CD44 and breast cancer: So et al. [4] showed growing malignant potential of MCF10 cell lines including MCF10DCIS with the decrease of expression of the standard 85-KDa isoform of CD44 and an increased expression of its 10–250 KDa variants, namely, CD44v, CD44v3, and CD44v6, and categorized them as markers of breast cancer progression.