Page 72 - SDIR5 Abstract book 21 12 2021.

POSTER PRESENTATIONS

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Ursodeoxycholic acid influences antioxidative capacity in human breast adenocarcinoma cell
line through Nrf2-dependent axis

1
Stanimirov Bojan , Stankov Karmen , Marko Dević , Pavlović Nebojša , Đanić Maja , Sekeruš Vanesa ,
1
2
1
1
3
Mikov Momir 3
1 Department of Biochemistry, Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia
2 Department of Pharmacy, Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia
3 Department of Pharmacology, Toxicology and Clinical Pharmacology, University of Novi Sad, Faculty of Medicine,
University of Novi Sad, Novi Sad, Serbia

Background: The transcription factor, nuclear respiratory factor-2 (NRF2) is one of the main orchestrators
of the cellular antioxidant response. The main objective of this in vitro study is to analyze the effects of
ursodeoxycholic acid on the cytotoxic activity of doxorubicin, and the expression of NRF2 and antioxidant
enzymes at the transcription level. Material and methods: MCF-7 cells were incubated for 24 h in a medium
containing doxorubicin alone (0.25µM) or in combination with ursodeoxycholic acid (50µM). Cytotoxicity
was determined using the MTT assay, whereas gene expression was determined using RT-qPCR method
with beta-actin as a reference gene. Gene expression was analyzed using comparative Ct method, and
statistical analysis was performed using one-way Anova and Tuckey’s post-hoc test. Results: Incubation of
MCF-7 cells with doxorubicin and ursodeoxycholic acid resulted in an increase in cytotoxicity compared to
the group of cells incubated with doxorubicin only (p=0.005). Treatment of cells with doxorubicin
significantly reduced the expression of NRF2, SOD, and GR compared to the control group (p<0.001;
p<0.001; p=0.002, respectively). In the co-treated cells, the expression of NRF2 was also significantly
reduced (p=0.004), however, the expression of SOD and GR was highly statistically significantly reduced
(p<0.001) compared to the group of cells incubated with doxorubicin only. Conclusion: Ursodeoxycholic
acid and doxorubicin synergistically increased cytotoxicity in the MCF-7 cell line, by reducing the expression
of NRF2, and its downstream targets, SOD and GR at the transcription level, aggravating redox homeostasis
in malignant cells.
Key words: oxidative stress, bile acid, breast adenocarcinoma, doxorubicin, apoptosis

Acknowledgements: Supported by the Ministry of Education, Science and Technological Development,
Republic of Serbia, Grant III41012, and Project of special interest for sustainable development in the
Autonomous Province of Vojvodina No. 142-451-2283/2021-01/02

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