title: MicroRNA-124 inhibits cell proliferation and migration by regulating SNAI2 in breast cancer.
abstract: MicroRNA (miRNA) is a type of endogenous non‑coding RNA implicated in various cellular processes. Studies have shown that miR-124 is involved in the malignant progression of cancer, but little is known concerning its potential role in breast cancer. Therefore, the purpose of this study was to conduct a functional analysis of miR-124 in breast cancer, and to identify its target genes in this disease. To this end, we used quantitative real-time PCR to examine the expression level of miR-124 in breast cancer tissue specimens and cell lines. To study the functional significance of miR-124, we overexpressed miR-124 with miR-124 mimics and observed breast cancer cell proliferation, colony formation, migration, and invasion abilities by in vitro cell culture experiments. Target prediction algorithms and luciferase reporter gene assays were used to identify the target genes of miR-124. We also knocked down miR-124 targets using short hairpin RNA (shRNA) constructs, and observed associated breast cancer cell characteristics by in vitro cell culture experiments. We found that miR-124 expression significantly decreased in breast cancer tissues and cells compared to normal tissues and cells. In addition, cell proliferation, colony formation, migration, and invasion were decreased after overexpression of miR-124 in breast cancer cells. Furthermore, we used several algorithms to identify the snail family zinc finger 2 (SNAI2) as a potential target gene of miR-124. The protein expression level and luciferase activity of the 3'-untranslated region of SNAI2 were significantly decreased in breast cancer cells transfected with miR-124 mimics. Cell proliferation, colony formation, migration, and invasion were also decreased after knockdown of SNAI2 by shRNA. In conclusion, our data suggest that miR-124 expression is decreased in breast cancer and plays an important role as a tumor suppressor gene by targeting SNAI2. These findings may reveal novel perspectives for clinical treatments against breast cancer.
authors.affiliation: School of Medicine, Southeast University, Nanjing, Jiangsu 210009, P.R. China.
authors.forename: Shanmei
authors.initials: S
authors.lastname: Du
authors.affiliation: Affiliated Hospital of Taishan Medical College, Tai'an, Shandong 271000, P.R. China.
authors.forename: Helou
authors.initials: H
authors.lastname: Li
authors.affiliation: School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, P.R. China.
authors.forename: Xiaochun
authors.initials: X
authors.lastname: Sun
authors.affiliation: The First Hospital of Zibo, Zibo, Shandong 255200, P.R. China.
authors.forename: Dongsheng
authors.initials: D
authors.lastname: Li
authors.affiliation: Affiliated Hospital of Taishan Medical College, Tai'an, Shandong 271000, P.R. China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Yang
authors.affiliation: School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, P.R. China.
authors.forename: Zehua
authors.initials: Z
authors.lastname: Tao
authors.affiliation: Zibo Vocational Institute, Zibo, Shandong 255314, P.R. China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Li
authors.affiliation: The First Hospital of Zibo, Zibo, Shandong 255200, P.R. China.
authors.forename: Kui
authors.initials: K
authors.lastname: Liu
mesh_terms: D020413:3' Untranslated Regions; D001483:Base Sequence; D001665:Binding Sites; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D002465:Cell Movement; D049109:Cell Proliferation; D005260:Female; D006801:Humans; D061986:MCF-7 Cells; D035683:MicroRNAs / Q000502:physiology*; D009361:Neoplasm Invasiveness; D034622:RNA Interference; D000071250:Snail Family Transcription Factors / Q000235:genetics* / Q000378:metabolism
chemical_list: D020413:3' Untranslated Regions; C509207:MIRN124 microRNA, human; D035683:MicroRNAs; C000604408:SNAI2 protein, human; D000071250:Snail Family Transcription Factors