Table 1.

Epigenetic instability mediating evasion of growth suppressors.

type of cancer	frequency of promoter hypermethylation	reference
pancreatic adenocarcinoma	24.6%	[62]
oesophageal squamous cell carcinoma	81.7%	[41,42]
melanoma	25.9%	[63]
Burkitt's lymphoma	72.5%	[64]