Furthermore, a quantitative apoptotic ELISA showed that the induction fold of apoptosis significantly increased with prolonged treatment or increased dose of VPA (Fig. 1f and h), suggesting that VPA induced apoptosis in the EGFR/ErbB2/ErbB3-coexpressing pancreatic cancer cells in both dose- and time-dependent manners. This evidence concerns the gene EGFR and familial pancreatic carcinoma.