TFPI2 is a tumour suppressor gene that is known to be hypermethylated in many tissue types including the gastrointestinal tract36–38 and is one of the top 20 genes for detecting early stage oral squamous cell carcinoma.39 Its tumour suppressor properties are due to its inhibitory effects on protease activity, thus protecting the tumour cell matrix from degradation and counteracting malignant cell invasion and metastasis. This evidence concerns the gene TFPI2 and oral cavity squamous cell carcinoma.