Proposed model for the antitumoral activity of Ocimum gratissimum extracts on the human lung adenocarcinoma A549. Our data demonstrated that Ocimum gratissimum extract induces activation of caspase-3, caspase-9, and caspase-8, which may attribute to the increase of Apaf-1 and Bak, the decrease of antiapoptotic Bcl-2, as well as the inhibition of ERK1/2 survival signaling and the enhancement of JNK and p38 stress signal cascades.