title: Analysis of human papillomavirus E7 protein status in C-33A cervical cancer cells.
abstract: High-risk human papillomaviruses (HPV) are the main etiologic factor for the development of cervical cancer. Infections by these viruses have been detected in virtually all cervical cancers. C-33A is one of the rare cervical cancer derived cell lines considered as HPV-negative. Employing monoclonal antibodies raised against a conformational epitope of the HPV-16 E7 oncoprotein, we present evidence suggesting that E7-positive cells can be sporadically and transiently detected in C-33A cell cultures. Immunoblotting with affinity-purified rabbit polyclonal anti-HPV 16 E7 antisera and q-RT-PCR analysis suggest that these cells do probably not express HPV-16 E7. Moreover, we show that the HPV E7 protein level differs considerably between individual cells in cultures of several established cervical cancer cell lines. Our data suggest that expression of the E7 protein is variable in established cervical cancer cell lines including C-33A cells.
authors.affiliation: Division of Cell Metabolism and Differentiation Research, Institute for Biomedical Aging Research, Universität Innsbruck, Rennweg 10, 6020, Innsbruck, Austria.
authors.forename: Andreas
authors.initials: A
authors.lastname: Kaiser
authors.forename: Brigitte
authors.initials: B
authors.lastname: Jenewein
authors.forename: Haymo
authors.initials: H
authors.lastname: Pircher
authors.forename: Ursula
authors.initials: U
authors.lastname: Rostek
authors.forename: Pidder
authors.initials: P
authors.lastname: Jansen-Dürr
authors.forename: Werner
authors.initials: W
authors.lastname: Zwerschke
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology; D000914:Antibodies, Viral / Q000276:immunology; D045744:Cell Line, Tumor; D004279:DNA, Viral / Q000032:analysis* / Q000235:genetics; D005260:Female; D052162:Human papillomavirus 16 / Q000737:chemistry* / Q000235:genetics* / Q000276:immunology; D006801:Humans; D015151:Immunoblotting; D050725:Papillomavirus E7 Proteins / Q000032:analysis* / Q000276:immunology; D060888:Real-Time Polymerase Chain Reaction; D002583:Uterine Cervical Neoplasms / Q000473:pathology*
chemical_list: D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral; D004279:DNA, Viral; D050725:Papillomavirus E7 Proteins