Cumulus cell evaluation in infertile patients with minimal or mild endometriosis

Posted May 24, 2022

A study conducted by the INCT Hormona team at the University of São Paulo (USP), in Ribeirão Preto, investigated the etiopathogenic mechanisms of infertility associated with early-stage endometriosis (minimal and mild). The study, titled “Transcriptomic analysis of cumulus cells shows altered pathways in patients with minimal and mild endometriosis,” presents important novel data on this relationship and can be read in full at https://pubmed.ncbi.nlm.nih.gov/ 35388025/.

According to professor and researcher Dr. Paula Navarro, the study is essential for discovering new infertility treatments. “Understanding why patients with minimal or mild endometriosis (grades 1 and 2) may be infertile is more complicated because they do not present altered pelvic anatomy nor tube obstruction, and they do not have many adhesions. Therefore, understanding why they may be infertile helps us to test and investigate new forms of treatment,” she states.

“Expanding treatment possibilities is important both due to the prevalence of the disease and the fact that currently there is no drug treatment for infertility in endometriosis. The only available treatments are assisted reproduction and surgery, with limited access to the general population,” she explains.

Dr. Navarro says that, in previous studies, the team found that patients with early-stage endometriosis may be at greater risk of having compromised oocyte quality, and this worsening may be related to infertility. “Considering that invasive oocyte evaluation is not routinely feasible, we conducted indirect evaluation using cumulus cells, which are cells surrounding the oocyte during its development and maturation. Therefore, they are important for securing oocyte quality and protection,” she explains.

In the study, the team performed transcriptome or transcription profile analysis of cumulus cells from infertile patients with early-stage endometriosis compared to infertile patients without endometriosis to try to better understand the mechanisms related to oocyte alterations.

The study shows that the transcription profile of cumulus cells from infertile patients with minimal or mild endometriosis has 26 differentially expressed genes compared to controls. “The enrichment analysis identified some molecular processes that were altered: cytokine-cytokine receptor interactions, chemokine signaling, tumor necrosis factor signaling, nucleotide-binding and oligomerization domain-like receptor signaling, nuclear factor kappa B signaling, and inflammatory response,” the researcher explains.

Dr. Navarro believes that, after these results, further studies should be conducted. “Our team is already conducting some research, currently in animals. We are trying to better characterize a model of infertility and endometriosis in mice, and one of the next steps is to test therapeutic interventions,” she says. “If the research is promising, we will begin controlled clinical trials with humans,” she concludes.