Altered Expression of ezrin, E-Cadherin and β-Catenin in Cervical Neoplasia
High-grade cervical squamous intraepithelial lesions (CIN) as well as squamous cell carcinoma and adenocarcinoma of the cervix are associated with persistent high-risk human papillomavirus (HPV) infection. A number of cellular events play a role in HPV pathogenesis and in the development of cervical lesions, including alterations in cell adhesion and motility. The crucial plasma membrane - cytoskeleton linker protein ezrin of the Ezrin-Radixin-Moesin (ERM) protein family is involved in the regulation of cell morphology, cell adhesion and invasion. Based on our previous work on ERM proteins we sought out to study the expression of ezrin in cervical premalignant lesions. We also studied the expression of E-cadherin and β-catenin, which play an important role in epithelial cell adhesion. We observed intensifying expression of ezrin along with progressing grade of neoplasia. Ezrin staining was found to colocalize with p16 staining in high-risk HPV associated lesions. Expression of E-cadherin and β-catenin was found to be altered along with the severity of the lesion, similar to ezrin. Enhanced expression of ezrin in cervical HPV associated lesions suggests a role in the development of cervical neoplasia and cancer. Further clinical evaluation should reveal the feasibility of ezrin as a biomarker for the progression of cervical lesions. Keywords: CIN, ezrin; HPV, papillomavirus.
- [Show abstract] [Hide abstract]
ABSTRACT: The oncoprotein E7 from human papillomavirus-16 (HPV-16 E7) plays a pivotal role in HPV postinfective carcinogenesis, and its physical interaction with host cell targets is essential to its activity. We identified a novel cellular partner for the viral oncoprotein: the actin-binding protein gelsolin (GSN), a key regulator of actin filament assembly and disassembly. In fact, biochemical analyses, generation of a 3D molecular interaction model and the use of specific HPV-16 E7 mutants provided clear cut evidence supporting the crucial role of HPV-16 E7 in affecting GSN integrity and function in human immortalized keratinocytes. Accordingly, functional analyses clearly suggested that stable HPV-16 E7 expression induced an imbalance between polymeric and monomeric actin in favor of the former. These events also lead to changes of cell cycle (increased S phase), to the inhibition of apoptosis and to the increase of cell survival. These results provide support to the hypotheses generated from the 3D molecular interaction model and encourage the design of small molecules hindering HPV-induced host cell reprogramming by specifically targeting HPV-16 E7-expressing cells.
- [Show abstract] [Hide abstract]
ABSTRACT: Ezrin, a member of the ezrin/radixin/moesin (ERM) protein family, plays a pivotal role in tumor invasion and metastasis. This study is aimed to investigate the clinicopathological significance of upregulated ezrin protein expression in uterine cervical cancers. Immunohistochemical staining of ezrin protein was performed on uterine cervical cancer specimens from 235 patients. For comparison, 239 cases of cervical intraepithelial neoplasia (CIN), 17 cases of cervical glandular intraepithelial neoplasia (CGIN) and 52 normal cervix samples were also included. qRT-PCR was performed on fresh tissues to detect ezrin mRNA expression levels. HPV infection statuses were genotyped by oligonucleotide microarray, and 10-year survival rates were calculated using the Kaplan-Meier method for 109 cervical cancer patients. Apical membranous distribution of ezrin protein was only observed in normal cervical glands, while perinuclear staining was only observed in cervical cancers. Strong cytoplasmic and diffuse localization of ezrin were frequently seen in the cervical cancers compared with the normal counterparts. Furthermore, this strongly positive ezrin expression was significantly higher in cervical cancers than in CIN, CGIN, and normal cervical epithelia. Ezrin overexpression was closely related with poor differentiation, late stage, and lymph node metastasis. Additionally, ezrin overexpression was associated with lower 10-year survival rate for patients with early stage cervical cancer, but not for patients with advanced stage. Aberrant localization and overexpression of ezrin might be an independent effective biomarker for prognostic evaluation of cervical cancers.
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.