Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0019163 (hepatitis B)
 38,309 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Gene/biotechnology products can be either physiological peptides for the purpose of substitution of deficiencies or for therapeutic purposes in superphysiological concentrations, or nonphysiological peptides, or newer biotechnology products like monoclonal antibodies. The rules for clinical trials developed so far are also valid for clinical trials with gene/biotechnology products. Nevertheless, a major challenge for the clinical pharmacologist is the species specificity of many reactions induced by gene/biotechnology products in man. In general, animal experiments may be less predictive, so there is a greater demand for human pharmacology studies. Gene/biotechnology products offer more chances for treatment of many diseases, but during the clinical trials the clinician has to always be aware of unexpected side effects. Several newer gene technology products offer superior safety as compared to older biological products like Factor VIII preparations and human growth hormone. More than 19 therapeutics produced by gene/biotechnology have already been approved by health authorities all over the world. Major clinical benefit could be shown with hepatitis B vaccine, insulin, human growth hormone, TPA, erythropoietin, GM-CSF, G-CSF, and monoclonal antibodies for immune suppression. There is also good evidence of efficacy of interferon alpha in chronic hepatitis. So far, our knowledge about cytokines is still limited. In several cancer diseases, interferons show efficacy as well as in several autoimmune diseases. Well designed clinical pharmacology studies will be important to elaborate the therapeutic potential of drugs arising from gene/biotechnology.
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PMID:Clinical trials of gene/biotechnology products. 788 81

Human hepatitis B virus (HBV) X protein, HBx, transactivates virus and host genes through a wide variety of cis-elements. Expression of HBx is controlled by HBV enhancer 1 (Enh1). Both Enh1 and the core sequence of Enh1, which consists of an AP-1 related site (cFAP1) and a C stretch, respond to HBx and a phorbol ester (TPA). Biochemical pathways of the responses to HBx and TPA are still controversial. We therefore asked whether HBx and TPA stimulate Enh1 core activity through a common process. Protein kinase C (PKC) inhibitors, H-7 and staurosporin, did not inhibit HBx transactivation at concentrations sufficient to abolish the TPA effects in HepG2 cells. Although HBx transactivation synergized independently with TPA or a phosphoprotein phosphatase inhibitor, okadaic acid (OA), the PKC inhibitors eliminated only the TPA contribution. HBx transactivation required both the cFAP1 and the C stretch of the Enh1 core region; however, mutations in either or both of the two cis-elements demonstrated that TPA augmentation required only cFAP1. These results imply that HBx transactivation operates through a mechanism distinct from the PKC and OA activation pathways.
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PMID:Transactivation of human hepatitis B virus X protein, HBx, operates through a mechanism distinct from protein kinase C and okadaic acid activation pathways. 811 51

The hepatitis B virus (HBV) X protein (pX) stimulates transcription regulated by cis-acting elements that control many viral and cellular genes, including the c-myc and the c-fos proto-oncogenes. Using several c-fos promoter deletion mutants, we found the serum-responsive element (SRE) located at -315, the modified TPA-responsive element located at -296 (fos-AP-1 binding site, FAP) and the region spanning from nucleotide -220 to -120, which contains an NF1-like site and several stretches of sequence homologous to the AP-2 consensus binding sites, to be responsive to pX. pX does not modify the pattern of the retarded complexes bound to the SRE/FAP region which, in our system, appears to be occupied by SRE-binding factors. The activation of the SRE does not involve complex formation between SRE-binding factors and pX, it is not associated with an increase in serum response factor binding to the SRE and it does not determine changes in SRE mobility-shift pattern.
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PMID:The hepatitis B virus (HBV) pX transactivates the c-fos promoter through multiple cis-acting elements. 850 80

Insulin suppresses hepatitis B surface antigen (HBsAg) gene expression and stimulates cell proliferation in human hepatoma Hep3B cells. 12-O-tetradecanoyl phorbol-13-acetate, TPA, has been demonstrated to mimic insulin actions in these cells. We examined the role of phosphatidylinositol 3-kinase (PI 3-kinase) in the signaling pathways of insulin and TPA towards these two biological phenomena in Hep3B cells. The pre-treatment of 5 microM of wortmannin diminished insulin suppressed HBsAg production and completely abolished insulin stimulated cell proliferation. However, wortmannin had no effect on TPA actions in both HBsAg suppression and cell growth stimulation. We further investigated the effect of wortmannin in mitogen-activated protein kinases (MAPKs) activation induced by insulin or TPA. After the pretreatment of wortmannin, insulin activated MAPKs was completely blocked, but TPA was still capable to activate MAPKs. These results suggest that PI 3-kinase is involved in insulin actions but not in TPA effects, and allow us to dissociate the signaling pathways of insulin and TPA in human hepatoma Hep3B cells.
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PMID:Phosphatidylinositol 3-kinase is required for the regulation of hepatitis B surface antigen production and mitogen-activated protein kinase activation by insulin but not by TPA. 960 88