Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: DrugBank:EXPT01586 (G418)
 2,237 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The oncogenic potential of human papillomavirus type 18 which is found in a significant number of cervical and penile cancer biopsies was tested in primary human keratinocytes derived from neonatal foreskin. Viral DNA and a gene for resistance to neomycin were introduced into these cells by calcium phosphate transfection. Selection of cells in G418 led to the isolation of resistant colonies which were propagated in culture. Four cell lines termed FE-A, FEH 18L, FEP18-5, and FEP18-11 have been maintained in culture for 1 1/2-2 years and were selected for further analysis. In all cases the viral DNA was integrated into the cellular genome and the early genes were transcribed, including RNA complementary to the E2, E6, and E7 open reading frames. Radioimmunoprecipitation showed that all cell lines synthesized the E6 and E7 proteins. However, none of the cell lines tested were tumorigenic. The differentiation capacity of these cells was analyzed by assessing their ability to proliferate clonally after exposure to 1.2 mM calcium chloride. All four cell lines were resistant to this stimulus and formed colonies upon return to regular growth medium whereas normal cells differentiated terminally. K6a and K14 keratin RNA expression was down-regulated in the HPV immortalized cell lines compared to primary human epithelial cells.
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PMID:HPV-18 immortalization of human keratinocytes. 247 70

HaCaT cells, a spontaneously immortalised, nontumorigenic keratinocyte line, were used as a more amenable model than primary keratinocytes for ex vivo-mediated gene transfer. These cells were transduced with retroviral vectors containing the factor IX cDNA under the control of a cytomegaloviral (CMV) promoter/enhancer alone or as hybrids with either the human papilloma virus-16 (HPV-16), keratin 14 (hK14) or keratin 5 (hK5) regulatory elements. Unlike primary keratinocytes, HaCaT cells tolerated transduction and G418 selection well. The HPV-16 and hK5 hybrid constructs were disproportionately more active in primary keratinocytes than in the basal-like HaCaT cells. After skin grafting to athymic mice, transduced HaCaT cells differentiated to form a stratified epidermis that remained viable for at least 99 days in some mice. Factor IX in plasma of mice grafted with vectors containing the HPV-16 and hK5 elements was two- to three-fold higher than with vectors containing the CMV promoter alone. These results are consistent with the expected up-regulation in differentiated suprabasal cells by the HPV-16 and hK5 elements. Enhancers may be useful in specifically targeting the differentiated layer of the epidermis or achieving higher levels of gene expression after transplantation.
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PMID:Differentiation-specific enhancer activity in transduced keratinocytes: a model for epidermal gene therapy. 961 60