CIN is linked to the mutation of tumor suppressor genes, including adenomatous polyposis coli (APC), P53, Mothers Against Decapentaplegic homolog 2 (SMAD2), SMAD4, deleted in colorectal cancer (DCC), and oncogenes Kirsten rat sarcoma virus (K-ras) and β-catenin [1, 7, 8]. Here, SMAD2 is linked to cervical squamous intraepithelial neoplasia.