In basal keratinocytes, 100% (12/12) of normal biopsies showed constitutive expression of TNF-α, a strong stimulator of LCs which was lacking in a number of CIN samples including 87% (20/23) of CIN 1 and 67% (12/18) of CIN 2 (91). Here, TNF is linked to cervical squamous intraepithelial neoplasia.