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Κυτταρογενετική μελέτη της επίδρασης της μελατονίνης σε συνδυασμό με ιρινοτεκάνη σε καλλιέργειες κυττάρων ανθρώπου (Bachelor thesis)

Μήλιος, Κωνσταντίνος

The experimental procedures and the observation of the results for the following bachelor thesis were conducted at the Laboratory of Genetics of the Department of Medicine of Democritus University of Thrace, under the supervision of Professor Theodore S. Lialiaris. The purpose of this research is to study the effects of melatonin (C13H16N2O2), on cultures of normal human peripheral lymphocytes (in vitro), when the substance is used alone and in combination with the anticancer, antineoplastic drug camptothecin / irinotecan (CPT), which is a poison of the DNA topoisomerase and also is used in cancer treatment of gastrointestinal tumors. From the study of the available scientific bibliography, the hormone, aside of its natural function, which is mostly the regulation of sleep patterns, is also able to demonstrate other beneficial attributes, because of its many different anticancer mechanisms against a lot of cancer types (mainly neoplasm). From the above we understand that melatonin is a very interesting biological molecule. The results considering the effects of melatonin come from the usage of the Sister Chromatid Exchanges – SCEs method which indicates the number of DNA lesions. As it already mentioned above, CPT is also used in the experiments of the current study, which because of it’s mechanism of action increases the number of SCEs observed under the optical microscope. So CPT could be considered a good guideline for the determination of melatonin’s way of action. Aside of SCEs, multiplication rate index (MRI) and the mitotic index (MI) are also being studied for the factors mentioned above in the following matter: Firstly the melatonin effects on the chromosomes of human peripheral lymphocytes for the concentrations of 100μM and 300μM, have been studied and determined for all the three indexes mentioned above (MSCEs/MRI/MI), and then an attempt for the confirmation of melatonin’s cytoprotective attribute has been made along with the examination of possible synergistic action with CPT when melatonin is been placed into cultures where the antineoplastic factor was present. The results show that melatonin manifests genoprotective action even in very small dosages, that the hormone isn’t toxic for the cells even in relatively high dosages and that there are indications of reduction of MRI and MI without a very significant statistical difference on the cell cycle of the lymphocytes.