Overexpression of the mitotic spindle assembly checkpoint genes hBUB1, hBUBR1 and hMAD2 in thyroid carcinomas with aggressive nature.
BACKGROUND
The mitotic spindle assembly checkpoint (MSAC) genes are responsible for preventing chromosome missegregation. MSAC gene expressions have been reported to be associated with tumor cell proliferation or unfavorable cancer behavior. The present study was conducted to preliminary investigate the MSAC gene expressions in thyroid neoplasms.


METHODS
Expression levels of MSAC genes (hBUB1, hBUBR1, hBUB3 and hMAD2) were evaluated in 9 follicular thyroid adenomas (FAs), 9 follicular thyroid carcinomas (FTCs), 21 papillary thyroid carcinomas (PTCs), 5 anaplastic (undifferentiated) thyroid carcinomas (ATCs) and 3 adjacent normal thyroid tissues (NTs) by real-time quantitative RT-PCR. These gene expressions were compared between undifferentiated thyroid carcinomas (ATCs) and differentiated thyroid carcinomas (DTCs) and between advanced DTCs and non-advanced DTCs. DTCs included PTCs and FTCs. Advanced DTCs were defined as carcinoma with aggressive nature such as extrathyroid extension, distant metastasis, recurrence or death from the disease.


RESULTS
MSAC gene expressions varied in different thyroid tumors and fell in the order of ATC, DTC (PTC and FTC), FA and NT Carcinomas had higher expression compared to adenoma or normal tissue. hBUB1, hBUBR1 and hMAD2 expressions in ATCs were significantly higher than those in DTCs (p<0.005). hBUBR1 and hMAD2 expressions in advanced DTCs were significantly higher than those in non-advanced DTCs (p<0.05).


CONCLUSIONS
The MSAC genes were overexpressed in thyroid carcinomas with aggressive nature. Further studies are required to clarify the relationship between the MSAC gene expressions and thyroid cancer behavior.
Wada
Nobuyuki
N
Department of General Surgery, Yokohama City University, 3-9 Fukuura, Kanazawa-ku, Yokohama City, Kanagawa, Japan. Wadan523@aol.com
Yoshida
Akira
A
Miyagi
Yohei
Y
Yamamoto
Toshiharu
T
Nakayama
Hirotaka
H
Suganuma
Nobuyasu
N
Matsuzu
Kenichi
K
Masudo
Katsuhiko
K
Hirakawa
Shohei
S
Rino
Yasushi
Y
Masuda
Munetaka
M
Imada
Toshio
T
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002135:Calcium-Binding Proteins / Q000096:biosynthesis / Q000235:genetics*; D018797:Cell Cycle Proteins / Q000096:biosynthesis / Q000235:genetics*; D002648:Child; D005260:Female; D015870:Gene Expression; D006801:Humans; D064246:Mad2 Proteins; D008297:Male; D008875:Middle Aged; D017346:Protein Serine-Threonine Kinases / Q000096:biosynthesis / Q000235:genetics*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D012097:Repressor Proteins / Q000096:biosynthesis / Q000235:genetics*; D008941:Spindle Apparatus / Q000235:genetics* / Q000378:metabolism; D013964:Thyroid Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology
D002135:Calcium-Binding Proteins; D018797:Cell Cycle Proteins; C577697:MAD2L1 protein, human; D064246:Mad2 Proteins; D012333:RNA, Messenger; D012097:Repressor Proteins; C584277:BUB1 protein, human; C090464:Bub1 spindle checkpoint protein; D017346:Protein Serine-Threonine Kinases