RNA interference: a potential tool against Kaposi's sarcoma-associated herpesvirus.
OBJECTIVE
RNA interference is a conserved cellular function that controls viral infection, the expression of transposable elements, repetitive sequences and genes in embryonic development. Originally described as an antiviral mechanism in plants, known as posttranscriptional gene silencing, it is now appreciated that this phenomenon occurs in all living cells. Double-stranded RNA, when acting as part of RNA interference, reduces expression of genes with sequence similarity, but has no effect on the expression of genes of unrelated sequence. Studies of RNA interference in mammalian cells have demonstrated that exogenous genes delivered by DNA transfection as well as endogenous gene expression can be suppressed by the delivery of RNA interference. We discuss here the potential for exploiting this phenomenon to prevent or treat viral infections, in particular Kaposi's sarcoma-associated herpesvirus.


RESULTS
There have been several studies showing that RNA interference can be exploited to target a wide range of human viruses, including HIV-1, human T cell leukaemia virus-1, human papillomavirus, hepatitis B, hepatitis C and the polio virus. RNA interference is effective in mammalian cells and can be delivered by various methods. Double-stranded RNA has been injected into the tail veins of mice to block both virally and chemically induced hepatitis.


CONCLUSIONS
A greater understanding of RNA interference allows us to exploit this phenomenon in order to study the functions of genes in mammalian cells, and also to target the expression of mutated cellular or viral genes. New delivery techniques should be developed to allow the process to be used as a therapeutic tool against viruses and malignancies in humans.
Godfrey
Andrew
A
Cancer Research UK Viral Oncology Group, Wolfson Institute for Biomedical Research, University College London, London, UK.
Laman
Heike
H
Boshoff
Chris
C
D023241:Antiretroviral Therapy, Highly Active; D006566:Herpesviridae Infections / Q000628:therapy*; D019288:Herpesvirus 8, Human / Q000235:genetics*; D006801:Humans; D034622:RNA Interference; D012514:Sarcoma, Kaposi / Q000628:therapy*