B- and c-series of gangliosides are over-expressed in neuro-ectoderm-related cancers, including breast cancer. It has been shown that GD3 ganglioside is over-expressed in about 50% of invasive ductal breast carcinoma and the GD3 synthase (GD3S) gene displays higher expression among estrogen receptor (ER) negative breast tumors. We previously showed that GD3S expression in MDA-MB-231 breast cancer cells induces the expression of GD2 and increased cell proliferation and migration via a GD2-dependent activation of c-Met receptor. Here, we show that in ER-positive MCF-7 breast cancer cells, GD3S expression resulted in an increase of GD1b, which was associated with a decrease of GM1a and GM2. Meanwhile, GD3S expressing MCF-7 cells exhibited an increased migration without any modification of proliferation rate. Therefore, GD3S expression can result in different modifications of both ganglioside profiles and cell phenotypes depending on breast cell types.