The Experimental Research On The Gene Regulated By MiRNA-21in Xenogenic Human Colon Cancer In Nude Mice

Objective Research the expression of gene regulated by microRNA-21in nude mouse model of colon cancer. The relationship of these data was analyzed to discuss their different functions in multiplication and metastasis of colon cancer.Methods A BABL/c nude mouse model of colon cancer was established by using tumor cell HCT-116. When tne volume of the transplanted tumor reach about60mm3,the mice was divided into three groups randomly:experimental group(internal transfection plasmid miRZip21group), negative control group(internal transfection plasmid miRZip000group) and blank control group. To observe the growth information of the xenogenic tumor and the observe time is six weeks. The mRNA transcription levels of TIMP3,PCDH17, RECK,BMPR Ⅱ were determined by real-time quantitative PCR using fluorescence and the proteins of TIMP3,PCDH17, RECK,BMPR Ⅱ were tested by immunohistochemistry staining.Results The volumes of mice colon tumors in the three groups were likely before the11th day (p>0.05). While the size of experimental group was significantly smaller than other two groups after13th day(p<0.05).The mRNA transcription levels of TIMP3,PCDH17,RECK,BMPRⅡin xenogenic tumor tissues have no significant difference between blank and negative control group(p>0.05). The mRNA transcription levels of TIMP3、PCDH17、RECK in experimental group upregulated to2.8fold、3.5fold,、3.8fold compaired with the blank control group(p<0.05). The mRNA transcription level of BMPRⅡin experimental group downregulated to0.5fold compaired with the blank control group(p<0.05).The protein expressions of TIMP3,PCDH17,RECK,BMPRⅡhave no significant difference between blank and negative control group (p<0.05). The protein expressions of TIMP3、PCDH17、RECK in experimental group upregulated to about2fold compaired with the blank control group(p<0.05). The protein expression of BMPRⅡin experimental group downregulated to0.5fold compaired with the blank control group(p<0.05).Positive correlation of mRNA transcription levels of TIMP3with BMPRⅡ were detected in experimental group(P<0.05).However the mRNA transcription levels of TIMP3with PCDH17or RECK have no correlations,so does PCDH17with RECK. The protein expressions of TIMP3,PCDH17,RECK,BMPRⅡhave no correlations.Conclusion Firstly, partly subcutaneous injections colon carcinoma cell can set up nude mouse model of allotopia colon cancer successfully. Secondly, through the inhibitor of micro RNA-21can slower the growth rate of xenogenic tumor in nude mouse, to explain that there was correlative gene to tumor hyperplasia from the target gene of microRNA-21.Thirdly,through reduction of the expression of microRNA-21, the mRNA transcription and protein levels of TIMP3、PCDH17、RECK were upregulated and the mRNA transcription and protein level of BMPRⅡ was downregulated. It can suppress the growth rate of colon cancer. TIMP3,PCDH17, RECK,BMPRⅡ were the gene targets of microRNA-21.They played different efferts in the orgion and development of colon cancer,and will become an important methord in colon cancer treatment.Fourthly, the mRNA transcription levels of TIMP3with BMPRⅡhave positive correlation.It maybe has some kind of contact in control network.But the specific mechanism is not clear,still need further research.