Western blot analysis showed that aggressive cancer cell lines, such as MDA-MB-231 and MDA-MB-361, expressed higher levels of mDia1 protein than non-invasive cell lines (MCF-7, T47D, and MDA-MB-453), indicating that the expression of mDia1 was closely correlated with breast cancer cell invasion. This evidence concerns the gene DIAPH1 and breast carcinoma.