Serum exosomal miR-335-5p serves as a diagnostic biomarker of triple-negative breast cancer / 中华内分泌外科杂志

ABSTRACT

Objective:To investigate the expression and diagnostic value of microRNA-335-5p (miR-335-5p) and Human Vascular endothelial growth factor receptor 1 (VEGFR-1, FLT1) in serum exosomal bodies of patients with triple negative breast cancer (TNBC) .Methods:Gene Expression Omnibus database (GEO) analysis was performed and differentially expressed miRNA in breast cancer tissues was screened. From Jan. 2016 to Nov. 2017, the peripheral blood samples of 56 TNBC patients in People’s Hospital Affiliated to Ningbo University were collected, and the exosomes were isolated and identified. FLT1 was selected as the target gene of miR-335-5p by using bioinformatics analysis. Expression levels of miR-335-5p and FLT1 in serum exosome were detected by qRT-PCR. The relationship between miR-335-5p and clinicopathological parameters of TNBC patients was analyzed. The diagnostic value of miR-335-5p was evaluated by receiver operating characteristic (ROC) , and the survival prognosis of miR-335-5p and FLT1 was analyzed by Kaplan Meier survival curve.Results:The expression of miR-335-5p in the serum exosome of TNBC patients was lower than that of the control group, while the expression of FLT1 in the serum exosome was higher than that of the control group ( P<0.05) . The expression of miR-335-5p was related to tissue grade ( χ2=22.02, P<0.000 1) , degree of differentiation ( χ2=20.67, P<0.000 1) and lymph node metastasis ( χ2=4.667, P=0.030 8) in patients with TNBC ( P<0.05) . The area under ROC diagnosed by miR-335-5p was 0.809 8 (95% CI 0.726 3-0.893 2, P<0.000 1) . Kaplan-Meier survival analysis showed that the overall survival time of patients with low expression of miR-335-5p was significantly shorter than that of patients with high expression of miR-335-5p ( P=0.004 5) . The high expression of its target gene FLT1 was associated with low survival rate ( P=0.048 0) . Conclusion:Serum exosomal miR-335-5p can be used as an important index to predict the prognosis of TNBF and is expected to play a role in diagnosis and treatment of TNBC.