Ezrin and E-cadherin expression profile in cervical cytology: a prognostic marker for tumor progression in cervical cancer

Abstract

Background: Cervical cancer (CC) is the fourth cause of mortality by neoplasia in women worldwide. The use of immunomarkers is an alternative tool to complement currently used algorithms for detection of cancer, and to improve selection of therapeutic schemes. Aberrant expression of Ezrin and E-cadherin play an important role in tumor invasion. In this study we analyzed Ezrin and E-cadherin expression in liquid-based cervical cytology samples, and evaluated their potential use as prognostic immunomarkers.

Methods: Immunocytochemical staining of Ezrin and E-cadherin was performed in cervical samples of 125 patients. The cytological or histological diagnostic was performed by Papanicolaou staining or H&E staining, respectively. HPV genotyping was determined using INNO-LIPA Genotyping Extra kit and the HPV physical status by in situ hybridization. Ezrin expression in HaCaT, HeLa and SiHa cell lines was determined by immunocytochemistry, immunofluorescence and Western blot.

Results: High Ezrin expression was observed in cervical cancer samples (70%), samples with multiple infection by HR-HPV (43%), and samples with integrated viral genome (47%). High Ezrin expression was associated with degree of SIL, viral genotype and physical status. In contrast, low E-cadherin expression was found in cervical cancer samples (95%), samples with multiple infection by HR-HPV/LR-HPV (87%) and integrated viral genome (72%). Low E-cadherin expression was associated with degree of SIL and viral genotype. Interestingly, Ezrin nuclear staining was associated with degree of SIL and viral genotype. High Ezrin expression, high percent of nuclear Ezrin and low E-cadherin expression behaved as risk factors for progression to HSIL and cervical cancer.

Conclusions: Ezrin and E-cadherin expression profile in cervical cytology samples could be a potential prognostic marker, useful for identifying cervical lesions with a high-risk of progression to cervical cancer.

Keywords: Cervical cancer; Cervical cytology; E-cadherin; Ezrin; HPV; Immunomarker; SIL.

Fig. 1

Ezrin and E-cadherin expression in cervical cytology samples. Immunocytochemical staining using streptavidin-biotin peroxidase technique. a and b (Negative control): Non-SIL samples without primary antibody, 60X. c to l, 40X. Red arrow: Negative/low expression; Blue arrow: moderate expression; Black arrow: high expression of Ezrin or E-cadherin

Fig. 2

Subcellular localization of Ezrin in squamous intraepithelial lesions and cervical cancer. Immunocytochemistry for Ezrin protein, 60×. a Non-SIL, b LSIL, c HSIL, d cervical cancer. Black arrow: cell with positive nuclei for Ezrin. Blue arrow: cell negative to Ezrin nuclear

Fig. 3

Ezrin expression in cervical cell lines in vitro. a Western blot for Ezrin expression (left) and densitometry corresponding to three independent replicates (right), *t-student test, p value< 0.05. b Top panel: Immunocytochemistry (100×), black arrow indicates perinuclear staining; bottom panel: immunofluorescence (100X). Scale bar represents 25 μm