Endometriosis is a complex gynecological disease which occurs in 10% of reproductive age women. The disease is characterized by the presence and growth of endometrial tissue outside the uterus, causing pelvic pain, and infertility. The pathogenesis of endometriosis is not clearly defined. However, the disease is thought to be principally caused by the shedding of viable endometrial cells into the peritoneal cavity by retrograde menstruation, followed by their implantation and growth on the surface of pelvic organs. The formation of a lesion depends on the survival, attachment, growth, neoangiogenesis, and invasion of the endometrial cells at the ectopic sites. This may be due to abnormalities of the eutopic endometrium itself, predisposing the cells to survive and implant ectopically. Several studies have shown aberrant expression of genes/ proteins in endometriosis that are involved in regulating cellular processes like adhesion, proliferation, angiogenesis, immune dysfunction, and others. K-252c Recently, using proteomics approach, we have investigated the differential expression of proteins in eutopic endometrium from women with and without endometriosis. In this study it was observed that DJ-1 protein is upregulated in eutopic endometrium of women JNJ 10397049 having endometriosis compared with controls. These findings suggest that DJ-1 may be involved in the pathogenesis of endometriosis. The human DJ-1 gene comprises of seven exons and maps to 1p36.2�C36.3, where many chromosome aberrations in cancers have been reported. DJ-1 is ubiquitously present in cells and has been suggested to be a novel mitogen-dependent oncogene involved in a Ras-related signal transduction pathway. More recently, high DJ-1 levels have been reported in various tumors, suggesting that abnormally expressed DJ-1 may play a role in cancer initiation and/or progression under certain circumstances and may be a potential anticancer target. DJ-1 protein affects cell survival, proliferation, and growth of cells in part, by modulating cellular signaling cascades such as PTENPI3K/ Akt and altering p53 activity. DJ-1 has shown to convey protection against stresses and proteasome inhibition. It has been suggested that DJ-1 plays a role in antioxidative stress by eliminating reactive oxygen species and in transcriptional regulation of its target genes. The pathological significance of DJ-1 in endometriosis has not been elucidated.