[Molecular biological aspects of oncogenesis caused by RNA tumor viruses (author's transl)]

This article concerns the molecular mechanisms by which RNA tumor viruses, commonly called as oncornaviruses, transfer their genetic information from the genomic RNA (70 s RNA) of the virions to the cellular DNA, leading to neoplastic transformations. The article describes biochemical and serological properties of reverse transcriptase, its role in the life cycle of RNA tumor viruses and broader implications to molecular biology. In this connection, the authors report their own findings on the role of reverse transcriptase in a preleukemic disease, myelofibrosis. This enzyme, discovered in their laboratory, is antigenically closely related to reverse transcriptase of certain primate RNA tumor viruses, and of human leukemic cells. The article also describes the role of reverse transcriptase inhibitors in viral oncogenesis. Of particular interest, is the partially thiolated polycytidylic acid (MPC) which has been developed by the authors, and is known to have a very high binding affinity to the viral reverse transcriptase. The implication of these basic data on the clinical effectivity of MPC in human leukemia, documented in a few cases, has been discussed.