IL1B and intraepithelial neoplasia: Finally, to estimate the clinical relevance of our in vitro data, initial validation of human biopsy material shows a progressive loss of IL-1β, as monitored both by immunohistochemical staining (Fig. 6A) and quantitative RT-PCR of tissue samples (Fig. 6B), representing different grades of intraepithelial neoplasia (CIN I–III) and cervical cancer.