Spectrum and mechanism of ACh-induced MMP gene transcription. A: actions of inhibitors of key signaling molecules on ACh-induced upregulation of MMP7 gene transcription. H508 cells were incubated with 100 μM ACh for 4 h in the absence or presence of the indicated concentrations of atropine, EGFR antibody, EGFR inhibitors (PD168393 and AG1478), MEK inhibitors (PD98059 and U0126), phosphatidylinositol 3′-kinase (PI3K) inhibitor (LY294002), and NF-κB inhibitor (SN50). MMP7 mRNA was measured by Q-PCR. Values are means ± SE of ≥3 separate experiments. B: actions of ACh on expression of MMP genes in H508 colon cancer cells. MMP mRNA was measured by Q-PCR using primers shown in Table 1. C: actions of inhibitors of key signaling molecules on ACh-induced upregulation of MMP1, MMP7, and MMP10 gene transcription. Inhibitors and concentrations are the same as those used in Fig. 5A. ↓, Attenuation; −, no effect.