Figure 4
Transcriptional repression of FGF5 by its methylation of promoter CpG island and induction of FGF5 by CDDP treatment. (A) Expression levels of FGF5 and FGF5-S variants in 12 ESCC cell lines. Methylation levels obtained by a bead array analysis are also shown (high values in red, and low values in blue). Error bars mean SD (n = 3). (B) Re-expression of FGF5 in KYSE-170 and KYSE-180 cells by treatment with a DNA demethylating agent, 5-aza-dC. FGF5 expression was induced by the 5-aza-dC treatment in a dose-dependent manner. Error bars mean SD (n = 3). (C) ESCC cell lines without FGF5 methylation (KYSE-270, -410 and -450) and with methylation (KYSE-170 and -180) were treated with CDDP. In KYSE-270, -410 and -450 cells, FGF5 expression was induced by CDDP in dose- and time-dependent manners. In contrast, in KYSE-170 and -180 cells, FGF5 expression was not induced. Error bars mean SD (n = 3). (D) Overexpression of FGF5 in an ESCC cell line with methylation (KYSE-180) by transient transfection of pBApo-CMV empty or FGF5. Error bars mean SD (n = 3). (E) KYSE-180 cells transfected with pBApo-CMV empty and FGF5 were treated with CDDP. When transfected with FGF5, the cells revealed survival advantage after CDDP treatment. Error bars mean SD (n = 3).
