SMAD2 and breast cancer: Yu et al. reported that SND1 directly binds to the histone acetyltransferase GCN5 and recruits it to the promoter regions of Smad2/3/4, thereby enhancing the transcriptional activation of Smad2/3/4 genes, potentiating the TGFβ1 signaling pathway, and promoting breast cancer metastasis [43].