Cyclooxygenase-2 regulates the degree of apoptosis by modulating bcl-2 protein in pleomorphic adenoma and mucoepidermoid carcinoma of the parotid gland.
CONCLUSIONS
These results suggest that COX-2 and bcl-2 protein were overexpressed and that apoptosis was reduced in MEC compared to PMA, and that COX-2 may regulate the degree of apoptosis by modulating bcl-2 protein in PMA and MEC.


OBJECTIVE
Cyclooxygenase (COX)-2 plays a crucial role in tumorigenesis and overexpression of COX-2 in vitro accompanied by overexpression of bcl-2 protein has been shown to reduce apoptosis. The purpose of this study was to verify that COX-2 regulates the degree of apoptosis by modulating bcl-2 protein in benign and malignant parotid gland tumors. : We examined archival formalin-fixed, paraffin-embedded tissue sections of 10 pleomorphic adenomas (PMAs) and 10 mucoepidermoid carcinomas (MECs) by immunostaining with anti-COX-2, anti-bcl-2 and anti-single-stranded DNA (ssDNA) antibodies. Labeling indices of the three antibodies were calculated using computer-assisted image analysis.


RESULTS
Labeling indices (mean+/-SD) of anti-COX-2 antibody in PMA and MEC were 2.05+/-1.30 and 11.2+/-2.95, respectively (p < 0.001), those of anti-bcl-2 antibody were 2.00+/-1.28 and 9.68+/-4.05, respectively (p < 0.001) and those of anti-ssDNA antibody were 8.06+/-2.54 and 2.08+/-1.47; respectively (p <0.001). Correlation coefficients between the labeling indices of anti-COX-2 antibody and anti-bcl-2 antibody, anti-bcl-2 antibody and anti-ssDNA antibody and anti-COX-2 antibody and anti-ssDNA antibody were 0.88, -0.75 and -0.76, respectively (p <0.001).
Sakamoto
Takashi
T
Department of Otorhinolaryngology, Mutual Aid Association for Tokyo Metropolitan Teachers and Officials, Sanraku Hospital, Tokyo, Japan. ta-saka@nifty.com
Uozaki
Hiroshi
H
Kondo
Kenji
K
Imauchi
Yutaka
Y
Yamasoba
Tatsuya
T
Sugasawa
Masashi
M
Kaga
Kimitaka
K
D008949:Adenoma, Pleomorphic / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D000328:Adult; D000368:Aged; D000906:Antibodies / Q000276:immunology; D017209:Apoptosis / Q000502:physiology*; D018277:Carcinoma, Mucoepidermoid / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D051546:Cyclooxygenase 2; D004277:DNA, Single-Stranded / Q000276:immunology; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D008297:Male; D008565:Membrane Proteins; D008875:Middle Aged; D010307:Parotid Neoplasms / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D011451:Prostaglandin-Endoperoxide Synthases / Q000276:immunology / Q000502:physiology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000276:immunology / Q000378:metabolism*; D015854:Up-Regulation
D000906:Antibodies; D004277:DNA, Single-Stranded; D008565:Membrane Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases