Expression And Clinical Significance Of USP4 In Colorectal Cancer

Objective: The purpose of this study is to investigate the expression of USP4 in colorectal cancer and its correlation with clinicopathological features and related tumor invasion and metastasis factors and to explore the mechanism of proliferation,invasion and metastasis of USP4 in colorectal cancer and to analyze the effect of USP4 on the occurrence and development of colorectal cancer,which will provide the foundation for further exploration of the molecular mechanism of USP4.Methods: Randomly selected 120 cases of paraffin specimen of colorectal cancer diagnosed by the pathology department of Affiliated Hospital of Guilin Medical University from January 2014 to December 2016.Then 20 cases of normal colorectal tissue were randomly selected as the control group.By using immunohistochemical method,the expressions of USP4,Ki67,VEGF and MMP2 were detected,and the relationship between the expressions of proteins and clinicopathological features was statistically analyzed.After transfecting si RNA into human colon cancer cell lines,the effects of reducing USP4 on the proliferation and migration of colorectal cancer cells were detected through cell proliferation experiment and cell scratch experiment,which further clarify the mechanism of USP4 in colorectal cancer.Results: 1.The expression of USP4 was low in normal colorectal mucosa,but high in colorectal cancer.The difference was statistically significant(P<0.001);2.The expression of USP4 in colorectal cancer was closely related to the expression of Ki67,VEGF and MMP2.The difference was statistically significant(P<0.05);3.The expression of USP4 protein was negatively correlated with the degree of tumor differentiation and positively correlated with depth of invasion and lymph node metastasis.It has no statistical significance with age,gender,tumor location and tumor size(P>0.05);4.After reducing the expression of USP4,the scratch experiment showed that the healing rate of tumor cells transfection group was significantly lower than that of the control group;the proliferation experiment showed that cell adhesion of the tumor cell transfection group was decreased and the number of cell proliferation was reduced.Conclusions: 1.USP4 is highly expressed in colorectal cancer,and its expression level is closely related to the malignancy and invasiveness of the tumor.2.The expression of USP4 is positively correlated with the expression of VEGF and MMP2 in colorectal cancer,which suggests that they may promote the evolution and progress of tumor in some degree.Therefore,the combined detection of USP4,VEGF and MMP2 is expected to be a potential marker for the evaluation of disease,prognosis judgment and targeted therapy;3.The proliferation,invasion and migration of human colorectal cancer cells are obviously weakened by reducing the expression of USP4 protein,which indicate that USP4 has an important relationship with the occurrence and development of colorectal cancer.