Acta Medica Medianae (Apr 2005)
THE EFFECT OF ASCORBIC ACID ON PATHOHISTOLOGICAL TUMOR CHARACTERISTICS AND PHENOTYPE CHARACTERISTICS OF LYMPHOCYTES DURING THE DEVELOPMENT OF EXPERIMENTAL MAMMARY CARCINOMA IN MICE
Abstract
TIn our previous study we demonstrated that high doses of ascorbic acid prolonged the survival of mice with experimental mammary carcinoma. In this work we studied, ussing the same model, pathohistological characteristics of the tumor and phenotypic changes of lymphocyte subsets in the spleen. Experiments were performed on CBA/H mice. The growh of experimental tumor was induced by injection of mammary adenocarcinoma cells intramuscularly at the femoral region of mice. The animals were divided into control group and three experimental groups (I, II and III). Mice from experimental groups were treated peroraly with 10, 100 and 1000 mg/kg body mass (b.m.) of ascorbic acid, respectively, whereas control mice received physiological saline. Mice were sacrified after 7, 14 and 21 days from the beginning of the experiment. Total tumor mass and its pathohistological characteristics, spleen mass and cellularity as well as relative and total numbers of T cells, B cells and T cell subsets (CD4+ and CD8+) in the spleen, were analyzed. High doses of ascorbic acid decreased tumor mass, stimulated proliferation of fibroblasts and formation of capsula arround the tumor, induced tumor necrosis and increased the number of tumor infiltrating lymphocytes. Changes of lymphocyte subsets and their numbers varied depending on the applied dose of ascorbic acid and the time elapsed following tumor induction. The most prominent changes, manifested by an increase in the number of CD4+ T cells were observed on the 14th day in II experimental group. Our results suggest that the beneficial effect of ascorbic acid on experimental tumorogenesis in our model was the consequence of its influence on the tumor and on the immune system.