Correlation Between PD-L1 Expression And Epithelial-mesenchymal Transition In Colorectal Cancer

Purpose: The expression of programmed death ligand-1(PD-L1)and epithelial-mesenchymal transition(EMT)related factors including E-cadherin,vimentin,Snail,ZEB1 in colorectal cancer patients and their correlation with various clinicopathological factors were observed.To explore the correlation between PD-L1 and EMT factors is helpful to explore the pathways of PD-L1 participation in EMT processes of colorectal cancer.Methods: A total of 90 paraffin specimens of colorectal cancer tissues with relatively complete clinical and pathological data were selected and collected from the pathology department of The first affiliated hospital of bengbu medical college.The normal 30 cases of colorectal mucosal tissue confirmed by pathology were selected as control.The expression of PD-L1 and EMT related factors in the above tissues was detected by immunohistochemical staining,and the data were analyzed by statistical software spss25.0.Results: 1.In 90 cases of colorectal cancer,the positive expression rate of E-cadherin in tumor significantly lower than that in normal colorectal mucosa,while the positive expression rate of PD-L1,vimentin,Snail,ZEB1 in tumor tissue was significantly higher than that of normal colorectal mucosa for control.2.The positive rate of PD-L1 was positively correlated with the degree of differentiation(P<0.05).The positive rate of cadherin was negatively correlated with the degree of differentiation,lymph node metastasis and TNM stage(P<0.05).The positive rate of vimentin was positively correlated with differentiation degree,lymph node metastasis and TNM stage(P<0.05).The positive rate of Snail,ZEB1 was positively correlated with lymph node metastasis and TNM stage(P<0.05).3.There was a negative correlation between PD-L1 expression and E-cadherin expression(r=-0.257,P<0.05),there was a positive correlation between PD-L1 expression and vimentin expression(r=0.269,P<0.05),there was a positive correlation between PD-L1 expression and Snail expression(r=0.381,P<0.001),there was a negative correlation between Snail expression and E-cadherin expression(r=-0.505,P<0.05),there was a positive correlation between PD-L1 expression and ZEB1 expression(r=0.241,P<0.05),there was a negative correlation between ZEB1 expression and E-cadherin expression(r=-0.252,P<0.05),there was a positive correlation between PD-L1 expression and EMT expression(r=0.299,P<0.05).Conclusions: 1.The abnormal expression of PD-L1 and EMT related factors in colorectal cancer suggests that PD-L1 and EMT related factors may be involved in the development of colorectal cancer.2.There is a correlation between PD-L1 and EMT related factors and many clinicopathological factors,which may be related to malignant biological behavior of colorectal cancer.3.The expression of PD-L1 is related to the expression of many EMT related factors,indicating that PD-L1 may participate in the EMT process through some process.