ID proteins inhibit E-cadherin expression in breast cells.
Notes: (A) Western blot analysis of MCF10A cells with stable expression of ID1, ID2, or ID3. (B) Real-time PCR analysis of E-cadherin mRNA abundance in cell lines in (A). (C) Western blot analysis of E-cadherin protein abundance in cell lines in (A). (D) Assessment of E-cadherin promoter activity, using luciferase reporter assays, in HEK293T cells. The 1.38 kb DNA sequence containing E-cadherin promoter region was cloned upstream of the luciferase gene in a reporter construct (top image). The relative luciferase activities of luciferase reporters with E-cadherin promoter were determined in HEK293T cells, which were cotransfected with the ID1, ID2, ID3, and control vectors. For (B) and (D, bottom image), data represent mean values, with error bars indicating SEM. **P<0.05; ***P<0.001.
Abbreviations: GAPDH, glyceraldehyde 3-phosphate dehydrogenase; ID, inhibitor of DNA-binding; mRNA, messenger RNA; PCR, polymerase chain reaction; SEM, standard error of the mean; TSS, transcription start site; con, control; HF, HA and Flag; HA, hemagglutinin.