Clinical Significance Of Combined Detection Of Serum Exosomal MiR-21 And MiR-92a In Patients With Colorectal Cancer

Part I Clinical significance of exosomal miR-21.miR-92a expression in plasma of patients with colorectal carcinoma.ObjiectiveThis study is to explore the diagnostic value of the combined dection of exosomal miR-21and miR-92a in plasma as a promising noninvasive screening tool for colorectal cancer.Method1.Exosomes derived from the serum of CRC,colorectal adenoma and health controls were extracted through ultracentrifugation method and its size were observed by using transmission electron microscope(TEM).2.Real-time quantitative polymerase chain reaction(RT-PCR)was used to detect the expression levels of serum exosomal miR-21,miR-92a in 70 CRC patients,45 colorectal adenoma patients and 60 health controls.ROC curves were applied to identify the area under the curve and compare the diagnostic efficacy with the traditional tumor biomarkers such as CEA.3.All data in the experiment was presented as average ± standard deviation(x±s).The data were test by Independent-Sample T Test.All the statistical analysis were performed using SPSS 21.0 and P values less than 0.05 were considered to be statistically significant.Results1.Exosomes from the serum of CRC,colorectal adenoma and health controls were isolated.Exosomes are shaped as spherical vesicles,with the diameter from 40-100 nm.There was no significant difference in the size of exosomes derived from different groups.2.The expression level of exosomal miR-21and miR-92a in the serum of patients with CRC and colorectal adenoma was significantly higher than that of health controls.3.Detection of serum exosomal miR-21 and miR-92a in the area under the receiver-operating characteristics(ROC)curve(AUC)were 0.86 and 0.87 for the diagnosis of colorectal cancer,respectively;while were 0.82 and 0.82 for the diagnosis of advanced adenoma,respectively.Combined detection of serum exosomal miR-21 and miR-92a in the area under AUC was 0.93 for the diagnosis of colorectal cancer and 0.87 for the diagnosis of advanced adenoma.4.The diagnostic efficacy of combined ROC of exosomal miR-21 and miR-92a was higher than that of traditional tumor biomarkers CEA.ConclusionsExosomes were rapidly and conveniently isolated from the serum of corectal cancer patients by using ultracentrifugation method.Serum exosomal miR-21 and miR-92a were a potential non-invasive biomarker for CRC.Moreover,combined dection of Serum exosomal miR-21 and miR-92a may improved the sensitivity and specifity in diagnosis CRC.Part ? Relationship between serum exosomal miR-21?miR-92a expression and clinicopathological features and prognosis in patients with colorectal carcinoma.Objiective:Exosomal miR-21 and miR-92a have been reported to be aberrant expression in CRC in the first part of our studies,but their relationship with clinicopathological features and prognosis in CRC is poorly understood.So this part aimed to elucidate the application value of miR-21 and miR-92a for diagnosis and prognosis in CRC.Method:The exosomal miR-21 and miR-92a expression levels in serum from 55 CRC patients were measured by RT-PCR.The correlation between the expression of serum exosomal miRNA and clinical pathological parameters was analyzed by Spearman rank correlation coefficient.ResultsThe expression level of serum exosomal miR-21 was significantly related to the presence of liver metastasis and exosomal miR-92a was correlated with advanced tumor classification,vessel invasion and positive lymph node status.But not with the other clinical pathological parameters(gender,age,tumor location,tumor histological type and tumor differentiation).ConclusionsOur fingdings indicated that the expression of exosomal miR-21 and miR-92a could reflect the malignancy of CRC in liver metastasis,TNM stage and seems uniquely promising as plasma biomarkers for diagnosis and prognosis of CRC.