Evaluation of miR-29c, miR-124, miR-135a and miR-148a in predicting lymph node metastasis and tumor stage of gastric cancer.

MicroRNAs (miRNAs) are small noncoding RNA that have diverse functions in different biological process. The aim of this study was to evaluate the predictive ability of miR-29c, miR-124, miR-135a and miR-148a for lymph node metastasis (LNM) and tumor stage in gastric cancer. The expression of these miRNAs was detected and quantitated in gastric cancer tissues and in adjacent normal tissues from 60 patients by quantitative real-time reverse transcription-polymerase chain reaction. CT imaging and clinicopathologic characteristics of these patients were performed. The result of this study was that these miRNAs were down-regulated in gastric cancer tissues; The low expression of miR-124 and miR-135a in LNM group and tumor III-IV stages (P < 0.01) presented the potential correlation with LNM and tumor stage; The two miRNAs were highly correlated with r = 0.730. Receiver operating characteristic curve analysis showed that miR-124 had better predictive ability to identify LNM and tumor stage. It could discriminate non-LNM from LNM with 80.0% sensitivity and 80.0% specificity and discriminate tumor Ι-II stages from tumor III-IV stages with 71.9% sensitivity and 75.0% specificity at the best cut-off value of 0.0125. Compared with CT imaging, miR-124 had similar specificity (0.800 versus 0.900, P = 0.508) but higher sensitivity (0.800 versus 0.500, P = 0.022) for lymph node assessment; Combined of miR-124 and CT imaging, The sensitivity and specificity of assessing LNM were raised to 83.3% and 90.0% respectively. Taken together, miR-124 may be a predictor for LNM and tumor stage in gastric cancer.