Virus Transformation as a Function of Age, Differentiation and Hereditary Factors

Abstract

Neoplastic transformation of cell cultures has become a powerful tool to analyze the multiple steps involved in carcinogensis. Such in-vitro transformation of mammalian cells has been shown to occur after exposure to DNA- or RNA-oncogenic viruses, ionizing irradiation and chemical carcinogens (1–4). In most instances, dispersed monolayer cultures of freshly explanted cell strains or established cell lines have been used for such assays. Multiple parameters have been defined to assess in-vitro transformations (5). Much less precise information is available for cultures of differentiated cells or embryonal, fetal or neonatal organ cultures and their responses to carcinogenic stimuli. In particular, the interrelationship between the differentiated state of a target organ and susceptibility to carcinogenesis remains largely unexplored. Even the in-vitro responses of dispersed cells derived at various ages from the host deserve further attention if a correlation between potential target cells and host age is to be explained at the mechanistic level.