Lower expression of NAB2 (p = 0.0023), CYP27A1 (p = 0.0016), NPIPB4 (p = 0.0059), MAOB (p = 0.0009), and SIAE (p = 0.037) for the OSCC vs. non-tumor group The combination of two mRNAs (CYP27A1 + SIAE) and lower expression of MAOB-NAB2 mRNAs showed clinical value in the diagnosis of early stages of OSCC, especially in patients under 60 years of age. The gene discussed is CYP27A1; the disease is neoplasm.