Suppression of serum starvation-induced apoptosis by hepatitis C virus core protein

Hepatitis C virus (HCV) core protein either enhances or inhibits apoptosisdepending on the apoptosis-inducing stimuli and cell conditions. In this paper westudied possible effect of HCV core protein on apoptosis induced by serum starvation.NIH3T3 cells stably expressing HCV core protein were more resistant to serumstarvation-induced apoptosis than were the non-expressing control. Neither p53,p21Wafl nor Bax was detectably induced after serum starvation, irrespective of HCVcore protein expression, suggesting that the observed apoptosis is p53-independent.Serum starvation-induced apoptosis was partially inhibited by SB203580, a specificinhibitor of p38 mitogen-activated protein (MAP) kinase, in the non-expressingcontrol, but not in HCV core protein-expressing cells. Moreover, activation of p38MAP kinase after serum starvation, as measured by the amount of its phosphorylatedform, was inhibited in HCV core protein-expressing cells. Our results suggest thatHCV core protein inhibits serum starvation-induced apoptosis through inhibition ofp38 MAP kinase activation