BCYRN1 and ductal breast carcinoma in situ: BC200 levels are aberrantly elevated in several types of malignancy (Chen et al., 1997, Samson et al., 2018); these include breast cancer, where high BC200 expression is associated with advanced stages of ductal carcinoma in situ (Chen et al., 1997, Iacoangeli et al., 2004, Singh et al., 2016).