PS064
Analysis of combined impact of doxorubicin and menadione on human leukaemia Jurkat T cells
Alexandru Ionut Duta, , Ioana Teodora Tofolean, Ramona Madalina Babes, Constanta Ganea, Irina Baran
“Carol Davila” University of Medicine and Pharmacy, Department of Biophysics, Bucharest, Romania

Aim: The anti-proliferative effect and the mechanism of action of doxorubicin(DOX) in combination with menadione(MD) were studied in Jurkat T cells, a model for acute lymphoblastic leukaemia (ALL).

Introduction: Doxorubicin is a well-characterized and successful antineoplastic drug commonly used in various cancer treatments, including ALL. Menadione has proven a strong pro-apoptotic effect in Jurkat cells.1–3

Methods: Cell cycle, apoptosis/necrosis and the oxidative status were assessed by flow cytometry on propidium iodide, Annexin V-FITC/PI and CM-H2DCFDA/7-AAD labelled cells, respectively.

Results: Oxidative stress induced within 4h by MD (IC50=11.5μM) was reduced in the presence of 500nM DOX (IC50=22.0μM). After treatments of 18h, DOX induced cell cycle arrest displaying a trimodal distribution; successive G2/M, S and G0/G1 blockage was produced with an IC50 of 49nM, 464nM and 1866nM, respectively, whereas in the presence of 7.5μM MD, increasing levels of DOX mainly induced S-phase arrest. Within 18hours of exposure, DOX induced apoptosis in a biphasic dose-dependent manner (Kd=335nM and 3.29μM, respectively). Addition of 7.5μM MD enhanced apoptosis at <300nM DOX, but reduced cell death at higher levels of DOX. However, 48h after drug removal the apoptotic rate was considerably higher in cells exposed to DOX:MD, which also showed consistent fractions of early apoptosis (up to 44%). The efficacy of DOX was doubled by MD(Kd=46.5nM in the presence, and Kd=99nM and 143nM in the absence of MD).

Conclusion: Data indicate that clinically relevant levels of MD and DOX in combined treatments can exert considerable cytotoxic impact on Jurkat cells, via cell cycle arrest and apoptosis induction. These findings could encourage new therapeutic strategies to improve the therapeutic index of doxorubicin in ALL treatments.

Acknowledgements: This work was supported by a fellowship of the Romanian Ministry of Education, UEFISCDI, for Young Researchers, project number 8/2016.

References
1
I. Baran
Cell Biochem Biophys, 58 (2010), pp. 169-179 http://dx.doi.org/10.1007/s12013-010-9104-1
2
I. Baran
Leukemia Res, 38 (2014), pp. 836-849
3
I.T. Tofolean
Pharmacol Res, 103 (2016), pp. 300-317 http://dx.doi.org/10.1016/j.phrs.2015.12.013

Warning: Invalid argument supplied for foreach() in /var/www/html/includes_ws/librerias/html/item.php on line 1203

Open Access

Creative Commons License
Porto Biomedical Journal is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

+ info