title: Uridine phosphorylase in breast cancer: a new prognostic factor?
abstract: Uridine phosphorylase (UPase) is an enzyme that converts the pyrimidine nucleoside uridine into uracil. Upon availability of ribose-1-phosphate, UPase can also catalyze the formation of nucleosides from uracil as well as from 5-fluorouracil, therefore involved in fluoropyrimidine metabolism. UPase gene expression is strictly controlled at the promoter level by oncogenes, tumor suppressor genes, and cytokines. UPase activity is usually elevated in various tumor tissues, including breast cancer, compared to matched normal tissues and this induction appears to contribute to the therapeutic efficacy of fluoropyrimidines in cancer patients. In this review, we will discuss in detail the role of UPase in the activation of fluoropyrimidines and its effect on the prognosis of breast cancer patients.
authors.affiliation: Department of Medical Microbiology, Immunology, and Cell Biology, Cancer Institute, Southern Illinois University School of Medicine, Springfield, IL 62702, USA.
authors.forename: Ruilan
authors.initials: R
authors.lastname: Yan
authors.forename: Laxiang
authors.initials: L
authors.lastname: Wan
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Pizzorno
authors.forename: Deliang
authors.initials: D
authors.lastname: Cao
mesh_terms: D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000378:metabolism / Q000627:therapeutic use; D014408:Biomarkers, Tumor; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000201:enzymology*; D000069287:Capecitabine; D003841:Deoxycytidine / Q000031:analogs & derivatives / Q000378:metabolism; D004790:Enzyme Induction; D005260:Female; D005467:Floxuridine / Q000378:metabolism / Q000627:therapeutic use; D005472:Fluorouracil / Q000378:metabolism / Q000627:therapeutic use; D005786:Gene Expression Regulation; D006801:Humans; D051379:Mice; D011355:Prodrugs / Q000378:metabolism; D011379:Prognosis; D011744:Pyrimidinones; D016896:Treatment Outcome; D014543:Uridine Phosphorylase / Q000096:biosynthesis* / Q000378:metabolism*
chemical_list: D000964:Antimetabolites, Antineoplastic; D014408:Biomarkers, Tumor; D011355:Prodrugs; D011744:Pyrimidinones; D005467:Floxuridine; D003841:Deoxycytidine; D000069287:Capecitabine; D014543:Uridine Phosphorylase; D005472:Fluorouracil; C025034:doxifluridine