RESUMO
Osmium(II) complexes have attractive properties for potential theranostic agents given their anticancer activitiy, their redox potentials favourable for biological transformations within cancer cells and their luminescence in the near infrared (NIR) region. To achieve localised detection and delivery, gold nanoparticles (AuNP) provide an attractive scaffold to attach multiple luminescent agents on a single particle and provide a multimodal platform for detection and loaclaised delivery. We have developed 13 nm and 25 nm AuNP decorated with an osmium complex based on 1,10-phenantholine and surface active bipyridine ligands, OsPhenSS for live cell imaging and singlet oxygen generation, notated as OsPhenSS·AuNP13 and OsPhenSS·AuNP25. The AuNP designs not only allow versatile modalities for localisation of the probe but also water solubility for the osmium metal complex. The osmium decorated nanoparticles OsPhenSS·AuNP13 and OsPhenSS·AuNP25 display characteristic NIR luminescence from the osmium(II) 3MLCT at 785 nm in aqueous solutions with visible excitation. Upon incubation of the nanoparticles in lung cancer and breast carcinoma the luminescence signature of osmium and the gold reflectance reveal localisation in the cytoplasmic and perinuclear compartments. Excitation of the nanoparticles at 552 nm in the presence of a ROS indicator revealed a marked increase in the green fluorescence from the indicator, consistent with photo-induced ROS generation. The detection of singlet oxygen by time-resolved luminescence studies of the osmium and the nanoparticle probes further demonstrates the dual activity of the osmium-based nanoprobes for imaging and therapy. The introduction of gold nanoparticles for carrying osmium imaging probes allows a novel versatile strategy combining detection and localised therapies at the nanoscale.
RESUMO
Cytoglobin is important in the progression of oral squamous cell carcinoma but the molecular and cellular basis remain to be elucidated. In the current study, we develop a new cell model to study the function of cytoglobin in oral squamous carcinoma and response to cisplatin. Transcriptomic profiling showed cytoglobin mediated changes in expression of genes related to stress response, redox metabolism, mitochondrial function, cell adhesion, and fatty acid metabolism. Cellular and biochemical studies show that cytoglobin expression results in changes to phenotype associated with cancer progression including: increased cellular proliferation, motility and cell cycle progression. Cytoglobin also protects cells from cisplatin-induced apoptosis and oxidative stress with levels of the antioxidant glutathione increased and total and mitochondrial reactive oxygen species levels reduced. The mechanism of cisplatin resistance involved inhibition of caspase 9 activation and cytoglobin protected mitochondria from oxidative stress-induced fission. To understand the mechanism behind these phenotypic changes we employed lipidomic analysis and demonstrate that levels of the redox sensitive and apoptosis regulating cardiolipin are significantly up-regulated in cells expressing cytoglobin. In conclusion, our data shows that cytoglobin expression results in important phenotypic changes that could be exploited by cancer cells in vivo to facilitate disease progression.
Assuntos
Apoptose/efeitos dos fármacos , Cardiolipinas/metabolismo , Citoglobina/farmacologia , Mitocôndrias/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Antioxidantes/metabolismo , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Adesão Celular/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Progressão da Doença , Glutationa/metabolismo , Humanos , Mitocôndrias/metabolismo , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/metabolismo , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transcriptoma/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacosRESUMO
Herein we report an in-depth study on the cytotoxic mechanism of action of four developmental cytotoxic copper(ii) complexes: [Cu(phen)2]2+ (Cu-Phen); [Cu(DPQ)(Phen)]2+ (Cu-DPQ-Phen); [Cu(DPPZ)(Phen)]2+; and [Cu(DPPN)(Phen)]2+ (where Phen = 1,10-phenanthroline, DPQ = dipyrido[3,2-f:2',3'-h]quinoxaline, DPPZ = dipyrido[3,2-a:2',3'-c]phenazine, and DPPN = benzo[i]dipyrido[3,2-a:2',3'-c]phenazine). This complex class is known for its DNA intercalative properties and recent evidence-derived from an in vivo proteomic study-supports the potential targeting of mitochondrial function. Therefore, we focused on mitochondrial-mediated apoptosis related to cytotoxic activity and the potential impact these agents have on mitochondrial function. The Cu(ii) complexes demonstrated superior activity regardless of aromatic extension within the phenazine ligand to the previously demonstrated activity of cisplatin. Unique toxicity mechanisms were also identified in prior demonstrated cisplatin sensitive and resistant cell lines. Double strand breaks in genomic DNA, quantified by γH2AX foci formation, were then coupled with apoptotic gene expression to elucidate the mechanisms of cell death. These results indicate that while DNA damage-induced apoptosis by BAX, XIAP and caspase-9 and -3 expression is moderate for the Cu(ii) complexes when compared to cisplatin, protein targets independent of DNA exert a multimodal mechanistic effect. Significantly, mitochondrial gene expression of oxidative stress, protease expression, and fission/fusion processes-upregulated HMOX, DRP1 and LON, respectively-indicated an increased oxidative damage associated with compromised mitochondrial health upon exposure to these agents. These data support a unique mode of action by these complexes and provide valuable evidence of the developmental potential of these therapeutic inorganic complexes.
Assuntos
Cobre/química , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Fenantrolinas/química , Fenantrolinas/farmacologia , Fenazinas/química , Fenazinas/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular , Citometria de Fluxo , Humanos , Células MCF-7 , Microscopia Confocal , Oxirredução/efeitos dos fármacosRESUMO
Herein we report the in-vivo characterisation and metabolic changes in Galleria mellonella larvae to a series of bis-chelate copper(II) phenanthroline-phenazine cationic complexes of [Cu(phen)2]2+ (Cu-Phen), [Cu(DPQ)(Phen)]2+ (Cu-DPQ-Phen) and [Cu(DPPZ)(Phen)]2+ (Cu-DPPZ-Phen) (where phenâ¯=â¯1,10-phenanthroline, DPQâ¯=â¯dipyrido[3,2-ƒ:2',3'-h]quinoxaline and DPPZâ¯=â¯dipyrido[3,2-a:2',3'-c]phenazine). Our aim was to investigate the influence of the systematic extension of the ligated phenazine ligand in the G. mellonella model as a first step towards assessing the in-vivo tolerance and mode of action of the complex series with respect to the well-studied oxidative chemical nuclease, Cu-Phen. The Lethal Dose50 (LD50) values were established over dose ranges of 2 - 30⯵g at 4-, 24-, 48- and 72â¯h by mortality assessment, with Cu-Phen eliciting the highest mortality at 4â¯h (Cu-Phen, 12.62⯵gâ¯<â¯Cu-DPQ-Phen, 21.53⯵gâ¯<â¯Cu-DPPZ-Phen, 26.07⯵g). At other timepoints, a similar profile was observed as the phenazine π-backbone within the complex scaffold was extended. Assessment of both cellular response and related gene expression demonstrated that the complexes did not initiate an immune response. However, Label-Free Quantification proteomic data indicated the larval response was associated with upregulation of key proteins such as Glutathione S-transferase, purine synthesis and glycolysis/gluconeogenesis (e.g. fructose-bisphosphate aldolase and glyceraldehyde-3-phosphate). Both Cu-Phen and Cu-DPQ-Phen elicited a similar in-vivo response in contrast to Cu-DPPZ-Phen, which displayed a substantial increase in nitrogen detoxification proteins and proteins with calcium binding sites. Overall, the response of G. mellonella larvae exposure to the complex series is dominated by detoxification and metabolic proteome response mechanisms.
Assuntos
Cobre , Mariposas/metabolismo , Compostos Organometálicos , Fenantrolinas , Fenazinas , Animais , Cobre/química , Cobre/farmacologia , Avaliação de Medicamentos , Inseticidas/síntese química , Inseticidas/química , Inseticidas/farmacologia , Larva/metabolismo , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Fenantrolinas/química , Fenantrolinas/farmacologia , Fenazinas/química , Fenazinas/farmacologiaRESUMO
The complexes [Ag2(OOC-(CH2)n-COO)] (n=1-10) (1-10) were synthesised and reacted with 1,10-phenanthroline (phen) to yield derivatives formulating as [Ag2(phen)x(OOC-(CH2)y-COO)]·zH2O (x=2 or 3; y=1-10; z=1-4) (11-20) which are highly water-soluble and photo-stable in aqueous solution. The phen derivatives 11-20 exhibit chemotherapeutic potential against Candida albicans, Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa and against cisplatin-sensitive breast (MCF-7) and resistant ovarian (SKOV-3) cancer cell lines. Cyclic voltammetric analysis and DNA binding and intercalation studies indicate that the mechanism of action of 11-20 is significantly different to that of their silver(I) dicarboxylate precursors and they do not induce DNA damage or ROS generation in mammalian cells. The representative complexes 9 and 19 (containing the undecanedioate ligand) were both found to significantly reduce superoxide and hydrogen peroxide induced oxidative stress in the yeast S. cerevisiae.
Assuntos
Anti-Infecciosos , Antineoplásicos , Bactérias/crescimento & desenvolvimento , Neoplasias da Mama/tratamento farmacológico , Candida albicans/crescimento & desenvolvimento , Neoplasias Ovarianas/tratamento farmacológico , Fenantrolinas , Prata , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Humanos , Substâncias Intercalantes/síntese química , Substâncias Intercalantes/química , Substâncias Intercalantes/farmacologia , Células MCF-7 , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Fenantrolinas/síntese química , Fenantrolinas/química , Fenantrolinas/farmacologia , Saccharomyces cerevisiae/metabolismo , Prata/química , Prata/farmacologia , SolubilidadeRESUMO
The synthetic chemical nuclease, [Cu(1,10-phenanthroline)2](2+), has stimulated research within metallonuclease development and in the area of cytotoxic metallodrug design. Our analysis reveals, however, that this agent is "promiscuous" as it binds both dsDNA and protein biomolecules, without specificity, and induces general toxicity to a diversity of cell lineages. Here, we describe the synthesis and characterization of small-molecule metallonucleases containing the redox-active cation, [Cu(RCOO)(1,10-phen)2](+), where 1,10-phen = 1,10-phenanthroline and R = -H, -CH3, -C2H5, -CH(CH3)2, and -C(CH3)3. The presence of coordinated carboxylate groups in the complex cation functions to enhance dsDNA recognition, reduce serum albumin binding, and offer control of toxicity toward human cancer cells, Gram positive and negative bacteria, and fungal pathogens. The induction of genomic dsDNA breaks (DSBs) were identified in ovarian adenocarcinoma cells using immunodetection of γ-H2AX. Formate, acetate, and pivalate functionalized complexes induced DSBs in a higher percentage of cells compared with [Cu(1,10-phen)2](2+), which supports the importance of inner-sphere modification toward enhancing targeted biological application.