Snail acetylation by histone acetyltransferase p300 in lung cancer

Background Epithelial to mesenchymal transition ( EMT ) is a complex and dynamic molecular event in lung cancer metastasis that has not yet been thoroughly investigated. EMT transcriptional factors, such as S nail, play a central role in regulation of the EMT process. In this study, we sought to identify an association between p300 and S nail in lung cancer, as well as the engagement of p300 in S nail acetylation. Methods We transfected p300 small interfering RNA into lung cancer cells to detect S nail and E ‐cadherin expression levels by real time‐ PCR . Immunoprecipitation assay was conducted to determine S nail acetylation in vivo. Bacteria‐expressed S nail was purified to analyze S nail acetylation in vitro. We further mutated lysine 187 for identifying acetylated residue in S nail. Results S nail transcription in lung cancer cells was repressed by p300 knockdown. E ‐cadherin expression was increased by transfection of p300 small interfering RNA in a dose‐dependent manner. Immunoprecipitation and Western blot assay with anti‐acetylated lysine antibody were used to confirm that S nail was acetylated by p300. A sequence coding snail gene was cloned into glutathione S ‐transferase‐tagged vector and the fusion protein was purified using glutathione. We observed S nail acetylation in vitro by incubation of recombinant S nail and p300 histone acetyltransferase domain with acetyl coenzyme A . The reduced S nail acetylation level was related to lysine mutation at position 187 of S nail. Conclusion There was a correlation between S nail and p300 expressions in lung cancer. Moreover, p300 acetylates S nail both in vivo and in vitro, and K 187 may be involved in this modification.