Lactic Dehydrogenase Production in Tissue Culture of Normal, Transformed, and Malignant Human Cell Lines.

Abstract

Normal, malignant, and transformed cell lines were studied for variations in 3 different enzyme activities; glutamic-oxalacetic and glutamic-pyruvic transaminases and lactic dehydrogenase (LD). Only the LD activity changed during the growth period. The enzyme activity both in the cells and in the fluid bathing them was greatly increased in the malignant cell lines and in 2 transformed lines, in contrast to the normal cell lines and the conjunctiva cell line where large quantities did not appear in the media. The increase in LD activity was related to the cellular growth rate rather than a characteristic of the cell, since the normal cells in most instances contained more enzyme activity per cell than the malignant ones.