Studies on the Expression of the p16 (INK4A), p53, and Ki-67 Labeling Index in Inflammatory and Neoplastic Diseases of the Uterine Cervix

ABSTRACT

BACKGROUND: Prior studies of p16, p53, and Ki-67 expression have suggested that these markers may be preferentially expressed in cervical neoplasms. The purpose of this study was to assess the expression and clinical significance of p16, p53 proteins, and the Ki-67 labeling index in the cervical lesions. METHODS: We analyzed 54 uterine cervical specimens obtained by surgical biopsy. The expression of p16, p53 proteins, and Ki-67 was evaluated by immunohistochemical methods. The immunohistochemical findings were then correlated with the histologic diagnosis. RESULTS: Positive scores for p16, p53, and Ki-67 were seen in 75% (6/8), 0% (0/8), and 13% (1/8) of low grade intraepithelial lesions (LSIL), respectively, and 100% (23/23), 17% (4/23), and 74% (17/23) of high grade intraepithelial lesions (HSIL), respectively, and 100% (10/10), 20% (2/10), and 70% (7/10) of invasive squamous cell carcinomas, respectively. Both normal epithelium and inflammatory lesions scored negative for these three markers in all of the 13 cases. p16 and Ki-67 expression correlated with the severity of uterine cervix lesions. CONCLUSIONS: p16 and Ki-67 are complementary surrogate biomarkers for cervical squamous intraepithelial neoplasia. However, immunohistochemical expression for p53 has no correlation with the grade of cervical squamous intraepithelial neoplasia.