Bo Guo1, Zhenghao Zhao2, Zhen Wang1, Qian Li1, Xiaofei Wang1, Wenjing Wang3, Tusheng Song1, Che Huang1,4,5. 1. Department of cell Biology and Genetics, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, China. 2. The ART Center, Northwest women's and Children's Hospital, Xi'an, China. 3. Department of Hepatobiliary Surgery, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China. 4. Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, Stomatology College of Xi'an Jiaotong University, Xi'an, China. 5. Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education of China, Xi'an, China.
Abstract
BACKGROUND/AIMS: MiR-302b is a major microRNA found in human embryonic stem cells and induced pluripotent stem cells. However, its function in gastric cancer progression remains unclear. METHODS: Quantitative reverse transcription-PCR was performed to detect the expression levels of miR-302b-3p in gastric cancer tissues. MTT, colony formation, and flow cytometer analyses were conducted to explore the function of miR-302b-3p in MKN-45/SGC-7901 cells. A dual-luciferase reporter was used to validate the bioinformatics-predicted target gene of miR-302b-3p. Western blotting and RNA interference were used to evaluate the expression of the AKT signaling pathway and determine the mechanisms underlying miR-302b-3p-induced anti-tumor effects. RESULTS: MiR-302b-3p expression was decreased in gastric cancer tissues and cell lines. Enforced expression of miR-302b suppressed cell proliferation and cell cycle G1-S transition and induced apoptosis. IGF-1R was found to be a direct target of miR-302b-3p, and silencing of IGF-1R resulted in the same biological effects as those induced by miR-302b-3p overexpression in gastric cancer cells. Importantly, both overexpression of miR-302b-3p and silencing of IGF-1R decreased AKT phosphorylation, which modulated AKT related cell cycle regulators (cyclin A2, cyclin D1, CDK2, and CDk6) and apoptotic protein Bax/Bcl-2. CONCLUSION: These results indicate the tumor suppressor role of miR-302b-3p in the pathogenesis of gastric cancer.
BACKGROUND/AIMS: MiR-302b is a major microRNA found in human embryonic stem cells and induced pluripotent stem cells. However, its function in gastric cancer progression remains unclear. METHODS: Quantitative reverse transcription-PCR was performed to detect the expression levels of miR-302b-3p in gastric cancer tissues. MTT, colony formation, and flow cytometer analyses were conducted to explore the function of miR-302b-3p in MKN-45/SGC-7901 cells. A dual-luciferase reporter was used to validate the bioinformatics-predicted target gene of miR-302b-3p. Western blotting and RNA interference were used to evaluate the expression of the AKT signaling pathway and determine the mechanisms underlying miR-302b-3p-induced anti-tumor effects. RESULTS:MiR-302b-3p expression was decreased in gastric cancer tissues and cell lines. Enforced expression of miR-302b suppressed cell proliferation and cell cycle G1-S transition and induced apoptosis. IGF-1R was found to be a direct target of miR-302b-3p, and silencing of IGF-1R resulted in the same biological effects as those induced by miR-302b-3p overexpression in gastric cancer cells. Importantly, both overexpression of miR-302b-3p and silencing of IGF-1R decreased AKT phosphorylation, which modulated AKT related cell cycle regulators (cyclin A2, cyclin D1, CDK2, and CDk6) and apoptotic protein Bax/Bcl-2. CONCLUSION: These results indicate the tumor suppressor role of miR-302b-3p in the pathogenesis of gastric cancer.
Authors: Seong Ho Jeon; Jung Ki Yoo; Chang Min Kim; Eun Su Lim; So Jeong Lee; Ji Min Lee; Seung-Hun Oh; Jin Kyeoung Kim Journal: Cell Death Dis Date: 2018-05-01 Impact factor: 8.469