Viruses and cancer.

The fact that viruses can cause cancer in animals has been appreciated since the turn of the century. The widely held belief that viruses had little to do with cancer in humans has only recently been dispelled. Two classes of human retrovirus (HTLV and HIV) have been discovered in the last decade and the malignant potential of hepatitis B virus, Epstein Barr Virus and the human papilloma virus have been documented not only by confirming their association with disease by large scale epidemological studies but also at the molecular level. Indeed detailed investigation of the way viruses can cause cancer can reveal new insights into 'final common pathways' and hopefully provide new approaches for treatment over and above the real possibility that virus associated cancers can potentially be vaccinated against.