Immunofluorescence expression of Ki-67, p53 and cyclin inhibitors (p16ink4a, p21 and p27) in low-grade cervical lesions versus high-grade cervical lesions. Research study on cell cultures.

OBJECTIVE:The aim of this research was to assess the immunofluorescence expression (IFE) of cell cycle regulators p16ink4a, p21, p27, in association with proliferation and prognosis factors Ki-67, p53 respectively, in cell cultures, obtained from different types of cervical intra-epithelial lesions. The final purpose was to distinguish a best marker able to identify with high accuracy the high-grade squamous intra-epithelial lesion. MATERIALS AND METHODS:The study was carried out on 68 epithelial cell cultures. Three senior specialists have analyzed 500 cells/case individually. The statistic analysis for correlation between used markers has been performed. RESULTS:The study batch revealed a very low expression of investigated parameters (<1%) in negative cases for malignancy and intraepithelial lesion (NMIL), a progressive exponential expression in low-grade squamous intraepithelial lesion (LSIL), and a very high expression in high-grade squamous intra-epithelial lesion (HSIL) and invasive squamous cervical carcinoma (ISCC). Ki-67 and p53 were overexpressed in nuclei both in LSIL and HSIL. A slightly direct correlation between p21 and Ki-67 (r=0.35, p<0.001) was observed in HSIL. Statistically significant correlations were noticed between some markers: p16ink4a and p27 (r=0.4, p=0.03), p16ink4a and Ki-67 (r=-0.4, p=0.002). CONCLUSIONS:The most reliable parameters for assessing HSIL and ISCC proved to be Ki-67 and p16ink4a. Both were with percentages and intensity of IFE around 100% and higher immunoexpression within the nucleus of cell cultures. Our study reveals that p27 cyclin inhibitor was not reliable in differentiating between LSIL and HSIL.