Figure 4. HDAC-inhibitors (HDACi) inhibit claudin-2 transcription to regulate its expression in differentiating colon cancer cells.

(A-B) qRT-PCR of claudin-2 and P-21^waf1/cip1 using total RNA isolated from SAHA or NaB-treated cells. ; (C-D) Claudin-2 promoter activity in control and SAHA or NaB-treated CRC cells.; (E-F) Immunoblot and densitometry analysis of claudin-2 in total cell lysate of colon cancer cell subjected to SAHA with/without EGF (100ng/ml). EGF-alone treatment was used as positive control.; (G-H) Claudin-2 promoter activities in response to NaB or SAHA treatments. Three independent experiments were done and data is presented as mean ± S.E.M. ^*P<0.05, ^**P<0.01 and ^*** P<0.001 versus control.