Relationship between p16(INK4a), pRb and high risk HPV infection and recurrence

Nam, Eun Ji; Kim, Hye Yeon; Kim, Sang Woon; Yoon, Bo Sung; Kim, Jae Hoon; Kim, Young Tae; Kim, Jae Wook; Cho, Nam Hoon; Kim, Sunghoon

Abstract

OBJECTIVE
The purpose of this study was to identify the abnormal expressions of p16(INK4a) and pRb in cervical intraepithelial neoplasia (CIN), and then to determine the relationship between the levels of p16(INK4a) and pRb and high risk HPV infection and recurrence.
METHODS
The study group was composed of 265 formalin-fixed, paraffin-embedded tissue array sections of the uterine cervix collected from women who had underwent biopsy, conization or hysterectomy at our hospital from January 2001 to December 2003. Immunohistochemical stainings for p16(INK4a) and pRb were performed and the association of pRb and p16(INK4a) expressions with clinical features was analyzed retrospectively.
RESULTS
There was positive correlation between p16(INK4a) expression rate and grade of cervical lesion. Meanwhile, there was reverse correlation between pRb expression rate and grade of cervical lesion. The expression rate of p16(INK4a) was higher (33%) in CIN I with high risk HPV infection, than in CIN I without high risk HPV infection (19%). In all CIN lesions, the mean expression rate of p16(INK4a) was lower in recurred group than in those which did not recur. In CIN II and CIN III, the mean expression rate of pRb was higher in recurred group than in those which did not recur.
CONCLUSION
With increasing CIN grade, abnormal expression of p16(INK4a) was increased, but pRb expression was decreased. Relatively decreased p16(INK4a) expressions and increased pRb expressions significantly cooperate to predict a recurrence of the CIN lesions.