Breast cancer has strong developmental origins and maternal nutrition composition may influence later-life breast cancer risk in the offspring. Our study focused on a bioactive dietary component, genistein (GE) enriched in soybean products, to investigate specific timing of maternal GE exposure that may influence preventive efficacy of GE on offspring breast cancer later in life, and to explore the potential epigenetic mechanisms. Our results indicate a time-dependent effect of maternal GE exposure on early-life breast cancer development in offspring mice. Through integrated transcriptome and methylome analyses, we identified several candidate genes showing significantly differential gene expression and DNA methylation changes. We further found maternal long-term GE treatment can induce inherited epigenetic landmark changes in a candidate tumor suppressor gene, Trp63, resulting in transcriptional activation of Trp63 and induction of the downstream target genes. Our results suggest that maternal long-term exposure to soybean GE may influence early-life epigenetic reprogramming processes, which may contribute to its temporal preventive effects on breast cancer in the offspring. This study provides important mechanistic insights into an appropriate maternal administration of soybean products on prevention of breast cancer later in offspring life.
© The Author(s) 2022. Published by Oxford University Press.