bcl-2 immunoreactivity, human papillomavirus DNA, and cervical intraepithelial neoplasia

The aim of this study was to identify the role of bcl-2 protein expression in precancerous lesions of the cervix in patients from Johannesburg, South Africa and to correlate this expression with human papillomavirus (HPV) status. Archival cervical biopsy specimens (n = 107) of normal squamous epithelia (n = 18), pure HPV squamous epithelial lesions (n = 15), cervical intraepithelial neoplasia (CIN) I lesions (n = 17), CIN II lesions (n = 26), and CIN III lesions (n = 31) underwent bcl-2 immunohistochemical analysis with use of the streptavidin-biotin complex/horseradish peroxidase system and nonisotopic in situ hybridization for the detection of HPV DNA. Although 45 (61%) of the 74 CIN lesions demonstrated bcl-2 protein expression in the epithelia, most seemed to be in a patchy basal cell distribution, with a 1+ to 2+ intensity. Furthermore, comparison of bcl-2 immunoreaction between the low and high grades of the CIN lesions did not reveal significant differences. In addition, there was no apparent link between the presence of HPV DNA and bcl-2 expression in the CIN lesions. In contrast to previous studies that showed an increase in bcl-2 immunostaining intensity with increasing severity of CIN, only 4 (5.4%) of our 74 CIN specimens satisfied this pattern. Hence, we suggest that bcl-2 protein expression might not play a significant role in the majority of CIN lesions in this population group and that it might not correlate with HPV status.