MiR-1301 Affects Migration And Invasion Of Colorectal Cancer By Targeting STAT3

Background:Colorectal cancer(CRC)is a high-frequency malignant tumor of the digestive tract around the world,and its cause is related to heredity and eating habits.The latest statistics show that the incidence of CRC ranks fourth in malignant tumors,and the mortality rate ranks second only to lung cancer.In recent years,the incidence of CRC in China has also shown a significant upward trend.The late metastasis of the tumor is the main cause of the deterioration of the patient's condition.So,finding new tumor markers for early diagnosis and personalized treatment is the key to tumor prevention.A large number of studies have shown that an important epigenetic regulatory mode,micro RNA(mi RNA),which is found to be abnormally expressed in most patients with colorectal cancer and is the leading cause of invasion and metastasis of colorectal cancer.A variety of mi RNAs have been found to be abnormally expressed in colorectal cancer tissue now,as a member of many mi RNAs,mi R-1301 have been confirmed its inhibitory effect in other tumors,but its role in colorectal cancer has not been reported.Threrefore,this study will explore the effects of mi R-1301 on the migration and invasion of CRC through bioinformatics analysis,related functional experiments and molecular mechanism studies.then,we will confirm whether it can be used as a new marker of CRC to provide a theoretical basis for the diagnosis and target therapy of CRC.Methods:1.The TCGA database was used to analyze the expression difference of mi R-1301 in tumor tissues and normal tissues of colorectal cancer patients.2.The expression level of mi R-1301 was verified by q RT-PCR in 28 colorectal cancer tissue samples(provided by the Fourth Military Medical University).3.Colorectal cancer cells were transfected with mi R-1301 mimics to overexpress mi R-1301,transfected with mi R-1301 inhibitor to inhibit mi R-1301 expression.CCK-8 proliferation assay,wound scratch and Transwell experiment were used to detect the proliferation,migration and invasion capabilities of cells,respectively.4.The bioinformatics software mi Randa and Target Scan were used to predict the target gene of mi R-1301.GO and pathway methods were used to analyze their downstream regulatory networks.Then,the dual luciferase reporter assay,Western Blot and Rescue experiments were used to verify the binding relationship between mi R-1301 and STAT3.Results:1.TCGA data show that mi R-1301 expression in CRC patients is significantly down-regulated compared with normal tissues(P<0.0001)and its expression level is related to metastasis(M stage)(P<0.05).2.Among 28 clinical samples,the expression level of mi R-1301 in normal tissues is significantly higher than that in colorectal cancer tissues(P<0.0001).3.CCK-8 experiment results showed that the expression of mi R-1301 did not affect the proliferation of CRC cells;Transwell invasion test results showed that inhibiting the expression of mi R-1301 can promote the invasion ability of SW480 cells(P<0.01);overexpression of mi R-1301 inhibited the invasion ability of Lo Vo cells(P<0.01),inhibiting the expression of mi R-1301 can promote the invasion of Lo Vo cells(P<0.001),and the scratch test showed the same results as the Transwell invasion test.4.Bioinformatics analysis shows that there are two mi R-1301 binding sites on STAT3;dual luciferase gene report detection,Western Blot,and Rescue experiments show that mi R-1301 exerts its tumor suppressor effect in CRC by directly targeting STAT3.Conclusion:Mi R-1301 inhibits the migration and invasion of colorectal cancer cells by targeting STAT3,and it is speculated that it has a blocking effect on colorectal metastasis,which is expected to be a new target in the diagnosis and treatment of colorectal cancer.