Although the incidence of AIDS-associated non-Hodgkin's lymphoma (AIDS- NHL) continues to increase as the AIDS epidemic progresses, the incidence of T-cell associated AIDS-NHL has only sporadically been reported. At San Francisco General Hospital, an increase in T-cell AIDS-NHL has recently been seen, and in preliminary studies, we found HIV clonally integrated into the DNA of three out of four CD4-expressing monoclonal T-cell AIDS- NHL analyzed. In two cases analyzed in depth, HIV was found integrated with the fur gene, located immediately 5' to the c-fes/fps protooncogene. As a part of Phases I and II of this proposal, the project will focus on analyzing the HIV's involved in T-cell AIDS-NHL to determine whether: a) mutant HIV's capable of causing rapid cellular transformation have evolved; c-fes/fps expression is modulated by HIV in the first two cases analyzed and determine the HIV genes critical for inducing the transformed phenotype in association with c-fes/fps.