title: Downregulated miR-31 level associates with poor prognosis of gastric cancer and its restoration suppresses tumor cell malignant phenotypes by inhibiting E2F2.
abstract: The miRNA microarray analysis showed that miR-31 was reduced in gastric cancer. This study further assessed miR-31 expression and role of miR-31 in gastric cancer tissues and cell lines. The data showed that miR-31 expression was down-regulated in 40 cases of gastric cancer tissues compared to the adjacent normal tissues, and low expression of miR-31 was associated with poor tumor differentiation, lymph node metastasis, advanced T stage and worse overall survival of gastric cancer patients. Ectopic expression of miR-31 reduced tumor cell viability, enhanced apoptosis, arrested tumor cells at G1 transition, and reduced tumor cell migration and invasion in SGC-7901 and MGC-803 gastric cell lines in vitro. Enforced expression of miR-31 also inhibited growth of engrafted tumors in vivo. Luciferase reporter assays and western blot revealed that E2F2 is the direct target of miR-31. E2F2 expression was upregulated in gastric cancer tissues, and inversely associated with miR-31 levels, while knockdown of E2F2 expression mimicked miR-31 anti-tumor activity in gastric cancer cells, but the ectopic expression of E2F2 rescued the miR-31-mediated inhibition in gastric cell lines. Taken together, these results demonstrated that miR-31 acts as a crucial tumor suppressive activity by inhibiting E2F2s expression. Thus, miR-31 might be a candidate therapeutic target for gastric cancer patients.
authors.affiliation: Department of Pathogenobiology, The Key Laboratory of Zoonosis, Chinese Ministry of Education, College of Basic Medicine, Jilin University, Changchun, Jilin, China.
authors.forename: Huaidong
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Pathogenobiology, The Key Laboratory of Zoonosis, Chinese Ministry of Education, College of Basic Medicine, Jilin University, Changchun, Jilin, China.
authors.forename: Xiaotian
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Pathogenobiology, The Key Laboratory of Zoonosis, Chinese Ministry of Education, College of Basic Medicine, Jilin University, Changchun, Jilin, China.
authors.forename: Yuxin
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Pathogenobiology, The Key Laboratory of Zoonosis, Chinese Ministry of Education, College of Basic Medicine, Jilin University, Changchun, Jilin, China.
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Ni
authors.affiliation: Department of Pathogenobiology, The Key Laboratory of Zoonosis, Chinese Ministry of Education, College of Basic Medicine, Jilin University, Changchun, Jilin, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Lin
authors.affiliation: Department of Pathogenobiology, The Key Laboratory of Zoonosis, Chinese Ministry of Education, College of Basic Medicine, Jilin University, Changchun, Jilin, China.
authors.forename: Zipeng
authors.initials: Z
authors.lastname: Duan
authors.affiliation: Department of Pathogenobiology, The Key Laboratory of Zoonosis, Chinese Ministry of Education, College of Basic Medicine, Jilin University, Changchun, Jilin, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Shi
authors.affiliation: Department of Pathogenobiology, The Key Laboratory of Zoonosis, Chinese Ministry of Education, College of Basic Medicine, Jilin University, Changchun, Jilin, China.|The Key Laboratory for Bionics Engineering, Ministry of Education, Jilin University, Changchun, Jilin, China.
authors.forename: Guoqing
authors.initials: G
authors.lastname: Wang
authors.affiliation: Department of Pathogenobiology, The Key Laboratory of Zoonosis, Chinese Ministry of Education, College of Basic Medicine, Jilin University, Changchun, Jilin, China.|The Key Laboratory for Bionics Engineering, Ministry of Education, Jilin University, Changchun, Jilin, China.
authors.forename: Fan
authors.initials: F
authors.lastname: Li
mesh_terms: D020413:3' Untranslated Regions / Q000235:genetics; D000818:Animals; D017209:Apoptosis / Q000235:genetics; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000235:genetics; D015536:Down-Regulation; D050703:E2F2 Transcription Factor / Q000235:genetics* / Q000378:metabolism; D005260:Female; D059585:G1 Phase Cell Cycle Checkpoints / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D035683:MicroRNAs / Q000235:genetics*; D008875:Middle Aged; D010641:Phenotype; D011379:Prognosis; D034622:RNA Interference; D013274:Stomach Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D014183:Transplantation, Heterologous
chemical_list: D020413:3' Untranslated Regions; D050703:E2F2 Transcription Factor; C493761:E2F2 protein, human; C534612:MIRN31 microRNA, human; D035683:MicroRNAs
keywords: E2F2; biomarker; gastric cancer; miR-31; miRNA