Title:Up-regulated Circulating miR-106a by DNA Methylation Promised a Potential Diagnostic and Prognostic Marker for Gastric Cancer
VOLUME: 16 ISSUE: 9
Author(s):Renshun Yuan, Gang Wang, Zhihua Xu, Hong Zhao, Huabin Chen, Ye Han, Bin Wang, Jin Zhou, Hao Hu, Zhaoji Guo, Hugang Shen and Xiaofeng Xue
Affiliation:Department of General Surgery, Kunshan Hospital of Traditional Chinese Medicine, Kunshan, 215000, China., Department of General Surgery, the First Affiliated Hospital of Soochow University, Suzhou, 215006, China.
Keywords:Gastric cancer, miR-106a, methylation regulation, oncogenic miRNA, TNM stage, lymph node metastasis.
Abstract:Previous studies suggested that abnormal miRNA expression was a significant
characteristic of malignant tumors. We aimed to explore the role of miR-106a as the potential
diagnostic and prognostic biomarker in gastric cancer (GC). Firstly, the expression level of
miR-106a was detected by qPCR in 28 pairs of GC cancer tissues and adjacent tissues, 48 pairs
of plasma samples before and after operation from GC patients, and 22 plasma samples from
healthy controls. It had revealed that the level of miR-106a in tumor tissues (2.700±2.565) was
significantly higher compared to adjacent tissues (1.321±0.904) (p<0.05). Besides, the
expression level of miR-106a in plasma of GC (9.479±5.595) was significantly up-regulated
compared with healthy controls (2.594±2.329) (p<0.05), while a remarkable decline of miR-
106a expression was observed in plasma of GC patients after gastrectomy. Further statistic data
showed high miR-106a expression was closely related to the degree of lymphatic metastasis
and TNM staging of GC. We also applied ROC curve in order to evaluate miR-106a as a
diagnostic marker for GC patients. As a result, the sensitivity and specificity were 60.4%, 68.2% in tissue samples and
72.9%, 63.6% in plasma samples, respectively. At last, we explored the methylation status of miR-106a promoter in 28
paired GC tissues through methylation-specific PCR (MSP), the result showed that the methylation rate was 53.6% in
cancer tissues and 85.7% in adjacent tissues. Moreover, the result indicated that promoter hypomethylation of miR-
106a is related to its high expression. Our research indicated that miR-106a might serve as a potential prognostic
indicator in progressive GC and up-regulated circulating miR-106a by promoter hypomethylation, might be proposed
as a candidate diagnostic and prognostic indicator for GC.