Metal complexes in cancer therapy - an update from drug design perspective

Disulfiram-gold-nanorod integrate for effective tumor targeting and photothermal-chemical synergistic therapy

Herein, we successfully constructed a combination therapeutic nanoplatform with high tumor targeting for cancer treatment by integrating gold nanorods with disulfiram (denoted Au-DSF). The Au-DSF integrates possess a uniform length (70 nm), excellent photothermal conversion ability and a high DSF loading content (23.2%), and the loaded DSFs show glutathione-, acid-, and laser-responsive release properties. The Au-DSF integrates show significantly enhanced cellular uptake efficiency in breast cancer cells due to the ability of DSF to chelate to the intracellular copper (Cu) which is present at high concentrations. Furthermore, the Au-DSF exhibits improved circulation time (mean residence time = 28.4 h) and increased tumor accumulation (12.0%), due to the targeting of DSF to the abundant Cu ions at the tumor site. Moreover, the DSF/Cu complexes potently elevate reactive oxygen species, which effectively induce cancer cell apoptosis. In vivo experiments show that the Au-DSF integrates dramatically decrease tumor size via photothermal therapy and chemotherapy. Hematoxylin-eosin and TUNEL staining show that the Au-DSF integrates induce necrosis and apoptosis in cancer cells. The high therapeutic efficiency of the Au-DSF integrates for breast cancer is further demonstrated by the reduced elasticity seen in ultrasound elastography, and the absence of perfusion of the contrast agent in contrast-enhanced ultrasound imaging in tumors.

β-Carboline copper complex as a potential mitochondrial-targeted anticancer chemotherapeutic agent: Favorable attenuation of human breast cancer MCF7 cells via apoptosis

The development of preferentially selective cancer chemotherapeutics is a new trend in drug research. Thus, we designed and synthesized novel ternary complexes, [Cu(tryp)(Hnor)₂(DMSO)]NO₃ (1) and [Zn(tryp)(Hnor)₂(DMSO)]NO₃(2) (tryp = DL-Tryptophane; Hnor = Norharmane, β-carboline; DMSO = Dimethyl sulfoxide), characterized with elemental analysis, FTIR, UV–vis, FL, NMR, ESI-MS, and molar conductivity. Furthermore, the TD-DFT studies with UV–vis and FTIR validated the proposed structures of 1 and 2. Moreover, we evaluated the HOMO-LUMO energy gap and found that 1 has a smaller energy gap than 2. Then, 1 and 2 were assessed for anticancer chemotherapeutic potential against cancer cell lines MCF7 (human breast cancer) and HepG2 (human liver hepatocellular carcinoma) as well as the non-tumorigenic HEK293 (human embryonic kidney) cells. The MTT assay illustrated the preferentially cytotoxic behavior of 1 when compared with that of 2 and cisplatin (standard drug) against MCF7 cells. Moreover, 1 was exposed to MCF7 cells, and the results indicated the arrest of the G2/M phases, which followed the apoptotic pathway predominantly. Generation of ROS, GSH depletion, and elevation in LPO validated the redox changes prompted by 1. These studies establish the great potential of 1 as a candidate for anticancer therapeutics.

Ruthenium(II) Complex Containing a Redox-Active Semiquinonate Ligand as a Potential Chemotherapeutic Agent: From Synthesis to In Vivo Studies

Chemotherapy remains one of the dominant treatments to cure cancer. However, due to the many inherent drawbacks, there is a search for new chemotherapeutic drugs. Many classes of compounds have been investigated over the years to discover new targets and synergistic mechanisms of action including multicellular targets. In this work, we designed a new chemotherapeutic drug candidate against cancer, namely, [Ru(DIP)₂(sq)](PF₆) (Ru-sq) (DIP = 4,7-diphenyl-1,10-phenanthroline; sq = semiquinonate ligand). The aim was to combine the great potential expressed by Ru(II) polypyridyl complexes and the singular redox and biological properties associated with the catecholate moiety. Experimental evidence (e.g., X-ray crystallography, electron paramagnetic resonance, electrochemistry) demonstrates that the semiquinonate is the preferred oxidation state of the dioxo ligand in this complex. The biological activity of Ru-sq was then scrutinized in vitro and in vivo, and the results highlight the promising potential of this complex as a chemotherapeutic agent against cancer.

Potent Anticancer Efficacy of First-In-Class CuII and AuIII Metaled Phosphorus Dendrons with Distinct Cell Death Pathways

First-in-class Cu^II and Au^III metaled phosphorus dendrons were synthesized and showed significant antiproliferative activity against several aggressive breast cancer cell lines. The data suggest that the cytotoxicity increases with reducing length of the alkyl chains, whereas the replacement of Cu^II with Au^III considerably increases the antiproliferative activity of metaled phosphorus dendrons. Very interestingly, we found that the cell death pathway is related to the nature of the metal complexed by the plain dendrons. Cu^II metaled dendrons showed a potent caspase-independent cell death pathway, whereas Au^III metaled dendrons displayed a caspase-dependent apoptotic pathway. The complexation of plain dendrons with Au^III increased the cellular lethality versus dendrons with Cu^II and promoted the translocation of Bax into the mitochondria and the release of Cytochrome C (Cyto C).

Inorganic reaction mechanisms. A personal journey

This review covers highlights of the work performed in the van Eldik group on inorganic reaction mechanisms over the past two decades in the form of a personal journey. Topics that are covered include, from NO to HNO chemistry, peroxide activation in model porphyrin and enzymatic systems, the wonder-world of Ru^III(edta) chemistry, redox chemistry of Ru(iii) complexes, Ru(ii) polypyridyl complexes and their application, relevant physicochemical properties and reaction mechanisms in ionic liquids, and mechanistic insight from computational chemistry. In each of these sections, typical examples of mechanistic studies are presented in reference to related work reported in the literature.

The Zn(S-pr-thiosal)2 complex attenuates murine breast cancer growth by inducing apoptosis and G1/S cell cycle arrest

Aim: We investigated the antitumor effects of zinc(II) complex with S-propyl thiosalicylic acid [Zn(S-pr-thiosal)₂] in 4T1 murine breast cancer model. Results: The Zn(S-pr-thiosal)₂ complex reduced primary tumor growth in vivo and induced tumor cell apoptosis. The Zn(S-pr-thiosal)₂ complex disrupted the balance between pro- and antiapoptotic Bcl-2 family members in 4T1 cells and induced G1/S cell cycle arrest. The Zn(S-pr-thiosal)₂ complex increased the percentage of p16, p21 and p27 positive 4T1 cells. There was a significantly decrease in expression of STAT3 and its targets c-Myc and cyclin D3 in 4T1 cells treated with the Zn(S-pr-thiosal)₂ complex thus contributing to G1/S cell cycle arrest and/or apoptosis. Conclusion: Our data suggest that the Zn(S-pr-thiosal)₂ complex restricted tumor growth through induction of mitochondrial-driven apoptosis and suppression of cell cycle progression.

Binding Kinetics of Ruthenium Pyrithione Chemotherapeutic Candidates to Human Serum Proteins Studied by HPLC-ICP-MS

The development of ruthenium-based complexes for cancer treatment requires a variety of pharmacological studies, one of them being a drug's binding kinetics to serum proteins. In this work, speciation analysis was used to study kinetics of ruthenium-based drug candidates with human serum proteins. Two ruthenium (Ru) complexes, namely [(η⁶-p-cymene)Ru(1-hydroxypyridine-2(1H)-thionato)Cl] (1) and [(η⁶-p-cymene)Ru(1-hydroxypyridine-2(1H)-thionato)pta]PF₆ (2) (where pta = 1,3,5-triaza-7-phosphaadamantane), were selected. Before a kinetics study, their stability in relevant media was confirmed by nuclear magnetic resonance (NMR). Conjoint liquid chromatography (CLC) monolithic column, assembling convective interaction media (CIM) protein G and diethylamino (DEAE) disks, was used for separation of unbound Ru species from those bound to human serum transferrin (Tf), albumin (HSA) and immunoglobulins G (IgG). Eluted proteins were monitored by UV spectrometry (278 nm), while Ru species were quantified by post-column isotope dilution inductively coupled plasma mass spectrometry (ID-ICP-MS). Binding kinetics of chlorido (1) and pta complex (2) to serum proteins was followed from 5 min up to 48 h after incubation with human serum. Both Ru complexes interacted mainly with HSA. Complex (1) exhibited faster and more extensive interaction with HSA than complex (2). The equilibrium concentration for complex (1) was obtained 6 h after incubation, when about 70% of compound was bound to HSA, 5% was associated with IgG, whereas 25% remained unbound. In contrast, the rate of interaction of complex (2) with HSA was much slower and less extensive and the equilibrium concentration was obtained 24 h after incubation, when about 50% of complex (2) was bound to HSA and 50% remained unbound.

Rapid Microwave-Assisted Cisplatin-Loaded Solid Lipid Nanoparticles: Synthesis, Characterization and Anticancer Study

Cisplatin is one of the most leading potent chemotherapy drugs prescribed for the treatment of most solid tumors. However, the induction of toxicities and the development of resistance restricts its applications. Efforts are made in the proposed study to control the delivery of cisplatin to tumor sites by incorporating it into solid lipid nanoparticle (SLNs) drug carriers. By considering this fact, in the current research work, a single-step, one-pot, microwave-assisted technology was used to produce cisplatin-loaded SLNs. The shape of the SLNs was observed to be spherical, with a uniform size distribution of 74.85 nm, polydispersity index (PDI) of 0.311, and zeta potential of -20.8 mV. The percentage of encapsulation efficiency was found to be 71.85%. In vitro drug release study was calculated to be 80% in 24 h. The formulation in blood was found to be safe; a study of hemolysis confirmed this. Breast cancer cell line MCF-7 was used to test cytotoxicity and cellular interaction of cisplatin-loaded SLNs with an IC₅₀ value of 6.51 ± 0.39 μg/mL. Overall, the results of our findings show that the approach of SLNs-based, cisplatin-based, drug delivery has led to increased sustainability in breast cancer therapy with superior biocompatibility.

Anionic versus neutral Pt(II) complexes: The relevance of the charge for human serum albumin binding

The focus of this work is pointing out the different behavior of two structurally related Pt^(II) complexes, the anionic cyclometalated NBu₄[(Bzq)Pt(Thio)], 1 and the neutral [(Phen)Pt(Thio)], 2, (Bzq = benzo[h]quinoline, Phen = 1,10-phenantroline, Thio = 1,2-benzenedithiolate), on the interaction with human serum albumin (HSA), a key drug-delivery protein in the bloodstream. Being very limited the number of anionic Pt^(II) complexes reported to date, this is a pioneering example of report on a protein-ligand interaction involving a negatively charged platinum compound. The study was carried out by using fluorescence spectroscopy, differential scanning calorimetry and molecular docking simulations. The results revealed a strong binding affinity between the anionic compound and the protein, whereas a weak/moderate binding interaction was highlighted for the neutral one. Comparative studies with site specific ligands (warfarin and ibuprofen), allowed us to identify the protein binding sites of the two compounds. The work aims to shed light on the relevance of the charge in designing new drugs with a favorable binding affinity for HSA, which strongly contributes to influence their pharmacological and toxicological profile.

Synthesis, Characterization and DNA Binding Investigations of a New Binuclear Ag(I) Complex and Evaluation of Its Anticancer Property

Aim

A new Ag(I) complex (A₃) was synthesized and evaluated for its anticancer activity against human cancer cell lines.

Materials and Methods

The complex A₃ was characterized by ¹H, ¹³C, and ³¹P nuclear magnetic resonance (NMR), infrared (IR) spectra, elemental analysis, and X-ray crystallography. The interaction of the complex with CT-DNA was studied by electronic absorption spectra, fluorescence spectroscopy, and cyclic voltammetry; cell viability (%) was assessed by absorbance measurement of the samples.

Results

The interaction mode of the complex A₃ with DNA is electrostatic, and this complex shows good potential in anticancer properties against HCT 116 (human colorectal cancer cells) and MDA-MB-231 (MD Anderson-metastatic breast) cell lines with 0.5 micromolar concentrations.

Conclusion

The Ag(I) complex could interact with DNA noncovalently and has anticancer properties.

Synthesis, Structural, and Cytotoxic Properties of New Water-Soluble Copper(II) Complexes based on 2,9-Dimethyl-1,10-Phenanthroline and Their One Derivative Containing 1,3,5-Triaza-7-Phosphaadamantane-7-Oxide

A series of water-soluble copper(II) complexes based on 2,9-dimethyl-1,10-phenanthroline (dmphen) and mixed-ligands, containing PTA=O (1,3,5-triaza-7-phosphaadamantane-7-oxide) have been synthesized and fully characterized. Two types of complexes have been obtained, monocationic [Cu(NO₃)(O-PTA=O)(dmphen)][PF₆] (1), [Cu(Cl)(dmphen)₂][PF₆] (2), and neutral [Cu(NO₃)₂(dmphen)] (3). The solid-state structures of all complexes have been determined by single-crystal X-ray diffraction. Magnetic studies for the complex 1–3 indicated a very weak antiferromagnetic interaction between copper(II) ions in crystal lattice. Complexes were successfully evaluated for their cytotoxic activities on the normal human dermal fibroblast (NHDF) cell line and the antitumor activity using the human lung carcinoma (A549), epithelioid cervix carcinoma (HeLa), colon (LoVo), and breast adenocarcinoma (MCF-7) cell lines. Complexes 1 and 3 revealed lower toxicity to NHDF than A549 and HeLa cells, meanwhile compound 2 appeared to be more toxic to NHDF cell line in comparison to all cancer lines. Additionally, interactions between the complexes and human apo-transferrin (apo-Tf) using fluorescence and circular dichroism (CD) spectroscopy were also investigated. All compounds interacted with apo-transferrin, causing same changes of the protein conformation. Electrostatic interactions dominate in the 1/2 – apo- Tf systems and hydrophobic and ionic interactions in the case of 3.

Heavy Metal Toxicity in Armed Conflicts Potentiates AMR in A. baumannii by Selecting for Antibiotic and Heavy Metal Co-resistance Mechanisms

Acinetobacter baumannii has become increasingly resistant to leading antimicrobial agents since the 1970s. Increased resistance appears linked to armed conflicts, notably since widespread media stories amplified clinical reports in the wake of the American invasion of Iraq in 2003. Antimicrobial resistance is usually assumed to arise through selection pressure exerted by antimicrobial treatment, particularly where treatment is inadequate, as in the case of low dosing, substandard antimicrobial agents, or shortened treatment course. Recently attention has focused on an emerging pathogen, multi-drug resistant A. baumannii (MDRAb). MDRAb gained media attention after being identified in American soldiers returning from Iraq and treated in US military facilities, where it was termed "Iraqibacter." However, MDRAb is strongly associated in the literature with war injuries that are heavily contaminated by both environmental debris and shrapnel from weapons. Both may harbor substantial amounts of toxic heavy metals. Interestingly, heavy metals are known to also select for antimicrobial resistance. In this review we highlight the potential causes of antimicrobial resistance by heavy metals, with a focus on its emergence in A. baumanni in war zones.

Dual function of lectins — new perspectives in targeted photodynamic therapy

Porphyrins and phthalocyanines are photosensitizers (PS) that are used in clinical imaging, detection of cancer cells and are particularly applied in photodynamic therapy (PDT). Many scientists have been focused on the design of different porphyrin compounds. However, similar to other anti-cancer agents, they cannot selectively recognize tumor tissues. Scientists are seeking new methods to overcome this problem and to find appropriate targeted delivery strategies. Plant lectins are especially suitable molecules for such targeting as they preferentially recognize specific antigens on the glycosylated cancer cells. This review will give more detailed information about the dual function of lectins and their interactions with PSs, which is a new perspective in targeted PDT. The implications and potential applications of such studies will also be discussed.

Therapeutic potential of dithiocarbamate supported gold compounds

Chrysotherapy or aurotherapy, the use of gold as medicine, is two thousand years old. Hitherto, numerous diverse gold stabilizing ligands for instance vitamins, pyridine, phosphines, naphthylamine and xanthanes have been developed and their 'chelating effect' in addition to their anti-proliferative properties have been extensively studied. Recent advances in the field of bioinorganic chemistry have led to the design of biologically relevant metal complexes with appropriate fine-tuned ligands such as metallic conjugates of dithiocarbamates (DTCs). DTC compounds have been recognised to possess diverse applications and have demonstrated interesting biological properties. For instance, the chemoprotective and antitumour properties of gold metal ions and DTC compounds respectively, presents an innovative and effective approach to cancer management. This review presents therefore the therapeutic potential of DTC ligand systems as a support for gold compounds. The importance of dithiocarbamate supported gold compounds as potential therapeutic agents is highlighted with emphasis on the therapeutic potential of gold(iii) and gold(i) dithiocarbamate derivatives.

Restoration and Enhancement of Immunogenic Cell Death of Cisplatin by Coadministration with Digoxin and Conjugation to HPMA Copolymer

Complete tumor eradication is the ultimate goal of cancer therapy. However, the majority of anticancer drugs cause nonimmunogenic cell death and only exert on-site anticancer activities. The intrinsic genomic instability of cancer allows for the persistence and later expansion of treatment-resistant clones after surviving a sort of Darwinian selection of chemotherapy. Additional incorporation of immunotherapy, which is robust and individualized could be game-changing. Herein, we report a combination strategy that delivers nonimmunogenic cell death inducer Cisplatin to treat primary tumors and converts the tumor cells into vaccines that spurs a long-lasting immune response against residual tumors to prevent tumor recurrence and metastasis. Cisplatin(IV) prodrug was linked to the N-(2-hydroxypropyl) methacrylamide (HPMA) copolymer (P-Cis) and coadministered with digoxin (Dig), which eventually launched two attacks to cancer cells. First, P-Cis exhibited superior tumor retention and cytotoxicity over free Cisplatin (to inhibit the primary tumor growth). Then, Dig reversed the inability of Cisplatin to trigger calreticulin exposure, and HPMA copolymer-amplified Cisplatin-induced ATP release. These complementary mechanisms induced potent immunogenic cell death that promotes dendritic cell maturation and activates CD8⁺ T cell responses. In established tumor models, P-Cis + Dig combination completely eradicate tumors with no residual cancer cells remaining. Cancer cells succumbing to P-Cis + Dig could protect syngeneic mice against the subsequent challenge with living cells of the same type and stimulated robust abscopal and antimetastatic effects. Such a strategy might be promising to restore the immunogenicity of nonimmunogenic drugs and generate vaccine-like functions for improved immunochemotherapy.

Oxalato bridged coordination polymer of manganese(iii) involving unconventional O⋯π-hole(nitrile) and antiparallel nitrile⋯nitrile contacts: antiproliferative evaluation and theoretical studies

Unconventional O⋯π-hole(nitrile) and antiparallel nitrile⋯nitrile contacts have been theoretically investigated for a Mn(iii) coordination polymer considering cytotoxicity, apoptosis, ROS generation, molecular docking and pharmacophore features.

Design, synthesis, characterization and evaluation of the anticancer activity of water-soluble half-sandwich ruthenium(ii) arene halido complexes

Synthesis, crystal structure determination, DFT studies, experimental and theoretical evaluation of DNA/BSA interactions and cytotoxicity studies of three piano-stool Ru(ii)(p-cymene)chloride complexes (1–3) are presented herein.

Luminescent Zn(ii) and Cd(ii) complexes with chiral 2,2′-bipyridine ligands bearing natural monoterpene groups: synthesis, speciation in solution and photophysics

Coordination of chiral ligands containing a 2,2′-bipyridine moiety and natural terpene (+)-limonene or (+)-3-carene groups to zinc(ii) and cadmium(ii) leads to excitation wavelength dependent emission.

Antitumour and Antimetastatic Effects and Safety Profile of a New Magnesium(II)-Chrysin Complex

Chrysin is a flavone found in many plant extracts including blue passion flower, propolis and honey. The magnesium(ii) cation is an essential metal for life and it is involved in a variety of metabolic and physiological functions. Biological activities of flavonoids can be improved by complexation with metals. For this reason, Mgchrys was synthesised. The complex was characterised by spectroscopic techniques (ultraviolet–visible absorption spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR), 1H and 13C-NMR) and elemental and thermogravimetric analysis. The results indicated that chrysin reacts with magnesium(ii) through a 4-carbonyl-5-hydroxy chelation site. The computational study suggests the coexistence of at least twelve conformers of Mgchrys at room temperature. There are six most stable conformers that show square-pyramidal and distorted square-pyramidal geometries. In addition, anticancer and antimetastatic activities of Mgchrys on the A549 cell line were evaluated and compared with the metal and the free ligand. The complex did not show cytotoxicity against normal lung fibroblasts but it behaved as a cytotoxic drug against the cancer cell line with oxidative stress being its probable mechanism of action. However, Mgchrys inhibited the different steps involved in the metastatic cascade: adhesion to fibronectin, migration and invasion. The compounds displayed no acute toxicity (Artemia salina test) and no mutagenic effect (Ames test).

Hypoxia efficient and glutathione-resistant cytoselective ruthenium(ii)-p-cymene-arylimidazophenanthroline complexes: biomolecular interaction and live cell imaging

A series of ruthenium(ii)–arene-2-arylimidazophenanthroline based DNA targeting, cytoselective, hypoxia efficient and glutathione-resistant luminescent anticancer drugs have been developed which are also represented as HeLa cell imaging probes.

Synthesis, X-ray structure, antiproliferative activity, interaction with HSA and docking studies of three novel mono and binuclear copper complexes containing the maltol ligand

The present study aims at synthesizing three new copper(ii) complexes of maltol in the presence of 1,10-phenanthroline-, 2,2′-bipyridine- and 4,4-dibromo-2,2′-bipyridine ligands.

Designing of novel zinc(ii) Schiff base complexes having acyl hydrazone linkage: study of phosphatase and anti-cancer activities

The phosphatase and anti-cancer activities of three novel acyl hydrazone based zinc(ii) Schiff base complexes have been unveiled.

Copper(ii) complexes containing enoxacin and heterocyclic ligands: synthesis, crystal structures and their biological perspectives

Two copper-based complexes with a distorted square pyramidal geometry show excellent binding and cleavage affinity towards DNA and proteins. Also, these complexes have potential cytotoxicity against MCF-7 cancer cells.

Synthesis of new N,N′-Pd(Pt) complexes based on sulfanyl pyrazoles, and investigation of their in vitro anticancer activity

The synthesis of new N,N′-mononuclear bi-ligand Pd(ii) and tri-ligand Pt(ii)complexes bearing sulfanyl(phenyl, benzyl, cyclohexyl, 4-hydroxyphenyl)3,5-dimethyl-1H-pyrazole ligands has been carried out. The obtained compounds were studied for apoptosis-inducing activity and effect on the cell cycle for Jurkat, K562, and U937 neoplastic cell cultures and conditionally normal human embryonic kidney HEK293 cells. The cells showed the highest sensitivity to platinum and palladium complexes in comparison with ligands and cisplatin. The cytotoxic properties are enhanced for compounds with cyclohexyl substituents at the S-atom in sulfanyl pyrazoles and complexes.

Efficient cytostatics against Jurkat, K562 and U937 neoplastic cell lines were found among the synthesized new Pd(ii) and Pt(ii)complexes (six examples) with sulfanyl-1H-pyrazole ligands using in vitro assay.

Iron and copper complexes with antioxidant activity as inhibitors of the metastatic potential of glioma cells

Iron and copper complexes with antioxidant activity able to inhibit tumor metastasis by inhibiting epithelial-mesenchymal transition in glioma cells.

Anticancer potency of novel organometallic Ir(iii) complexes with phosphine derivatives of fluoroquinolones encapsulated in polymeric micelles

A 3D model of cell culturing (spheroids) was explored and the anticancer potential of the selected novel organometallic Ir(iii) complex encapsulated in Pluronic p-123 micelles was clearly proved.

Palladium(ii) complexes bearing 1-iminothiolate-3,5-dimethylpyrazoles: synthesis, cytotoxicity, DNA binding and enzymatic inhibition studies

This work describes the enzymatic inhibitory activity of four novel Pd(ii) complexes towards topoisomerase IIα and cathepsins B and L.In silicostudies agree well with the enhancedin vitrocathepsin B inhibition induced by compound4(58% at 10 μM).

Three-dimensional cell culture models for metallodrug testing: induction of apoptosis and phenotypic reversion of breast cancer cells by the trans-[Ru(PPh3)2(N,N-dimethyl-N-thiophenylthioureato-k2O,S)(bipy)]PF6 complex

Effects of trans-[Ru(PPh₃)2(N,N-dimethyl-N-thiophenylthioureato-k₂O,S)(bipy)]PF₆ complex on cytotoxicity, on the induction of apoptosis and on the phenotypic reversion of tumor cells in different 3D culture techniques.

Potent and selective PTP1B inhibition by a platinum(ii) complex: possible implications for a new antitumor strategy

Showing anti-proliferation activity against MCF7 cells better than cisplatin, a platinum(ii) complex, [PtL(DMSO)Cl], was found to potently and selectively inhibit protein tyrosine phosphatase 1B (PTP1B), a putative target for anticancer agents, suggesting a new possible anticancer strategy based on platinum drugs.

Anticancer and antimetastatic activity of copper(II)-tropolone complex against human breast cancer cells, breast multicellular spheroids and mammospheres

The goal of this work was to display the anticancer and antimetastatic activity of a copper(II) with tropolone (trp), complex [Cu(trp)₂] toward human breast cancer cells in monolayer (2D) and spheroids (3D). Cytotoxicity assays against MCF7 (IC_50(complex) = 5.2 ± 1.8 μM, IC_50(CDDP) = 19.3 ± 2.1 μM) and MDA-MB-231 (IC_50(complex) = 4.0 ± 0.2 μM, IC_50(CDDP) = 27.0 ± 1.9 μM) demonstrate that [Cu(trp)₂] exert greater antitumor potency than cisplatin (CDDP) on 2D and 3D human breast cancer cell models. Besides, [Cu(trp)₂] inhibits cell migration by reducing the metalloproteinases activities and the compound undergoes the breast cancer cells to apoptosis at lower concentrations (2.5-10 μM). Moreover, [Cu(trp)₂] overcame CDDP presenting an IC₅₀ value 26-fold more lower against breast multicellular spheroids ((IC_50(complex) = 4.9 μM, IC_50(CDDP) = 130 μM)). Also, our results showed that [Cu(trp)₂] inhibited the cell migration and cell invasion of breast multicellular spheroids, showing that [Cu(trp)₂] exhibited antimetastatic properties. On the other hand, [Cu(trp)₂] reduced mammosphere forming capacity affecting the size and number of mammospheres. Taken together, [Cu(trp)₂] exhibited anticancer and antimetastatic properties on monolayer (2D) and spheroids (3D) derived from human breast cancer cells.

Platinum Derivatives Effects on Anticancer Immune Response

Along with surgery and radiotherapy, chemotherapeutic agents belong to the therapeutic arsenal in cancer treatment. In addition to their direct cytotoxic effects, these agents also impact the host immune system, which might enhance or counteract their antitumor activity. The platinum derivative compounds family, mainly composed of carboplatin, cisplatin and oxaliplatin, belongs to the chemotherapeutical arsenal used in numerous cancer types. Here, we will focus on the effects of these molecules on antitumor immune response. These compounds can induce or not immunogenic cell death (ICD), and some strategies have been found to induce or further enhance it. They also regulate immune cells' fate. Platinum derivatives can lead to their activation. Additionally, they can also dampen immune cells by selective killing or inhibiting their activity, particularly by modulating immune checkpoints' expression.

In vitro apoptotic effect of Zinc(II) complex with N-donor heterocyclic ligand on breast cancer cells

Background

The synthesis of new ligand and transition metal complexes have drawn great attention in cancer treatment due to excellent DNA cleavage activities and high antitumor activity.

Objective

The purpose of this study was to synthesize a new Zn(II) complex with 2,2′-bipyridine (bpy) ligand, [Zn(bpy)2(H2O)]2(ClO4), and to investigate the potential therapeutic activity against breast cancer.

Materials and methods

Zn(II) complex was obtained and structurally characterized using crystallography and other spectroscopic methods. The cytotoxic and apoptotic effects of Zn(II) complex on MCF7 breast cancer and HUVEC control cells were evaluated by WST-1, Annexin V and cell cycle analysis.

Results

The spectroscopic data demonstrated that Zn(II) complex was successfully synthesized. Furthermore, Zn(II) complex exhibited significant cytotoxic effect on MCF7 breast cancer and HUVEC cells (p < 0.01). MCF7 and HUVEC cells proliferation was reduced to 11.0% and 52.6%, respectively at 10 μM for 48 h. Additionally, Zn(II) complex significantly induced apoptotic cell death (84.87%) and caused S phase arrest (36.4%) in MCF7 cells at 10 μM (p < 0.01).

Conclusions

Zn(II) complex has great therapeutic potential for the treatment of breast cancer. However, further studies are warranted to identify the underlying mechanisms of apoptotic cell death and to reduce the toxicity of Zn(II) complex on control cells.

Non-Steroidal Androgen Receptor Antagonists and Prostate Cancer: A Survey on Chemical Structures Binding this Fast-Mutating Target

The Androgen Receptor (AR) pathway plays a major role in both the pathogenesis and progression of prostate cancer. In particular, AR is chiefly involved in the development of Castration-Resistant Prostate Cancer (CRPC) as well as in the resistance to the secondgeneration AR antagonist enzalutamide, and to the selective inhibitor of cytochrome P450 17A1 (CYP17A1) abiraterone. Several small molecules acting as AR antagonists have been designed and developed so far, also as a result of the ability of cells expressing this molecular target to rapidly develop resistance and turn pure receptor antagonists into ineffective or event detrimental molecules. This review covers a survey of most promising classes of non-steroidal androgen receptor antagonists, also providing insights into their mechanism of action and efficacy in treating prostate cancer.

Potential of Tribological Properties of Metal Nanomaterials in Biomedical Applications

Metallic nanomaterials show tremendous applications in biomedical devices due to compatible integration into the most of the biological systems as they are nano- structured. Metallic nanomaterials are capable of mimicking all the three major antioxidant enzymes such as catalase (CAT), peroxidase and oxidase, to control the level of reactive oxygen species (ROS) inside the cell as an alternative strategy over conventional one which has biological toxicity and have several adverse effects, if accumulation takes places during the treatment. This anti-oxidant property of metallic nanomaterials demonstrates as a promising candidate for its biomedical application in disease conditions where the excessive level of ROS causes damage to DNA, lipids and protein in several conditions such as diabetes, cancer and neurodegenerative diseases. Tribology is the study of interacting surfaces in motion and the measurement of properties such as friction, wear-tear and abrasion. While designing nano-scale biomedical devices, the consideration of tribology is particularly important because the high surface area ratio enhances problems with friction and wear-tear which can further affects its function as well as longevity.