We demonstrated that CD90 (a mesenchymal stem cell marker) was highly expressed in the most aggressive basal-like breast tumor cell line (Hs578T), when compared with the non-tumorigenic one (MCF10A) or with the less aggressive lines (MDA-MB-231 and MDA-MB-435) [10], indicating that CD90 expression increased according to the malignancy degree of the cell lines, positively correlating to high malignancy grade in mammary carcinoma [9]. Here, THY1 is linked to breast neoplasm.