Bmi-1 expression predicts prognosis in squamous cell carcinoma of the tongue.
BACKGROUND
The prognosis of squamous cell carcinoma of the oral tongue is poor and it would be beneficial to find prognostic markers to better adjust treatment. Bmi-1 controls cell cycle and self-renewal of tissue stem cells, transcription factor c-myc affects cell proliferation and apoptosis, and Snail regulates epithelial-mesenchymal transition. The expression of these markers has been connected to prognosis in many cancer types.


METHODS
Bmi-1, c-myc, and Snail expressions were studied in our material consisting of 73 primarily T1N0M0 oral tongue carcinoma patients. We compared the immunoexpressions of Bmi-1, c-myc, and Snail with clinical parameters including the degree of histological differentiation, tumour size, TNM classification, depth of invasion, and resection margins. In addition, survival analyses were performed, comparing disease-free survival time with the registered protein expression of the markers mentioned above.


RESULTS
A significant correlation between Bmi-1 protein expression and recurrence (log-rank test, P=0.005) was detected. Snail and c-myc expression did not correlate with prognosis. Snail expression correlated with histopathological grade (Fisher's exact test, P=0.007) and with the invasion depth of tumours (chi(2)-test, P=0.037).


CONCLUSIONS
Negative Bmi-1 immunoexpression might serve as a marker of poor prognosis in oral tongue carcinoma patients.
Department of Otolaryngology and Head and Neck Surgery, Helsinki University Central Hospital, Haartmaninkatu 4E, Helsinki, Finland.
V
V
Häyry
L K
LK
Mäkinen
T
T
Atula
H
H
Sariola
A
A
Mäkitie
I
I
Leivo
H
H
Keski-Säntti
J
J
Lundin
C
C
Haglund
J
J
Hagström
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism; D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000556:secondary; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000378:metabolism* / Q000473:pathology; D009687:Nuclear Proteins / Q000378:metabolism*; D063150:Polycomb Repressive Complex 1; D011379:Prognosis; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D016271:Proto-Oncogene Proteins c-myc / Q000378:metabolism; D012097:Repressor Proteins / Q000378:metabolism*; D000071250:Snail Family Transcription Factors; D015996:Survival Rate; D046888:Tissue Array Analysis; D014062:Tongue Neoplasms / Q000378:metabolism* / Q000473:pathology; D014157:Transcription Factors / Q000378:metabolism; D055815:Young Adult
C069077:BMI1 protein, human; D014408:Biomarkers, Tumor; C489427:MYC protein, human; D009687:Nuclear Proteins; D011518:Proto-Oncogene Proteins; D016271:Proto-Oncogene Proteins c-myc; D012097:Repressor Proteins; D000071250:Snail Family Transcription Factors; D014157:Transcription Factors; D063150:Polycomb Repressive Complex 1