title: Suppression of cell migration is promoted by miR-944 through targeting of SIAH1 and PTP4A1 in breast cancer cells.
abstract: Aberrant expression of microRNAs has been associated with migration of tumor cells. In this study, we aimed to investigate the biological significance of miR-944 whose function is unknown in breast cancer.
  
  
  
  MiR-944 expression in breast cancer cells and tumors was evaluated by Taqman qRT-PCR assays. Transcriptional profiling of MDA-MB-231 cells expressing miR-944 was performed using DNA microarrays. Cell viability, migration and invasion were assessed by MTT, scratch/wound-healing and transwell chamber assays, respectively. The luciferase reporter assay was used to evaluate targeting of SIAH1, PTP4A1 and PRKCA genes by miR-944. SIAH1 protein levels were measured by Western blot. Silencing of SIAH1 gene was performed by RNA interference using shRNAs.
  
  
  
  Our data showed that miR-944 expression was severely repressed in clinical specimens and breast cancer cell lines. Suppression of miR-944 levels was independent of hormonal status and metastatic potential of breast cancer cells. Gain-of-function analysis indicated that miR-944 altered the actin cytoskeleton dynamics and impaired cell migration and invasion. Genome-wide transcriptional profiling of MDA-MB-231 cells that ectopically express miR-944 showed that 15 genes involved in migration were significantly repressed. Notably, luciferase reporter assays confirmed the ability of miR-944 to bind the 3´UTR of SIAH1 and PTP4A1 genes, but not PRKCA gene. Congruently, an inverse correlation between miR-944 and SIAH1 protein expression was found in breast cancer cells. Moreover, SIAH1 was upregulated in 75 % of miR-944-deficient breast tumors. Finally, SIAH1 gene silencing by RNA interference significantly impaired cell migration of breast cancer cells.
  
  
  
  Our results pointed out that miR-944 is a novel upstream negative regulator of SIAH1 and PTP4A1 genes and provided for the first time evidence for its functional role in migration and invasion of breast cancer cells. They also suggest that miR-944 restoration may represent a potential strategy for breast cancer therapy.
authors.affiliation: Universidad Autónoma de la Ciudad de México, Posgrado en Ciencias Genómicas, Ciudad de México, México.
authors.forename: Ali
authors.initials: A
authors.lastname: Flores-Pérez
authors.affiliation: Programa en Biomedicina Molecular y Red de Biotecnología, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Ciudad de México, México.
authors.forename: Laurence A
authors.initials: LA
authors.lastname: Marchat
authors.affiliation: Instituto de Enfermedades de la Mama, FUCAM, Ciudad de México, México.
authors.forename: Sergio
authors.initials: S
authors.lastname: Rodríguez-Cuevas
authors.affiliation: Instituto de Enfermedades de la Mama, FUCAM, Ciudad de México, México.
authors.forename: Verónica Piña
authors.initials: VP
authors.lastname: Bautista
authors.affiliation: Universidad Autónoma de Nuevo León, CIDICS, Ciudad de México, México.
authors.forename: Lizeth
authors.initials: L
authors.lastname: Fuentes-Mera
authors.affiliation: Universidad Autónoma de la Ciudad de México, Posgrado en Ciencias Genómicas, Ciudad de México, México.
authors.forename: Diana
authors.initials: D
authors.lastname: Romero-Zamora
authors.affiliation: Universidad Autónoma de la Ciudad de México, Posgrado en Ciencias Genómicas, Ciudad de México, México.
authors.forename: Anabel
authors.initials: A
authors.lastname: Maciel-Dominguez
authors.affiliation: Universidad Autónoma de la Ciudad de México, Posgrado en Ciencias Genómicas, Ciudad de México, México.
authors.forename: Olga Hernández
authors.initials: OH
authors.lastname: de la Cruz
authors.affiliation: Universidad Autónoma de la Ciudad de México, Posgrado en Ciencias Genómicas, Ciudad de México, México.
authors.forename: Miguel
authors.initials: M
authors.lastname: Fonseca-Sánchez
authors.affiliation: Laboratorio de Medicina Translacional, Instituto Nacional de Cancerología, Ciudad de México, México.
authors.forename: Erika
authors.initials: E
authors.lastname: Ruíz-García
authors.affiliation: Laboratorio de Investigación en Cáncer Translacional y Terapia Celular, Centro Médico Siglo XXI, Ciudad de México, México.
authors.forename: Horacio Astudillo-de
authors.initials: HA
authors.lastname: la Vega
authors.affiliation: Universidad Autónoma de la Ciudad de México, Posgrado en Ciencias Genómicas, Ciudad de México, México. genomicas@yahoo.com.mx.|San Lorenzo 290. Col. Del Valle. CP 03100, Mexico City, México. genomicas@yahoo.com.mx.
authors.forename: César
authors.initials: C
authors.lastname: López-Camarillo
mesh_terms: D020413:3' Untranslated Regions; D001943:Breast Neoplasms / Q000235:genetics*; D018797:Cell Cycle Proteins / Q000235:genetics* / Q000378:metabolism; D045744:Cell Line, Tumor; D002465:Cell Movement; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D061986:MCF-7 Cells; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D035683:MicroRNAs / Q000235:genetics*; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D017027:Protein Tyrosine Phosphatases / Q000235:genetics* / Q000378:metabolism; D044767:Ubiquitin-Protein Ligases / Q000235:genetics* / Q000378:metabolism; D000098563:Seven in Absentia Proteins
chemical_list: D020413:3' Untranslated Regions; D018797:Cell Cycle Proteins; C000603398:MIRN944 microRNA, human; D008565:Membrane Proteins; D035683:MicroRNAs; D009687:Nuclear Proteins; D044767:Ubiquitin-Protein Ligases; D000098563:Seven in Absentia Proteins; C490198:PTP4A1 protein, human; D017027:Protein Tyrosine Phosphatases
keywords: Actin cytoskeleton; Breast cancer; Invasion; Migration; PTP4A1; SIAH1; miR-944