Innsbruck – Cholesterol-lowering drugs widely used to prevent heart disease can also boost anti-cancer effect of interleukine-2 (IL-2) immune therapy. When added to tumour cell cultures treated with IL-2, statins dose-dependently co-activated specific Natural Killer cells (CD56dim NK cells) and induced tumour cell apoptosis. A team headed by Martin Thurner from Innsbruck University found that NK activation was mediated by two mechanisms (Cancer Res., doi: 10.1158/0008-5472.CAN-10-1968). First, inhibition of protein prenylation boosted production of caspase-1. Then statins induced production of the cytokines IL-18 and -1b, which are required for co-activation of NK cells. Until now, statins were believed to have a neutral effect on cancer growth (JAMA 295(1):74-80).