Concepts in malignant transformation.

The precise biochemical nature of malignant transformation remains elusive. This article reviews some of the current theories of oncogenesis and aims to synthesize these concepts into a possible schema for the origins of malignant transformation, using a cell-programmed origin for neoplastic progression. It is proposed that cell transformation in malignancy is initiated by injury but finds ultimate promulgation through cellular, self-determined, epigenetic events. Explanations for this arrangement are sought in evolutionary models and our knowledge of cell biology. The proposed mechanisms have not been experimentally validated, but will hopefully stimulate further research.