Apoptosis in nasopharyngeal carcinoma as related to histopathological characteristics and clinical stage.
OBJECTIVE
We investigated the significance of apoptosis, using the terminal deoxynucleotidyl transferase mediated dUTP-digoxigenin nick end-labelling method, in nasopharyngeal carcinoma biopsy samples.


RESULTS
The apoptotic index (AI) in 50 nasopharyngeal carcinomas was compared with various histopathological features and clinical stage. Also, the AI was correlated with p53, bcl-2 and Ki67 expression by immunohistochemistry. In histopathological studies, the AI was significantly higher in mixed cellular type (MC) than in keratizing squamous cell type (KS) and spindle cell type (SC) (P < 0.001) which worsens prognosis. In tumour stage analyses, AI was higher in early stage (stage 2 and 3) than in high stage (stage 4). In addition, there was a significant correlation between the AI and p53 expression (P < 0.001) but not with proliferative activity (P = 0.15). In NPC containing p53 protein positive tumour cells, there was a significantly higher apoptotic rate.


CONCLUSIONS
These findings indicate that apoptosis is related to type and stage of nasopharyngeal carcinoma. They also confirm the role of p53 in regulating tumour apoptosis.
Department of Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
H J
HJ
Harn
H F
HF
Hsieh
L I
LI
Ho
C P
CP
Yu
J H
JH
Chen
C C
CC
Chiu
H C
HC
Fan
W H
WH
Lee
D000328:Adult; D000368:Aged; D017209:Apoptosis; D001706:Biopsy; D002277:Carcinoma / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000378:metabolism / Q000473:pathology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism
D019394:Ki-67 Antigen; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53