title: Thymidylate synthase levels in tumor biopsies from patients with colorectal cancer.
abstract: Catalytic activity and FdUMP binding characteristics of thymidylate synthase (TS) were determined in 22 tumor biopsies of patients to be treated (15) or just treated (7) for colorectal cancer with 5-fluorouracil and leucovorin. In 19 samples both parameters could be determined and were found to represent a wide range (15-20 fold). High values of activity correlated with no response, but low values of binding or activity were found in responders as well as in non-responders. It is concluded that the determination of parameters related to TS function is feasible in tumor biopsies and its relevance for clinical management deserves further study.
authors.affiliation: Department of Internal Medicine, University Hospital Groningen, The Netherlands.
authors.forename: N H
authors.initials: NH
authors.lastname: Mulder
authors.forename: H
authors.initials: H
authors.lastname: Timmer-Bosscha
authors.forename: G J
authors.initials: GJ
authors.lastname: Meersma
authors.forename: R C
authors.initials: RC
authors.lastname: Verschueren
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D015179:Colorectal Neoplasms / Q000188:drug therapy / Q000201:enzymology* / Q000473:pathology; D005260:Female; D005468:Fluorodeoxyuridylate / Q000378:metabolism; D005472:Fluorouracil / Q000627:therapeutic use; D006801:Humans; D002955:Leucovorin / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D013940:Thymidylate Synthase / Q000032:analysis / Q000378:metabolism*
chemical_list: D005468:Fluorodeoxyuridylate; D013940:Thymidylate Synthase; D002955:Leucovorin; D005472:Fluorouracil