ADCY4 and breast cancer: A 2-fold increase in DNA methylation was detected for CCDC181, GCM2, ITPRIPL1, LOC643719, ZNF177, ENPP2, ADCY4 and RASSF1 in 81.5%, 70.4%, 79.6%, 66.7%, 83.0%, 77.4%, 71.7% and 73.6% of the breast cancer samples, respectively (Table 1 and Figure S2).