RNA interference for treating cancers caused by viral infection.

The newly discovered phenomenon of RNA interference (RNAi) offers the dual facility of selective viral gene silencing coupled with ease of tailoring to meet genetic variation within the viral genome. Such promise identifies RNAi as an exciting new approach to treat viral-induced diseases, including viral-induced cancers (e.g. cervical carcinoma, hepatocellular carcinomas and haematopoietic and lymphoid malignancies). Cervical cancer is the second most common cancer in women worldwide and is caused by human papilloma virus (HPV). Silencing of HPV gene expression by RNAi induces apoptosis of cervical carcinoma cells in culture, and the effect is apparent within 3 days. The RNAi process is triggered by double-stranded RNA (dsRNA), and a single dose is sufficient to maintain RNAi for several days in vitro (cell culture) and in vivo (experimental animal models). Thus, the stage is set for the development of novel antiviral and anticancer therapies based upon selective gene silencing by RNA interference.