Animals treated with CIN (100 mg/kg) or N-acetylcysteine (NAC, 750 mg/kg) showed a reduction in the MPO activity of 59.4% (515.0 ± 91.8 mDO/g of tissue) and 65.5% (438.0 ± 152.0 mDO/g of tissue) compared to the injured control group (Fig 1D). This evidence concerns the gene MPO and cervical squamous intraepithelial neoplasia.