Potential effects of gamma irradiation on the stability and therapeutic activity of anticancer drug, doxorubicin

Cancer therapy has progressed dramatically in recent years. In order to decrease the dose and side effects of the anticancer drug, the therapeutic options for patients with cancer include increasingly complex combinations of chemotherapy and radiotherapy. This combination may cause overlapping interaction between the two types of treatment and affect the stability of the anticancer drug. In this study, the effect of gamma irradiation on the stability and therapeutic activity of one anticancer drug (Doxorubicin) was studied. For this purpose, doxorubicin drug characterized by two methods, at first, in-vitro study, before and after drug irradiation with different doses of gamma rays (2, 5, 20, 100 GY) which achieved through measuring the dielectric relaxation and absorption spectrum of drug solution. Secondly, in-vivo studies, where the unirradiated and the drug, which later exposed to gamma rays, were injected respectively into 6 groups of mice (3 mice in each group). The dielectric relaxation and absorption spectrum were studded for hemoglobin of the injected mice. The results for the in-vitro study indicate that the values of dielectric parameters show unnoticeable change for drug molecules before and after irradiation as compared with the control. The results for in-vivo study indicated an increase in the values of relaxation time and Cole- Cole parameter, that may as a result of changes in the conformational structure in hemoglobin molecules which may affect their properties and hence RBC's physiological functions. The absorption spectra of hemoglobin molecules show an increase in the amplitude of the characteristic bands with irradiation dose indicate an increase of the oxygen binding capacity with hemoglobin. It was concluded that combination between the drugs and gamma irradiation can be used as a powerful conjunction that may give us the benefit chemo and radiotherapy treatment.