No reports have been published so far on possible associations between promoter methylation and gene expression in the TRIM family, including TRIM9. TRIM9 is known to be up-regulated by interferons, suggesting that another mechanism than promoter methylation may be more important in the regulation of gene expression in breast cancer tissues (Carthagena et al. 2009) although promoter methylation seems to play a significant role in vitro as we have shown in the present study. Here, TRIM9 is linked to breast carcinoma.