Immunohistochemical staining of POU2F3 in cervical samples from the tissue microarray. (a) Strong staining of POU2F3 in the cytoplasm of normal cervical epithelium above the basal cells ( × 40). (b) Intermediate staining in cervical intraepithelial neoplasias (CIN) 1 ( × 40). (c) Diminished staining in CIN 3 ( × 40). (d) Absent POU2F3 expression in invasive squamous cervical cancer (CC) ( × 40). (e–h) POU2F3 staining in the reserve cells of normal and low-grade lesions ( × 40).