| Objective:Microsatellite instability(MSI)in tumor tissues was determined by detecting mismatch repair protein(MMR),and the clinical significance of MSI in endometrial cancer and its correlation with PD-L1 were further explored,providing reference for immunotherapy of endometrial cancer.At the same time,from the perspective of economic considerations,this study explored whether the clinical significance of detecting the combination of two mismatched repair proteins is consistent with that of four proteins in endometrial cancer.Methods:The clinical data and pathological specimens of 144 patients with endometrial cancer who underwent surgical treatment in the Department of Gynecology of Affiliated Hospital of YUCU from January 2017 to December 2019 were collected.Different MMR combinations were detected by immunohistochemical method and divided into microsatellite stable group(MSS)and microsatellite unstable group(MSI).MMR(MLH1,MSH2)were defined as group A.MMR(MSH6,PMS2)were defined as group B.MMR(MLH1,MSH2,MSH6 and PMS2)were defined as group C,The relationship between MSI and age,BMI,degree of tissue differentiation,depth of muscularinfiltration,FIGO stage,pelvic lymph node metastasis,ER,PR and comorbidities(hypertension,coronary heart disease,diabetes,uterine fibroids)in group A,group B and group C was explored respectively.At the same time,the consistency of the judgment of clinical significance of endometrial cancer in group A,B and C was explored.Immunohistochemical method was used to detect PD-L1 protein,and the correlation between MSI and PD-L1 protein expression in group A,group B and group C was calculated respectively,providing A certain basis for immunotherapy of endometrial cancer.Results:1.MMR(MLH1,MSH2)were detected as group A,and there were 30 MSI and 114 MSS in group A;MMR(MSH6,PMS2)were divided into group B,in which there were28 MSI and 116 MSS in group B.MMR(MLH1,MSH2,MSH6 and PMS2)were detected in group C,in which 37 MSI and 107 MSS were detected in group C.2.MSI was associated with ER,PR and diabetes mellitus in group A(P < 0.05).After calculation,MSI(MLH1,MSH2)in ER,PR negative ratio is larger than MSS;MSI was higher in diabetic patients than that in diabetic patients.3.There was a certain correlation between MSI and tissue differentiation,ER and PR in group B(P < 0.05).The proportion of MSI(MSH6,PMS2)in low differentiation was significantly higher than that of MSS.The proportion of ER and PR negative MSI was higher than MSS.4.MSI was associated with tumor differentiation,ER,PR and diabetes mellitus in group C(P < 0.05).The proportion of MSI(MLH1,MSH2,MSH6 and PMS2)in low differentiation was significantly higher than that of MSS.The proportion of ER negative and PR negative in MSI was higher than that in MSS.MSI accounted for more MSS in patients with diabetes.5.In group A,34 patients were positive for PD-L1 in MSS,and 80 patients were negative;In MSI,15 were p D-L1 positive and 15 were negative.In group B,there were31 positive and 85 negative PD-L1 in MSS,14 positive and 14 negative PD-L1 in MSI;In group C,there were 28 p D-L1 positive and 79 negative MSS,19 MSI positive and 18 negative MSS.After calculation,the differences of MSI and PD-L1 protein expression in groups A,B and C were statistically significant,that is,the positive expression rate of PDL1 in MSI was significantly higher than that in MSS.Conclusion:1.MSI is associated with the degree of differentiation,ER and PR of endometrial cancer,and is an adverse prognostic factor of endometrial cancer.2.Detection of the combination of the two proteins(group A and B)can also reflect that MSI is an adverse factor affecting the prognosis of endometrial cancer,which has certain clinical significance and economic value.3.MSI may up-regulates the expression of PD-L1 protein in endometrial cancer tissues,providing evidence for immunotherapy of endometrial cancer. |
