Expression Of MiR-200a And Its Target Gene PTEN In Colorectal Carcinoma And Their Significance

Objective To investigate the expression level of mi R-200 a and PTEN in colorectal carcinoma(CRC) and their relationships with clinicopathologic features. To investigate the correlation between mi R-200 a and PTEN in CRC.Methods 1. In situ hybridization(ISH) for mi R-200 a was performed in 107 colorectal carcinoma and adjacent mucosa,then illustrated its relationship with clinicopathologic factors of CRC. 2. Bioinformatics tools and luciferase reporter assay were used to analyze and predict the potential target of mi R-200 a is PTEN. 3. Immunohistochemistry(IHC) for PTEN was performed in 107 colorectal carcinoma and adjacent mucosa, then illustrated its relationship with clinicopathologic factors of CRC.Results 1. The ISH data showed that the positive expression rate of the mi R-200 a in CRC(65.4%)was higher than those in normal colorectal mucosa(10.3%)(P<0.001). The expression of mi R-200 a was positively correlated with the degree of tumor differentiation,it is lower in the poorly differentiated CRC than the highly and moderately differentiated CRC(P<0.001).2. Bioinformatics tools and luciferase reporter assay demonstrated PTEN as the target of mi R-200 a. 3. The IHC data showed that the positive expression rate of PTEN in CRC(32.7%)was lower than those in normal colorectal mucosa(91.6%)(P<0.001). The expression of mi R-200 a had a close negative correlation to that of PTEN in CRC(r=ï¹£0.541,P<0.001).Conclusions 1. The expression level of mi R-200 a is up-regulated in CRC,it is correlated with the degree of tumor differentiation, and mi R-200 a may play an important role in the occurrence and development of CRC. 2. Overexpression of mi R-200 a might be associated with the development of CRC by targeting PTEN. 3. The expression of PTEN is down-regulated in CRC,mi R-200 a and PTEN could be the indicators in the diagnosis and prognosis of colorectal carcinoma.