Fetal programming theory: implication for the understanding of endometriosis.

Comparison of the transcriptomes and proteomes of the decidualization-specific genes that express high vs low levels of the eutopic and ectopic endometrium of women with endometriosis compared with controls, could be useful in understanding the pathogenesis of endometriosis. Genome-wide comparison between decidual tissue and non-decidual tissue identified many genes significantly modulated in the process of decidualization. Comparison of eutopic endometrium and endometriotic sites also revealed up- and down-regulated genes. A combined analysis of the experimental data showed specific genes up-regulated both at the endometriotic site and in the decidualization process, representing a broad diversity of molecular functions, including cell cycle regulation, angiogenesis and adhesion molecules. In contrast, down-regulated genes identified in endometriosis among genes overexpressed in decidualization encode Müllerian embryogenesis, which includes transcription factors, hormonal regulation and cytokine expression. The mechanism responsible for insufficient decidualization in endometriosis may be mediated through down-regulation of the Müllerian embryogenesis-related genes. In conclusion, a range of decidualization resistance has been associated with endometriosis. Future study will identify the putative mechanisms relating epigenetic changes of decidualization susceptibility genes in early life to the risk of developing endometriosis in adulthood.