Human tumor viruses

Tumor viruses play an important role for the development of a substantial f raction of human malignancies, including common cancers, such as carcinomas of the cervix uteri, hepatocellular carcinomas, or lymphomas. In the recen t past, much progress has been made in elucidating the molecular mechanisms by which human tumor viruses contribute to cellular growth deregulation an d carcinogenesis. The picture emerges that different tumor viruses target s imilar cellular pathways for growth deregulation but, in addition, also hav e unique properties contributing to oncogenesis. Malignant transformation t ypically requires additional genetic alterations of the host cell, to which tumor viruses can contribute by destabilizating the cellular genome.