miR-532-3p: a possible altered miRNA in cumulus cells of infertile women with advanced endometriosis

RESEARCH QUESTION

Is the profile of microRNA (miRNA) altered in cumulus cells of infertile women with early (EI/II) and advanced (EIII/IV) endometriosis?

DESIGN

In this prospective case-control study, a miRNA profile including 754 targets was evaluated in samples of cumulus cells from infertile women with endometriosis (5 EI/II, 5 EIII/IV) and infertile controls (5, male and/or tubal factor) undergoing ovarian stimulation for intracytoplasmic sperm injection, using TaqMan® Array Human MicroRNA Cards A and B. The groups were compared with Kruskal-Wallis test, followed by Benjamini-Hochberg correction and Dunn's post hoc test. An in silico enrichment analysis was performed to list the possibly altered pathways in which the altered miRNA target genes are involved.

RESULTS

Only the miRNA miR-532-3p showed significant differences among the analysed groups, being down-regulated in the EIII/IV group compared with the infertile control group, as well as compared with the EI/II group. The enrichment analysis showed that some genes regulated by this miRNA are involved in important pathways for the acquisition of oocyte competence, such as the oxytocin, calcium, Wnt, FoxO, ErbB and Ras signalling pathways, as well as the oocyte meiosis pathway.

CONCLUSION

The present findings bring new perspectives to understanding the follicular microenvironment of infertile women with different stages of endometriosis. It is suggested that the dysregulation of miR-532-3p may be a potential mechanism involved in the aetiopathogenesis of endometriosis-related infertility. Further studies are needed to evaluate these pathways in cumulus cells of infertile women with the disease, as well as their impact on the acquisition of oocyte competence.

Endometriosis, Ovarian Reserve and Live Birth Rate Following In Vitro Fertilization/Intracytoplasmic Sperm Injection

Purpose To evaluate whether women with endometriosis have different ovarian reserves and reproductive outcomes when compared with women without this diagnosis undergoing in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI), and to compare the reproductive outcomes between women with and without the diagnosis considering the ovarian reserve assessed by antral follicle count (AFC). Methods This retrospective cohort study evaluated all women who underwent IVF/ICSI in a university hospital in Brazil between January 2011 and December 2012. All patients were followed up until a negative pregnancy test or until the end of the pregnancy. The primary outcomes assessed were number of retrieved oocytes and live birth. Women were divided into two groups according to the diagnosis of endometriosis, and each group was divided again into a group that had AFC ≤ 6 (poor ovarian reserve) and another that had AFC ≥ 7 (normal ovarian reserve). Continuous variables with normal distribution were compared using unpaired t-test, and those without normal distribution, using Mann-Whitney test. Binary data were compared using either Fisher's exact test or Chi-square (χ(2)) test. The significance level was set as p < 0.05. Results 787 women underwent IVF/ICSI (241 of which had endometriosis). Although the mean age has been similar between women with and without the diagnosis of endometriosis (33.8 ± 4 versus 33.7 ± 4.4 years, respectively), poor ovarian reserves were much more common in women with endometriosis (39.8 versus 22.7%). The chance of achieving live birth was similar between women with the diagnosis of endometriosis and those without it (19.1 versus 22.5%), and also when considering only women with a poor ovarian reserve (9.4 versus 8.9%) and only those with a normal ovarian reserve (25.5 versus 26.5%). Conclusions Women diagnosed with endometriosis are more likely to have a poor ovarian reserve; however, their chance of conceiving by IVF/ICSI is similar to the one observed in patients without endometriosis and with a comparable ovarian reserve.