The Expression And Significance Of MicroRNA-151 And RhoGDIA In The Gastric Cancer

Objective:Gastric cancer is one of the most common cancer worldwide with high incidence and mortality. However, its clinical outcome still remains unsatisfactory.Exploring themolecular mechanism of metastasis might improve its treatment and clinical outcome. MicroRNAs(miRNAs)are a newly discovered class of small noncoding RNA found within the genomes of a wide range of multicellular organisms and negatively regulate gene expression at the posttranscriptional level. Indeed, miRNAs have been shown to play crucial roles in many physiological and pathological processes, including cancer metastasis. To date,a number of microRNAs have been found to be directly involved in the carcinogenesis of gastric cancer. Expression profiles of gastric cancer are closely related with staging, progress and prognosis. Ras homologus oncogenes include RhoA,RhoB and RhoC and so on. The overexpression of RhoC which has been found in many kinds of cancer tissues involed in cancer metastasis. The full name of RhoGDIA is RhoGDP dissociation inhibitor A which is considered to be negative adjustment factor of RhoGTPases.It combines with GDP forms of Rho, occluding in the cytoplasm, stopping its membrane action, thus inhibiting GTP binding activity.The objectives of this study are to investigate the expression of miR-151 and RhoGDIa in gastric cancer tissues (GCTs) and normal adjacent tumor tissues(NATs) to observe the variability of the Protein expression quantity of RhoGDIa CDC42 and RhoA under the impact of miR-151 in MGC.To discover the relation between the expression of miR-151 and gastric metastasis and to develop a new road to research the progression of stomach cancer.Methods:32 gastric cancer specimens including gastric cancer tissues and normal adjacent tumor tissues were collected from operations in the 2nd Xiangya hospital of Central South University from June 2010 to December 2010. These specimens were investigated using real time PCR to detect the expression of miR-151 and RhoGDIa in gastric cancer tissues(GCTs) and normal adjacent tumor tissues(NATs). Turn to transfected into MGC cell were transfected with the mature body of miR-151 and the inhibitors of miR-151 and to observe the Protein expression quantity Of RhoGDIa CDC42 and RhoA by Western blot.Results:The results showed that the expression of miRNA-151-5p in gastric cancer tissues was significantly higher than that in normal adjacent tumor tissues.(P<0.05)The expression level of miRNA-151-3p in gastric cancer tissues was similar with that in normal adjacent tumor tissues. (P>0.05)The expression of RhoGDIA in gastric cancer tissues was significantly lower than that in normal adjacent tumor tissues.(P<0.05) The expression level of miRNA-151-5p in gastric cancer tissues was not significantly correlated with the age the gender or the degree of tumor penetration embellish depth.(P>0.05)The expression level of miRNA-151-5p and RhoGDIA in gastric cancer tissues was significantly correlated with Grade of Differentiation and clinical stages in direct rate.(P<0.05)With regards to MGC cell transfection with the mature body of miR-151-5p, the protein expression quantity Of RhoGDIA is lower than that of reference. The protein expression quantity Of CDC42 and RhoA was higher than that of reference.Turn to transfected into MGC803 cell with the inhibitors of miR-151-5p showed contrary results.MGC803 cell transfected with miR-151-5p, demonstrated no significant change in the protein expression quantity Of RhoGDIa CDC42 and RhoA.Conclusion:1 There is a high level of expression of miRNA-151-5p in gastric cancer tissues.2 The expression level of miRNA-151-5p in gastric cancer tissues was no significantly correlated with the age the gender and the degreen of tumor penetration embellish depth. The expression level of miRNA-151-5p in gastric cancer tissues was significantly correlated with Grade of Differentiation and clinical stages in direct rate.3 RhoGDIa is the target genes of miRNA-151-5p.