Expression of nucleophosmin in glandular epithelium of non-pregnant human endometrium during the menstrual cycle.

Background Nucleophosmin plays a critical role in embryonic development. This study aimed to examine the expression pattern of nucleophosmin in glandular epithelium of human endometrium during the menstrual cycle. Methods Endometrial tissues used for this study were obtained from 46 non-pregnant patients who underwent hysterectomy which had been performed to treat benign diseases. Nucleophosmin expression was assessed by in situ hybridization and immunohistochemistry. Results At the early-, mid- and late-proliferative phase, nucleophosmin mRNA was highly expressed in glandular epithelium of human endometrium. At the secretory phase, the expression of nucleophosmin mRNA was reduced in glandular epithelium in early-secretory phase, and the expression in mid- and late-secretory phases was not detected. Similarly, nucleophosmin protein was strongly expressed in endometrial glands throughout the proliferative phase, but was gradually reduced during secretory phase. Conclusion Nucleophosmin mRNA and protein are expressed in glandular epithelium of human endometrium throughout the menstrual cycle. Chin Med J 2011;124(16):2448-2451