Phosphomannose Isomerase Activity in a Spectrum of Normal and Malignant Rat Tissues.

Publisher Website
Google Scholar
Abstract
Since earlier workers had presented data indicating active entry of mannose into glucose metabolic pathways, studies were conducted to determine (a) whether tumors possessed phosphomannose isomerase (PMI), (b) to compare the PMI activity of malignant and normal tissues and (c) to determine whether PMI activity was altered during azo-dye carcino-genesis. The conversion of mannose-6-phosphate to fructose-6-phos-phate was used as the criterion for PMI activity. Primary hepatomas were induced by feeding 0.06% 3[image]-methyl-4-dimethylaminoazobenzene (3[image]-Me-DAB) in a semi-synthetic diet. PMI activity of Jensen sarcoma, Walker carcinosarcoma 256 and Flexner-Jobling carcinoma was compared to that of kidney, brain, muscle and spleen. The activity of the Jensen and Walker tumor was the same as that of kidney and brain, but was higher than that of muscle or spleen. The PMI activity of primary lesions induced with 3[image]-Me-DAB and the Novikoff hepatoma was equivalent to that of normal liver. A transplanted 3[image]-Me-DAB hepatoma was equivalent to that of normal liver. A transplanted 3[image]-Me-DAB hepatoma had PMI activity 2-fold higher than normal liver, while activity in liver tissue adjacent to primary hepatomas was approximately half that observed in liver.

This publication has 1 reference indexed in Scilit: