Some evidences of molecular epidemiology in cancer research

Molecular epidemiology of cancer has been developed along with rapid advances in molecular carcinogenesis, introducing new approaches to etiology and prevention of cancer. First, research activities in Japan are briefly reviewed in this issue focusing on studies of genetic susceptibility, DNA damages, and immunological defense. Then we make an estimation of age periods of initiation for several cancer on the basis of multistaged carcinogenesis. The results are discussed in relation to strategies of cancer prevention in molecular epidemiology, introducing our trials previous and on-going as examples.