Repression of HPV E6-activated RSV promoter activity by anti-cancer agents.
Human papillomavirus E6 forms a complex with p53 tumor suppressor and E6-associated protein, leading to the degradation of p53 via the ubiquitination pathway, resulting in the oncogenesis of cervical carcinomas. Several viral and cellular gene promoters were shown to be transactivated by E6 oncogene. In this study, to understand the role of transcription activity of E6 related to cervical carcinogenesis, the effect of cervical cancer drugs on E6 induced transcription activity has been elucidated. Several viral promoter (RSV, CMV, SV40, and HIV)-luciferase reporter gene constructs, and eukaryotic E6 expression vector were prepared as an E6 transcription analysis system and an exogenous E6 protein source, respectively. It was shown that the promoters of RSV, SV40, and HIV, but not CMV, were transactivated by HPV 16 E6 in cervical cancer cell line. Several known cervical cancer drugs were investigated for their effects on transcription activity of E6 in SiHa stably transfected with E6-responsive promoters. Cervical cancer drugs consistently reduced luciferase activity, in transfectants with RSV-luc (SiHa/pRSV-luc, KCTC 0427BP) E6 mRNA also. Thus, in this study, we have demonstrated that the promoters of RSV, HIV, and SV40 were transactivated by E6 in cervical cancer cells. Three cervical cancer drugs downregulated RSV-luc transcription and E6 expression by a p53 independent pathway. RSV-luc promoter analysis system could be useful for understanding the role of transcription activity of E6 related to cervical cancer and also for screening drugs against cervical cancers caused by HPV infection.
Kang
Yun Hee
YH
Cellular Biology Laboratory, Korea Research Institute of Bioscience and Biotechnology, Taejon 305-600, South Korea.
Kang
Man-Jong
MJ
Paik
Sang Gi
SG
Park
Sue Nie
SN
Yoon
Do-Young
DY
D000970:Antineoplastic Agents / Q000494:pharmacology*; D003588:Cytopathogenic Effect, Viral / Q000187:drug effects; D015536:Down-Regulation; D005260:Female; D005822:Genetic Vectors / Q000235:genetics; D006801:Humans; D009856:Oncogene Proteins, Viral / Q000096:biosynthesis / Q000235:genetics*; D027383:Papillomaviridae / Q000187:drug effects / Q000235:genetics*; D030361:Papillomavirus Infections / Q000188:drug therapy; D011401:Promoter Regions, Genetic / Q000187:drug effects*; D012367:RNA, Viral / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins; D012136:Respiratory Syncytial Viruses / Q000235:genetics*; D015533:Transcriptional Activation / Q000187:drug effects / Q000235:genetics; D014162:Transfection; D014407:Tumor Cells, Cultured; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D014412:Tumor Virus Infections / Q000188:drug therapy; D002583:Uterine Cervical Neoplasms / Q000821:virology; D014764:Viral Proteins / Q000096:biosynthesis / Q000235:genetics
D000970:Antineoplastic Agents; C068651:E6 protein, Human papillomavirus type 16; D009856:Oncogene Proteins, Viral; D012367:RNA, Viral; D012097:Repressor Proteins; D016159:Tumor Suppressor Protein p53; D014764:Viral Proteins