Expression Of Chemokine Receptor 6 And Its Correlation With Epithelial-mesenchymal Transition In Colorectal Adenocarcinoma And Matched Liver Metastasis

Objective:To detect the expression of chemokine receptor 6(CCR6)in colorectal adenocarcinoma tissues and their paired liver metastases,and to analyze the correlation between chemokine receptor 6 and E-cadherin and vimentin,to explore the possible mechanism of CCR6 mediating colorectal liver metastasis,to provide experimental basis for elucidating the mechanism of liver metastasis of colorectal cancer.Methods:To collect 62 cases of colorectal cancer from the First Hospital of Shanxi Medical University and Shanxi Province Tumor Hospital from 2009 to 2017,and 20 of them were surgically resected and archived in the same period.Immunohistochemistry was used to detect the expression of CCR6 and EMT-related proteins E-cadherin and vimentin in colorectal cancer tissues and matched liver metastases.According to the average percentage of positive cells in each slice and cell staining intensity were scored in two aspects:(1)the average percentage of positive cells: not stained 0 points,0 to 25% for 1point,25% to 50% for 2 points,>50% for 3 points;(2)Cell staining intensity score: 0points for no staining,1 for light yellow,2 points for Brownish yellow,3 divided brown.The scores are multiplied by 0 to 3 in(-)or(±),and 4 to 9 in(+).SPSS19.0 software was used for analysis.Count data were analyzed by χ2 test.Multivariate analysis was performed using Logistic regression analysis.Correlation analysis was performed using Pearson column contact numbers.The test level was taken as both sides α=0.05.Results:1.In colorectal adenocarcinoma,the positive expression rate of CCR6 was 66.1%(41/62).The expression of CCR6 was correlated with tumor lymph node metastasis and TNM stage(P<0.05),no correlation with patient’s gender,age,tumor location,tumor maximal diameter and the degree of differentiation,and the difference was not statistically significant(P>0.05).The positive rate of E-cadherin was 67.7%(42/62),and the positive rate of vimentin was 79.0%(49/62).E-cadherin and vimentin expression were correlated with tumor lymph node metastasis and TNM staging(P<0.05).2.In colorectal adenocarcinoma,CCR6 was associated with TNM staging(P=0.005),E-cadherin expression(P=0.030),and vimentin expression(P=0.015).3.In liver metastasis,CCR6 was correlated with the expression of E-cadherin(r=0.579,P=0.007)and vimentin(r=0.509,P=0.022).Conclusion:CCR6 and EMT related markers E-cadherin and vimentin are highly expressed in colorectal cancer and liver metastases.CCR6 is associated with E-cadherin and vimentin expression,suggesting that CCR6 induce liver metastasis by regulating EMT in colorectal cancer.