title: Microarray analysis of papillary thyroid cancers in Korean.
abstract: OBJECTIVE
  Papillary thyroid cancer (PTC) is the most common malignancy of the thyroid gland. It involves several molecular mechanisms. The BRAF V600E mutation has been identified as the most common genetic abnormality in PTC. Moreover, it is known to be more prevalent in Korean PTC patients than in patients from other countries. We investigated distinct genetic profiles in Korean PTC through cDNA microarray analysis.
  
  
  METHODS
  Transcriptional profiles of five PTC samples and five paired normal thyroid tissue samples were generated using cDNA microarrays. The tumors were genotyped for BRAF mutations. The results of the cDNA microarray gene expression analysis were confirmed by real-time PCR and immunohistochemistry analysis of 35 PTC patients.
  
  
  RESULTS
  Four of the five patients whose PTC tissues were subjected to microarray analysis were found to carry the BRAF V600E mutation. Microarrays analysis of the five PTC tissue samples showed the expression of 96 genes to be increased and that of 16 genes decreased. Real-time reverse transcription-polymerase chain reaction (RT-PCR) confirmed increased expression of SLC34A2, TM7SF4, COMP, KLK7, and KCNJ2 and decreased expression of FOXA2, SLC4A4, LYVE-1, and TFCP2L1 in PTC compared with normal tissue. Of these genes, TFCP2L1, LYVE-1, and KLK7 were previously unidentified in PTC microarray analysis. Notably, Foxa2 activity in PTC was reduced, as shown by its cytoplasmic localization, in immunohistochemical analyses.
  
  
  CONCLUSIONS
  These findings demonstrate both similarities and differences between our results and previous reports. In Korean cases of PTC, Foxa2 activity was reduced with its cytoplasmic accumulation. Further studies are needed to confirm the relationship between FOXA2 and BRAF mutations in Korean cases of PTC.
authors.affiliation: Department of Internal Medicine, Catholic University of Daegu School of Medicine, Daegu, Korea.
authors.forename: Hyun Sook
authors.initials: HS
authors.lastname: Kim
authors.forename: Do Hyung
authors.initials: DH
authors.lastname: Kim
authors.forename: Ji Yeon
authors.initials: JY
authors.lastname: Kim
authors.forename: Nam Ho
authors.initials: NH
authors.lastname: Jeoung
authors.forename: In Kyu
authors.initials: IK
authors.lastname: Lee
authors.forename: Jin Gu
authors.initials: JG
authors.lastname: Bong
authors.forename: Eui Dal
authors.initials: ED
authors.lastname: Jung
mesh_terms: D000328:Adult; D000368:Aged; D002291:Carcinoma, Papillary / Q000235:genetics*; D005260:Female; D020869:Gene Expression Profiling; D051542:Hepatocyte Nuclear Factor 3-beta / Q000032:analysis / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D007610:Kallikreins / Q000032:analysis / Q000235:genetics; D007723:Korea; D008297:Male; D008875:Middle Aged; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods*; D016133:Polymerase Chain Reaction; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics*; D013964:Thyroid Neoplasms / Q000235:genetics*; D033921:Vesicular Transport Proteins / Q000032:analysis / Q000235:genetics
chemical_list: C496502:FOXA2 protein, human; C119248:LYVE1 protein, human; D033921:Vesicular Transport Proteins; D051542:Hepatocyte Nuclear Factor 3-beta; C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf; C082472:KLK7 protein, human; D007610:Kallikreins