Doble synergetic anticancer activity through a combined chemo-photodynamic therapy and bioimaging of a novel Cas-ZnONPs all-in-one system.

A strategy for cancer treatment was implemented, based on chemo-photodynamic therapy, utilizing a novel formulation, low-cost system called Cas-ZnONPs. This system consisted of the incorporation of Casiopeina III-ia (CasIII-ia), a hydrophilic copper coordination compound with well-documented anti-neoplastic activity, on Zinc oxide nanoparticles (ZnONPs) with apoptotic activity and lipophilicity, allowing them to permeate biological barriers. Additionally, ZnONPs exhibited fluorescence, with emission at different wavelengths depending on their agglomeration and enabling real-time tracking biodistribution. Also, ZnONPs served as a sensitizer, generating reactive oxygen species (ROS) in situ. In in vitro studies on HeLa and MDA-MB-231 cell lines, a synergistic effect was observed with the impregnated CasIII-ia on ZnONPs. The anticancer activity had an increase in cellular inhibition, depending on the dose of exposure to UV-vis irradiation. In in vivo studies utilized zebrafish models for xenotransplanting stained MDA-MB-231 cells and testing the effectiveness of Cas-ZnONPs treatment. The treatment successfully eliminated cancer cells, both when combined with Photodynamic Therapy (PDT) and when used alone. However, a significantly higher concentration (50 times) of Cas-ZnONPs was required in the absence of PDT. This demonstrates the potential of Cas-ZnONPs in cancer treatment, especially when combined with PDT.

Casiopeina III-ia: a copper compound with potential use for treatment of infections caused by Leishmania mexicana.

Introduction Casiopeina III-ia (CasIII-ia) is a mixed chelate copper (II) compound capable of interacting with free radicals generated in the respiratory chain through redox reactions, producing toxic reactive oxygen species (ROS) that compromise the viability of cancer cells, bacteria and protozoa. Due to its remarkable effect on protozoa, this study evaluated the effect of CasIII-ia on Leishmania mexicana (L. mexicana) amastigotes and its potential use as a treatment for cutaneous leishmaniasis in the murine model. Methods We analyzed the leishmanicidal effect of CasIII-ia on L. mexicana amastigotes, and on their survival in bone marrow-derived macrophages. Furthermore, we evaluated the production of ROS in treated parasites and the efficacy of CasIII-ia in the treatment of mice infected with L. mexicana. Results Our results show that CasIII-ia reduces parasite viability in a dose-dependent manner that correlates with increased ROS production. A decrease in the size of footpad lesions and in parasite loads was observed in infected mice treated with the intraperitoneal administration of CasIII-ia. Conclusions We propose CasIII-ia as a potential drug for the treatment of cutaneous leishmaniasis.

Biological activity of mixed chelate copper(II) complexes, with substituted diimine and tridentate Schiff bases (NNO) and their hydrogenated derivatives as secondary ligands: Casiopeína's fourth generation.

We synthesize and characterize nine copper(II) compounds. Four with general formula [Cu(NNO)(NO3)] and five mixed chelates [Cu(NNO)(N-N)]+, where NNO corresponds to asymmetric salen ligands (E)-2-((2-(methylamino)ethylimino)methyl)phenolate (L1) and (E)-3-((2-(methylamino)ethylimino)methyl)naphthalenolate (LN1); and their hydrogenated derivatives 2-((2-(methylamino)ethylamino)methyl)phenolate (LH1) and 3-((2-(methylamino)ethylamino)methyl)naphthalenolate (LNH1); and N-N correspond to 4,4'-dimethyl-2,2'-bipiridyne(dmbpy) or 1,10-phenanthroline (phen). Using EPR, the geometries of the compounds in solution in DMSO were assigned, [Cu(LN1)(NO3)] and [Cu(LNH1)(NO3)] a square-planar, [Cu(L1)(NO3)], [Cu(LH1)(NO3)], [Cu(L1)(dmby)]+ and [Cu(LH1)(dmby)]+ a square-based pyramid; and [Cu(LN1)(dmby)]+, [Cu(LNH1)(dmby)]+ and [Cu(L1)(phen)]+ and elongated octahedral. By X-ray it was observed that [Cu(L1)(dmby)]+ and. [Cu(LN1)(dmby)]+ presented a square-based pyramidal, and [Cu(LN1)(NO3)]+ a square-planar geometry. The electrochemical study showed that copper reduction process is a quasi-reversible system, where the complexes with hydrogenated ligands were less oxidizing. The cytotoxicity of the complexes was tested by MTT assay, all the compounds showed biological activity in HeLa cell line, the mixed compounds were the more active ones. Naphthalene moiety, imine hydrogenation and aromatic diimine coordination, increased biological activity. A structure-activity relationships were found: Log(IC50) =  - 1.01(Epc) - 0.35(Conjugated Rings) + 0.87, for Schiff base complexes and Log(IC50) = 0.078(Epc) - 0.32(Conjugated Rings) + 1.94, for hydrogenated complexes; the less oxidizing species with a great number of conjugated rings presented the best biological activity. Complexes-DNA binding constants were obtained by uv-vis studies using CT-DNA, the results suggested that the complexes can interact through the grooves, except the phenanthroline mixed complex that intercalate with DNA. Gel electrophoresis study with pBR 322 showed that compounds can produce changes in the form of DNA and some complexes can cleave DNA in the presence of H2O2.

Development and In Vitro and In Vivo Evaluation of an Antineoplastic Copper(II) Compound (Casiopeina III-ia) Loaded in Nonionic Vesicles Using Quality by Design.

In recent decades, the interest in metallodrugs as therapeutic agents has increased. Casiopeinas are copper-based compounds that have been evaluated in several tumor cell lines. Currently, casiopeina III-ia (CasIII-ia) is being evaluated in phase I clinical trials. The aim of the present work is to develop a niosome formulation containing CasIII-ia for intravenous administration through a quality-by-design (QbD) approach. Risk analysis was performed to identify the factors that may have an impact on CasIII-ia encapsulation. The developed nanoformulation optimized from the experimental design was characterized by spectroscopy, thermal analysis, and electronic microscopy. In vitro drug release showed a burst effect followed by a diffusion-dependent process. The niosomes showed physical stability for at least three months at 37 °C and 75% relative humidity. The in vitro test showed activity of the encapsulated CasIII-ia on a metastatic breast cancer cell line and the in vivo test of nanoencapsulated CasIII-ia maintained the activity of the free compound, but showed a diminished toxicity. Therefore, the optimal conditions obtained by QbD may improve the scaling-up process.

Casiopeinas® third generation, with indomethacin: synthesis, characterization, DFT studies, antiproliferative activity, and nanoencapsulation.

Seven new Casiopeinas® were synthesized and properly characterized. These novel compounds have a general formula [Cu(N-N)(Indo)]NO3, where Indo is deprotonated indomethacin and N-N is either bipyridine or phenanthroline with some methyl-substituted derivatives, belonging to the third generation of Casiopeinas®. Spectroscopic characterization suggests a square-based pyramid geometry and voltammetry experiments indicate that the redox potential is strongly dependent on the N-N ligand. All the presented compounds show high cytotoxic efficiency, and most of them exhibit higher efficacy compared to the well-known cisplatin drug and acetylacetonate analogs of the first generation. Computational calculations show that antiproliferative behavior can be directly related to the volume of the molecules. Besides, a chitosan (CS)-polyacrylamide (PNIPAAm) nanogel was synthesized and characterized to examine the encapsulation and release properties of the [Cu(4,7-dimethyl-1,10-phenanthroline)(Indo)]NO3 compound. The results show good encapsulation performance in acidic conditions and a higher kinetic drug release in acidic media than at neutral pH. This result can be described by the Peppas-Sahlin model and indicates a release mechanism predominantly by Fick diffusion.

Casiopeinas of Third Generations: Synthesis, Characterization, Cytotoxic Activity and Structure-Activity Relationships of Mixed Chelate Compounds with Bioactive Secondary Ligands.

Casiopeinas are a family of copper(II) coordination compounds that have shown an important antineoplastic effect and low toxicity in normal cells. These compounds induce death cells by apoptosis through a catalytic redox process with endogenous reducing agents. Further studies included a structural variation, improving the activity and selectivity in cancer cells or other targets. In the present work we report the third generation, which contains a bioactive monocharged secondary ligand, as well as the design, synthesis, characterization and antiproliferative activity, of sixteen new copper(II) coordination compounds with curcumin or dimethoxycurcumin as secondary ligands. All compounds were characterized by elemental analysis, FTIR, UV-Vis, magnetic susceptibility, mass spectra with MALDI-flight time, cyclic voltammetry, electron paramagnetic resonance (EPR) spectroscopy and X-ray diffraction. Crystallization of two complexes was achieved in dimethylsulfoxide (DMSO) with polar solvent, and crystal data demonstrated that a square-based or square-base pyramid geometry are possible. A 1:1:1 stoichiometry (diimine: copper: curcuminoid) ratio and the possibility of a nitrate ion as a counterion were supported. 1H, 13C NMR spectra were used for the ligands. A sulforhodamine B assay was used to evaluate the cytotoxicity effect against two human cancer cell lines, SKLU-1 and HeLa. Electronic descriptors and redox potential were obtained by DFT calculations. Structure-activity relationships are strongly determined by the redox potential (E1/2) of copper(II) and molar volume (V) of the complexes. These compounds can be used as a template to open a wide field of research both experimentally and theoretically.

Self-Assembled Monolayer of Monomercaptoundecahydro-closo-dodecaborate on a Polycrystalline Gold Surface.

In this work, we present an electrochemical study of the boron cage monomercaptoundecahydro-closo-dodecaborate [B12H11SH]2- in solution and in a self-assembled monolayer over a polycrystalline gold electrode. Cyclic voltammetry of the anion [B12H11SH]2- in solution showed a shift in the peak potentials related to the redox processes of gold hydroxides, which evidences the interaction between the boron cage and the gold surface. For an Au electrode modified with the anion [B12H11SH]2-, cyclic voltammetry response of the probe Fe(CN)63-/Fe(CN)64- showed a ΔEp value typical for a surface modification. Electrochemical impedance spectroscopy presented Rtc and Cdl values related to the formation of a self-assembled monolayer (SAM). A comparison of electrochemical responses of a modified electrode with thioglycolic acid (TGA) reveals that the boron cage [B12H11SH]2- diminishes the actives sites over the Au surface due to the steric effects. Differential capacitance measurements for bare gold electrode and those modified with [B12H11SH]2- and (TGA), indicate that bulky thiols enhance charge accumulation at the electrode-solution interface. In addition to electrochemical experiments, DFT calculations and surface plasmon resonance measurements (SPR) were carried out to obtain quantum chemical descriptors and to evaluate the molecular length and the dielectric constant of the Boron cage. From SPR experiments, the adsorption kinetics of [B12H11SH]2- were studied. The data fit for a Langmuir kinetic equation, typical for the formation of a monolayer.

Bridging informatics and medicinal inorganic chemistry: Toward a database of metallodrugs and metallodrug candidates.

Metallodrug discovery has evolved in recent years, yielding several compounds in the clinic for therapeutic and medical imaging diagnostic applications. As reviewed here, several research groups in well-established medicinal inorganic chemistry groups are consistently generating high-quality SAR data representing an ideal starting point in the use of computational methods to advance the development of new drugs. Although there are representative chemical structures of metallodrugs in public databases annotated with biological activity, there is currently no public compound database dedicated to metallodrugs. Here, we also discuss the significance, viability, applications and challenges of developing a public compound database of metallodrugs - with consistent representation of metallodrug structure being a crucial obstacle. A curated metallo-compound database would substantially benefit metallodrug discovery and development.

DNA, a target of mixed chelate copper(II) compounds (Casiopeinas®) studied by electrophoresis, UV-vis and circular dichroism techniques.

Casiopeinas are a family of mixed chelate copper(II) complexes with antiproliferative and antineoplastic activities, results that have positioned them as an alternative for cancer treatment. Because DNA is one of their principal targets, it is of our interest to find out the effect of substituents on the diiamine ligands over mode of interaction. Therefore, we studied 21 Casiopeinas upon DNA by gel electrophoresis, UV-vis and circular dichroism (CD) spectroscopic techniques, previously studied by DFT calculations and Quantitative Structure-Activity Relationship (QSAR). According to electrophoresis results, the interaction modes between Casiopeinas with DNA may be through the intercalation or in the minor groove. UV-vis spectroscopy showed a hypochromic or hyperchromic effect as a consequence of each interaction. The analysis suggests the binding along the minor groove and intercalation are both influenced by the substituents in the diimine ligands and depend on the nature of the secondary moiety (acetylacetonate or glycinate). Additionally, a new band in electrophoresis and CD spectra suggests adducts formation. In general, we prove that molecules with the highest molecular weight, electron donating substituents and glycinate as secondary ligand are intercalating agents; unlike molecules with electron withdrawing substituents as chloride or nitro and acetylacetonate as secondary ligand which interact in the minor groove.

Metallodrugs: an approach against invasion and metastasis in cancer treatment.

Cancer is a heterogeneous and multifactorial disease that causes high mortality throughout the world; therefore, finding the most effective therapies is a major research challenge. Currently, most anticancer drugs present a limited number of well-established targets, such as cell proliferation or death; however, it is important to consider that the worse progression of cancer toward pathological stages implies invasion and metastasis processes. Medicinal Inorganic Chemistry (MIC) is a young area that deals with the design, synthesis, characterization, preclinical evaluation, and mechanism of action of new inorganic compounds, called metallodrugs. The properties of metallic ions allow enriching of strategies for the design of new drugs, enabling the adjustment of physicochemical and stereochemical properties. Metallodrugs can adopt geometries, such as tetrahedral, octahedral, square planar, and square planar pyramid, which adjusts their arrangement and facilitates binding with a wide variety of targets. The redox properties of some metal ions can be modulated by the presence of the bound ligands to adjust their interaction, thereby opening a range of mechanisms of action. In this regard, the mechanisms of action that trigger the biological activity of metallodrugs have been generally identified by: (a) coordination of the metal to biomolecules (for instance, cisplatin binds to the N7 in DNA guanine, as Pt-N via coordination of the inhibition of enzymes); (b) redox-active; and (c) ROS production. For this reason, a series of metallodrugs can interact with several specific targets in the anti-invasive processes of cancer and can prevent metastasis. The structural base of several metal compounds shows great anticancer potential by inhibiting the signaling pathways related to cancer progression. In this minireview, we present the advances in the field of antimetastatic effects of metallodrugs.

BAX But Not BCL2 Is Necessary for Apoptosis in Neuroblastoma Cells Treated With Casiopeína® IIIia.

BACKGROUND/AIM: The emerging antineoplastics Casiopeínas® induce uncoupling of the respiratory chain, production of reactive oxygen species (ROS), entry of Bax into mitochondria, and exit of Ca2+ and Bcl-2 from them, leading to apoptosis. This study aimed to elucidate whether BAX and BCL2 are necessary for apoptosis. MATERIALS AND METHODS: We silenced BAX and BCL2 by CRISPR-Cas9, assessed ROS and calcium retention capacity (CRC) by spectrofluorometry, and caspase-3 with inmunoblotting in neuroblastoma (NB) cells and 3T3-L1 fibroblasts treated with cisplatin and Casiopeína IIIia (CasIIIia). RESULTS: We observed an increase in O2•- production only in BCL2KO NB cells treated with cisplatin (three-fold) and CasIIIia (five-fold), whereas the production of H2O2 in BCL2KO NB cells treated with cisplatin and CasIIIia increased five-fold and three-fold, respectively. The baseline calcium-retention capacity (CRC) was 1.7 relative fluorescence units (RFU) in both cell types. In BAXKO, cisplatin and CasIIIia increased CRC to ~2.3 RFU, and in BCL2KO, they decreased CRC to ~1.1 RFU. We did not detect caspase-3 in BAXKO NB cells. CONCLUSION: Only BAX is essential for CasIIIia-induced apoptosis.

1H -NMR Metabolomics Study of the Effect of Cisplatin and Casiopeina IIgly on MDA-MB-231 Breast Tumor Cells.

The knowledge of the metabolic processes of designed metallodrugs for cancer treatment is an area that has been not profoundly studied. Casiopeina IIgly (CasIIgly), which belongs to the Casiopeínas® family, is a copper (II) coordination compound that has shown good biological activity against several cancer cells, low toxicity in normal cells, and antineoplastic activity in in vivo murine and xenografted models. In this work we employed a triple-negative highly metastatic breast carcinoma line (MDA-MB-231), which is one of the cancer types with a great mortality index, for 1H-NMR metabolomic analysis using cisplatin and CasIIgly, in order to quantify the effect of metallodrugs in the metabolic profile of this cell tumor line as a consequence of treatment at different times. Our findings indicate that cisplatin mainly contributes to phospholipid biosynthesis while CasIIgly affects processes such as carbohydrates and nucleotides metabolism. Also, we observed that CasIIgly treatment has an important and fast effect over MDA-MB-231 cell metabolism, which makes it a good alternative for treatment in this type of cancer.

Intermediate Detection in the Casiopeina-Cysteine Interaction Ending in the Disulfide Bond Formation and Copper Reduction.

A strategy to improve the cancer therapies involves agents that cause the depletion of the endogenous antioxidant glutathione (GSH), increasing its efflux out of cells and inducing apoptosis in tumoral cells due to the presence of reactive oxygen species. It has been shown that Casiopeina copper complexes caused a dramatic intracellular GSH drop, forming disulfide bonds and reducing CuII to CuI. Herein, through the determination of the [CuII]-SH bond before reduction, we present evidence of the adduct between cysteine and one Casiopeina as an intermediate in the cystine formation and as a model to understand the anticancer activity of copper complexes. Evidence of such an intermediate has never been presented before.

Anti-proliferative, pro-apoptotic and anti-invasive effect of the copper coordination compound Cas III-La through the induction of reactive oxygen species and regulation of Wnt/ß-catenin pathway in glioma.

Gliomas are the most aggressive neoplasms that affect the central nervous system, being glioblastoma multiforme (GBM) the most malignant. The resistance of GBM to therapies is attributed to its high rate of cell proliferation, angiogenesis, invasion, and resistance to apoptosis; thus, finding alternative therapeutic approaches is vital. In this work, the anti-proliferative, pro-apoptotic, and anti-invasive effect of the copper coordination compound Casiopeina III-La (Cas III-La) on human U373 MG cells was determined in vitro and in vivo. Our results indicate that Cas III-La exerts an anti-proliferative effect, promoting apoptotic cell death and inactivating the invasive process by generating reactive oxygen species (ROS), inactivating GSK3ß, activating JNK and ERK, and promoting the nuclear accumulation of ß-catenin. The inhibition of ROS generation by N-acetyl-l-cysteine not only recovered cell migration and viability, but also reduced ß-catenin accumulation and JNK and ERK activation. Additionally, Cas III-La significantly reduced tumor volume, cell proliferation and mitotic indices, and increased the apoptotic index in mice xenotransplanted with U373 glioma cells. Thus, Cas III-La is a promising agent to treat GBM.

Ancillary Ligand in Ternary CuII Complexes Guides Binding Selectivity toward Minor-Groove DNA.

Copper-containing compounds known as Casiopeínas are biologically active molecules which show promising antineoplastic effects against several cancer types. Two possible hypotheses regarding the mode of action of the Casiopeínas have emerged from the experimental evidence: the generation of reactive oxygen species or the ability of the compounds to bind and interact with nucleic acids. Using robust molecular dynamics simulations, we investigate the interaction of four different Casiopeínas with the DNA duplex d(GCACGAACGAACGAACGC). The studied copper complexes contain either 4-7- or 5-6-substituted dimethyl phenanthroline as the primary ligand and either glycinate or acetylacetonate as the secondary ligand. For statistical significance and to reduce bias in the simulations, four molecules of each copper compound were manually placed at a distance of 10 Å away from the DNA and 20 independent molecular dynamics simulations were performed, each reaching at least 30 µs. This time scale allows us to reproduce expected DNA terminal base-pair fraying and also to observe intercalation/base-pair eversion events generated by the compounds interacting with DNA. The results reveal that the secondary ligand is the guide toward the mode of binding between the copper complex and DNA in which glycinate prefers minor-groove binding and acetylacetonate produces base-pair eversion and intercalation. The CuII complexes containing glycinate interact within the DNA minor groove which are stabilized principally by the hydrogen bonds formed between the amino group of the aminoacidate moiety, whereas the compounds with the acetylacetonate do not present a stable network of hydrogen bonds and the ligand interactions enhance DNA breathing dynamics that result in base-pair eversion.

Theoretical determination of half-wave potentials for phenanthroline-, bipyridine-, acetylacetonate-, and glycinate-containing copper (II) complexes.

We report a protocol for the evaluation of theoretical half-wave potential (E1/2) using a set of 22 mixed chelate copper (II) complexes containing 1,10-phenanthroline and 2,2'-bipyridine derivatives as primary ligands, and acetylacetonate or glycinate as secondary ligands (formally from the Casiopeínas® family) for which accurate experimental values were determined in a 2/5 mixture of ethanol/water. We have calibrated the BP86, PBE, PBE0, B3LYP, M06-2X, and ω-B97XD functionals, using the Los Alamos LANL2DZ and Stuttgart-Köln SDDAll effective core potentials for the Cu and Fe atoms and the 6-311+G* basis set for the C, H, O, and N atoms. To address the solvent effects, we have saturated the first solvation shell with up to 9 water molecules for the explicit model and compared it with the Continuum Like-Polarizable Continuum Model (CPCM) implicit solvent scheme. We found that the PBE/LANL2DZ-6-311+G* protocol (with the CPCM implicit solvent scheme with an effective dielectric constant ε = 64.9121 for the 2/5 mixture of ethanol/water) yields the overall best performance. The theoretical values are compared with experimental data, three of which are reported here for the first time. We find good correlations between the theoretical and experimental E1/2 values for the 2,2'-bipyridine derivatives (R2 = 0.987, MAE = 86 mV) and 1,10-phenanthroline derivatives (R2 = 0.802, MAE = 58.4 mV). The correlation trends have been explained in terms of the copper atom's ability to be reduced in the presence of the ligands. The Gibbs free energy differences at 298 K obtained for the redox reactions show that the more flexible secondary ligands (acetylacetonate) lead to larger entropic contributions which, as expected, increase the average MAE values as compared with the more rigid ligands (glycine). The present protocol yields lower MAEs as compared with previous approaches for similar mixed and flexible Cu(II) complexes.

Heteroleptic NiII complexes: Synthesis, structural characterization, computational studies and amoebicidal activity evaluation.

In this work, we present the synthesis, characterization, electrochemical studies, DFT calculations, and in vitro amoebicidal effect of seven new heteroleptic NiII coordination compounds. The crystal structures of [H2(pdto)](NO3)2 and [Ni(pdto)(NO3)]PF6 are presented, pdto = 2,2'-[1,2-ethanediylbis-(sulfanediyl-2,1-ethanediyl)]dipyridine. The rest of the compounds have general formulae: [Ni(pdto)(NN)](PF6) where N-N = 2,2'-bipyridine (bpy), 4,4'-dimethyl-2,2'-bipyridine (44dmbpy), 5,5'-dimethyl-2,2'-bipyridine (55dmbpy), 1,10-phenanthroline (phen), 4,7-dimethyl-1,10-phenanthroline (47dmphen) and 5,6-dimethyl-1,10-phenanthroline (56dmphen). The size of NN ligand and its substituents modulate the compound electronic features and influence their antiproliferative efficiency against Entamoeba histolytica. 56dmphen derivative, shows the biggest molar volume and presents a powerful amoebicidal activity (IC50 = 1.2 µM), being seven times more effective than the first-line drug for human amoebiasis metronidazole. Also, increases the reactive oxygen species concentration within the trophozoites. This could be the trigger of the E. histolytica growth inhibition. The antiparasitic effect is described using NiII electron density, molar volume, estimated by DFT, as well as the experimental redox potential and diffusion coefficients. In general, amoebicidal efficiency is directly proportional to the increment of the molar volume and decreases when the redox potential becomes more positive.

Identification of descriptors for structure-activity relationship in ruthenium (II) mixed compounds with antiparasitic activity.

Herein is presented the synthesis, characterization, electrochemical studies, DFT calculations and in vitro evaluation of amoebicidal activity in trophozoites of Entamoeba histolytica of twenty ruthenium (II) mixed compounds with general formulae: [Ru(pdto)(E-E)]Clx (E-E bidentate, either neutral or negatively charged ligands). For compounds under study, O-O, N-O and N-N auxiliary donor ligands demonstrate to have a crucial impact on the electronic properties and that it is possible to modulate the antiparasitic activity. Among analyzed complexes, only four present a better performance compared to typically used metronidazole drug (IC50 < 6.80 µmol/L) to treat amebiasis disease. For studied compounds, structure-activity relationships are strongly determined by either the redox potential (E1/2) of RuII/RuIII and calculated molar volume (V) of the complexes.

Autophagy Promotes Survival of CHP-212 Neuroblastoma Cells Treated With Casiopeínas®.

BACKGROUND: Neuroblastoma is the main solid extracranial tumor of childhood. The amplification of N-myc oncogene (MYCN) and 1p deletion are the main molecular alterations. These features are what make treatment impossible, especially in high-risk patients with metastases. MATERIALS AND METHODS: Our study investigated the processes undergone by CHP-212 neuroblastoma cells, after being treated with Casiopeínas® (Cas) IIgly, IIIEa, and IIIia for 2, 10, and 24 h. RESULTS: At 2 h, all the treatments Ied to apoptosis [defined by the presence of B-cell lymphoma 2 (BCL2), BCL2-associated X protein, cytochrome c, and caspase-3]. In addition, autophagy with specific molecules beclin-1 and microtubule-associated protein 1A/1B-light chain 3 (LC3)-II/LC3-I (ratio >1). Later at 10 h, autophagy-associated proteins were observed, and at 24 h, only survival proteins nuclear factor kappa-light-chain-enhancer of activated B-cells (NF-κB), and extracellular signal-regulated kinases (ERK)2/ERK1>1 were found. Another relevant finding was the presence of caspase-10 throughout the study, especially in cells treated with CasIIgly and CasIIIEa. CONCLUSION: These relationships indicate a possible mechanism of action of Casiopeínas on neuroblastoma.

Antigiardiasic activity of Cu(II) coordination compounds: Redox imbalance and membrane damage after a short exposure time.

Giardiasis is a widespread illness that affects inhabitants of underdeveloped countries, being children and seniors the highest risk population. The several adverse effects produced by current therapies besides its increasing ineffectiveness due to the appearance of resistant strains evidence the urgent need for new therapeutic approaches. We present the antigiardiasic effect of eight Cu(II) coordination compounds, which belong to the family Casiopeínas. Two of them, 4,7-diphenyl-1,10-phenanthroline(acetylacetonato)copper(II) nitrate (CasIII-Ha,36 µM) and 4,7-diphenyl-1,10-phenanthroline(glycinato)copper(II) nitrate (CasI-gly,36 µM) have shown the best antiproliferative effect in Giardia intestinalis trophozoite cultures, both with the higher lipophilic character of the series. The antiproliferative effect of these coordination compounds is attributable to its capacity to interact with the cellular membrane and to increase reactive oxygen species (ROS) concentration within the parasite since the first hours of exposure, (2-6 h). We found that these compounds mainly induced the cell death of trophozoites by apoptosis, contrary to metronidazole, which induces apoptosis and necrosis in the same ratio. The cytotoxic effects on lymphocytes and macrophages isolated from human peripheral blood allowed us to establish a selectivity index and in turn, identify and propose the best candidates to continue with the assays in animal models. The selected molecules do not include the most active compounds against trophozoites, instead of that, we propose the compounds 4',4'-dimethyl-2,2'-bipyridine(acetylacetonato)copper(II) nitrate (CasIII-ia,IC50 = 156 µM) and 4,7-dimethyl-1,10-phenanthroline(acetylacetonato) copper(II) nitrate (CasIII-Ea,IC50 = 125 µM), which possess an antiproliferative efficacy comparable with Metronidazole but also are those that produce the lowest effect on the viability of human lymphocytes and macrophages.