Abstract
Xanthine oxidase was decreased 2- to 10-fold in all examined rat hepatomas irrespective of the malignancy; growth rate and degrees of histological differentiation of the neoplasms. The affinity to substrate (KM=6-8 muM) and the pH optimum (8.0) of the liver and hepatoma enzymes were the same. The reprogramming of gene expression, as manifested in the decreased activity of this key purine metabolizing enzyme, appears to be specific to neoplastic transformation. Since glutamine PRPP amidotransferase activity was increased but the opposing enzyme, xanthine oxidase, was decreased in all the hepatomas, the reprogramming of gene expression results in an imbalance that favors synthesis against catabolism. This enzymatic imbalance should confer selective advantages to the cancer cells.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
