Genetic aspects of cancer.

摘要: The two basic premises upon which investigation of the malignant phenotype is based are that malignancy results via alterations in genetic material cell, and accumulation these occurs a multistep fashion. Early indication normal cellular genes were targets for mutation came from observation acutely transforming retroviruses contained abnormal copies (the protooncogenes), presence was required activity viruses [reviewed J. M. Bishop (1983)]. Over three dozen protooncogenes have been identified through transfection by retroviruses, gene transfection, homology to retroviral oncogenes (J. Bishop, 1985; ‘Rhim, 1988). These activated tend be dominant, their overriding allele. multistage hypothesis supported byin vitrostudies demonstrating conversion primary cells tumorigenic requires minimum cooperating (Land et al., 1983) epidemiological studies human cancer suggested seven steps before manifestedin vivo(Armitage Doll, 1954; Ashley, 1969b; Nordling, 1953).