Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 60
Filtrar
1.
Chempluschem ; 89(4): e202300557, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37937471

RESUMO

A dinuclear gold(I) complex featuring a strongly donating bis-N-heterocyclic imine ligand was synthesised and characterised by different methods, including single crystal X-ray diffraction (SC-XRD) analysis. The compound has been tested for its antiproliferative effects in a panel of human cancer cell lines in vitro, showing highly selective anticancer effects, particularly against human A549 non-small cell lung cancer cells (NSCLC), with respect to non-tumorigenic cells (VERO). The accumulation of the compound in A549 and VERO cells was studied by high-resolution continuum source atomic absorption spectrometry (HRCS-AAS), revealing that the anticancer effects are not particularly related to the different amounts of gold taken up by the cells over 72 h. Enzyme inhibition studies to evaluate the activity of the seleno-enzyme thioredoxin reductase (TrxR) in cancer cell extracts show that the gold(I) compound is a potent inhibitor (IC50=0.567±0.208 µM), while the free ligand is ineffective. This result correlates with the observed compound's selectivity towards A549 cells overexpressing the enzyme.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Animais , Chlorocebus aethiops , Humanos , Ouro/química , Tiorredoxina Dissulfeto Redutase/metabolismo , Linhagem Celular Tumoral , Ligantes , Células Vero
2.
Cell Rep Med ; 4(11): 101249, 2023 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-37883975

RESUMO

The isocitrate dehydrogenase (IDH) gene is recurrently mutated in adult diffuse gliomas. IDH-mutant gliomas are categorized into oligodendrogliomas and astrocytomas, each with unique pathological features. Here, we use single-nucleus RNA and ATAC sequencing to compare the molecular heterogeneity of these glioma subtypes. In addition to astrocyte-like, oligodendrocyte progenitor-like, and cycling tumor subpopulations, a tumor population enriched for ribosomal genes and translation elongation factors is primarily present in oligodendrogliomas. Longitudinal analysis of astrocytomas indicates that the proportion of tumor subpopulations remains stable in recurrent tumors. Analysis of tumor-associated microglia/macrophages (TAMs) reveals significant differences between oligodendrogliomas, with astrocytomas harboring inflammatory TAMs expressing phosphorylated STAT1, as confirmed by immunohistochemistry. Furthermore, inferred receptor-ligand interactions between tumor subpopulations and TAMs may contribute to TAM state diversity. Overall, our study sheds light on distinct tumor populations, TAM heterogeneity, TAM-tumor interactions in IDH-mutant glioma subtypes, and the relative stability of tumor subpopulations in recurrent astrocytomas.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Glioma , Oligodendroglioma , Humanos , Oligodendroglioma/genética , Oligodendroglioma/patologia , Neoplasias Encefálicas/genética , Microglia/patologia , Mutação , Recidiva Local de Neoplasia/genética , Glioma/genética , Glioma/patologia , Astrocitoma/genética , Isocitrato Desidrogenase/genética
3.
Inorg Chem ; 62(50): 20710-20720, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-37556427

RESUMO

Self-assembled supramolecular coordination complexes (SCCs) hold promise for biomedical applications in cancer therapy, although their potential in the field of nuclear medicine is still substantially unexplored. Therefore, in this study an exo-functionalized cationic [Pd2L2]4+ metallacycle (L = 3,5-bis(3-ethynylpyridine)phenyl), targeted to the somatostatin-2 receptor (sst2R) and featuring the DOTA chelator (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) in order to bind the ß-- and γ-emitter lutetium-177, was synthesized by self-assembly following ligand synthesis via standard solid-phase peptide synthesis (SPPS). This metallacycle was then characterized by reverse-phase high-performance liquid chromatography (RP-HPLC), electrospray ionization mass spectrometry (ESI-MS), and 1H and 1H-DOSY NMR (DOSY = diffusion-ordered spectroscopy). A procedure for the radiolabeling of the metallacycle with 177Lu was also optimized. The resulting [nat/177Lu]Lu-DOTA-metallacycle, termed [nat/177Lu]Lu-Cy, was evaluated concerning its stability and in vitro properties. The compound was more lipophilic compared to the reference [177Lu]Lu-DOTA-TATE (logPOct/H2O = -0.85 ± 0.10 versus -3.67 ± 0.04, respectively). While [natLu]Lu-Cy revealed low stability in a DMEM/F12 GlutaMax medium, it demonstrated good stability in other aqueous media as well as in DMSO. A high sst2R binding affinity (expressed as IC50) was determined in CHOsst2 cells (Chinese hamster ovary cells that were stably transfected with human sst2R). Moreover, the metallacycle exhibited high human serum albumin binding, as assessed by high-performance affinity chromatography (HPAC), and moderate stability in human serum compared to [177Lu]Lu-DOTA-TATE (TATE = (Tyr3)-octreotate). In order to improve stability, a heteroleptic approach was used to develop a less sterically hindered cage-like SCC that is potentially endowed with host-guest chemistry capability, which has been preliminarily characterized by RP-HPLC and ESI-MS. Overall, our initial results encourage future studies on sst2R-directed SCCs and have led to new insights into the chemistry of ss2R-directed SCCs for radiopharmaceutical applications.


Assuntos
Medicina Nuclear , Compostos Radiofarmacêuticos , Animais , Cricetinae , Humanos , Células CHO , Cricetulus , Compostos Radiofarmacêuticos/uso terapêutico , Compostos Radiofarmacêuticos/química , Lutécio/química , Medicina Nuclear/métodos , Somatostatina
4.
J Med Chem ; 66(6): 3995-4008, 2023 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-36898000

RESUMO

Treatment of triple-negative breast cancer (TNBC) has long been a medical challenge because of the lack of effective therapeutic targets. Targeting lipid, carbohydrate, and nucleotide metabolism pathways has recently been proven as a promising option in view of three heterogeneous metabolic-pathway-based TNBC subtypes. Here, we present a multimodal anticancer platinum(II) complex, named Pt(II)caffeine, with a novel mode of action involving simultaneous mitochondrial damage, inhibition of lipid, carbohydrate, and nucleotide metabolic pathways, and promotion of autophagy. All these biological processes eventually result in a strong suppression of TNBC MDA-MB-231 cell proliferation both in vitro and in vivo. The results indicate that Pt(II)caffeine, influencing cellular metabolism at multiple levels, is a metallodrug with increased potential to overcome the metabolic heterogeneity of TNBC.


Assuntos
Platina , Neoplasias de Mama Triplo Negativas , Humanos , Platina/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Cafeína/uso terapêutico , Linhagem Celular Tumoral , Carboidratos/farmacologia , Nucleotídeos/farmacologia , Lipídeos/farmacologia , Proliferação de Células , Apoptose
5.
Angew Chem Int Ed Engl ; 62(10): e202217233, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36628505

RESUMO

AuI -carbene and PtIV -AuI -carbene prodrugs display low to sub-µM activity against several cancer cell lines and overcome cisplatin (cisPt) resistance. Linking a cisPt-derived PtIV (phenylbutyrate) complex to a AuI -phenylimidazolylidene complex 2, yielded the most potent prodrug. While in vivo tests against Lewis Lung Carcinoma showed that the prodrug PtIV (phenylbutyrate)-AuI -carbene (7) and the 1 : 1 : 1 co-administration of cisPt: phenylbutyrate:2 efficiently inhibited tumor growth (≈95 %), much better than 2 (75 %) or cisPt (84 %), 7 exhibited only 5 % body weight loss compared to 14 % for 2, 20 % for cisPt and >30 % for the co-administration. 7 was much more efficient than 2 at inhibiting TrxR activity in the isolated enzyme, in cells and in the tumor, even though it was much less efficient than 2 at binding to selenocysteine peptides modeling the active site of TrxR. Organ distribution and laser-ablation (LA)-ICP-TOFMS imaging suggest that 7 arrives intact at the tumor and is activated there.


Assuntos
Antineoplásicos , Pró-Fármacos , Antineoplásicos/química , Fenilbutiratos , Pró-Fármacos/química , Linhagem Celular Tumoral , Cisplatino/química
6.
Neuro Oncol ; 25(6): 1031-1043, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-36215168

RESUMO

BACKGROUND: IDH mutant gliomas are grouped into astrocytomas or oligodendrogliomas depending on the codeletion of chromosome arms 1p and 19q. Although the genomic alterations of IDH mutant gliomas have been well described, transcriptional changes unique to either tumor type have not been fully understood. Here, we identify Tripartite Motif Containing 67 (TRIM67), an E3 ubiquitin ligase with essential roles during neuronal development, as an oncogene distinctly upregulated in oligodendrogliomas. METHODS: We used several cell lines, including patient-derived oligodendroglioma tumorspheres, to knock down or overexpress TRIM67. We coupled high-throughput assays, including RNA sequencing, total lysate-mass spectrometry (MS), and coimmunoprecipitation (co-IP)-MS with functional assays including immunofluorescence (IF) staining, co-IP, and western blotting (WB) to assess the in vitro phenotype associated with TRIM67. Patient-derived oligodendroglioma tumorspheres were orthotopically implanted in mice to determine the effect of TRIM67 on tumor growth and survival. RESULTS: TRIM67 overexpression alters the abundance of cytoskeletal proteins and induces membrane bleb formation. TRIM67-associated blebbing was reverted with the nonmuscle class II myosin inhibitor blebbistatin and selective ROCK inhibitor fasudil. NOGO-A/Rho GTPase/ROCK2 signaling is altered upon TRIM67 ectopic expression, pointing to the underlying mechanism for TRIM67-induced blebbing. Phenotypically, TRIM67 expression resulted in higher cell motility and reduced cell adherence. In orthotopic implantation models of patient-derived oligodendrogliomas, TRIM67 accelerated tumor growth, reduced overall survival, and led to increased vimentin expression at the tumor margin. CONCLUSIONS: Taken together, our results demonstrate that upregulated TRIM67 induces blebbing-based rounded cell morphology through Rho GTPase/ROCK-mediated signaling thereby contributing to glioma pathogenesis.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Glioma , Oligodendroglioma , Animais , Camundongos , Humanos , Oligodendroglioma/genética , Proteínas Nogo/genética , Glioma/patologia , Astrocitoma/genética , Transformação Celular Neoplásica , Carcinogênese , Cromossomos Humanos Par 1 , Neoplasias Encefálicas/patologia , Cromossomos Humanos Par 19 , Isocitrato Desidrogenase/genética , Mutação , Proteínas com Motivo Tripartido/genética , Proteínas do Citoesqueleto/genética
7.
Chemistry ; 29(3): e202202604, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36239701

RESUMO

To advance the design of self-assembled metallosupramolecular architectures as new generation theranostic agents, the synthesis of 18 F-labelled [Pd2 L4 ]4+ metallacages is reported. Different spectroscopic and bio-analytical methods support the formation of the host-guest cage-cisplatin complex. The biodistribution profiles of one of the cages, alone or encapsulating cisplatin have been studied by PET/CT imaging in healthy mice in vivo, in combination to ICP-MS ex vivo.


Assuntos
Antineoplásicos , Cisplatino , Camundongos , Animais , Cisplatino/química , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Distribuição Tecidual , Tomografia por Emissão de Pósitrons , Antineoplásicos/química
8.
Inorg Chem ; 61(50): 20405-20423, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36484812

RESUMO

With the aim to improve the design of metal complexes as stabilizers of noncanonical DNA secondary structures, namely, G-quadruplexes (G4s), a series of cyclic dinuclear Au(I) N-heterocyclic carbene complexes based on xanthine and benzimidazole ligands has been synthesized and characterized by various methods, including X-ray diffraction. Fluorescence resonance energy transfer (FRET) and CD DNA melting assays unraveled the compounds' stabilization properties toward G4s of different topologies of physiological relevance. Initial structure-activity relationships have been identified and recognize the family of xanthine derivatives as those more selective toward G4s versus duplex DNA. The binding modes and free-energy landscape of the most active xanthine derivative (featuring a propyl linker) with the promoter sequence cKIT1 have been studied by metadynamics. The atomistic simulations evidenced that the Au(I) compound interacts noncovalently with the top G4 tetrad. The theoretical results on the Au(I) complex/DNA Gibbs free energy of binding were experimentally validated by FRET DNA melting assays. The compounds have also been tested for their antiproliferative properties in human cancer cells in vitro, showing generally moderate activity. This study provides further insights into the biological activity of Au(I) organometallics acting via noncovalent interactions and underlines their promise for tunable targeted applications by appropriate chemical modifications.


Assuntos
Quadruplex G , Humanos , Ligantes , DNA/química , Transferência Ressonante de Energia de Fluorescência , Xantinas
9.
Adv Mater ; 34(40): e2206405, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35977414

RESUMO

Carbon suboxide (C3 O2 ) is a unique molecule able to polymerize spontaneously into highly conjugated light-absorbing structures at temperatures as low as 0 °C. Despite obvious advantages, little is known about the nature and the functional properties of this carbonaceous material. In this work, the aim is to bring "red carbon," a forgotten polymeric semiconductor, back to the community's attention. A solution polymerization process is adapted to simplify the synthesis and control the structure. This allows one to obtain this crystalline covalent material at low temperatures. Both spectroscopic and elemental analyses support the chemical structure represented as conjugated ladder polypyrone ribbons. Density functional theory calculations suggest a crystalline structure of AB stacks of polypyrone ribbons and identify the material as a direct bandgap semiconductor with a medium bandgap that is further confirmed by optical analysis. The material shows promising photocatalytic performance using blue light. Moreover, the simple condensation-aromatization route described here allows the straightforward fabrication of conjugated ladder polymers and can be inspiring for the synthesis of carbonaceous materials at low temperatures in general.

10.
Chem Sci ; 13(23): 6899-6919, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35774173

RESUMO

In vivo data are rare but essential for establishing the clinical potential of ruthenium-based photoactivated chemotherapy (PACT) compounds, a new family of phototherapeutic drugs that are activated via ligand photosubstitution. Here a novel trisheteroleptic ruthenium complex [Ru(dpp)(bpy)(mtmp)](PF6)2 ([2](PF6)2, dpp = 4,7-diphenyl-1,10-phenanthroline, bpy = 2,2'-bipyridine, mtmp = 2-methylthiomethylpyridine) was synthesized and its light-activated anticancer properties were validated in cancer cell monolayers, 3D tumor spheroids, and in embryonic zebrafish cancer models. Upon green light irradiation, the non-toxic mtmp ligand is selectively cleaved off, thereby releasing a phototoxic ruthenium-based photoproduct capable notably of binding to nuclear DNA and triggering DNA damage and apoptosis within 24-48 h. In vitro, fifteen minutes of green light irradiation (21 mW cm-2, 19 J cm-2, 520 nm) were sufficient to generate high phototherapeutic indexes (PI) for this compound in a range of cancer cell lines including lung (A549), prostate (PC3Pro4), conjunctival melanoma (CRMM1, CRMM2, CM2005.1) and uveal melanoma (OMM1, OMM2.5, Mel270) cancer cell lines. The therapeutic potential of [2](PF6)2 was further evaluated in zebrafish embryo ectopic (PC3Pro4) or orthotopic (CRMM1, CRMM2) tumour models. The ectopic model consisted of red fluorescent PC3Pro4-mCherry cells injected intravenously (IV) into zebrafish, that formed perivascular metastatic lesions at the posterior ventral end of caudal hematopoietic tissue (CHT). By contrast, in the orthotopic model, CRMM1- and CRMM2-mCherry cells were injected behind the eye where they developed primary lesions. The maximally-tolerated dose (MTD) of [2](PF6)2 was first determined for three different modes of compound administration: (i) incubating the fish in prodrug-containing water (WA); (ii) injecting the prodrug intravenously (IV) into the fish; or (iii) injecting the prodrug retro-orbitally (RO) into the fish. To test the anticancer efficiency of [2](PF6)2, the embryos were treated 24 h after engraftment at the MTD. Optimally, four consecutive PACT treatments were performed on engrafted embryos using 60 min drug-to-light intervals and 90 min green light irradiation (21 mW cm-2, 114 J cm-2, 520 nm). Most importantly, this PACT protocol was not toxic to the zebrafish. In the ectopic prostate tumour models, where [2](PF6)2 showed the highest photoindex in vitro (PI > 31), the PACT treatment did not significantly diminish the growth of primary lesions, while in both conjunctival melanoma orthotopic tumour models, where [2](PF6)2 showed more modest photoindexes (PI ∼ 9), retro-orbitally administered PACT treatment significantly inhibited growth of the engrafted tumors. Overall, this study represents the first demonstration in zebrafish cancer models of the clinical potential of ruthenium-based PACT, here against conjunctival melanoma.

11.
Dalton Trans ; 51(19): 7476-7490, 2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35470841

RESUMO

With the aim of designing new metallosupramolecular architectures for drug delivery, research has focused on porous 3-dimensional (3D)-metallacages able to encapsulate cytotoxic agents protecting them from metabolism while targeting them to cancer sites. Here, two self-assembled [Pd2L4]4+ cages (CG1 and CG2) featuring 3,5-bis(3-ethynylpyridine)phenyl ligands (L) exo-functionalised with dipyrromethene (BODIPY) groups have been synthesised and characterised by different methods, including NMR spectroscopy and mass spectrometry. 1H NMR spectroscopy studies shows that the cages are able to encapsulate the anticancer drug cisplatin in their hydrophobic cavity, as evidenced by electrostatic potential (ESP) analysis based on XRD studies. The stability of the cages in an aqueous environment, and in the presence of the intracellular reducing agent glutathione, has been confirmed by UV-visible absorption spectroscopy. The luminescence properties of the cages enabled the investigation of their cellular uptake and intracellular localisation in human cancer cells by confocal laser scanning microscopy. In melanoma A375 cells, cage CG1 is taken up via active transport and endocytic trafficking studies show little evidence of transport through the early endosome while the cages accumulated in melanosomes rather than lysosomes. The antiproliferative activity of the lead cage was investigated in A375 together with two breast cancer cell lines, SK-BR-3 and MCF7. While the cage per se is non-cytotoxic, very different antiproliferative effects with respect to free cisplatin were evidenced for the [(cisplatin)2⊂CG1·BF4] complex in the various cell lines, which correlate with its different intracellular localisation profiles. The obtained preliminary results provide a new hypothesis on how the subcellular localisation of the cage affects the cisplatin intracellular release.


Assuntos
Cisplatino , Paládio , Compostos de Boro , Linhagem Celular Tumoral , Cisplatino/química , Cisplatino/farmacologia , Sistemas de Liberação de Medicamentos , Humanos , Paládio/química
12.
Neuro Oncol ; 24(11): 1911-1924, 2022 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-35468210

RESUMO

BACKGROUND: Glioblastoma (GBM) is an aggressive tumor that frequently exhibits gain of chromosome 7, loss of chromosome 10, and aberrantly activated receptor tyrosine kinase signaling pathways. Previously, we identified Mesenchyme Homeobox 2 (MEOX2), a gene located on chromosome 7, as an upregulated transcription factor in GBM. Overexpressed transcription factors can be involved in driving GBM. Here, we aimed to address the role of MEOX2 in GBM. METHODS: Patient-derived GBM tumorspheres were used to constitutively knockdown or overexpress MEOX2 and subjected to in vitro assays including western blot to assess ERK phosphorylation. Cerebral organoid models were used to investigate the role of MEOX2 in growth initiation. Intracranial mouse implantation models were used to assess the tumorigenic potential of MEOX2. RNA-sequencing, ACT-seq, and CUT&Tag were used to identify MEOX2 target genes. RESULTS: MEOX2 enhanced ERK signaling through a feed-forward mechanism. We identified Ser155 as a putative ERK-dependent phosphorylation site upstream of the homeobox-domain of MEOX2. S155A substitution had a major effect on MEOX2 protein levels and altered its subnuclear localization. MEOX2 overexpression cooperated with p53 and PTEN loss in cerebral organoid models of human malignant gliomas to induce cell proliferation. Using high-throughput genomics, we identified putative transcriptional target genes of MEOX2 in patient-derived GBM tumorsphere models and a fresh frozen GBM tumor. CONCLUSIONS: We identified MEOX2 as an oncogenic transcription regulator in GBM. MEOX2 increases proliferation in cerebral organoid models of GBM and feeds into ERK signaling that represents a core signaling pathway in GBM.


Assuntos
Glioblastoma , Glioma , Camundongos , Animais , Humanos , Genes Homeobox , Proteínas de Homeodomínio/genética , Glioma/genética , Glioblastoma/patologia , Proliferação de Células , Fatores de Transcrição/genética , Carcinogênese/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica
13.
Chem Commun (Camb) ; 58(36): 5526-5529, 2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35420608

RESUMO

With the idea of exploiting metal templated C-S bond forming reactions to achieve modification of cysteines in bacterial proteins, a cyclometalated Au(III) compound was explored in a competitive chemoproteomic approach in S. aureus cell extracts. More than 100 ligandable cysteines were identified, of which more than 50% were not engaged by organic α-chloroacetamides in a previous study, indicating that organometallic compounds expand the ligandable space in bacteria. A selected interaction was validated using an enzyme activity assay, and intact protein mass spectrometry showed cysteine arylation of an unprecedented target. The obtained results demonstrate that this family of organogold compounds has potential for therapeutic protein targeting via selective, covalent modification of cysteine residues in bacteria.


Assuntos
Cisteína , Staphylococcus aureus , Cisteína/química , Compostos Organoáuricos/química
14.
Int J Mol Sci ; 22(24)2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34948263

RESUMO

A series of bifunctional Ru(III) complexes with lonidamine-modified ligands (lonidamine is a selective inhibitor of aerobic glycolysis in cancer cells) was described. Redox properties of Ru(III) complexes were characterized by cyclic voltammetry. An easy reduction suggested a perspective for these agents as their whole mechanism of action seems to be based on activation by metal atom reduction. New compounds demonstrated a more pronounced antiproliferative potency than the parental drug; individual new agents were more cytotoxic than cisplatin. Stability studies showed an increase in the stability of complexes along with the linker length. A similar trend was noted for antiproliferative activity, cellular uptake, apoptosis induction, and thioredoxin reductase inhibition. Finally, at concentrations that did not alter water solubility, the selected new complex evoked no acute toxicity in Balb/c mice.


Assuntos
Indazóis/química , Rutênio/química , Rutênio/farmacologia , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Complexos de Coordenação/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Ligantes , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Oxirredução , Relação Estrutura-Atividade , Tiorredoxina Dissulfeto Redutase/metabolismo
15.
Int J Mol Sci ; 22(19)2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34638879

RESUMO

Colorectal cancer (CRC) is one of the most frequently diagnosed cancers in humans. At early stages CRC is treated by surgery and at advanced stages combined with chemotherapy. We examined here the potential effect of glucosylceramide synthase (GCS)-inhibition on CRC biology. GCS is the rate-limiting enzyme in the glycosphingolipid (GSL)-biosynthesis pathway and overexpressed in many human tumors. We suppressed GSL-biosynthesis using the GCS inhibitor Genz-123346 (Genz), NB-DNJ (Miglustat) or by genetic targeting of the GCS-encoding gene UDP-glucose-ceramide-glucosyltransferase- (UGCG). GCS-inhibition or GSL-depletion led to a marked arrest of the cell cycle in Lovo cells. UGCG silencing strongly also inhibited tumor spheroid growth in Lovo cells and moderately in HCT116 cells. MS/MS analysis demonstrated markedly elevated levels of sphingomyelin (SM) and phosphatidylcholine (PC) that occurred in a Genz-concentration dependent manner. Ultrastructural analysis of Genz-treated cells indicated multi-lamellar lipid storage in vesicular compartments. In mice, Genz lowered the incidence of experimentally induced colorectal tumors and in particular the growth of colorectal adenomas. These results highlight the potential for GCS-based inhibition in the treatment of CRC.


Assuntos
Ciclo Celular/efeitos dos fármacos , Neoplasias do Colo , Dioxanos/farmacologia , Glicoesfingolipídeos , Pirrolidinas/farmacologia , Esferoides Celulares , Animais , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Glucosiltransferases/antagonistas & inibidores , Glucosiltransferases/metabolismo , Glicoesfingolipídeos/biossíntese , Glicoesfingolipídeos/genética , Células HCT116 , Humanos , Camundongos , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/genética , Neoplasias Experimentais/metabolismo , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia
16.
J Med Chem ; 64(15): 11364-11378, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34342437

RESUMO

"Multi-action" Pt(IV) derivatives of cisplatin with combretastatin A4 (CA4) bioactive ligands that are conjugated to Pt(IV) by carbonate are unique because the ligand (IC50 < 10 nM) is dramatically 1000-folds more cytotoxic than cisplatin in vitro. The Pt(IV)-CA4 prodrugs were as cytotoxic as CA4 itself, indicating that the platinum moiety probably plays an insignificant role in triggering cytotoxicity, suggesting that the Pt(IV)-CA4 complexes act as prodrugs for CA4 rather than as true multi-action prodrugs. In vivo tests (Lewis lung carcinoma) show that ctc-[Pt(NH3)2(PhB)(CA4)Cl2] inhibited tumor growth by 93% compared to CA4 (67%), cisplatin (84%), and 1:1:1 cisplatin/CA4/PhB (85%) while displaying <5% body weight loss compared to cisplatin (20%) or CA4 (10%). In this case, and perhaps with other extremely potent bioactive ligands, platinum(IV) acts merely as a self-immolative carrier triggered by reduction in the cancer cell with only a minor contribution to cytotoxicity.


Assuntos
Antineoplásicos/farmacologia , Anidrase Carbônica IV/metabolismo , Compostos Organoplatínicos/farmacologia , Pró-Fármacos/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Anidrase Carbônica IV/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Cricetulus , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Ligantes , Estrutura Molecular , Compostos Organoplatínicos/síntese química , Compostos Organoplatínicos/química , Pró-Fármacos/síntese química , Pró-Fármacos/química , Proibitinas , Relação Estrutura-Atividade
17.
J Biol Inorg Chem ; 26(6): 667-674, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34378103

RESUMO

The known ruthenium complex [Ru(tpy)(bpy)(Hmte)](PF6)2 ([1](PF6)2, where tpy = 2,2':6',2″-terpyridine, bpy = 2,2'-bipyridine, Hmte = 2-(methylthio)ethanol) is photosubstitutionally active but non-toxic to cancer cells even upon light irradiation. In this work, the two analogs complexes [Ru(tpy)(NN)(Hmte)](PF6)2, where NN = 3,3'-biisoquinoline (i-biq, [2](PF6)2) and di(isoquinolin-3-yl)amine (i-Hdiqa, [3](PF6)2), were synthesized and their photochemistry and phototoxicity evaluated to assess their suitability as photoactivated chemotherapy (PACT) agents. The increase of the aromatic surface of [2](PF6)2 and [3](PF6)2, compared to [1](PF6)2, leads to higher lipophilicity and higher cellular uptake for the former complexes. Such improved uptake is directly correlated to the cytotoxicity of these compounds in the dark: while [2](PF6)2 and [3](PF6)2 showed low EC50 values in human cancer cells, [1](PF6)2 is not cytotoxic due to poor cellular uptake. While stable in the dark, all complexes substituted the protecting thioether ligand upon light irradiation (520 nm), with the highest photosubstitution quantum yield found for [3](PF6)2 (Φ[3] = 0.070). Compounds [2](PF6)2 and [3](PF6)2 were found both more cytotoxic after light activation than in the dark, with a photo index of 4. Considering the very low singlet oxygen quantum yields of these compounds, and the lack of cytotoxicity of the photoreleased Hmte thioether ligand, it can be concluded that the toxicity observed after light activation is due to the photoreleased aqua complexes [Ru(tpy)(NN)(OH2)]2+, and thus that [2](PF6)2 and [3](PF6)2 are promising PACT candidates.


Assuntos
Compostos de Rutênio/síntese química , Compostos de Rutênio/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Modelos Moleculares , Estrutura Molecular , Rutênio , Compostos de Rutênio/química
18.
Rev. bras. ciênc. vet ; 27(3): 137-145, jul./set. 2020. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1491675

RESUMO

Devido aos altos índices de resistência dos parasitas aos diferentes princípios ativos comerciais, novas alternativas de controle vêm sendo estudadas, entre elas a fitoterapia. Essas medidas visam a busca de métodos auxiliares no controle das parasitoses, entretanto, muitos produtos estão disponíveis no mercado e não têm comprovação científica de sua eficácia ou de possíveis efeitos colaterais. O objetivo deste estudo foi avaliar os efeitos hematológicos e hepáticos após a administração de torta de Neem (Azadirachta indica) em ovinos. Foram testadas três dosagens da torta de Neem adicionada ao sal mineral (1, 2 e 4%), administradas por 126 dias para 32 ovinos da raça Lacaune, divididos em quatro grupos sendo três grupos para os diferentes tratamentos e um controle, o qual recebeu somente sal mineral. Amostras de sangue foram colhidas a cada 21 dias para realização do hemograma completo, dosagem de proteína plasmática total e fibrinogênio e avaliação da bioquímica clínica hepática. Nestas mesmas ocasiões, amostras de fezes foram coletadas para a quantificação de ovos por grama de fezes (OPG). Foram observadas diferenças estatísticas entre momentos e grupos para diversas variáveis, porém sem estarem relacionadas à administração de torta de Neem. Os resultados obtidos de hemograma completo, dosagem de proteína plasmática total, fibrinogênio e de bioquímica clínica hepática indica


Due to high levels of parasite resistance to different commercial active ingredients, new control alternatives are being studied, including the phytotherapy. These measures aim to search for auxiliary methods in the control of parasitic diseases. However, there are many products available in the market and there are no scientific proof of its efficacy. The objective of this study was to evaluate the hematological and hepatic effects following administration of Neem pie (Azadirachta indica) in sheep. Three concentrations of Neem cake was added to the mineral salt (1, 2 and 4 %) and administered during 126 days to 32 Lacaune breed sheeps, divided into four groups: three groups for different treatments and a and a control were tested, the ladder receiving only mineral salt. Blood samples were taken every 21 days to perform the complete blood count, serum total plasma protein and fibrinogen and liver biochemical evaluation. In those same times, fecal samples were collected for quantification of eggs per gram of feces (EPG). Statistical differences between times and groups for several variables were observed, but without being related to the administration of Neem pie. The results of complete blood count, measurement of total plasma protein, fibrinogen and hepatic clinical biochemistry indicated that administration of Neem pie at concentrations of 1, 2 and 4%, does not interfere in hematological values, or on the integrity and liver function Lacaune sheep breed.


Assuntos
Azadirachta/fisiologia , Ração Animal/análise , Testes Hematológicos , Testes de Função Hepática , Ovinos
19.
Rev. bras. ciênc. vet ; 27(3): 137-145, jul./set. 2020. il.
Artigo em Português | LILACS, VETINDEX | ID: biblio-1373061

RESUMO

Devido aos altos índices de resistência dos parasitas aos diferentes princípios ativos comerciais, novas alternativas de controle vêm sendo estudadas, entre elas a fitoterapia. Essas medidas visam a busca de métodos auxiliares no controle das parasitoses, entretanto, muitos produtos estão disponíveis no mercado e não têm comprovação científica de sua eficácia ou de possíveis efeitos colaterais. O objetivo deste estudo foi avaliar os efeitos hematológicos e hepáticos após a administração de torta de Neem (Azadirachta indica) em ovinos. Foram testadas três dosagens da torta de Neem adicionada ao sal mineral (1, 2 e 4%), administradas por 126 dias para 32 ovinos da raça Lacaune, divididos em quatro grupos sendo três grupos para os diferentes tratamentos e um controle, o qual recebeu somente sal mineral. Amostras de sangue foram colhidas a cada 21 dias para realização do hemograma completo, dosagem de proteína plasmática total e fibrinogênio e avaliação da bioquímica clínica hepática. Nestas mesmas ocasiões, amostras de fezes foram coletadas para a quantificação de ovos por grama de fezes (OPG). Foram observadas diferenças estatísticas entre momentos e grupos para diversas variáveis, porém sem estarem relacionadas à administração de torta de Neem. Os resultados obtidos de hemograma completo, dosagem de proteína plasmática total, fibrinogênio e de bioquímica clínica hepática indicaram que a administração de torta de Neem nas concentrações de 1, 2 e 4%, não interfere nos valores hematológicos, nem sobre a integridade e função hepática de ovinos da raça Lacaune.


Due to high levels of parasite resistance to different commercial active ingredients, new control alternatives are being studied, including the phytotherapy. These measures aim to search for auxiliary methods in the control of parasitic diseases. However, there are many products available in the market and there are no scientific proof of its efficacy. The objective of this study was to evaluate the hematological and hepatic effects following administration of Neem pie (Azadirachta indica) in sheep. Three concentrations of Neem cake was added to the mineral salt (1, 2 and 4%) and administered during 126 days to 32 Lacaune breed sheeps, divided into four groups: three groups for different treatments and a and a control were tested, the ladder receiving only mineral salt. Blood samples were taken every 21 days to perform the complete blood count, serum total plasma protein and fibrinogen and liver biochemical evaluation. In those same times, fecal samples were collected for quantification of eggs per gram of feces (EPG). Statistical differences between times and groups for several variables were observed, but without being related to the administration of Neem pie. The results of complete blood count, measurement of total plasma protein, fibrinogen and hepatic clinical biochemistry indicated that administration of Neem pie at concentrations of 1, 2 and 4%, does not interfere in hematological values, or on the integrity and liver function Lacaune sheep breed.


Assuntos
Animais , Contagem de Ovos de Parasitas/veterinária , Contagem de Células Sanguíneas/veterinária , Ovinos/sangue , Proteínas Sanguíneas/análise , Medicamento Fitoterápico , Testes Hematológicos/veterinária , Testes de Função Hepática/veterinária , Antiparasitários/uso terapêutico
20.
Angew Chem Int Ed Engl ; 59(38): 16795-16800, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32529715

RESUMO

A novel alkynyl phosphane gold(I) complex (trimethylphosphane)(3-(1,3-dimethylxanthine-7-yl)prop-1-yn-1-yl)gold(I) 1 displayed mutiple biological activites including selective proliferation inhibitory, anti-metastatic, and anti-angiogenic effects. The complex also induced effects related to aneuploidy in HCT-116 colon carcinoma cells, which might be mainly ascribed to the dysfunction of mitochondrial bioenergetics and downregulation of glycolysis. Induction of aneuploidy beyond a critical level can provide an effective strategy to target cancer, in particular colorectal tumours with a low tolerance of aneuploidy, and could be of relevance for 1 and other metallodrugs.


Assuntos
Aneuploidia , Antineoplásicos/farmacologia , Neoplasias do Colo/tratamento farmacológico , Compostos Organoáuricos/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Galinhas , Membrana Corioalantoide/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HCT116 , Humanos , Estrutura Molecular , Compostos Organoáuricos/síntese química , Compostos Organoáuricos/química , Óvulo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA