[Expressions of MAD2 and p55CDC in prostate cancer and their correlations with the prostate cancer grading].
OBJECTIVE
To investigate if downregulation of two mitotic checkpoint proteins, MAD2 and p55CDC, is a frequent event in human prostate cancer and whether decreased expression of these two proteins are associated with progression of prostate cancer.


METHODS
Using immunohistochemistry technique, the expressions of MAD2 and p55CDC proteins are examined in 46 benign prostate hyperplasia (BPH) and 65 prostate cancer tissues. Differential expressions were compared first between BPH and prostate cancer specimens, and then among prostate cancer samples with different Gleason grades.


RESULTS
We found that down-regulation of MAD2 and p55CDC expressions was significant in prostate cancer (96% and 83%, respectively) compared to BPH (19.5% and 4.3%, respectively) (P<0.001). In addition, decreased expression levels of these two proteins were associated with increased Gleason grade.


CONCLUSIONS
Our results indicate that loss of MAD2 and p55CDC protein expression is a frequent event in prostate carcinoma and the decreased expressions of these two proteins are associated with increased Gleason grade. Our results provide first in vivo evidence to support the hypothesis that down regulation of certain mitotic checkpoint proteins plays an important part in human tumourigenesis.
Xu
Kexin
K
Department of Urology, Peking University People's Hospital, Beijing 100044, China. cavinx@hotmail.com
Wang
Xianghong
X
Xue
Weicheng
W
Wang
Xiaofeng
X
Hou
Shukun
S
D002135:Calcium-Binding Proteins / Q000032:analysis*; D064199:Cdc20 Proteins; D018797:Cell Cycle Proteins / Q000032:analysis*; D006801:Humans; D007150:Immunohistochemistry; D064246:Mad2 Proteins; D008297:Male; D009367:Neoplasm Staging; D011471:Prostatic Neoplasms / Q000737:chemistry* / Q000473:pathology; D012097:Repressor Proteins
D002135:Calcium-Binding Proteins; D064199:Cdc20 Proteins; D018797:Cell Cycle Proteins; C577697:MAD2L1 protein, human; D064246:Mad2 Proteins; D012097:Repressor Proteins; C577488:CDC20 protein, human