Change in cell membrane permeability, and composition and properties of hexokinase during induced carcinogenesis]

The isoenzyme hexokinase (HK) spectrum from normal rat large intestinal mucosa consisted of 3 isoenzymes. In tumours of this localization induced by 1,2-dimethylhydrazine there proved to be a lack or marked decrease in the most rapid anodic isoenzyme. Only one HK isoenzyme was found in the metastases. Km (glucose) for tumour HK was 2--3 times lower than for normal intestinal HK; the HK activity was detected in the serum from the 1st month of the carcinogenic administration, and by the 5th month it was found in 80% of the tumour-bearing animals. No serum HK activity was ever found in control rats.