In order to provide a justification for studies concerning the role of RBMS 3 in EMT in breast cancer, we performed an analysis of the correlation between RBMS 3 immunohistochemical expression in cancer cells and the expression of Twist Family BHLH Transcription Factor 1 (TWIST 1), SNAIL (Snail Family Transcriptional Repressor 1), Snail Family Transcriptional Repressor 2 (SLUG), Epithelial Cadherin (E-CAD), Neural Cadherin (N-CAD) and Zinc finger E-box-binding homeobox 1 (ZEB 1) in 449 cases of breast cancer. The gene discussed is SNAI2; the disease is cancer.