PAX9 is reportedly involved in cell proliferation, migration, and apoptosis in oral squamous cell carcinoma, cervical cancer, and oro-esophageal epithelial cancer [[42], [43], [44]], and is an essential transcription factor in tooth development and palate morphogenesis that can modulate the expression of BMP4 expression [45,46]. The gene discussed is BMP4; the disease is oral cavity squamous cell carcinoma.