Antiretroviral protease inhibitors have been shown to cause hyperlipidemia, raising concerns for the possibility of cardiovascular complications among HIV-infected patients. Statins have been successfully used in the management of hypercholesterolemia and were shown to exert antitumor effects. We report here that lovastatin and saquinavir exert cytostatic/cytotoxic effects against Daudi and Raji human lymphoma cells. Importantly, lovastatin potentiates the antitumor effects of saquinavir against these lymphomas in an additive manner. Addition of statins to antiretroviral treatment might therefore decrease some of its side effects while potentiating the antitumor effectiveness.