Objective: To investigate the expression of Beta-lactamase-like protein (LACTB) in endometrial cancer tissues and its clinical significance. Methods: The protein expression of LACTB, etrogen receptor and progesterone receptor in 89 cases of endometrial cancer and 21 cases of normal endometrial tissues were assessed by immunohistochemistry. Meanwhile, the expression of estrogen receptor and progesterone receptor in endometrial cancer tissues was assessed by immunohistochemistry．The known Kaplan-Meier Plotter database was used to analyze the relationship between the expression changes of LACTB mRNA transcriptome sequencing and the prognosis of endometrial cancer in endometrial cancer tissues. Results: The position rate of LACTB protein expression in endometrial carcinoma tissues was significantly lower than that in normal endometrial tissues(P<0.05). The expression of LACTB protein in endometrial carcinoma tissues was not associated with age grouping(P>0.05). Compared with clinical stage Ⅰ-Ⅱ, the position rate of LACTB protein expression was significantly decreased in clinical stage Ⅲ-Ⅳ(P<0.05). The positive expression rate of LACTB protein was lower in type Ⅰ endometrial cancer than in type Ⅱ endometrial cancer, while the difference was not statistically significant. The position rate of LACTB protein expression was correlated with estrogen receptor and progesterone receptor(P<0.05). The overall survival and progression-free survival of the LACTB positive expression group were higher than the negative expression group, while there was no stastical difference. Conclusion: Low expression of LACTB in endometrial cancer tissues may be an important molecule involved in the progression of endometrial cancer, which is associated with etrogen receptor and progesterone receptor expression.

［Key words］endometrial cancer; Beta-lactamase-like protein(LACTB); etrogen receptor; progesterone receptor; immunohistochemistry; prognostic analysis