From pathology to chemistry and back: James W. Cook and early chemical carcinogenesis research

During the 1920s, concerns over occupational cancers in the tar, coal-gas and synthetic dye industries stimulated investigations into the responsible carcinogenic agents. Chemical pathologist Ernest L. Kennaway and organic chemist James W. Cook at London's Cancer Hospital Research Institute were the first to identify pure carcinogenic coal-tar polyaromatic hydrocarbons. Cook, who joined Kennaway in 1929, synthesised and tested hundreds of compounds, seeking to identify the exact relationship between chemical constitution and cancer. This paper reviews Cook's research programme until the early 1940s, and the attempt of his collaborator, Cambridge biochemist Joseph Needham, to identify the biological basis of carcinogenesis. In this, they drew upon structural and functional analogies between recently discovered hormones and carcinogens. Cook established novel ways of studying chemical carcinogenesis, although conflicting empirical results and understandings of cancerous growth militated against the development of a coherent mechanistic theory.