Detection of the pan neuronal marker PGP9.5 by immuno-histochemistry and quantitative PCR in eutopic endometrium from women with and without endometriosis.

PURPOSE: To assess endometrial gene as well as protein expression of neuroendocrine and supposedly endometriosis-associated product PGP9.5 and pain symptoms in women with endometriosis and controls undergoing laparoscopy, using molecular biological and immuno-histochemical approaches in the same patients. METHODS: Biopsy of eutopic endometrium from 29 patients by sharp curettage, and preparation of paraffin blocks. Determination of PGP9.5 gene expression and protein abundance using qPCR and immuno-histochemistry. RESULTS: qPCR; The PGP9.5 mRNA expression level between women with (N = 16) and without (N = 13) endometriosis was not different, regardless of pain symptoms or menstrual cycle phase. PGP9.5 expression was higher in women who reported pain compared to those who did not; however, this association was not statistically significant. The expression of PGP9.5 mRNA was higher in women with endometriosis and pain during the proliferative than in the secretory phase (P = 0.03). Furthermore, in the first half of the cycle, the abundance of the PGP9.5 transcript was also significantly higher in endometriosis patients compared to those without (P = 0.03). Immuno-histochemistry; Thirteen of the 16 endometriosis patients showed positive PGP9.5 immuno-reactivity in the endometrium, whereas no such signal was observed in women without endometriosis. The absolute number of nerve fibres per mm(2) in women with endometriosis was similar, regardless of the pain symptoms. CONCLUSIONS: PGP9.5 mRNA expression is increased in the proliferative phase of endometriotic women with pain. The presence of nerve fibres was demonstrated by a PGP9.5 protein signal in immuno-histochemistry and restricted to patients with endometriosis. Based on these results, however, there did not appear to be a direct association between the gene expression and protein abundance in women with and without endometriosis or those that experienced pain.

Angiogenesis, lymphangiogenesis and neurogenesis in endometriosis.

Endometriosis is a common, benign gynecological disease affecting 10 - 15% of reproductively aged women. It is characterized by the presence of endometrial-like tissue at sites outside the uterus. The most widely accepted theory of endometriosis pathogenesis proposes that shed menstrual endometrium can reach the peritoneum, implant and grow as endometriotic lesions. Angiogenesis, lymphangiogenesis and neurogenesis are implicated in successful ectopic establishment and the generation of endometriosis-associated symptoms. This review considers these processes as they occur in the eutopic endometrium and ectopic endometriotic lesions of women with endometriosis. Their regulation is inter-connected and complex. Dysregulation in endometriosis occurs on a background of accumulating evidence that endometriosis is an endometrial disease with underlying genetic influences and cross talk with endometriotic lesions. Understanding the roles of angiogenesis, lymphangiogenesis and neurogenesis in endometriosis pathophysiology is essential for the development of novel therapeutic approaches.