[Metformin impact on purine metabolism in breast cancer].

Large-scale epidemiological and clinical studies have demonstrated the efficacy of metformin in oncology practice. However, the mechanisms of implementation of the anti-tumor effect of this drug there is still need understanding. In this study we have investigated the effect of metformin on the activity of adenosine deaminase and respectively adenosinergic immunosuppression in tumors and their microenvironment.

Effect of 5-Fluorouracil on Thymidine Phosphorylase Activity in Model Experiment.

Variations in thymidine phosphorylase activity in rat liver were studied in 1, 3, 6, 12, and 24 h after intraperitoneal bolus injection of 5-fluorouracil. Enzyme activity was measured by HPLC. A 2-fold decrease in enzyme activity was observed 3 h after 5-fluorouracil administration and persisted for 12 h.

The influence of 5-fluorouracil on activity of thymidine phosphorylase in gastric adenocarcinoma and normal adjacent tissue.

Unlabelled: The aim of the present study was to evaluate the change of thymidine phosphorylase (TP) activity in gastric adenocarcinoma and adjacent tissue upon the intraarterial administration of 5-fluorouracil (5-FU). Matherials and methods: The specimens of tumor and adjacent tissue were obtained by surgical operation on 36 patients (20 men and 16 women aged from 38 to 82 years) with gastric adenocarcinoma (stages II-IV). 5-FU was administered in the bolus dose to the gastroepiploic artery 2-60 min before the tumor resection.

[Distribution of 5-fluorouracil between lymphocytes and blood plasma].

In blood plasma of 8 healthy volunteers with resuspended lymphocytes incubated with 5-fluorouracil (5-FU) the drug distribution between cells and liquid was assessed by means of HPLC. Rapid accumulation of 5-FU in lymphocytes was proved (the drug concentration on the 3-rd minute is 2.5-fold higher than in plasma) as well as the absence of temporal changes of 5-FU content both in lymphocytes and blood plasma during 30 minutes of experiment.