Liver Cancer in Transgenic Mice Carrying the Human Immunodeficiency Virus tat Gene1

Patients with the acquired immunodeficiency syndrome are at risk to develop a variety of different cancers. Based on epidemiolÃ3gica! data, Kaposi's sarcoma and non-Hodgkin's lymphoma have been clearly asso ciated with infection by the human immunodeficiency virus (HIV). Ad ditional cancers such as basal cell and squamous cell carcinomas, mela noma, and hepatocellular carcinoma have also been reported to be asso ciated with a diagnosis of acquired immunodeficiency syndrome. A direct causal role of HIV has yet to be established for any of these cancers. We now report that transgenic mice carrying the HIV tat gene develop a high incidence of hepatocellular carcinoma after a long latency and that these changes in the liver are likely to be initiated by extrahepatic growth signals from the tat expressing cells in these mice. We predict that as acquired immunodeficiency syndrome patients begin to respond to ther apy and show prolonged survival, such "secondary" malignancies induced by HIV will become increasingly prevalent.