Antisense RNA directed to the human papillomavirus type 16 E7 mRNA from herpes simplex virus type 1 derived vectors is expressed in CaSki cells and downregulates E7 mRNA.
BACKGROUND
Human papillomavirus (HPV) infection is known to be the most important etiologic factor of cervical cancer. There is no HPV specific therapy available for treatment of invasive squamous cell carcinoma of the cervix and its precursor lesions. The present study elucidates the potential to use herpes simplex virus (HSV) derived vectors for expression of antisense RNA to HPV -16 E7 oncogene.


RESULTS
We have constructed replication competent, nonneuroinvasive HSV-1 vectors, deleted of the gamma134.5 gene. The vectors express RNA antisense to the first 100 nucleotides of the HPV-16 E7 gene. We assayed the ability of the antisense E7 vectors R5225 (tk-) and R5226 (tk+), to produce antisense RNA, as well as the consequent effects on E7 mRNA and protein levels in HPV-16 positive CaSki cells. Anti-E7 RNA was expressed by both constructs in a dose-dependent manner. Expression of HPV-16 E7 mRNA was downregulated effectively in CaSki cells infected with the tk- recombinant R5225 or with R5226. The tk+ recombinant R5226 was effective in downregulating E7 protein expression.


CONCLUSIONS
We have shown that anti-E7 RNA expressed from an HSV vector could efficiently downregulate HPV-16 E7 mRNA and E7 protein expression in CaSki cells. We conclude that HSV vectors may become a useful tool for gene therapy of HPV infections.
Kari
Ilkka
I
Department of Virology, Institute of Dentistry, University of Turku, Turku, Finland. ilanka@utu.fi
Syrjänen
Stina
S
Johansson
Bo
B
Peri
Piritta
P
He
Bin
B
Roizman
Bernard
B
Hukkanen
Veijo
V
D000998:Antiviral Agents / Q000494:pharmacology; D045744:Cell Line, Tumor; D015536:Down-Regulation; D015870:Gene Expression / Q000187:drug effects*; D015967:Gene Expression Regulation, Viral; D005822:Genetic Vectors / Q000235:genetics; D018259:Herpesvirus 1, Human / Q000235:genetics*; D052162:Human papillomavirus 16 / Q000235:genetics*; D006801:Humans; D009856:Oncogene Proteins, Viral / Q000096:biosynthesis / Q000235:genetics*; D050725:Papillomavirus E7 Proteins; D016372:RNA, Antisense / Q000096:biosynthesis / Q000235:genetics / Q000494:pharmacology*; D012333:RNA, Messenger / Q000037:antagonists & inhibitors* / Q000096:biosynthesis; D012367:RNA, Viral / Q000037:antagonists & inhibitors* / Q000096:biosynthesis
D000998:Antiviral Agents; D009856:Oncogene Proteins, Viral; D050725:Papillomavirus E7 Proteins; D016372:RNA, Antisense; D012333:RNA, Messenger; D012367:RNA, Viral; C059731:oncogene protein E7, Human papillomavirus type 16