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Publisher Summary This chapter discusses provides an overview of normal and transformed cells in vitro . The development of culture techniques over the past few decades has enabled investigators to study different cell lines under identical conditions. As malignant cells in vivo are generally exposed to the same environmental milieu as their normal counterparts, a comparison of normal and malignant cells in vitro should provide useful information concerning the nature of cancer. To try to pinpoint the basic lesion, cells that are as similar as possible in other respects are obviously desirable. Transformed cells have proved to be just that. Viral infection of cultured cells leads to a permanent change such that the extent of growth in vitro is no longer subject to the same restrictions as before. As a result, transformed cells do not cease growing when they reach confluency, but pile upon, or rather below, each other in layers. Cells transformed with carcinogenic chemicals behave in a similar manner with respect to growth. Suggestions that the cell periphery plays a role in the altered growth of transformed cells are the result of an accumulation of data implicating the cell surface in the control of growth in vitro . |
