The IMP and GMP concentrations were compared after treatment with tiazofurin alone and in combination with 5-hexyl-2'-deoxyuridine (HUdR) in 3LL-HH adenocarcinoma in vivo. The elevation in IMP/GMP ratio indicating guanylate depletion and increase of inosine-5'-monophosphate concentration showed a dose dependence and was the highest at the 7th hour after treatment with tiazofurin. HUdR application alone caused only a modest change in the nucleotide concentration of LL-HH tumour. However the rise of IMP hut not the reduction of guanylate concentration induced by tiazofurin was remarkably mitigated by HUdR treatment without affecting the antitumour potency of tiazofurin. Thus HUdR showed modifying activity on some of the tiazofurin-induced changes in nucleotide metabolism which appeared not to be associated with the antiproliferative activity of tiazofurin. It follows that reduced GMP concentration and not the elevation of IMP/GMP ratio could predict therapeutic responses to tiazofurin.
|Number of pages||4|
|Publication status||Published - Jan 1 1992|
- 3LL tumour
ASJC Scopus subject areas
- Cancer Research