title: Decreased miR-124-3p Expression Prompted Breast Cancer Cell Progression Mainly by Targeting Beclin-1.
abstract: BACKGROUND
  Recent findings have revealed that abnormal expression of microRNAs (miRNA, miR) contributes to the malignancies of various cancers. Here, we report a novel miRNA that regulates the expression of Beclin-1 in breast cancer cells.
  
  
  METHODS
  The expression of miR-124-3p and Beclin-1 was identified in breast cancer tissues and breast cancer cell lines. To explore whether Beclin-1 was the target gene of miR-124-3p, luciferase reporter assay was applied. MIR-124-3p was overexpressed or inhibited with the corresponding mimics or inhibitors. The expression of autophagy-related proteins including Beclin-1 and LC3II were explored by western blot and quantitative real-time PCR.
  
  
  RESULTS
  We first demonstrated that miR-124-3p was decreased in breast cancer tissues and breast cancer cells lines. Furthermore, we validated that miR-124-3p could negatively regulate the expression of Beclin-1. Increased miR-124-3p significantly decreased the expression of Beclin-1 and LC3I. Further study showed that overexpres- sion of miR-124-3p could partially reverse 4-hydroxytamoxifen (4-OHT)-induced autophagy in breast cancer cells.
  
  
  CONCLUSIONS
  Decreased miR-124-3p expression prompted breast cancer cell progression mainly by enhancing the expression of autophagy related protein, Beclin-1.
authors.forename: Fengfeng
authors.initials: F
authors.lastname: Zhang
authors.forename: Binbin
authors.initials: B
authors.lastname: Wang
authors.forename: Houlong
authors.initials: H
authors.lastname: Long
authors.forename: Jingkui
authors.initials: J
authors.lastname: Yu
authors.forename: Feng
authors.initials: F
authors.lastname: Li
authors.forename: Haitao
authors.initials: H
authors.lastname: Hou
authors.forename: Qifeng
authors.initials: Q
authors.lastname: Yang
mesh_terms: D051017:Apoptosis Regulatory Proteins / Q000235:genetics / Q000378:metabolism*; D001343:Autophagy / Q000187:drug effects; D000071186:Beclin-1; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D002470:Cell Survival / Q000187:drug effects; D015536:Down-Regulation; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D061986:MCF-7 Cells; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D020845:Selective Estrogen Receptor Modulators / Q000494:pharmacology; D015398:Signal Transduction; D013629:Tamoxifen / Q000031:analogs & derivatives / Q000494:pharmacology; D014162:Transfection
chemical_list: D051017:Apoptosis Regulatory Proteins; C491997:BECN1 protein, human; D000071186:Beclin-1; C509207:MIRN124 microRNA, human; D008565:Membrane Proteins; D035683:MicroRNAs; D020845:Selective Estrogen Receptor Modulators; D013629:Tamoxifen; C016601:afimoxifene