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Updated: Aug 8, 2026
Establishing 3D Endometrial Organoids from the Mouse Uterus
Published on: January 6, 2023
Aromatase and cyclooxygenase-2 expression in endometrial polyps during the menstrual cycle
Hugo Maia1, Kleber Pimentel, Tânia M Correia Silva
1Centro de Pesquisa e Assistência em Reprodução Humana , Salvador, Bahia, Brazil. ceparh@uol.com.br
Objectives:
To study the changes in aromatase, Ki-67 and cyclooxygenase-2 (COX-2) expression during the menstrual cycle in both endometrial polyps and normal endometria.
Patients And Methods:
Paraffin-embedded tissue samples from 118 premenopausal patients were submitted to immunohistochemistry for measurement of aromatase, COX-2 and Ki-67 expression. Fifty cases of endometrial polyps and 68 cases of disease-free endometrium were included.
Results:
The presence of aromatase expression was significantly higher in endometrial polyps than in disease-free endometria. On the other hand, changes in COX-2 and Ki-67 expression followed a similar pattern during the menstrual cycle in both groups, expression peaking during the proliferative phase and falling during the late luteal phase.
Conclusion:
A significantly higher proportion of endometrial polyps express aromatase compared with disease-free endometrium; however, no correlation was found between aromatase expression and changes in either Ki-67 or COX-2 expression during the menstrual cycle.
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