Cancer research has identified several oncogenes, but the biological meaning of their mutations or altered expression levels as well as the interactions between different oncogenes are usually not immediately clear and require extensive research. Depending on the context, mutations and up- or down-regulation of proteins will or will not lead to the modulation of one or more of their functions and teach us more about their significance in Cancer. Among the most important oncogenes is the ATP-dependent RNA helicase DDX3.
One of the factors that contributed to the discovery of the role of DDX3 overexpression in cancer was the research on the known oncogenic effects of tobacco smoke. It was discovered that Benzopyran and Benzopyran Diepoxide (BPDE) which are Polycyclic Aromatic Hydrocarbons present in cigarette smoke, activated DDX3 expression and that this activation, in turn, promoted the growth, proliferation and neoplastic transformation of breast epithelial cells. Since then DDX3 overexpression has been verified in various forms of cancer, among which the most malignant types of Breast, Lung and Prostate Cancer, just to name a few. Further investigation is still going on with several academic groups worldwide studying this subject.