Adenovirus-mediated transfer of human papillomavirus 16 E6/E7 antisense RNA and induction of apoptosis in cervical cancer.
OBJECTIVE
In most cervical cancers, human papillomaviruses (HPVs) are identified. The E6 and E7 genes of HPVs encode proteins, that interfere with the function of the tumor suppressor proteins p53 and Rb. We are exploring the potential use of antisense HPV RNA transcripts for gene therapy for HPV-positive cervical cancers.


METHODS
Via a recombinant adenoviral vector, Ad5CMV-HPV 16 AS, we introduced the antisense RNA transcripts of the E6 and E7 genes of HPV type 16 into human cervical cancer SiHa cells harboring HPV 16. We then analyzed the effects of expression of these genes on cell and tumor growth.


RESULTS
HPV 16 E6/E7 antisense RNA was detected for 14 days in Ad5CMV-HPV 16 AS-infected cells. After infection, E6 and E7 protein expression was suppressed, and p53 and Rb protein expression increased. The Ad5CMV-HPV 16 AS-infected cells underwent apoptosis in vitro and in vivo. Cell growth and tumorigenicity were greatly suppressed. Ad5CMV-HPV 16 AS treatment significantly reduced the volumes of established subcutaneous tumors.


CONCLUSIONS
Transfection of cervical cancer cells with HPV 16 E6/E7 antisense RNA in a form such as Ad5CMV-HPV 16 AS might be a potentially useful approach to the therapy of HPV 16-positive cervical cancer.
Hamada
Katsuyuki
K
Department of Obstetrics and Gynecology, School of Medicine, Ehime University, Shitsukawa, Toon, Ehime 791-0295, Japan. hamakatu@m.ehime-u.ac.jp
Shirakawa
Toshiro
T
Gotoh
Akinobu
A
Roth
Jack A
JA
Follen
Michele
M
D000256:Adenoviridae / Q000235:genetics*; D017209:Apoptosis; D005260:Female; D005434:Flow Cytometry; D005822:Genetic Vectors / Q000235:genetics; D006801:Humans; D020287:In Situ Nick-End Labeling; D009856:Oncogene Proteins, Viral / Q000235:genetics*; D027383:Papillomaviridae / Q000235:genetics*; D050725:Papillomavirus E7 Proteins; D016372:RNA, Antisense / Q000235:genetics* / Q000627:therapeutic use; D012097:Repressor Proteins / Q000235:genetics; D014162:Transfection / Q000379:methods; D014407:Tumor Cells, Cultured; D002583:Uterine Cervical Neoplasms / Q000628:therapy* / Q000821:virology
C068651:E6 protein, Human papillomavirus type 16; D009856:Oncogene Proteins, Viral; D050725:Papillomavirus E7 Proteins; D016372:RNA, Antisense; D012097:Repressor Proteins; C059731:oncogene protein E7, Human papillomavirus type 16