title: miR-152 down-regulation is associated with MET up-regulation in leiomyosarcoma and undifferentiated pleomorphic sarcoma.
abstract: OBJECTIVE
  Highly aggressive adult soft tissue sarcomas (STS), i.e., leiomyosarcomas (LMS) and undifferentiated pleomorphic sarcomas (UPS), present complex genomic anomalies and overall 5-year survival rates of 20 to 40%. Here, we aimed to identify new biomarkers that may be employed to improve the treatment of non-translocation STS patients. We validated 12 miRNAs implicated in tumor development using primary STS samples and selected miR-152 for further analysis in STS-derived cell lines.
  
  
  METHODS
  59 primary STS samples (27 LMS and 32 UPS) and 10 matched normal control tissues were included in the study, as well as 3 STS-derived cell lines (HT1080, SW872 and SKLMS1) and a normal control mesenchymal cell line (hMSC). miRNA expression analyses were performed using a TaqMan microRNA Array platform and qRT-PCR (miR-152), respectively. The expression levels of the putative miR-152 targets MET and KIT were assessed using qRT-PCR and immunohistochemistry on tissue microarrays, respectively. In addition, various functional analyses were performed before and after miR-152 transfection into SKLMS1 cells.
  
  
  RESULTS
  We found that 12 pre-selected miRNAs were down-regulated in primary STS tumor samples compared to its normal control samples. A statistically significant miR-152 down-regulation was found to be accompanied by high MET and KIT mRNA levels in both the primary samples and the STS-derived cell lines tested. miR-152 transfection in SKLMS1 cells led to a reduction in KIT and MET mRNA and protein levels which, in turn, was associated with a transient down-regulation of the PI3K/AKT pathway, a transient decrease in cell growth, and a transient increase in both apoptotic and S-phase cells.
  
  
  CONCLUSIONS
  Our data indicate that over-expression of MET and KIT in primary STS samples and its derived cell lines is associated with miR-152 down-regulation. This shift may play a role in STS development and, thus, may be used to identify patients at risk. The effect of MET down-regulation on downstream signaling pathways, such as the PI3K/AKT pathway, may provide a basis for the future design of novel STS treatment strategies.
authors.affiliation: Laboratory of Experimental Oncology, Rizzoli Orthopaedic Institute, Via di Barbiano 1, 10 40136, Bologna, Italy. laura.pazzaglia@ior.it.
authors.forename: Laura
authors.initials: L
authors.lastname: Pazzaglia
authors.affiliation: Laboratory of Experimental Oncology, Rizzoli Orthopaedic Institute, Via di Barbiano 1, 10 40136, Bologna, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Novello
authors.affiliation: Laboratory of Experimental Oncology, Rizzoli Orthopaedic Institute, Via di Barbiano 1, 10 40136, Bologna, Italy.
authors.forename: Amalia
authors.initials: A
authors.lastname: Conti
authors.affiliation: Laboratory of Experimental Oncology, Rizzoli Orthopaedic Institute, Via di Barbiano 1, 10 40136, Bologna, Italy.
authors.forename: Serena
authors.initials: S
authors.lastname: Pollino
authors.affiliation: Laboratory of Experimental Oncology, Rizzoli Orthopaedic Institute, Via di Barbiano 1, 10 40136, Bologna, Italy.
authors.forename: Piero
authors.initials: P
authors.lastname: Picci
authors.affiliation: Laboratory of Experimental Oncology, Rizzoli Orthopaedic Institute, Via di Barbiano 1, 10 40136, Bologna, Italy.
authors.forename: Maria Serena
authors.initials: MS
authors.lastname: Benassi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis*; D015153:Blotting, Western; D015536:Down-Regulation; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics*; D055785:Gene Knockdown Techniques; D006801:Humans; D007150:Immunohistochemistry; D007890:Leiomyosarcoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D008297:Male; D035683:MicroRNAs / Q000096:biosynthesis* / Q000235:genetics; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D019009:Proto-Oncogene Proteins c-kit / Q000096:biosynthesis*; D019859:Proto-Oncogene Proteins c-met / Q000096:biosynthesis*; D012509:Sarcoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D012983:Soft Tissue Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D046888:Tissue Array Analysis; D015854:Up-Regulation
chemical_list: D014408:Biomarkers, Tumor; C550856:MIRN152 microRNA, human; D035683:MicroRNAs; C491743:MET protein, human; D019009:Proto-Oncogene Proteins c-kit; D019859:Proto-Oncogene Proteins c-met
keywords: Met; New targets; Soft tissue sarcoma; miR-152