Investigations on Cygb's tumour suppressing activity reported in 2006 have shown that most cancer cells have a reduced expression of Cygb, with a dramatic decrease (70%) of cytoglobin expression reported in tylosis with oesophageal cancer (TOC) [12, 44, 45]. The gene discussed is CYGB; the disease is palmoplantar keratoderma-esophageal carcinoma syndrome.