PECULIARITIES OF CHANGES IN POLYAMINS LEVELS IN THE DYNAMICS OF PARENTAL AND CISPLATIN-RESISTANT GUÉRIN’S CARCINOMA GROWTH

Abstract

The results of many studies have shown that intensification of polyamine synthesis (PAs) and its accumulation in tumor tissues as well as in blood, urine and spinal-cerebral fluid is a characteristic of human and animals’ malignant tumors. There are some evidence that effective cytostatic treatment is accompanied by a decrease in PA content in tumor tissue and in the biological fluids of experimental animals and cancer patients. Meanwhile, the assumption that detection of PA in biological fluids can be used in monitoring the treatment process remains to be elucidated. Aim: to investigate the levels of PAs in the tumor tissue of parental and cisplatin-resistant substrains of Guérin’s carcinoma as well as in the peripheral blood of tumor-bearing rats in the dynamics of the tumor growth. Object and methods: Wistar rats, parental and cisplatin-resistant substrains of Guérin’s carcinoma, peripheral blood of tumor-bearing rats. PA (spermine (Spn), spermidine (Spd), acetylated form of spermidine (Acetyl-Spd) and putrescine (Put)) content in the tumor tissue and peripheral blood was determined by high pressure liquid chromatography. The statistical analysis of the results was performed according to generally accepted methods of variation statistics. Results: as parental Guérin’s carcinoma progresses (exponential phase), the level of Spd, Acetyl-Spd, Spn in tumors tissues as well as Spd/Spm ratio were increasing while the level of Put was declining. Later on, the levels of all tested PA fractions decreased. In the exponential phase of cisplatin-resistant carcinoma growth, the levels of Spd, Put and the Spd/Spn ratio were increasing, while the levels of Spn and Acetyl-Spd were decreasing. As compared to the corresponding data of the parental strain of the Guérin’s carcinoma, the level of Put in tissue of cisplatin-resistant carcinoma remained higher in all periods of the study, while the levels of Spd and Spn during the exponential phase were lower. In both groups of tumor-bearing animals, changes in PA levels in the peripheral blood correlated with their levels in tumor tissue. Conclusions: there was shown, that cisplatin-resistant substrain of Guérin’s carcinoma is characterized by changes in PA metabolism compared to the parental strain. The obtained data on the peculiarities of PA levels dynamics in tumor tissue and peripheral blood of experimental animals depending on the sensitivity of tumors to cytostatic drug can be further used in clinical settings to monitor the effects of chemotherapy on the tumor process.