Rare cilia-positive cancer cells are positive for Cytokeratin 5. (A) Images show nuclei (blue), cytokeratin 5 (white), cilia (red), and centrosomes (green) in cells from the following tissue: reduction mammoplasties (RM) and histologically normal epithelium (HNE) adjacent to cancer and invasive cancers of four different cancer subtypes: luminal A and luminal B, Her2-positive, and triple negative. Insets show a magnified ciliated CK5-positive cell. (B) Boxplot represents median percent of cilia expressed on CK5-negative and CK5-positive cells in the following breast tissue types: basal epithelial cells of normal breast reduction mammoplasties (RM Basal, n = 12), luminal epithelial cells of normal breast reduction mammoplasties (RM Luminal, n = 12), basal cells in histologically normal epithelium adjacent to cancer (HNE Basal, n = 15), luminal cells in histologically normal epithelium adjacent to cancer (HNE Basal, n = 15), cancer cells in invasive cancers of the four breast cancer subtypes (Luminal A (LUM A, n = 37), Luminal B (LUM B, n = 10), Her2-positive (Her2+, n = 6), and Triple Negative (TN, n = 12)). Statistical significance (** = P <0.01, *** = P <0.001) was determined by performing logistic regression compared to normal RM.