Investigation of the effects of plant phenolic oleuropein on expression levels of xenobiotic metabolizing enzymes along with potential cytotoxic and genotoxic impact on human colon cancer cell line HT-29


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Edebiyat Fakültesi, Biyolojik Bilimler Bölümü, Türkiye

Tezin Onay Tarihi: 2018

Tezin Dili: İngilizce

Öğrenci: EZGİ DURMUŞ

Danışman: Orhan Adalı

Özet:

Colon cancer is one of the major health problems causing malignancies and is frequently encountered in developed western countries. Today, in the treatment of colon cancer, several methods are used, mostly with adverse effects. In order to reduce the consequences of side effects usage of natural or artificial anti-cancer molecules is a serious topic in the cancer research area. Scientists began to perform research to find anti-carcinogenic phytochemicals and xenobiotics with anti-carcinogenic potentials. Until now, at least five thousands phenolic compounds have been described and oleuropein is one of the substantial phenolic compounds whose effects were determined on formation of cancer cells. In the light of this information, this study was aimed to identify potential oleuropein effects on colon cancer cell proliferation, DNA damage formation and protein expressions of CYP1A1, GSTM1 and NQO1 enzymes at in vitro level. In order to achieve goals of this study, HT-29 colon cancer cells were grown and treated with increasing oleuropein doses, and IC50 value was determined as 600 µM. Effects of oleuropein on DNA damage formation and protein expressions were studied by Comet assay and Western Blotting, respectively. Oleuropein treatment caused decrease in protein expression levels of CYP1A1, GSTM1 and NQO1 enzymes. Oleuropein also caused increase in DNA damages of the colon cancer cells in a dose dependent manner. In conclusion, the results of this study showed that oleuropein inhibits the proliferation of colon carcinoma cells by affecting the DNA damage formation and protein expression of CYP1A1, GSTM1 and NQO1 enzymes.