title: Genetic variants in miR-146a, miR-149, miR-196a2, miR-499 and their influence on relative expression in lung cancers.
abstract: BACKGROUND
  The presence of sequence variants in miRNA genes may influence their processing, expression and binding to target mRNAs. Since single miRNA can have a large number of potential mRNA targets, even minor variations in its expression can have influences on hundreds of putative mRNAs.
  
  
  METHODS
  Here, we evaluated 101 paired samples (cancer and normal tissues) from non-small cell lung carcinoma (NSCLC) patients to study the genotype distribution of single nucleotide polymorphisms (SNPs) in miR-146a (rs2910164 C-G), miR-149 (rs2292832 C-T), miR-196a2 (rs11614913 C-T) and miR-499 (rs3746444 G-A) and their influence on the expression of respective miRNAs.
  
  
  RESULTS
  Relative expression of miR-146a, miR-149 and miR-499 were comparable in NSCLC and in paired control tissues. On the contrary, we clearly detected a significant increase (p<0.001) of miR-196a2 expression in NSCLC. In particular we found a significant association between miR-196a2 CC genotype and high expression, whereas TT geno-type showed a very low expression in comparison to both CT (p<0.005) and CC patients (p<0.01). We did not find any association between miR-149, miR-196a2 and miR-499 genotype and risk of NSCLC. Conversely, CG genotype of miR-146a appeared associated to an increased risk for NSCLC (p=0.042 and 1.77 OR).
  
  
  CONCLUSIONS
  Our results seem to demonstrate that sequence variants of miR-196a2 can have an influence on its expression, while miR-146a can have a role in increasing the risk of NSCLC.
authors: Clinical Biochemistry, Department of Clinical Physiopathology, University of Florence, Florence, Italy.
authors: Serena
authors: S
authors: Vinci
authors: Stefania
authors: S
authors: Gelmini
authors: Nicola
authors: N
authors: Pratesi
authors: Simona
authors: S
authors: Conti
authors: Francesca
authors: F
authors: Malentacchi
authors: Lisa
authors: L
authors: Simi
authors: Mario
authors: M
authors: Pazzagli
authors: Claudio
authors: C
authors: Orlando
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics* / Q000378:metabolism; D016022:Case-Control Studies; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000378:metabolism; D008297:Male; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D060888:Real-Time Polymerase Chain Reaction
chemical_list: C542542:MIRN146 microRNA, human; C551557:MIRN149 microRNA, human; C542543:MIRN196 microRNA, human; C548683:MIRN499 microRNA, human; D035683:MicroRNAs