title: [Expression and clinical significance of the thyroid transcription factor 1 in Xuanwei lung adenocarcinoma].
abstract: OBJECTIVE
  The present study aims to detect the expressions of the thyroid transcription factor 1 (TTF-1) mRNA and protein in Xuanwei lung adenocarcinoma line (XWLC-05). We also investigated the relationship of TTF-1 with Ki-67 protein and analyzed the prognostic value of the TTF-1 protein in Xuanwei lung adenocarcinoma patients.
  
  
  METHODS
  The expression of TTF-1 mRNA was evaluated by quantitative real-time RT-PCR (qRT-PCR), while proteins of TTF-1 and Ki-67 were detected by immunohistochemistry in XWLC-05. The expressions of TTF-1 and Ki-67 was detected in 96 resected cases of Xuanwei lung adenocarcinoma by immunohistochemistry from January 2008 to March 2012.
  
  
  RESULTS
  TTF-1 mRNA was low and protein was absent in XWLC-05. The expression of Ki67 protein was 100% (high proliferative activity) in XWLC-05. All samples were Xuanwei lung adenocarcinoma (n=96) and TNM stages were I-II 66% (63/96) and III 34% (33/96). Immunohistochemical analysis showed the expression of TTF-1 in 89 (93%) of 96 and Ki-67 in 69 (70%) of 96. The positive rate of TTF-1 protein was 38 (96%) of 39 in well-differentiated phenotype and 51 (89%) 57 in moderately/poorly-differentiated phenotype. Patients with strong immunohistochemical expression of TTF-1 were statistically associated with well-differentiated phenotype (P=0.002), has inverse correlation with Ki-67 expression (P=0.01), and no correlation with age, sex, smoking history, and stages. The result from the Kaplan-Meier survival analysis showed that stages TTF-1 and Ki-67 were significantly associated with the prognosis of Xuanwei lung adenocarcinoma patients. The median progression-free survival in patients with I-II stages, strong positive expression TTF-1 and negative, and weak expressions Ki-67 groups was remarkably higher than those patients with III stage (46 months vs 32 months, P=0.001), negative and weak expressions TTF-1 (45 months vs 35 months, P=0.036) and strong positive expression Ki-67 groups (46 months vs 40 months, P=0.048), respectively.
  
  
  CONCLUSIONS
  Our results presented here suggest that TTF-1 may serve as a tumor suppressor gene based on its inverse correlation with Ki-67 proliferative activity. Patients with strong TTF-1 protein expression group tend to have a significantly better prognosis than patients with negative and weak TTF-1 protein expression group in Xuanwei lung adenocarcinoma.
authors.affiliation: Department of Oncology, the Second People Hospital of Yunnan Province, Kunming 650021, China.
authors.forename: Yunfen
authors.initials: Y
authors.lastname: Zu
authors.forename: Xicai
authors.initials: X
authors.lastname: Wang
authors.forename: Xin
authors.initials: X
authors.lastname: Liu
authors.forename: Yan
authors.initials: Y
authors.lastname: Chen
authors.forename: Chengwen
authors.initials: C
authors.lastname: Li
authors.forename: Xueqin
authors.initials: X
authors.lastname: Shang
authors.forename: Yucheng
authors.initials: Y
authors.lastname: Xie
authors.forename: Hongyuan
authors.initials: H
authors.lastname: Zhao
authors.forename: Jiying
authors.initials: J
authors.lastname: Wang
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D000077192:Adenocarcinoma of Lung; D045744:Cell Line, Tumor; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D053208:Kaplan-Meier Estimate; D019394:Ki-67 Antigen / Q000378:metabolism; D008175:Lung Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism*; D011379:Prognosis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D000074482:Thyroid Nuclear Factor 1; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism*
chemical_list: D019394:Ki-67 Antigen; C000614412:NKX2-1 protein, human; D009687:Nuclear Proteins; D012333:RNA, Messenger; D000074482:Thyroid Nuclear Factor 1; D014157:Transcription Factors