Significance of human plasma and feces microRNA-92a-1 expression level in colorectal tumor screening

Abstract

Objective To explore the feasibility and clinical significance of combined detection of human plasma and feces expression level of microRNA-92a-1 (miRNA-92a-1) as colorectal tumour screening marker.Methods From August to October in 2011,the feces and plasma samples of 60 colorectal cancer (CRC) patients,23 colorectal adenoma (CRA) patients and 30 healthy controls were collected.The expression level of miRNA-92a-1 was determined by quantitative reverse transcription-polymerase chain reaction.Mann-Whitney's U test was applied for the difference test between groups.Then,according to the receiver operating characteristic (ROC) curve analysis the cut-off point was determined and the sensitivity and specificity were analyzed.Results Compared with healthy controls,the expressions of miRNA-92a-1 in plasma of CRC and CRA patients increased (U=288.5 and 151.0,both P＜0.01).Compared with healthy controls,the expression of miRNA-92a-1 in feces of CRC patients increased (U=627.5,P=0.0199).According to ROC curve analysis,when the cut-off point was ＞1.22,the sensitivities of plasma miRNA-92a-1 in CRC patients and CRA patients were 85.0％ (51/60) and 73.9％ (17/23) respectively.The specificity of healthy controls was 76.7％ (23/30).When the cut-off point was ＞1.14,the sensitivities of feces miRNA-92a-1 in CRC patients and CRA patients were 31.7％(19/60) and 26.1％(6/23) respectively.The specificity of healthy controls was 90.0 ％ (27/30).Combined the detection results of plasma and feces,the sensitivities of miRNA-92a-1 in CRC patients and CRA patients was 88.3％ (53/60) and 82.6％ (19/23) respectively.The specificity in healthy controls was 73.3％ (22/30).The sensitivity was higher than that of single sample testing.Conclusions The sensitivity and specificity are high in the combined detection of plasma and feces miRNA-92a-1 expression level in CRC patients and CRA patients,miRNA-92a-1 may be a potential CRC screening marker. Key words: microRNAs; Colorectal neoplasms; Real-time polymerase chain reaction; Plasma; Feces; Mass screening