ADAM23 and breast cancer: In BC patients with mes CTC+ in circulation, significant lower methylation levels of the ADAM23 gene were identified in PT and LNM tissues than in the tissues of patients with mes CTC- (4.79% vs. 11.89%, P = 0.023 for PTs and 4.29% vs. 11.31%, P = 0.024 for LNMs) (Fig. 3).