The abnormal expression of microRNA-25 in the serum of gastric cancer patients and its clinical signification

Abstract

Objective To investigate the abnormal expression of microRNA (miRNA)-25 in the serum of gastric cancer patients and its clinical significance. Methods In Xijing Hospital of Digestive Diseases,Fourth Military Medical University,86 gastric cancer patients with operation and completed follow-up data,70 gastric adenoma patients and 80 healthy controls were selected as study objects.Total RNA was isolated from the serum. After the stable and sensitive miRNA-25 absolute quantity detection method established,the serum levels of miRNA-25 in gastric carcinoma patients,gastric adenoma patients and healthy controls were tested according to this method. The expression differences of miRNA-25 in the serum of patients with gastric cancer and gastric adenoma and healthy controls were analyzed with statistic analysis,and the correlation between miRNA-25 expression level and clinic pathological features of gastric cancer was also analyzed. Results The expression level of miRNA-25 in the serum of gastric cancer patients (135. 6 fmol/μg total RNA) was significantly higher than that of gastric adenoma patients (67. 7 fmol/μg total RNA) and healthy controls (62. 2 fmol/μg total RNA)(P＜0. 01). The receiver operating characterisstic curve of miRNA-25 indicated that serum miRNA-25 with good specificity and sensitivity in gastric cancer diagnosis (AUC=0. 827). The serum level of miRNA-25 in gastric cancer patients with lymph node metastasis [(148. 3±10. 2) fmol/μg total RNA] or clinicopathological stage Ⅲ /Ⅳ patients [(146. 7±9.5) fmol/μg total RNA] was significantly higher than that of gastric cancer patients without lymph node metastasis [(120. 3±10. 1)fmol/μg total RNA] or clinicopathological stage Ⅰ/Ⅱpatients [(119. 4±12. 2) fmol/μg total RNA] (P＜0.05). The correlation statistical analysis result indicated that there was no significant difference in survival period between serum miRNA-25 highly expressed and lowly expressed gastric cancer patients (P＞0. 05).Conclusion Serum miRNA-25 testing maybe helpful in diagnosis and prognosis of gastric cancer. Key words: microRNAs; Tumor markers,biological; Stomach neoplasms; Sensitivity and Specificity; Prognosis