Research Report
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World J Gastroenterol. Jun 14, 2014; 20(22): 6906-6911
Published online Jun 14, 2014. doi: 10.3748/wjg.v20.i22.6906
Reduced expression of circulating microRNA-218 in gastric cancer and correlation with tumor invasion and prognosis
Shi-Yong Xin, Xiao-Shan Feng, Li-Qing Zhou, Jun-Jun Sun, Xiao-Le Gao, Guo-Liang Yao
Shi-Yong Xin, Department of Urology, First Affiliated Hospital of Henan University of Science and Technology, Luoyang 471003, Henan Province, China
Xiao-Shan Feng, Department of Surgical Oncology, First Affiliated Hospital of Henan University of Science and Technology, Luoyang 471003, Henan Province, China
Li-Qing Zhou, Department of Rheumatism Immunity Branch, First Affiliated Hospital of Henan University of Science and Technology, Luoyang 471003, Henan Province, China
Jun-Jun Sun, Xiao-Le Gao, Guo-Liang Yao, Department of General Surgery, First Affiliated Hospital of Henan University of Science and Technology, Luoyang 471003, Henan Province, China
Author contributions: Xin SY, Zhou LQ and Gao XL performed the majority of the experiments; Yao GL provided vital reagents and analytical tools and was also involved in revising the manuscript; Feng XS and Sun JJ collected all the human material and provided financial support for this work; Xin SY designed the study and wrote the manuscript.
Supported by A grant from Liaoning Provincial Science and Technology Plan Foundation, No. 2011225013
Correspondence to: Dr. Shi-Yong Xin, Department of Urology, the First Affiliated Hospital of Henan University of Science and Technology, No. 24, Jinghua Road, Luoyang 471003, Henan Province, China. xinshiyong66@163.com
Telephone: +86-379-69823269 Fax: +86-379-69823269
Received: November 19, 2013
Revised: January 21, 2014
Accepted: March 7, 2014
Published online: June 14, 2014
Processing time: 208 Days and 16.9 Hours
Abstract

AIM: To investigate the expression of microRNA-218 (miR-218) in serum from gastric cancer patients and its relationship with clinicopathological characteristics.

METHODS: A total of 68 patients with pathologically diagnosed gastric cancer and 56 healthy individuals were recruited to this study. The expression of miR-218 was detected in the serum of gastric cancer patients and healthy individuals by quantitative real-time polymerase chain reaction. The clinical data were collected and analyzed by statistical software.

RESULTS: miR-218 was reduced significantly in the serum of gastric cancer patients compared to healthy individuals (1.15 ± 0.08 vs 0.37 ± 0.023; P = 0.026). In the gastric cancer group, serum expression of miR-218 was lower in patients with metastasis and poorly differentiated cancer compared with non-metastatic and well-differentiated cancer (0.19 ± 0.011 vs 0.45 ± 0.021, P = 0.031 and 0.21 ± 0.019 vs 0.49 ± 0.021, P = 0.025). Serum miR-218 was found to be significantly associated with gastric cancer metastasis (P = 0.003), tumor T stage (P = 0.018) and tumor grade (P = 0.012). Low serum expression of miR-218 was related to an increase in the stage of gastric cancer. The expression level of miR-218 in the serum was correlated with the 3-year survival. Ninety-seven percent of patients with a high level of miR-218 expression survived for 3 years, while only 54% of those with low miR-218 expression survived.

CONCLUSION: miR-218 is deregulated in gastric cancer patients and is strongly correlated with tumor stage, grade and metastasis. Serum expression of miR-218 may be a prognostic marker.

Keywords: Gastric cancer; microRNA-218; Invasion; Prognosis

Core tip: microRNA-218 (miR-218) has been shown to be a tumor-suppressor miRNA in several cancers. In this study, we investigated the expression of miR-218 in the serum of gastric cancer patients and its relationship with clinicopathological characteristics. miR-218 was deregulated in gastric cancer patients and associated with tumor invasion and prognosis.