Systematic evaluation of the antitumor activity of three ruthenium polypyridyl complexes
Graphical abstract
DNA-binding behaviors and antitumor activity of the Ru(II) complexes were investigated. Complexes exerted its antitumor activity through increasing anti-migration and inducing cell cycle arrest at the S phase. In addition, mitochondrial membrane potential, reactive oxygen species, and colocalization tests were also evaluated by ImageXpress Micro XLS system.
Introduction
Malignant tumor remains one of the most challenging and dangerous health problems for human beings worldwide [[1], [2], [3], [4], [5], [6], [7], [8]]. According to the data from World Health Organization, in 2015, the number of deaths caused by cancer was 8.8 million, and nearly one-sixth of the deaths worldwide were attributed to malignant tumors [9]. Because of the huge therapeutic challenges of malignant tumors, great attention has been devoted to develop efficient protocols for the construction of new chemotherapeutic drugs recently [[10], [11], [12], [13], [14], [15], [16], [17]]. In order to discover more effective anti-tumor drugs, thousands of platinum-containing complexes have been synthesized, but only a few of these complexes have entered clinical trials [[18], [19], [20], [21]]. Moreover, this platinum-based complexes used in clinically has various adverse side effects, such as bone marrow suppression, allergies, tachycardia, renal toxicity, gastrointestinal reactions, etc., which greatly limits its use in the clinic [22,23]. To improve these shortcomings, alternative metal-based agents that lead to antitumor mechanisms different from platinum-based chemotherapeutics have been investigated and proved be a feasible methods. According to the literature, ruthenium metal complexes have attracted a great deal of interest from scientists due to their low cytotoxicity, rich photochemical and photobiological properties and anti-transfer properties [[24], [25], [26], [27], [28], [29], [30]]. In recent years, the application of ruthenium metal complexes in the field of anti-tumor has made significant research progress [[31], [32], [33], [34], [35], [36], [37]]. Two leading types of ruthenium complexes, NAMI-A and KP1019 have entered phase II clinical trials to treat malignant tumors [38]. In 2017, Liu found that [Ru(phen)2(MHPIP)](ClO4)2 (phen = 1,10-phenanthroline; MHPIP = 2-(1-methyl-1H-pyrazol-4-yl)-1H-imidazo[4,5-f][1,10]phenanthroline) induces HepG-2 cells apoptosis. In addition, the target Ru(II) complex can regulate the expression of caspase 3 and Bcl-2 family proteins [21]. Liu et al. reported that [(η6-p-cymene)Ru(N/O^N)Cl]0/+ (N/O^N = schiff base chelating ligands), a class of Half-sandwich Ru compounds with excellent anti-tumor activity, was able to effectively increase the level of reactive oxygen species (ROS) in HepG-2 cells and synergistically decrease the mitochondrial membrane potential (MMP) [39]. Recently, our group reported that ruthenium polypyridyl complexes containing heterocycle and alkynyl in their main ligands could enter the cytoplasm through the cell membrane and accumulate in the mitochondria [40].
Cinnamaldehyde, especially cinnamaldehyde derivatives, are a significant scaffold of various functional molecules [[41], [42], [43], [44]]. They not only serve as useful and important precursors for the synthesis of olefin, carboxylic acids and heterocycles, but also show a broad range of biological and pharmaceutical activities, such as antitumor, antifungal, antibacterial and anti-inflammatory [[45], [46], [47]]. Nonetheless, cinnamaldehyde-derived Ru(II) polypyridyl complexes are rarely studied as antitumor drugs. In continuation of our interest in the field of antitumor [[48], [49], [50]], herein, three Ru(II) polypyridyl complexes, [Ru(NN)2(CFPIP)](ClO4)2 (CFPIP = (E)-2-(4-fluorostyryl)-1H-imidazo[4,5-f][1,10]phenanthroline, N-N = 2′-bipyridine (bpy, Ru(II)-1), 1,10-phenanthroline (phen, Ru(II)-2) and 4,4′-dimethyl-2,2′-bipyridine (dmb, Ru(II)-3)) (Scheme 1), have been synthesized and characterized by IR, HRMS, 1H NMR, and 13C NMR. Complexes Ru(II)-1, Ru(II)-2, and Ru(II)-3 show excellent activity on the cell proliferation in HepG-2 cells with IC50 values of 21.4 ± 1.5, 18.0 ± 2.1, 22.3 ± 1.7 μM, respectively. Subsequently, the antitumor mechanism of the Ru(II) complexes was investigated by DNA binding behaviors, morphological changes, apoptosis, MMP (mitochondrial membrane potentials), ROS levels, cellular localization, cell cycle arrest and cell invasion. To sum up, our study demonstrates that target ruthenium complexes exhibited the excellent cytotoxicity against HepG-2 cells, and further induced apoptosis in HepG-2 cells through ROS-mediated mitochondrial dysfunction pathways.
Section snippets
Materials and methods
All reagents and solvents were purchased commercially and used without further purification unless otherwise noted. Calf thymus DNA (CT DNA) was obtained from the Sino American Biotechnology Company. Ltd. Ultrapure MilliQ water was used in all experiments. DMSO and RPMI 1640 were purchased from Sigma. Cell lines of HeLa (Human cervical cancer cell line), SGC-7901 (human gastric carcinoma cells), HepG-2 (Hepatocellular carcinoma cells), A549 (Human lung carcinoma cells), and normal LO2 cells
Synthesis and characterization
The ligands (E)-2-(4-fluorostyryl)-1H-imidazo[4,5-f][1,10]phenanthroline (CFPIP) and corresponding Ru(II) complexes were prepared using the literature method. The synthetic route of the ligands and complexes are elucidated in Scheme 1. Experiments have shown that the complexes are very stable (Fig. S3). Furthermore, the desired ruthenium polypyridyl complexes (Ru(II)-1, Ru(II)-2 and Ru(II)-3) were characterized by HRMS, IR, 1H NMR and 13C NMR. In the IR spectra, the peaks of 1639 cm−1 for
Conclusions
Three new ruthenium polypyridyl complexes containing CFPIP moiety were designed, synthesized and characterized, and theirs in vitro antitumor activity were investigated. The CFPIP moiety endows the Ru(II) complexes excellent physical and chemical properties, and Ru(II)-1, Ru(II)-2 and Ru(II)-3 exhibit higher antitumor activity than cisplatin against HepG-2 cells. The DNA binding experiments show that desired complexes interact with CT DNA through intercalative mode. Mechanism investigations
Declaration of Competing Interest
We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted. All authors have read and agreed to the submission.
Acknowledgements
The authors thank the Guangxi Natural Science Foundation (2018GXNSFBA050024, 2020GXNSFAA297227), Guangxi Science and Technology Base and Special Fund for Talents (AD19245008), Key Laboratory of Electrochemical and Magneto-chemical Function Materials (EMFM20211123) and the Ph. D. Scientific Research Foundation of Guilin University of Technology.
References (80)
- et al.
A monofunctional platinum(II)-based anticancer agent from a salicylanilide derivative: synthesis, antiproliferative activity, and transcription inhibition
J. Inorg. Biochem.
(2015) - et al.
Trans geometry in platinum antitumor complexes
Coord. Chem. Rev.
(2008) - et al.
Photoactivated platinum-based anticancer drugs
Coord. Chem. Rev.
(2018) - et al.
Studies of anticancer activity in vitro and in vivo of iridium(III) polypyridyl complexes-loaded liposomes as drug delivery system
Eur. J. Med. Chem.
(2019) - et al.
Evaluation of anticancer effect in vitro and in vivo of iridium(III) complexes on gastric carcinoma SGC-7901 cells
Eur. J. Med. Chem.
(2019) - et al.
High in vitro and in vivo antitumor activities of ln(III) complexes with mixed 5,7-dichloro-2-methyl-8-quinolinol and 4,4′-dimethyl-2,2′-bipyridyl chelating ligands
Eur. J. Med. Chem.
(2019) - et al.
Synthesis and anticancer properties of ruthenium (II) complexes as potent apoptosis inducers through mitochondrial disruption
Eur. J. Med. Chem.
(2017) - et al.
Platinum, palladium, gold and ruthenium complexes as anticancer agents: current clinical uses, cytotoxicity studies and future perspectives
Eur. J. Med. Chem.
(2017) - et al.
Combination of Ru(II) complexes and light: new frzontiers in cancer therapy
Chem. Sci.
(2015) - et al.
Cinnamaldehyde and its derivatives, a novel class of antifungal agents
Fitoterapia
(2016)
A review of cinnamaldehyde and its derivatives as antibacterial agents
Fitoterapia
Anti-oxidant and anti-inflammatory effects of cinnamaldehyde and eugenol on mononuclear cells of rheumatoid arthritis patients
Eur. J. Pharmacol.
Anticancer activity of two ruthenium(II) Polypyridyl complexes toward hepatocellular carcinoma HepG-2 cells
Polyhedron.
Design, synthesis and evaluation of anticancer activity of ruthenium (II) polypyridyl complexes
J. Inorg. Biochem.
The induction of apoptosis in HepG-2 cells by ruthenium(II) complexes through an intrinsic ROS-mediated mitochondrial dysfunction pathway
Eur. J. Med. Chem.
A ruthenium(II) complex containing a P-cresol group induces apoptosis in human cervical carcinoma cells through endoplasmic reticulum stress and reactive oxygen species production
J. Inorg. Biochem.
Investigation of inducing apoptosis in human lung cancer A549 cells and related mechanism of a ruthenium(II) polypyridyl complex
Inorg. Chem. Commun.
Mitochondrial ROS signaling in organismal homeostasis
Cell
Mitochondrial ROS regulation of proliferating cells
Free Radic. Biol. Med.
Ruthenium (II) polypyridyl complexes induce BEL-7402 cell apoptosis by ROS-mediated mitochondrial pathway
J. Inorg. Biochem.
Targeting and delivery of platinum-based anticancer drugs
Chem. Soc. Rev.
Nanoscale coordination polymers for platinum-based anticancer drug delivery
J. Am. Chem. Soc.
The interaction of platinum-based drugs with native biologically relevant proteins
Anal. Bioanal. Chem.
Target delivery of a novel antitumor organoplatinum(IV)-substituted polyoxometalate complex for safer and more effective colorectal cancer therapy in vivo
Adv. Mater.
Current status of platinum-based antitumor drugs
Chem. Rev.
Enantiomeric selectivity of ruthenium (II) chiral complexes with antitumor activity, in vitro and in vivo
J. Inorg. Biochem.
A copper(II) phenanthroline metallopeptide that targets and disrupts mitochondrial function in breast cancer stem cells
Angew. Chem. Int. Ed.
Cancer stem cell and bulk cancer cell active copper(II) complexes with vanillin Schiff Base derivatives and naproxen
Chem. Eur. J.
Identification and characterization of thiosemicarbazones with antifungal and antitumor effects: cellular Iron chelation mediating cytotoxic activity
Chem. Res. Toxicol.
Iron nanoparticles for low-power local magnetic hyperthermia in combination with immune checkpoint blockade for systemic antitumor therapy
Nano Lett.
Half-sandwich iridium(III) benzimidazole-appended imidazolium-based N-heterocyclic carbene complexes and antitumor application
Chem. Asian J.
A subset of new platinum antitumor agents kills cells by a multimodal mechanism of action also involving changes in the organization of the microtubule cytoskeleton
J. Med. Chem.
Design, synthesis and biological evaluation of a novel series of glycosylated platinum(iv) complexes as antitumor agents
Dalton Trans.
Novel antitumor platinum(II) conjugates containing the nonsteroidal anti-inflammatory agent diclofenac: synthesis and dual mechanisms of antiproliferative effects
Inorg. Chem.
Modulating the anticancer activity of ruthenium(II)-Arene complexes
J. Med. Chem.
The side effects of platinum-based chemotherapy drugs: a review for chemists
Dalton Trans.,
New ruthenium(II)-letrozole complexes as anticancer therapeutics
J. Med. Chem.
Interaction of ruthenium (II) antitumor complexes with d (ATATAT) 2 and d (GCGCGC) 2: a theoretical study
New J. Chem.
Interaction of anticancer ruthenium compounds with proteins: high-resolution X-ray structures and raman microscopy studies of the adduct between hen egg white lysozyme and AziRu
Inorg. Chem.
Characterization of the binding sites of the anticancer ruthenium(III) complexes KP1019 and KP1339 on human serum albumin via competition studies
J. Biol. Inorg. Chem.
Cited by (11)
Antitumor studies evaluation of triphenylphosphine ruthenium complexes with 5,7-dihalo-substituted-8-quinolinoline targeting mitophagy pathways
2023, Journal of Inorganic BiochemistrySynthesis and characterization of polypyridine ruthenium(II) complexes and anticancer efficacy studies in vivo and in vitro
2022, Journal of Inorganic BiochemistryCitation Excerpt :Taken together, we think it is urgent how to reduce adverse reactions and find new chemotherapy drugs that are more effective and have fewer toxic side effects. In the process of searching for new chemotherapeutic drugs, transition metal-based compounds have become the particularly potential chemotherapeutic candidates (including ruthenium, iridium, rhenium, copper, rhodium, and osmium) [14–18]. They would be the next generation of anticancer metallotherapy and serve as potent and effective chemotherapeutic agents.
The cyclometalated iridium (III) complex based on 9-Anthracenecarboxylic acid as a lysosomal-targeted anticancer agent
2022, Journal of Inorganic BiochemistryCitation Excerpt :It has been identified that p38, a member of the MAPK family, was a mediator of lysosomal damage response in a ROS-dependent manner and a potential target to enhance the cytotoxic effects of lysosomal damage [50]. Futhermore, the generation of ROS is often involved in the mechanism of the cytotoxic effects of the metal-based agents [51,52]. To determine whether Ir-9-Ac could induce ROS production, the cellular redox state was analyzed by DHE, which exhibited blue fluorescence in reduced form and could be converted to the red fluorescenece emiting 2-hydroxyethidium in the presence of cellular superoxide.
Enhanced in vitro cytotoxicity and antitumor activity in vivo of iridium(III) complexes liposomes targeting endoplasmic reticulum and mitochondria
2022, Journal of Inorganic BiochemistryCitation Excerpt :Cisplatin, as an effective anticancer drug, has serious side effects, severe toxicity and drug resistance [5,6], which prompts people to continuously search different metal anticancer drug as alternatives of cisplatin. In recent years, the studies on metal complexes as anticancer drugs have been made great progress [7–14]. In particular, the anticancer activity of iridium(III) complexes has attracted a great interest, many iridium(III) complexes show unique anticancer efficacy [15–24].
Redox Reactions of Coordination Compounds in the Biomedical Environment
2023, Fundamental and Biomedical Aspects of Redox Processes