CCNE1 and neoplasm: Our in vivo findings suggest that in human oesophageal SCC, cyclin D1 and cyclin E and their functional partners, CDK4 and CDK2, often exhibit dysregulated overexpression in many cases, and that tumours with simultaneous expression of cyclin D1 and CDK4 are frequently associated with venous invasion and have a worse prognosis, statistically.