The possible etiological role of retroviruses in human tumors.

A short review of the data on retroviruses and human tumors from the past is given and discussed in comparison to some features of animal oncoviruses. The epidemiological association of a newly isolated retrovirus (HTLV/ATLV) with human adult T-cell lymphomas and the demonstration of onc-genes homologous to those of retroviruses in human cellular DNA has opened new aspects of the possible role of retroviruses in the etiology of human tumors.