Hexosephosphate metabolism of tumour extracts

Abstract

No lactic acid is produced by extracts or cell suspensions of tumor tissue with glucose as substrate at 38[degree] or 52[degree] whether glutathione is added or not. Small yields of lactic acid are obtained from hexosediphosphate at 38[degree] and no increase is observed on addition of glutathione. At 52[degree] a considerable yield is obtained with hexosediphosphate which is increased by addition of glutathione. Dialyzed tumor extract will produce very little lactic acid from hexosediphosphate at 52[degree], but on addition of glutathione its activity is restored. Addition of kidney "antiglyoxalase" greatly reduces the lactic acid production of tumour extracts at 52[degree] and it is considered that at this temp. the glycolytic system proceeds by way of methyl glyoxal. The contrast between the glycolytic systems of extracts of muscle and of tumor is discussed.