The Study Of MiR-126Invasion And Metastasis Suppression Function And Its Mechanism Of Colon Cancer

Objective:To study the miR-126’s fuction of inhibition of cell proliferation, invasion and metastasis of colon cancer.And to study the miR-126’s fuction of regulation of CXCR4and RhoA signal pathway.Methods:1. Construct stable overexpression of miR-126colon cancer cell line HCT116and stability interfere with miR-126colon cancer cell line SW480with lentiviral vector.2. Realtime PCR detects the expression of CXCR4and RhoA signaling pathway molecules in stable expression and interfere with miR-126colon cancer cell lines HCT116and SW480.3. Execute subcutaneous tumor formation and tail vein tumor formation test in nude mice with stable expression and interfere with miR-126colon cancer cell lines.4. Detect the expression of miR-126,CXCR4and RhoA signaling pathway molecules in human colon cancer tissue microarray.Results:1. The expression of miR-126in experimental group of HCT116increased5.08times than the control group (P<0.05).The expression of miR-126in experimental group of SW480was0.128times of the control group (P<0.05). Stable overexpression of miR-126cell line HCT116and stable interference of miR-126cell line SW480was successfully constructed.2. The realtime PCR results show that the expression of CXCR4and RhoGEF of the stable overexpression of miR-126colon cancer cell line HCT116experimental group was significantly lower than the control group, but RhoGAP were significantly increased (P<0.05); The expression of CXCR4and RhoGEF of the stable interference of miR-126colon cancer cell line SW480experimental group were significantly higher than the control group, but RhoGAP was significantly lower (P <0.05).3. Nude mice tumor formation experiment results show that the mean tumor volume of overexpression of miR-126experimental group was significantly less than the control group tumor volume (P<0.05). The mean tumor volume of interference of miR-126experimental group was significantly greater than the control group tumor volume (P<0.05). Tail vein tumor formation experiment results show that the average number and size of lung metastases of overexpression of miR-126experimental group was significantly less than the control group,and the average number and size of lung metastases of interference of miR-126experimental group was significantly greater than the control group.4. The expression of miR-126in human colon cancer tissue was significantly reduced compared with adjacent normal mucosa. CXCR4and RhoA signal pathway molecules RhoA, RhoGEF, RhoGAP, ROCK, PI3K, PAK1, PKN1were significantly increased in human colon cancer tissue compared with the adjacent normalmucosal tissues (P<0.05), and the expression of CXCR4, RhoA, RhoGEF, ROCK and PI3K has significant correlation with clinical stage, lymph node metastasis (P <0.05).The expression of RhoGAP, PAK1, PKN has nothing to do with clinical and pathological features. Survival analysis showed that positive expression of miR-126in patients with colon cancer survival rate was significantly higher than those with negative expression,and positive expression of CXCR4, RhoA, RhoGEF, ROCK patient survival rate was significantly lower than patients with negative expression (P <0.05), RhoGAP, PAK1, PKN1, PI3K expression and colon cancer survival rate had no significant relationship (P>0.05).Conclusions:1. We build a stable overexpression of miR-126of colon cancer cell line HCT116and a stable interference of miR-126colon cancer cell line SW480successfully.Nude mice tumor formation experiment results confirmed that miR-126can inhibit colon cancer cell proliferation, invasion and metastasis in vivo.2. miR-126can inhibit colon cancer’s invasion and metastasis, and the reason may be through the downregulation of the expression of CXCR4and the activity of RhoA signaling pathway.