RIPK4 and breast cancer: To assess the expression pattern of RIPK4 in BC, we analysed the RIPK4 protein level in several BC cell lines, including BIU87, 5637, T24, EJ and RT4 cells, and found that RIPK4 levels were high in T24, EJ and RT4, which show strong invasiveness, and low in BIU87 and 5637, which show weak invasiveness (Fig. 1a).