Differences in the stem cell-associated gene expression of eutopic endometrium from endometriosis patients in comparison to healthy women

Objective:

To investigate possible differences in the gene expression of eutopic endometrium of healthy women compared to the eutopic endometrium of endometriosis patients with a special emphasis on stem cell-associated genes.

Materials and methods:

Endometrial biopsies consisting of endometrial stromal cells (ESCs) and endometrial epithelial cells (EECs) of patients with and without endometriosis (n = 19 healthy controls, n = 19 endometriosis ASRM I-II°, n = 11 ASRM III-IV°) were investigated via real-time PCR and immunohistochemistry for a panel of stem cell-associated genes.

Results:

To further investigate the stem cell nature of endometriosis, stem cell associated genes, especially those required for the reprogramming of differentiated cells, were analysed. NANOG and Klf-4, but not c-Myc, showed significant upregulation only in the Grade III-IV group compared to the healthy group. Oct-4, however, was significantly upregulated in both Grade I-II and Grade III-IV endometriosis groups when compared to the control. SOX-2 showed a steady increase from normal to endometriosis group, which was significant for Grade III-IV. Musashi-1, as a maintainer of stem cell function, is also significantly upregulated in all grades of endometriosis when compared to the control.

Conclusion:

Our results indicate a significant upregulation of various stem cell-associated markers, in the eutopic endometrium of endometriosis patients in comparison to healthy women. This supports the stem cell nature of endometriosis and should be further explored. On-going investigations will further elucidate the interplay of the regulated genes.