The results of this experiment revealed that PAX1 nuclear expression was weak in normal cervix, moderate in low-grade squamous intraepithelial lesion (LSIL), strongest in high-grade squamous intraepithelial lesion (HSIL), but weak in invasive cancer cells (Fig. 1A,B). This evidence concerns the gene PAX1 and squamous cell intraepithelial neoplasia.