Bmi-1 expression predicts prognosis for patients with gastric carcinoma.
OBJECTIVE
The Bmi-1 gene is a transcriptional repressor involved in oncogenesis in various human cancers. Here, we examine Bmi-1 expression in gastric carcinoma (GC) and investigates whether its expression correlates with patient prognosis.


METHODS
Immunohistochemistry was performed using an anti-Bmi-1 antibody on primary tumor samples of 146 cases of GC. The association between Bmi-1 expression and the clinicopathological status and prognosis of GC patients was statistically analyzed. Furthermore, reverse transcription-PCR (RT-PCR) and Western blotting were performed to determine the expression levels of Bmi-1 in an additional 8 GC and the adjacent non-cancerous samples.


RESULTS
Using immunohistochemistry, we found that 99 of 146 paraffin-embedded GC samples expressed Bmi-1 extensively. Statistical analysis showed that Bmi-1 overexpression was highly correlated with tumor size, clinical stage, lymph node metastasis and T classification (P < 0.05), Patients with Bmi-1 expression had shorter overall survival time than those without Bmi-1 expression (P < 0.01). Multivariate analysis indicated that Bmi-1 expression is an independent prognostic factor of GC. RT-PCR and Western blotting showed that Bmi-1 was up-regulated at both the transcriptional and translational levels in the GC tissues compared with the adjacent non-cancerous tissues.


CONCLUSIONS
Bmi-1 may serve as a valuable marker for diagnosis and prognosis of GC.
Department of Gastroenterology, The Second Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
Jian-Hua
JH
Liu
Li-Bing
LB
Song
Xing
X
Zhang
Bao-Hong
BH
Guo
Yan
Y
Feng
Xue-Xian
XX
Li
Wen-Ting
WT
Liao
Mu-Sheng
MS
Zeng
Kai-Hong
KH
Huang
D000368:Aged; D002277:Carcinoma / Q000378:metabolism* / Q000401:mortality* / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D063150:Polycomb Repressive Complex 1; D011237:Predictive Value of Tests; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D012189:Retrospective Studies; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013274:Stomach Neoplasms / Q000378:metabolism* / Q000401:mortality* / Q000473:pathology; D015996:Survival Rate
C069077:BMI1 protein, human; D009687:Nuclear Proteins; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D012097:Repressor Proteins; D063150:Polycomb Repressive Complex 1