title: A genetic variation in microRNA target site of KRT81 gene is associated with survival in early-stage non-small-cell lung cancer.
abstract: BACKGROUND
  MicroRNAs (miRNAs) have a key role in carcinogenesis through negative regulation of their target genes. Therefore, genetic variations in miRNAs or their target sites may affect miRNA-mRNA interactions, thereby result in altered expression of target genes. This study was conducted to investigate the associations between single-nucleotide polymorphisms (SNP) located in the miRNA target sites (poly-miRTSs) and survival of patients with early-stage non-small-cell lung cancer (NSCLC).
  
  
  METHODS
  Using public SNP database and miRNA target sites prediction program, 354 poly-miRTSs were selected for genotyping. Among these, 154 SNPs applicable to Sequenom's MassARRAY platform were investigated in 357 patients. A replication study was carried out on an independent patient population (n = 479). Renilla luciferase assay and reverse transcription-polymerase chain reaction were conducted to examine functional relevance of potentially functional poly-miRTSs.
  
  
  RESULTS
  Of the 154 SNPs analyzed in a discovery set, 14 SNPs were significantly associated with survival outcomes. Among these, KRT81 rs3660G>C was found to be associated with survival outcomes in the validation cohort. In the combined analysis, patients with the rs3660 GC + CC genotype had a significantly better overall survival compared with those with GG genotype [adjusted hazard ratio (aHR) for OS, 0.65; 95% confidence interval (CI) 0.50-0.85; P = 0.001]. An increased expression of the reporter gene for the C allele of rs3660 compared with the G allele was observed by luciferase assay. Consistently, the C allele was associated with higher relative expression level of KRT81 in tumor tissues.
  
  
  CONCLUSIONS
  The rs3660G>C affects KRT81 expression and thus influences survival in early-stage NSCLC. The analysis of the rs3660G>C polymorphism may be useful to identify patients at high risk of a poor disease outcome.
authors.affiliation: Lung Cancer Center, Kyungpook National University Medical Center, Daegu; Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu.
authors.forename: S Y
authors.initials: SY
authors.lastname: Lee
authors.affiliation: Lung Cancer Center, Kyungpook National University Medical Center, Daegu; Department of Biochemistry and Cell Biology, School of Medicine. Electronic address: jechoi.9711@gmail.com.
authors.forename: J E
authors.initials: JE
authors.lastname: Choi
authors.affiliation: The Molecular Diagnostics & Imaging Research Institute.
authors.forename: H S
authors.initials: HS
authors.lastname: Jeon
authors.affiliation: Department of Biochemistry and Cell Biology, School of Medicine.
authors.forename: M J
authors.initials: MJ
authors.lastname: Hong
authors.affiliation: Department of Biochemistry and Cell Biology, School of Medicine.
authors.forename: Y Y
authors.initials: YY
authors.lastname: Choi
authors.affiliation: Department of Biochemistry and Cell Biology, School of Medicine.
authors.forename: H G
authors.initials: HG
authors.lastname: Kang
authors.affiliation: Lung Cancer Center, Kyungpook National University Medical Center, Daegu; Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu.
authors.forename: S S
authors.initials: SS
authors.lastname: Yoo
authors.affiliation: Departments of Thoracic Surgery.
authors.forename: E B
authors.initials: EB
authors.lastname: Lee
authors.affiliation: Pathology.
authors.forename: J Y
authors.initials: JY
authors.lastname: Jeong
authors.affiliation: Biostatistics Center, School of Medicine, Kyungpook National University, Daegu.
authors.forename: W K
authors.initials: WK
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu.
authors.forename: J
authors.initials: J
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu.
authors.forename: S I
authors.initials: SI
authors.lastname: Cha
authors.affiliation: Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu.
authors.forename: C H
authors.initials: CH
authors.lastname: Kim
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Seoul National University School of Medicine, Seoul.
authors.forename: Y T
authors.initials: YT
authors.lastname: Kim
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Seoul National University School of Medicine, Seoul.
authors.forename: S
authors.initials: S
authors.lastname: Jheon
authors.affiliation: Department of Internal Medicine, Konyang University Hospital, Daejeon.
authors.forename: J W
authors.initials: JW
authors.lastname: Son
authors.affiliation: Lung Cancer Center, Kyungpook National University Medical Center, Daegu; Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu; Department of Biochemistry and Cell Biology, School of Medicine; BK21 Plus KNU Biomedical Convergence Program, Department of Biomedical Science, Kyungpook National University, Daegu, Republic of Korea.
authors.forename: J Y
authors.initials: JY
authors.lastname: Park
mesh_terms: D020413:3' Untranslated Regions; D000368:Aged; D001665:Binding Sites; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics* / Q000378:metabolism / Q000401:mortality / Q000473:pathology / Q000628:therapy; D019295:Computational Biology; D030541:Databases, Genetic; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D057809:HEK293 Cells; D006801:Humans; D053208:Kaplan-Meier Estimate; D053564:Keratins, Hair-Specific / Q000235:genetics* / Q000378:metabolism; D053531:Keratins, Type II / Q000235:genetics* / Q000378:metabolism; D008175:Lung Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000401:mortality / Q000473:pathology / Q000628:therapy; D008297:Male; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D008875:Middle Aged; D009367:Neoplasm Staging; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D016016:Proportional Hazards Models; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012307:Risk Factors; D013997:Time Factors; D014162:Transfection
chemical_list: D020413:3' Untranslated Regions; C507600:KRT81 protein, human; D053564:Keratins, Hair-Specific; D053531:Keratins, Type II; D035683:MicroRNAs; D012333:RNA, Messenger
keywords: KRT81; miRNA target sites; non-small cell lung cancer; polymorphisms