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)

Suicide gene therapy combining herpes simplex virus thymidine kinase gene transfer and ganciclovir administration can be envisioned as a powerful therapeutical approach in the treatment of hepatocellular carcinoma; however, safety issues regarding transgene expression in parenchyma cells have to be addressed. In this study, we constructed LATKW, a lentiviral vector expressing the HSV-TkEGFP gene placed under the control of the promoter elements that control the expression of the rat alpha-fetoprotein, and assayed its specific expression in vitro in hepatocarcinoma and nonhepatocarcinoma human cell lines, and in epidermal growth factor stimulated human primary hepatocytes. Using LATKW, a strong expression of the transgene was found in transduced hepatocarcinoma cells compared to a very low expression in nonhepatocarcinoma human cell lines, as assessed by Northern blot, RT-PCR, FACS analysis and ganciclovir-mediated toxicity assay, and no expression was found in lentivirally transduced normal human hepatocytes. Altogether, these results demonstrate the possibility to use a lentivirally transduced expression unit containing the rat alpha-fetoprotein promoter to restrict the HSV-TK-mediated induced GCV sensitivity to human hepatocarcinoma cells.
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PMID:Hepatoma cell-specific ganciclovir-mediated toxicity of a lentivirally transduced HSV-TkEGFP fusion protein gene placed under the control of rat alpha-fetoprotein gene regulatory sequences. 1294 88

We examined the expression of the midkine (MK) and alpha-fetoprotein (AFP) genes in 15 paired human specimens obtained from hepatocellular carcinoma (HCC) and the corresponding noncancerous regions of the same patients. A total of 14 HCC but none of the noncancerous specimens were positive for the MK mRNA. In contrast, three HCC specimens and one corresponding noncancerous sample out of the three AFP-positive HCC cases expressed the AFP gene. A 2.3-kb genomic fragment in the regulatory region of the MK gene could activate a fused reporter gene in both AFP-producing and -nonproducing HCC lines, and the MK fragment-mediated transcriptional activity was comparable to the AFP enhancer-linked AFP promoter in AFP-producing cell lines. The AFP-producing but not AFP-nonproducing HCC cell lines that were transfected with the MK promoter-linked herpes simplex virus-thymidine kinase (HSV-TK) gene became susceptible to a prodrug ganciclovir to a similar degree of the HCC transfected with the enhancer-linked AFP promoter-fused HSV-TK gene. These data suggest that the MK promoter can activate a therapeutic gene preferentially in HCC and is as useful as the AFP promoter in clinical settings.
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PMID:A promoter region of the midkine gene that is frequently expressed in human hepatocellular carcinoma can activate a suicide gene as effectively as the alpha-fetoprotein promoter. 1296 30

The delivery of "suicide" herpes simplex virus type-1 thymidine kinase gene (tk) into tumor cells, followed by treatment with synthetic nucleotide analogues (gancyclovir, acyclovir), is a perspective approach to cancer therapy. Serious limitations in employment of the existing means of gene delivery into target cells constitute the main obstacle for cancer gene therapy development. In the present work a possibility to use a nonviral gene delivery system is shown based on the employment of lysine rich peptide K8 and amphipathic peptide JTS-1 for transferring tk gene into human hepatoma HepG2 cells. Cationic peptide K8 forms compact complexes with plasmid DNA, and JTS-1 acts as a pH-dependent endosomal releasing agent. Transfection of HepG2 cells by tk expression vector coupled with K8/JTS-1 peptides, followed by acyclovir administration (50-100 micrograms/ml) for 24 h leads to cell cycle arrest in the G1/S checkpoint of some cells, which eventually die through apoptosis. Treatment of HepG2 cells with higher acyclovir concentration (200 micrograms/ml) additionally results in a nonspecific toxic effect. The above results demonstrate the efficacy of K8/JTS-1 delivery system for the "suicide" cancer gene therapy, and may be regarded as a basis for further elaboration of "suicide" cancer approaches in vivo.
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PMID:[Delivery of "suicide" thymidine kinase gene of herpes virus in the complex with cationic peptide into human hepatoma cells in vitro]. 1469 55

Hepatocyte nuclear factor-4alpha (HNF-4alpha), the gene for the maturity-onset diabetes of the young type 1 (MODY1) form of type 2 diabetes mellitus (T2DM), is within the T2DM-linked region on chromosome 20q12-q13.1 and consequently, is a positional candidate gene for T2DM. Mutations in the coding region of HNF-4alpha are rare in diabetes affected subjects. Altered regulation of HNF-4alpha gene expression, controlled by distant enhancer sequences, may contribute to the development of type 2 diabetes. Comparative sequence analysis was performed between 13 kb of genomic DNA 5' to the P1 promoter sequences of the human, mouse, and rat HNF-4alpha coding sequences. Three regions, located at -10.5 kb (295 bp in length), -6.25 kb (421 bp in length), and -5.36 kb (263 bp in length), have significant sequence identity between the species. These three regions were functionally characterized using the chloramphenicol acetyltransferase (CAT) reporter assay, in which the conserved 5' regions of mouse HNF-4alpha were cloned in front of the herpes simplex virus thymidine kinase promoter driving transcription of the CAT gene. A fragment containing the 421 bp conserved region significantly increased CAT activity in differentiated rat hepatoma cells (13.7-+/-1.9-fold control), while only a modest increase in CAT activity was observed in pancreatic cells (2.5-+/-0.9-fold control; 1.6-+/-0.1-fold control) and dedifferentiated hepatoma cells (1.7-+/-0.4-fold control). The remaining two conserved regions increased CAT activity minimally in pancreatic (1.1-+/-0.1-fold control to 1.9-+/-0.1-fold control) and hepatic (1.6-+/-0.5-fold control to 2.3-+/-0.4-fold control) cell lines. Denaturing high-performance liquid chromatography (DHPLC) was used to search for sequence variants in DNA from 259 T2DM individuals. Two single nucleotide polymorphisms (SNPs) were identified, both of which increased CAT activity in the insulinoma cell lines in the CAT reporter assay (1.4-fold increase over wild-type; 1.7-fold increase over wild-type). These results suggest that comparative sequence analysis can efficiently identify regulatory elements and that sequence variants in regulatory elements of HNF-4alpha can contribute to altered HNF-4alpha gene expression.
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PMID:Comparative genomic analysis of the HNF-4alpha transcription factor gene. 1474 Nov 92

Tumor hypoxia induces vascular endothelial growth factor (VEGF) expression, which stimulates tumor angiogenesis. The VEGF pathway is inhibited by soluble VEGF receptors (soluble fetal liver kinase-1 [sFlk-1]) that bind VEGF and block its interaction with endothelial cells. Herpes simplex virus (HSV)-derived amplicons are replication-incompetent viruses used for gene delivery. We attempt to attenuate angiogenesis and inhibit hepatoma growth through amplicon-mediated expression of sFlk-1 under hypoxic control. A multimerized hypoxia-responsive enhancer (10xHRE) was cloned upstream of the sFlk-1 gene (10xHRE/sFlk-1). An amplicon expressing 10xHRE/sFlk-1 was genetically engineered (HSV10xHRE/sFlk-1). SK-HEP-1 human hepatoma cells were transduced with HSV10xHRE/sFlk-1 and incubated in normoxia (21% O2) or hypoxia (1% O2). Human umbilical vein endothelial cell assay evaluated capillary inhibition. Western blot assessed sFlk-1 expression. SK-HEP-1 flank tumors (n = 24) in athymic mice were treated with HSV10xHRE/sFlk-1. Media from hypoxic SK-HEP-1 transduced with HSV10xHRE/sFlk-1 yielded an 80% reduction in capillary formation (P < 0.005), whereas normoxic SK-HEP-1 yielded a 25% reduction (P < 0.05). Western blot of SK-HEP-1 transduced with HSV10xHRE/sFlk-1 demonstrated greater sFlk-1 expression in hypoxia vs. normoxia. SK-HEP-1 tumors treated with HSV10xHRE/sFlk-1 yielded a 72% reduction in volume vs. the control group (P < 0.000001). HSV amplicon-mediated delivery of a hypoxia-inducible soluble VEGF receptor substantially reduces new vessel formation and tumor growth in hepatoma.
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PMID:Herpes simplex virus amplicon delivery of a hypoxia-inducible angiogenic inhibitor blocks capillary formation in hepatocellular carcinoma. 1553 Dec 34

Congenital and neonatal viral infections usually display their acute manifestations in highly recognisable ways, for example, congenital rubella, cytomegalovirus (CMV), varicella, human immunodeficiency (HIV) and herpes simplex virus (HSV) infection. By contrast, congenital hepatitis B virus (HBV) infection may go undetected for years. Some of these are preventable, but what is not immediately apparent is that the long-term consequences are being prevented as well. The long-term consequences of congenital and neonatal infections include endocrine, immunological and cardiovascular disease, deafness, visual problems, intellectual handicap and cerebral palsy. With the survival of HIV-infected infants into adulthood the long-term consequences will soon be described. Maternally and neonatally transmitted HBV infection predisposes to carriage, liver cirrhosis and hepatocellular carcinoma in young adults. Neonatal HBV vaccination prevents adult cancer. Acquired viral infections may predispose to subsequent lung disease, malabsorption, fertility problems or neurological disability. In the prevention of acquired rubella, varicella, HBV, influenza, poliovirus, measles and hepatitis A, one should mention the added bonus of preventing secondary cases by preventing transmission from infants and children to other children and adults. Preventing paediatric HSV, HBV and HIV infection in females may even be preventing subsequent transmission to future generations. Turning to paediatric bacterial infections, vaccinating infants and young children against pertussis could not only prevent transmission to older children and adults but also break the cycle, which then transmits from adults back to infants and young children. There is evidence that disease in older age groups, including adults, has been prevented by virtue of herd immunity from paediatric vaccination, e.g. Neisseria meningitidis Group C and Streptococcus pneumoniae. The add-on benefits for other generations, including for adults, arising from the prevention of paediatric infections are considerable.
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PMID:Paediatric infections: prevention of transmission and disease--implications for adults. 1575 76

The promoter region of the early-growth response-1(Egr-1) gene has been shown to be activated by external radiation, thus making a selective tumoricidal effect possible. A previous experiment showed that the Egr-1 promoter can be activated by internal radiation using radioisotopes as well as external radiation. Internal radiation using I-131 lipiodol (I-131-Lip) has been established as one of the most useful therapeutic strategies against hepatoma. We herein linked the Egr-1 promoter to the herpes simplex virus-thymidine kinase (HSV-TK) gene, and investigated its efficacy in hepatoma gene therapy in combination with I-131-Lip. A luciferase assay showed the Egr-1-promoter activity to be markedly increased in hepatoma tissue specimens in an I-131-dose-dependent manner, whereas a less than two-fold increase in this activity was observed in other organs. In addition, the radioactivity derived from I-131 was selectively accumulated in the tumor tissue specimens. To examine the efficacy of EgrTK/ganciclovir (GCV) gene therapy in vivo, subcutaneous hepatoma xenografts in nude mice were transfected using a hemagglutinating virus of Japan (HVJ)-liposome vector. Complete tumor regression was observed in all the EgrTK-transfected tumors following combination treatment with I-131-Lip and GCV 42 days after treatment without any side effects (n=8). In contrast, the tumors continued to grow in all control mice (n=10). Furthermore, the serum alpha-fetoprotein levels decreased in the combination therapy group, while they increased in the controls. In conclusion, these data indicate that Egr-1 promoter-based gene therapy combined with internal radiation has a selective effect on hepatoma tumors while also showing an improved in vivo efficacy. This combination therapy might, therefore, be an effective human hepatoma gene therapy, even in advanced multiple cases.
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PMID:Eradication of hepatocellular carcinoma xenografts by radiolabelled, lipiodol-inducible gene therapy. 1607 87

Sleeping Beauty (SB) is a gene-insertion system reconstructed from transposon sequences found in teleost fish and is capable of mediating the transposition of DNA sequences from transfected plasmids into the chromosomes of vertebrate cell populations. The SB system consists of a transposon, made up of a gene of interest flanked by transposon inverted repeats, and a source of transposase. Here we carried out a series of studies to further characterize SB-mediated transposition as a tool for gene transfer to chromosomes and ultimately for human gene therapy. Transfection of mouse 3T3 cells, HeLa cells, and human A549 lung carcinoma cells with a transposon containing the neomycin phosphotransferase (NEO) gene resulted in a several-fold increase in drug-resistant colony formation when co-transfected with a plasmid expressing the SB transposase. A transposon containing a methotrexate-resistant dihydrofolate reductase gene was also found to confer an increased frequency of methotrexate-resistant colony formation when co-transfected with SB transposase-encoding plasmid. A plasmid containing a herpes simplex virus thymidine kinase gene as well as a transposon containing a NEO gene was used for counterselection against random recombinants (NEO+TK+) in medium containing G418 plus ganciclovir. Effective counterselection required a recovery period of 5 days after transfection before shifting into medium containing ganciclovir to allow time for transiently expressed thymidine kinase activity to subside in cells not stably transfected. Southern analysis of clonal isolates indicated a shift from random recombination events toward transposition events when clones were isolated in medium containing ganciclovir as well as G418. We found that including both transposon and transposase functions on the same plasmid substantially increased the stable gene transfer frequency in Huh7 human hepatoma cells. The results from these experiments contribute technical and conceptual insight into the process of transposition in mammalian cells, and into the optimal provision of transposon and transposase functions that may be applicable to gene therapy studies.
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PMID:Counterselection and co-delivery of transposon and transposase functions for Sleeping Beauty-mediated transposition in cultured mammalian cells. 1615 96

Cell-specific, replicating viruses are being developed as a new class of oncolytic agents. A novel approach to viral gene therapy with the use of replication-competent herpes simplex virus has been described; G92A is a replication-competent, multimutant oncolytic herpes simplex virus (HSV) that has been evaluated for anticancer effects and selectivity in the treatment of subcutaneous tumors. G92A replicates efficiently in albumin-producing tumor cell lines but not in non-albumin-producing tumor cell lines, whereas both types are equally susceptible to a non-tissue-specific recombinant HSV, hrR3. In this study, we analyzed the antitumoral efficacy of a single intrasplenic G92A or hrR3 injection in nude mice. In vivo, G92A replicated well in liver xenografts of human albumin-producing hepatoma cells (Hep3B) but not in liver xenografts of a non-albumin-producing malignant colon tumor cell line (HT29), whereas hrR3 replicated well in both tumor types. G92A effectively and selectively replicated throughout liver tumors without apparent hepatotoxicity and inhibited tumor growth, leading to a significantly increased survival time. By monitoring lacZ histochemical staining, we determined the oncolytic potential of recombinant HSV against liver tumors. Our results indicate that G92A warrants further investigation as a clinical therapy against malignant liver tumors.
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PMID:Oncolytic recombinant herpes simplex virus for treatment of orthotopic liver tumors in nude mice. 1652 26

The rising incidence of hepatocellular carcinoma (HCC) in western countries, along with the poor prognosis offered by present-day treatment modalities, makes novel therapies for this disease necessary. Oncolytic herpes simplex viruses (HSV) are replication-competent viruses that are highly effective in the treatment of a wide variety of experimental models of human malignancies. This study seeks to investigate the effectiveness of oncolytic herpes viruses in the treatment of primary HCC cell lines. Sixteen commercially available human HCC cell lines were studied. G207 is an attenuated, replication-competent, oncolytic HSV engineered to selectively replicate within cancer cells. Cell lines were tested for viral sensitivity to G207 and their ability to support viral replication using standard cytotoxicity and viral replication assays. Eleven of 16 cell lines were moderately to highly sensitive to G207 viral oncolysis. HCC cell lines additionally demonstrated the ability to support viral replication in vitro with as high as 800-fold amplification of the administered viral dose observed. G207 is cytotoxic to, and efficiently replicates within, HCC cell lines in vitro. From these data, we suggest that oncolytic HSV therapy may have a role in the treatment of HCC, and in vivo studies are warranted.
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PMID:Oncolytic herpes viral therapy is effective in the treatment of hepatocellular carcinoma cell lines. 1662 19


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