Differential DRAK2 expression was confirmed by quantitative RT-PCR (qRT-PCR) on template from HCA7 cells. Induction of DRAK2 expression was observed as early as 4 h after treatment with SC236 and was inhibited by co-administration of PGE 2 ( Figure 2B) . A 4.4-fold induction of DRAK2 expression (relative to control) was observed with SC236 (5 mM) after 4 h (P ¼ 0.001), a response that was attenuated on co-incubation with prostaglandin (SC236 vs SC236 þ PGE 2 , P ¼ 0.01), suggesting that the changes in DRAK2 expression were dependant on variations in prostaglandin generation. Indirect immunofluorescent staining for DRAK2 in HCA7 cells showed a corresponding increase in levels of DRAK2 protein with COX-2 inhibitor treatment, with development of intense nuclear staining for DRAK2 at 24 h post-treatment with SC236 ( Figure 2C ).