Regional Methylome Profiling Reveals Dynamic Epigenetic Heterogeneity and Convergent Hypomethylation of Stem Cell Quiescence-Associated Genes in Breast Cancer Following Neoadjuvant Chemotherapy.

Neoadjuvant chemotherapy (NAC) induces a pathological complete response (pCR) in ~ 30% of patients with breast cancer. However, aberrant DNA methylation alterations are frequent events during breast cancer progression and acquisition of chemoresistance. We aimed to characterize the inter- and intra-tumor methylation heterogeneity (MH) in breast cancer following NAC.