Immunohistochemical expression of laminin-5 in cervical intraepithelial neoplasia.

Laminin-5 is an attachment protein for epithelial cells. Several studies of a variety of cancers have reported increased expression of laminin-5 in carcinoma in situ and invasive cancer. This study was designed to investigate the correlation between the grade of cervical intraepithelial neoplasia and the immunohistochemical expression of laminin-5 in the cytoplasm and in the basement membrane underlining dysplastic squamous cells. We used immunohistochemical methods to stain paraffin-embedded sections of cervical cone biopsies with a monoclonal antibody specifically targeting the 2-chain of human laminin-5 protein. The study sample included 175 slides: 7 normal cervical epithelium, 36 lesions of mild dysplasia, 50 lesions of moderate dysplasia, 81 lesions of severe dysplasia, and 1 invasive squamous cell carcinoma. We found a statistically significant correlation between the grade of cervical intraepithelial neoplasia and laminin-5 immunoreactivity in the cytoplasm (P < 0.01) and in the basement membrane (P = 0.03) by use of the Wilcoxon rank-sum test. According to previously published reports we confirmed with a higher number of cases a correlation of laminin-5 expression in the cytoplasm and/or basement membrane and grade of dysplastic lesion in the cervical epithelium. This study warrants further investigations with special interest to follow-up to investigate whether laminin-5 is a marker to predict the risk of progression of cervical intraepithelial neoplasia lesions.