Another study observed that salivary MMP-9 could be a critical diagnostic and prognostic biomarker for OSCC (analysis of covariance and multivariable linear regression, p<0.05), and MMP-9 decreased from 588.15 to 131.80 ng/mL after tumor surgery in 9 months (p<0.05) 83. The gene discussed is MMP9; the disease is neoplasm.