Uptake of radiolabeled anticancer drug on tumor cells and DNA interaction

The aim of our thesis is to label Topotecan (TPT) which is an anticancer drug, with 131I to investigate biopotential of lung cancer as in vitro. Topotecan was labeled with 131I with iodogen method and its quality control was determined using thin layer radiochromatography and paper electrophoresis methods. In result of the quality control experiments it is stated that TPT was labeled with high efficiency (94.1 ± 5.9 %). IC50 values of TPT in lung cancer cells and healthy cells were determined as 14.82 and 59.3 µM respectively at end of cytotoxicity assays. The uptake of 131I-TPT in A-549 cell line is higher than WI-38 cell line. This is show that radiolabeled TPT is spesific for lung cancer. In our study the optimum time of medicine-DNA interference was determined with using single use electrochemical sensors. As a control group, the behavior of 131I and TPT, their interferences with healthy/ unhealthy DNA were investigated and the changes of the signals due to charge transfer was that produced by electrochemical reactions were investigated with electrochemical impedance spectroscopy and it was seen that the interference of 131I-TPT in cancer DNA is higher than the other inteferences. In the experiments performed with 131I-TPT, the uptake of 131I-TPT in lung cancer and DNA interactions by electrochemical method were investigated, 131I-TPT is promising in terms of a new lung cancer nuclear imaging agent.