2 The Culture of Mammalian Cells

Abstract

CELL CULTURE
Since the earliest days of experimental cancer research, attempts have constantly been made to simplify the study of the disease by cultivating normal and cancerous cells and tissues outside the organism. Comparison of normal and cancerous cells in culture, it has been hoped, would lead to the elucidation of their essential differences.

But cancer is a disease of whole organisms. It is not the tumour cells that are diseased, but their bearer whose otherwise normal life is disrupted by the presence and multiplication of the tumour cells. In concentrating on model systems—cultivated cells and the tumour viruses which infect them—cancer researchers have been obliged to make the assumption, usually unspoken, that neither cancer cells nor normal cells change when they are cultivated. Otherwise, their discoveries might well be applicable only to cultivated cells, and not to the diseased organism.

In discussing the strategy of science, Bernal points out an essential difference between discovery and problem-solving. “The essential feature of a strategy of discovery lies in determining the sequence of choice of problems to solve. Now it is in fact very much more difficult to see a problem than to find a solution for it. The former requires imagination, the latter only ingenuity.” (Bernal, 1971).

Two model systems have come to dominate cancer research: cell culture and transformation by tumour viruses. The assumption of relevance is still being tested, but we believe that, in Bernal’s terms, these model systems have already served us well: they have permitted...