RPLP1 Is Up-Regulated in Human Adenomyosis and Endometrial Adenocarcinoma Epithelial Cells and Is Essential for Cell Survival and Migration In Vitro.

Adenomyosis is defined as the development of endometrial epithelial glands and stroma within the myometrial layer of the uterus. These "ectopic" lesions share many cellular characteristics with endometriotic epithelial cells as well as endometrial adenocarcinoma cells, including enhanced proliferation, migration, invasion and progesterone resistance. We recently reported that the 60S acidic ribosomal protein P1, RPLP1, is up-regulated in endometriotic epithelial cells and lesion tissue where it plays a role in cell survival. To evaluate if a similar pattern of expression and function for RPLP1 exists in adenomyosis and endometrial cancer, we examined RPLP1 expression in adenomyosis and endometrial cancer tissue specimens and assessed its function in vitro using well-characterized cell lines. A total of 12 control endometrial biopsies and 20 eutopic endometrial and matched adenomyosis biopsies as well as 103 endometrial adenocarcinoma biopsies were evaluated for RPLP1 localization by immunohistochemistry. Endometrial adenocarcinoma cell lines, Ishikawa, HEC1A, HEC1B and AN3 were evaluated for RPLP1 protein and transcript expression, while in vitro function was evaluated by knocking down RPLP1 expression and assessing cell survival and migration. RPLP1 protein was up-regulated in eutopic epithelia as well as in adenomyosis lesions compared to eutopic endometria from control subjects. RPLP1 was also significantly up-regulated in endometrial adenocarcinoma tissue. Knockdown of RPLP1 in endometrial adenocarcinoma cell lines was associated with reduced cell survival and migration. RPLP1 expression is up-regulated in eutopic and ectopic adenomyotic epithelia as well as in the epithelia of endometrial cancer specimens. In vitro studies support an essential role for RPLP1 in mediating cell survival and migration, processes which are all involved in pathophysiology associated with both diseases.

The Relationship and Expression of miR-451a, miR-25-3p and PTEN in Early Peritoneal Endometriotic Lesions and Their Modulation In Vitro.

BACKGROUND: miR-451a can function as a tumor suppresser and has been shown to be elevated in both endometriotic lesion tissue and serum from women with endometriosis. To further explore the role of miR-451a in the pathophysiology of endometriosis, specifically, further evaluating its association with the tumor suppressor, phosphatase and tensin homolog (PTEN), we examined their expression in individual endometriotic lesion tissue to gain insight into their relationship and further explore if miR-451a regulates PTEN expression. METHODS: A total of 55 red, peritoneal endometriotic lesions and matched eutopic endometrial specimens were obtained from 46 patients with endometriosis. miR-451a, miR-25-3p and PTEN mRNA levels were assessed by qRT-PCR and reported for each matched eutopic and ectopic sample. To evaluate miR-451a and miR-25-3p expression of miR-25-3p and PTEN, respectively, 12Z cells (endometriotic epithelial cell line) were transfected and miR-25-3p expression was assessed by qRT-PCR, while PTEN protein expression was assessed by Western blotting. RESULTS: PTEN and miR-25-3p expression exhibited an inverse relationship, as did miR-25-3p and miR-451a in individual lesions. Over-expression of miR-451a in 12Z cells resulted in down-regulation of miR-25-3p, while up-regulation of miR-25-3p resulted in down-regulation of PTEN protein expression. CONCLUSIONS: By assessing individual endometriotic lesion expression, we discovered an inverse relationship between miR-451a, miR-25-3p and PTEN, while in vitro cell transfection studies suggest that miR-451a may regulate PTEN expression via modulating miR-25-3p.