title: Polo-like kinase 1 expression in medullary carcinoma of the thyroid: its relationship with clinicopathological features.
abstract: OBJECTIVE
  Polo-like kinase 1 (PLK1) is one of the serine-threonine kinases that contributes to cell mitosis and is regarded as a marker of cellular proliferation. However, its protein expression in human carcinoma has not been studied in depth. In this study, we investigated PLK1 expression in medullary thyroid carcinoma by means of immunohistochemistry.
  
  
  METHODS
  We immunohistochemically investigated PLK1 expression in 67 cases of medullary thyroid carcinoma.
  
  
  RESULTS
  The PLK1 expression level was elevated in 43 of the 67 cases (64.1%). Furthermore, the expression level was directly linked to lymph node metastasis, advanced stage and male sex. All patients who were negative for PLK1 expression are currently alive without tumor recurrence, while 6 of the 43 PLK1-positive patients showed recurrence and 3 have already died of this disease.
  
  
  CONCLUSIONS
  These findings suggest that PLK1 expression significantly reflects aggressive characteristics of medullary thyroid carcinoma.
authors.affiliation: Kuma Hospital, Kobe, and Department of Pathology, Wakayama Medical University, Japan. ito01@kuma-h.or.jp
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Ito
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yoshida
authors.forename: Chisato
authors.initials: C
authors.lastname: Tomoda
authors.forename: Takashi
authors.initials: T
authors.lastname: Uruno
authors.forename: Yuuki
authors.initials: Y
authors.lastname: Takamura
authors.forename: Akihiro
authors.initials: A
authors.lastname: Miya
authors.forename: Kaoru
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Fumio
authors.initials: F
authors.lastname: Matsuzuka
authors.forename: Kanji
authors.initials: K
authors.lastname: Kuma
authors.forename: Kennichi
authors.initials: K
authors.lastname: Kakudo
authors.forename: Akira
authors.initials: A
authors.lastname: Miyauchi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018276:Carcinoma, Medullary / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D007564:Japan; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D012008:Recurrence; D012189:Retrospective Studies; D012737:Sex Factors; D013964:Thyroid Neoplasms / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D000097869:Polo-Like Kinase 1
chemical_list: D018797:Cell Cycle Proteins; D011494:Protein Kinases; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D000097869:Polo-Like Kinase 1