Elevation of cyclin B1, active cdc2, and HuR in cervical neoplasia with human papillomavirus type 18 infection.
Over 30 cervical epitheliotrophic HPV types may lead to altered biological functions that affect the clinical outcome of HPV infection. In order to determine the regulatory mechanism and effect of different HPV subtypes, we performed functional assays on cdc2, cyclinB1 and HuR in human uterine cervical samples. After confirming 22 HPV types among 95 cervical swabs, 10 cervical tissues, and seven established cell lines using a DNA chip, we evaluated the functional activities of G2 molecules assays, that included; western blotting for cyclin B1, cdc2 and phospho-cdc2 (Y15 and T161), immunoprecipitation for cdc2, a nuclear extraction fractional assay, and RT-PCR for cyclin B1. The expression of cyclin B1 was found to be dependent on HPV type, and was particularly overexpressed in high-risk types, whereas cdc2 was ubiquitously expressed irrespective of HPV type. Phospho-cdc2 and cyclin B1, however, were most intense in HPV18 infected cervical samples. Furthermore, the HuR stabilizing factor of the cyclin B1 transcript was upregulated in HPV 18 infected swabs. Moreover, SiHa cell line showed weaker G2 functional activity than the HeLa cell line. This study demonstrates that HPV-18 decreases the fidelity of mitotic checkpoints and increases cdc2-associated histone H1 kinase activity relative to control populations, and further shows that the G2 checkpoint is aberrant by virtue of the stabilization of cyclin B1 mRNA through the upregulation of HuR protein and the functional form of cdc2, especially in cases with HPV 18 infected cervical lesions.
Cho
Nam Hoon
NH
Department of Pathology, Yonsei University College of Medicine, Seodaemoon-ku, Shinchon-dong 134, Seoul 120-752, South Korea. cho1988@yumc.yonsei.ac.kr
Kang
Suki
S
Hong
Sunghee
S
An
Hee Jung
HJ
Choi
Young Hyun
YH
Jeong
Goo Bo
GB
Choi
Heung Kuk
HK
D000954:Antigens, Surface / Q000032:analysis*; D016203:CDC2 Protein Kinase / Q000032:analysis*; D019926:Cyclin B / Q000032:analysis* / Q000235:genetics; D056744:Cyclin B1; D051959:ELAV Proteins; D000067780:ELAV-Like Protein 1; D005260:Female; D052161:Human papillomavirus 18; D006801:Humans; D030361:Papillomavirus Infections / Q000378:metabolism*; D010766:Phosphorylation; D012333:RNA, Messenger / Q000032:analysis; D016601:RNA-Binding Proteins / Q000032:analysis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016159:Tumor Suppressor Protein p53 / Q000502:physiology; D002583:Uterine Cervical Neoplasms / Q000737:chemistry*
D000954:Antigens, Surface; C534699:CCNB1 protein, human; D019926:Cyclin B; D056744:Cyclin B1; D051959:ELAV Proteins; D000067780:ELAV-Like Protein 1; C098770:ELAVL1 protein, human; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D016159:Tumor Suppressor Protein p53; D016203:CDC2 Protein Kinase