title: MicroRNA miR-30 family regulates non-attachment growth of breast cancer cells.
abstract: BACKGROUND
  A subset of breast cancer cells displays increased ability to self-renew and reproduce breast cancer heterogeneity. The characterization of these so-called putative breast tumor-initiating cells (BT-ICs) may open the road for novel therapeutic strategies. As microRNAs (miRNAs) control developmental programs in stem cells, BT-ICs may also rely on specific miRNA profiles for their sustained activity. To explore the notion that miRNAs may have a role in sustaining BT-ICs, we performed a comprehensive profiling of miRNA expression in a model of putative BT-ICs enriched by non-attachment growth conditions.
  
  
  RESULTS
  We found breast cancer cells grown under non-attachment conditions display a unique pattern of miRNA expression, highlighted by a marked low expression of miR-30 family members relative to parental cells. We further show that miR-30a regulates non-attachment growth. A target screening revealed that miR-30 family redundantly modulates the expression of apoptosis and proliferation-related genes. At least one of these targets, the anti-apoptotic protein AVEN, was able to partially revert the effect of miR-30a overexpression. Finally, overexpression of miR-30a in vivo was associated with reduced breast tumor progression.
  
  
  CONCLUSIONS
  miR30-family regulates the growth of breast cancer cells in non-attachment conditions. This is the first analysis of target prediction in a whole family of microRNAs potentially involved in survival of putative BT-ICs.
authors: Epigenetics Group, International Agency for Research on Cancer (IARC), 150 rue Albert-Thomas, Lyon, 69008, France.
authors: Maria
authors: M
authors: Ouzounova
authors: Tri
authors: T
authors: Vuong
authors: Pierre-Benoit
authors: PB
authors: Ancey
authors: Mylène
authors: M
authors: Ferrand
authors: Geoffroy
authors: G
authors: Durand
authors: Florence
authors: F
authors: Le-Calvez Kelm
authors: Carlo
authors: C
authors: Croce
authors: Chantal
authors: C
authors: Matar
authors: Zdenko
authors: Z
authors: Herceg
authors: Hector
authors: H
authors: Hernandez-Vargas
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism; D000818:Animals; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism; D001943:Breast Neoplasms / Q000235:genetics / Q000473:pathology*; D049109:Cell Proliferation; D002470:Cell Survival; D002471:Cell Transformation, Neoplastic; D005260:Female; D020869:Gene Expression Profiling; D061986:MCF-7 Cells; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D035683:MicroRNAs / Q000235:genetics*; D014411:Neoplastic Stem Cells / Q000378:metabolism / Q000473:pathology; D015203:Reproducibility of Results
chemical_list: C412506:AVEN protein, human; D048868:Adaptor Proteins, Signal Transducing; D051017:Apoptosis Regulatory Proteins; C546086:MIRN30b microRNA, human; D008565:Membrane Proteins; D035683:MicroRNAs