Histone methyltransferases regulate the transcriptional expression of ERα and the proliferation of tamoxifen-resistant breast cancer cells

Purpose Although tamoxifen remains the frontline treatment for ERα-positive breast cancers, resistance to this drug limits its clinical efficacy. Most tamoxifen-resistant patients retain ERα expression which may support growth and progression of breast cancers. Therefore, we investigated epigenetic regulation of ERα that may provide a rationale for targeting ERα in these patients.