Original ArticleTargeting cancer cells through antibiotics-induced mitochondrial dysfunction requires autophagy inhibition
Graphical abstract
Introduction
For the last 70 years, antibiotics have been used worldwide on an enormous scale [1]. Despite their profound clinical effectiveness, a growing body of compelling evidence has now shown that even at low concentrations some antibiotics may inhibit mitochondrial functions and lead to detrimental changes on both molecular and physiological levels [2]. Mitochondria are key organelles that have an essential role in the life and death of cells [3]. Having a double-membrane organization, mitochondria are thought to have evolved from the genus rickettsia bacteria but have lost the peptidoglycans as they no longer required to carry out respiration [4]. These organelles should be considered as weakly gram-negative or even gram-indeterminate and likewise many bacteria can be targeted by antibiotics. After being neglected for many years, this fact has brought some attention not only from scientists using antibiotics in their cellular and animal models but also from the clinicians, and especially from the pharmaceutical companies, planning drug repurposing in anticancer therapy [5].
Yet, the possible role of antibiotics in MDF is unclear and seems to be tissue- and cell line-dependent. The current study focuses on the elucidation of the roles of several commonly used antibiotics on mitochondrial functions. We show evidence of MDF in both normal and cancer cells treated with antibiotics. Moreover, antibiotics can increase ROS and trigger autophagy in both types of cells. However, antibiotics did not significantly affect survival as well as repopulation capacity of cancer cells, perhaps due to a glycolytic shift or activated autophagy. In turn, simultaneous treatment with antibiotics and inhibitor of autophagy largely reduced tumorigenic properties of cancer cells suggesting their combinatory application as potential anticancer strategy.
Section snippets
Chemicals and antibodies
Manitol, cat# M4125 purity >99.5, N-acetyl-cystein (NAC), cat# A7250 purity >99.5, sucrose, cat# S0389 purity >99.5, Na3VO4, cat#590088, purity >99.5, NaF, cat#S7920, purity >99.5, cat#D2510, purity >99.5, deoxycholic acid, NP-40, cat# 9016-45-9, purity >99.5, Ethylene glycol-bis(2-aminoethylether)-N,N,N′,N′-tetraacetic acid (EGTA), cat#03777 purity >99.5, 4-(2-Hydroxyethyl)piperazine-1-ethanesulfonic acid (HEPES), cat# H3375, purity >99.5, NDPH oxidase inhibitor diphenyleneneiodonium chloride
Antibiotics treatment leads to MDF
In order to study the effects of various antibiotics on mitochondrial functions we utilized human metastatic breast cancer cells (CAL51) and non-cancer primary human fibroblasts (NF) representing glycolytic-prone and OXPHOS-prone cellular models. We treated cells with penicillin/streptomycin (as a universal supplement to cell media), tetracycline, kanamycin, G418-geneticin (aminoglycoside antibiotics), puromycine (aminonucleoside antibiotic) blasticidine, (efficient selective antibiotic) with
Discussion
MDF has been recognized for many years as a characteristic feature of many chronic illnesses, partially classified as mitochondrial diseases [19]. Not withholding the importance of that fact, the current work was focused on the role of induced MDF in experimental models utilizing different antibiotics. In particular, our study confirmed that major mitochondrial functions can be significantly compromised upon exposure of the cells with antibiotics. This observation is especially important for
Author contributions
Study design (ME, DG, ML, AL); experiments for mitochondrial morphology (ME, AL); biochemical experiments (DG, ML, AL); Statistical analyses (ME, DG, AL); TEM experiments (AL, DG), drafting the manuscript (DG, ML, AL).
Acknowledgments
Authors are grateful to Dr. Krejci (Laboratory of DNA Recombination and Repair, National Centre for Biomolecular Research, Masaryk University, Brno) for sharing materials Dr. Stjepan Uldrijan's lab for giving initial access to SeaHorse apparatus. MELL. is a FIS investigator (Miguel Servet grant CP03/00101). AL received support from Marie Curie – COFUND program (INCOMED – GA 267128) for the Institut de Recerca Vall d’Hebrón, Barcelona, Spain.
References (19)
- et al.
2016: A ‘mitochondria’ odyssey
Trends Mol. Med.
(Apr–May 2016) Endosymbiosis and eukaryotic cell evolution
Curr. Biol. CB
(Oct. 2015)- et al.
FANCD2 depletion sensitizes cancer cells repopulation ability in vitro
Cancer Lett
(Oct. 2007) - et al.
Host cell autophagy activated by antibiotics is required for their effective antimycobacterial drug action
Cell Host Microbe
(May 2012) - et al.
Mitophagy is triggered by mild oxidative stress in a mitochondrial fission dependent manner
Biochim. Biophys. Acta
(Dec. 2012) - et al.
Autophagy and metastasis: another double-edged sword
Curr. Opin. Cell Biol.
(Apr. 2010) - et al.
Autophagy promotes focal adhesion disassembly and cell motility of metastatic tumor cells through the direct interaction of paxillin with LC3
Cell Rep.
(May 2016) Antibiotic use and its consequences for the normal microbiome
Science
(Apr. 2016)- et al.
Bactericidal antibiotics induce mitochondrial dysfunction and oxidative damage in mammalian cells
Sci. Transl. Med
(Jul. 2013)
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Both authors contributed equally to this work.