep3B clone had higher VEGF expression as compared to non-COX-2 expressing clone and parental cells. Treatment of the COX-2 overexpressing cells with a COX-2-selective inhibitor, NS-398 (10 microM), decreased PGE2 level and attenuated VEGF expression. Addition of PGE2 (10 microM) and the stable analog of PGI2, carbaprostacyclin (5 microM), to Hep3B cells also increased VEGF expression. Up-regulation of COX-2 correlates with VEGF expression and tumor angiogenesis in HBV-associated HCC. Moreover, COX-2 up-regulates VEGF expression in HCC cells, possibly via PGs production. Selective inhibition of COX-2 may block HCC associated angiogenesis and thus provides a rational approach for treatment of this malignancy.
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PMID:Cyclooxygenase-2 pathway correlates with vascular endothelial growth factor expression and tumor angiogenesis in hepatitis B virus-associated hepatocellular carcinoma. 1501 Aug 22

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