COMPARATIVE STUDIES ON THE METABOLISM OF NORMAL AND MALIGNANT CELLS

Abstract

Warburg and his associates have reported a series of studies on the metabolism of malignant tissues as compared to that of normal tissues. 1 Their first observation, that respiration was considerably less in the Flexner-Jobling rat carcinoma than in normal rat tissues, led them to conclude that the Ringer's solution in which the studies were made lacked suitable material for combustion. Later investigation revealed that the addition of glucose inhibited even the small amount of respiration which took place in the tumor tissue suspended in plain Ringer's. The explanation of this was found to be the fact that lactic acid was produced by glycolysis in sufficient amounts to halt the respiratory exchange. On the other hand glucose failed to influence the respiration of normal tissues such as liver and kidney cells and they were found to produce only very minute amounts of lactic acid. This observation led to a quantitative study of the glycolytic activity of malignant cells.