Xiaonan Qiu1,2, Haixia Zhu1,3, Sang Liu1,2, Guoquan Tao4, Jing Jin1,2, Haiyan Chu1,2, Meilin Wang1,2, Na Tong1,2, Weida Gong5, Qinghong Zhao6, Fulin Qiang3, Zhengdong Zhang1,2. 1. Department of Environmental Genomics, Jiangsu Key Laboratory of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center For Cancer Personalized Medicine, Nanjing Medical University, Nanjing, China. 2. Department of Genetic Toxicology The Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing, China. 3. Core Laboratory, Nantong Tumor Hospital, Nantong, China. 4. Department of General Surgery, Huai-An First People's Hospital Affiliated to Nanjing Medical University, Huai-An, China. 5. Department of General Surgery, Yixing Cancer Hospital, Yixing, China. 6. Department of General Surgery, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, China.
Abstract
BACKGROUND AND AIM: In our previous study, we demonstrated that four microRNAs (miRNAs) (miR-26a, miR-142-3p, miR-148a, and miR-195) that were downregulated in both plasma and tumor tissues were confirmed to be promising non-invasive diagnostic biomarkers for gastric cancer (GC). METHODS: We used the quantitative reverse transcription polymerase chain reaction to assess the expression levels of the four miRNAs from paraffin-embedded surgical specimens of GC patients. Kaplan-Meier curves and log-rank test were applied to predict the correlation between miRNAs and cumulative overall survival (OS) of patients with GC. Besides, we performed in vitro assays including cell proliferation, migration, invasion and colony formation, and apoptosis. RESULTS: The median of miRNA expression in paraffin-embedded tissues were used as the cutoff value to classify patients into high or low expression groups. Down-regulation of miR-26a and miR-148a was significantly associated with shorter OS of GC patients either in the test set (miR-26a: P = 0.009; miR-148a: P = 0.005) or the validation set (miR-26a: P = 0.011; miR-148a: P = 0.024). When two sets were combined, Cox regression analysis demonstrated that both of miR-26a and miR-148a were independent prognostic factors for predicting OS of patients with GC (miR-26a: HR = 0.76, 95% CI = 0.61-0.94; miR-148a: HR = 0.73, 95% CI = 0.58-0.91). Furthermore, elevated expression of miR-26 significantly suppressed cell proliferation, migration, invasion and colony formation, and induced apoptosis of MGC-803 cells compared with negative control groups (P < 0.05). CONCLUSION: These findings supported miR-26a and miR-148a could serve as potential prognostic biomarkers for GC.
BACKGROUND AND AIM: In our previous study, we demonstrated that four microRNAs (miRNAs) (miR-26a, miR-142-3p, miR-148a, and miR-195) that were downregulated in both plasma and tumor tissues were confirmed to be promising non-invasive diagnostic biomarkers for gastric cancer (GC). METHODS: We used the quantitative reverse transcription polymerase chain reaction to assess the expression levels of the four miRNAs from paraffin-embedded surgical specimens of GC patients. Kaplan-Meier curves and log-rank test were applied to predict the correlation between miRNAs and cumulative overall survival (OS) of patients with GC. Besides, we performed in vitro assays including cell proliferation, migration, invasion and colony formation, and apoptosis. RESULTS: The median of miRNA expression in paraffin-embedded tissues were used as the cutoff value to classify patients into high or low expression groups. Down-regulation of miR-26a and miR-148a was significantly associated with shorter OS of GC patients either in the test set (miR-26a: P = 0.009; miR-148a: P = 0.005) or the validation set (miR-26a: P = 0.011; miR-148a: P = 0.024). When two sets were combined, Cox regression analysis demonstrated that both of miR-26a and miR-148a were independent prognostic factors for predicting OS of patients with GC (miR-26a: HR = 0.76, 95% CI = 0.61-0.94; miR-148a: HR = 0.73, 95% CI = 0.58-0.91). Furthermore, elevated expression of miR-26 significantly suppressed cell proliferation, migration, invasion and colony formation, and induced apoptosis of MGC-803 cells compared with negative control groups (P < 0.05). CONCLUSION: These findings supported miR-26a and miR-148a could serve as potential prognostic biomarkers for GC.