Abstract: Objective：To investigate the expression of let-7i in endometrial carcinoma tissues and its clinical significance. Methods: Forty cases of endometrial carcinoma, twenty cases of atypical hyperplasia and thirty cases of normal endometrium tissues were collected from 2011 April to 2014 December at The First Hospital of Hebei Medical University. Poly（Ａ）-RT-qPCR was employed to test the expression of let-7i in different endometrial tissues. The statistical analyses were performed between the expression of let-7i and the clinicopathological characteristics. Results: The expression of let-7i was lower in endometrial caｒｃｉｎｏｍａ ｔｉｓｓｕｅｓ ｔｈａｎ ｔｈａｔ ｏｆ ａｔｙｐｉｃａｌ ｈｙｐｅｒｐｌａｓｉａ ａｎｄ ｎｏｒｍａｌ ｅｎｄｏｍｅｔｒｉｕｍ ｔｉｓｓｕｅｓ， ａｎｄ ｔｈｅ ｄｉｆｆｅｒｅｎｃｅ ｗａｓ ｓｔａｔｉｓｔｉｃａｌｌｙ ｓｉｇｎｉｆｉｃａｎｔ（Ｐ＜０．０１）． Ｔｈｅ ｅｘｐｒｅｓｓｉｏｎ ｏｆ ｌｅｔ－７ｉ ｉｎ ｄｉｆｆｅｒｅｎｔ ａｇｅ， ｐａｔｈｏｌｏｇｉｃａｌ ｔｙｐｅ， ＦＩＧＯ ｓｔａｇｅｓ， ｐａｔｈｏｌｏｇｉｃａｌ ｇｒａｄｅｓ ｏｆ ｅｎｄｏｍｅｔｒｉａｌ ｃａｒｃｉｎｏｍａ ｐａｔｉｅｎｔｓ ｈａｄ ｎｏ ｓｉｇｎｉｆｉｃａｎｔ ｄｉｆｆｅｒｅｎｃｅ （Ｐ＞０．０５）， ａｎｄ ｉｔｓ ｅｘｐｒｅｓｓｉｏｎ ｉｎ ｅｎｄｏｍｅｔｒｉａｌ ｃａｒｃｉｎｏｍａ ｐａｔｉｅｎｔｓ ｗｈｅｔｈｅｒ ｗｉｔｈ ｈｙｐｅｒｔｅｎｓｉｏｎ， ｄｉａｂｅｔｅｓ， ｌｙｍｐｈ ｎｏｄｅ ｍｅｔａｓｔａｓｉｓ ａｎｄ ＥＲ－ｐｏｓｉｔｉｖｅ， ＰＲ－ｐｏｓｉｔｉｖｅ ｈａｄ ｎｏ ｓｔａｔｉｓｔｉｃａｌ ｄｉｆｆｅｒｅｎｃｅ （Ｐ＞０．０５）. Conclusions: The expression of let-7i was down-regulated in endometrial carcinoma tissues, and it may regulate the origination of endometrial carcinoma.

Key words: Endometrial neoplasms, MicroRNAs, Let-7i, Reverse transcriptase polymerase chain reaction