Expression of bcl-2 and bax in cervical intraepithelial neoplasia and invasive squamous cell carcinoma of the uterine cervix.
Bcl-2 protein together with the pro-apoptotic protein bax, are thought to function by forming homo- and heterotypic dimers which control the progression to apoptosis. In this immunohistochemical study we investigated the expression of bcl-2 and bax apoptosis related proteins in cervical intraepithelial neoplasia and invasive squamous cell carcinoma of the uterine cervix. Twenty-four cervical intraepithelial neoplasias grade 1-2 (CIN I/II), 38 grade 3 (CIN III), and 53 invasive squamous cell carcinomas (ISCC) were investigated by immunohistochemical staining for bcl-2 and bax protein. Bcl-2 immunoreactivity was found in five of the 24 CIN I/II cases (20.8%), 18 of 38 CIN II cases (47.4%) and nine of 53 ISCC cases (17%). The positivity for CIN III was significantly higher than for CIN I/II or ISCC (p=0.0351 and p=0.0018, respectively). The percentage of bax immunopositivity was somewhat higher in CIN III than in CIN I/II but this slight difference was not statistically significant. Correlation of the immunostaining results with tumor grade revealed a significant difference for bcl-2 which was more frequently immunopositive in well-differentiated tumors than in poorly-differentiated tumors. There was no significant relation between bax expression and tumor differentiation. Our results suggest that alterations of bcl-2 and bax expression may occur as a relatively early event in cervical tumorigenesis.
Aletra
C
C
Department of Pathology, University of Patras Medical School, Greece.
Ravazoula
P
P
Scopa
C
C
Kounelis
S
S
Sotiropoulou
G
G
Kourounis
G
G
Ladopoulos
I
I
Bonikos
D
D
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000473:pathology; D002584:Cervix Uteri / Q000378:metabolism; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis*; D002583:Uterine Cervical Neoplasms / Q000378:metabolism* / Q000473:pathology; D051028:bcl-2-Associated X Protein; D002578:Uterine Cervical Dysplasia / Q000378:metabolism* / Q000473:pathology
C494826:BAX protein, human; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein