Effects of vinblastine on blood flow of solid tumours in mice

Abstract

The aim of our study was to determine the effects of low doses of Vinblastine (VLB) on tumor growth and time course of blood flow changes in solid tumors of mice. Two murine tumors were used in the study; EAT carcinoma and SA-1 fibrosarcoma, syngeneic to CBA and A/J mice, respectively. Mice were treated with intraperitoneal injection of 2 different VLB doses when the tumors reached 6 mm in diameter. Antitumor effectiveness was determined by tumor growth delay assay. Tumor blood perfusion changes were assessed by means of Laser Doppler flowmetry. The antitumor effectiveness of both doses in SA-1 tumors was minimal, resulting in 2.0 days tumor growth delay. The antitumor effectiveness in EAT tumor was also minimal, but dose dependent; the lower dose induced 1.1 tumor growth delay, while the higher dose resulted in 2.1 tumor growth delay. This higher dose of 50 µg VLB produced statistically significant and highly reproducible decrease in blood flow. The maximum effect was reached 1.5 hours after the treatment. The lower doses did not significantly affected tumor blood perfusion. Our data demonstrate that VLB at the dose that minimally affect tumor growth, have a significant effect on tumor blood perfusion.