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1.
Med Res Rev ; 39(3): 887-909, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30421440

RESUMO

Survivin is a small protein that belongs to the inhibitor of apoptosis protein family. It is abundantly expressed in tumors compared with adult differentiated tissues, being associated with poor prognosis in many human neoplasms. This apoptotic inhibitor has a relevant role in both the promotion of cancer cell survival and in the inhibition of cell death. Consequently, aberrant survivin expression stimulates tumor progression and confers resistance to several therapeutic strategies in a variety of tumors. In fact, efficient survivin downregulation or inhibition results in spontaneous apoptosis or sensitization to chemotherapy and radiotherapy. Therefore, all these features make survivin an attractive therapeutic target to treat cancer. Currently, there are several survivin inhibitors under clinical evaluation, although more specific and efficient survivin inhibitors are being developed. Moreover, novel combination regimens targeting survivin together with other therapeutic approaches are currently being designed and assessed. In this review, recent progress in the therapeutic options targeting survivin for cancer treatment is analyzed. Direct survivin inhibitors and their current development status are explored. Besides, the major signaling pathways implicated in survivin regulation are described and different therapeutic approaches involving survivin indirect inhibition are evaluated. Finally, promising novel inhibitors under preclinical or clinical evaluation as well as challenges of developing survivin inhibitors as a new therapy for cancer treatment are discussed.


Assuntos
Terapia de Alvo Molecular , Neoplasias/terapia , Survivina/antagonistas & inibidores , Antineoplásicos/química , Antineoplásicos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Humanos , Transdução de Sinais/efeitos dos fármacos , Survivina/química , Survivina/metabolismo
2.
J Cell Physiol ; 234(3): 3105-3118, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30144392

RESUMO

The serine/threonine protein phosphatase 1 (PP1) inhibitors PPP1R2, PPP1R7, and PPP1R11 are evolutionarily ancient and highly conserved proteins. Four PP1 isoforms, PP1α, PP1ß, PP1γ1, and PP1γ2, exist; three of them except PP1γ2 are ubiquitous. The fact that PP1γ2 isoform is present only in mammalian testis and sperm led to the notion that isoform-specific regulators for PP1γ2 in sperm may be responsible for its function. In this report, we studied these inhibitors, PPP1R2, R7, and R11, to determine their spatial and temporal expression in testis and their regulatory functions in sperm. We show that, similar to PP1γ2, the three inhibitors are expressed at high levels in developing spermatogenic cells. However, the transcripts for the regulators are expressed as unique sizes in testis compared with somatic tissues. The three regulators share localization with PP1γ2 in the head and the principal piece of sperm. We show that the association of inhibitors to PP1γ2 changes during epididymal sperm maturation. In immotile caput epididymal sperm, PPP1R2 and PPP1R7 are not bound to PP1γ2, whereas in motile caudal sperm, all three inhibitors are bound as heterodimers or heterotrimers. In caudal sperm from male mice lacking sAC and glycogen synthase kinase 3, where motility and fertility are impaired, the association of PP1γ2 to the inhibitors resembles immature caput sperm. Changes in the association of the regulators with PP1γ2, due to their phosphorylation, are part of biochemical mechanisms responsible for the development of motility and fertilizing ability of sperm during their passage through the epididymis.


Assuntos
Proteína Fosfatase 1/genética , Proteínas/genética , Maturação do Esperma/genética , Espermatogênese/genética , Ubiquitina-Proteína Ligases/genética , Animais , Epididimo/crescimento & desenvolvimento , Epididimo/metabolismo , Humanos , Masculino , Camundongos , Fosforilação/efeitos dos fármacos , Motilidade dos Espermatozoides/genética , Espermatozoides/crescimento & desenvolvimento , Testículo/crescimento & desenvolvimento
3.
Inorg Chem ; 57(7): 4009-4022, 2018 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-29543468

RESUMO

The development of photoactivatable metal complexes with potential anticancer properties is a topical area of current investigation. Photoactivated chemotherapy using coordination compounds is typically based on photochemical processes occurring at the metal center. In the present study, an innovative approach is applied that takes advantage of the remarkable photochemical properties of diarylethenes. Following a proof-of-concept study with two complexes, namely, C1 and C2, a series of additional platinum(II) complexes from dithienylcyclopentene-based ligands was designed and prepared. Like C1 and C2, these new coordination compounds exhibit two thermally stable, interconvertible photoisomers that display distinct properties. The photochemical behavior of ligands L3-L7 has been analyzed by 1H NMR and UV-vis spectroscopies. Subsequently, the corresponding platinum(II) complexes C3-C7 were synthesized and fully characterized, including by single-crystal X-ray diffraction for some of them. Next, the interaction of each photoisomer (i.e., containing the open or closed ligand) of the metal complexes with DNA was examined thoroughly using various techniques, revealing their distinct DNA-binding modes and affinities, as observed for the earlier compounds C1 and C2. The antiproliferative activity of the two forms of the complexes was then assessed with five cancer cell lines and compared with that of C1 and C2, which supported the use of such diarylethene-based systems for the generation of a new class of potential photochemotherapeutic metallodrugs.


Assuntos
Complexos de Coordenação/farmacologia , DNA Super-Helicoidal/química , Compostos Organoplatínicos/farmacologia , Platina/química , Linhagem Celular Tumoral , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Complexos de Coordenação/efeitos da radiação , Ciclização , Fluorescência , Humanos , Substâncias Intercalantes/síntese química , Substâncias Intercalantes/química , Substâncias Intercalantes/farmacologia , Substâncias Intercalantes/efeitos da radiação , Isomerismo , Ligantes , Compostos Organoplatínicos/síntese química , Compostos Organoplatínicos/química , Compostos Organoplatínicos/efeitos da radiação
4.
Inorg Chem ; 57(23): 14786-14797, 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30444630

RESUMO

In the present study, the potential anti-neoplastic properties of a series of ruthenium half-sandwich complexes of formula [Ru(η6-arene)Cl2(PR1R2(1-pyrenyl))] (η6-arene = p-cymene and R1 = R2 = methyl for 1; η6-arene = methylbenzoate and R1 = R2 = methyl for 2; η6-arene = p-cymene and R1 = R2 = phenyl for 3; η6-arene = methylbenzoate and R1 = R2 = phenyl for 4; η6-arene = p-cymene, R1 = methyl and R2 = phenyl for 5; η6-arene = methylbenzoate, R1 = methyl and R2 = phenyl for 6) have been investigated. The six structurally related organoruthenium(II) compounds have been prepared in good yields and fully characterized; the X-ray structures of three of them, i.e., 1, 2, and 4, were determined. Although the piano-stool compounds contain a large polycyclic aromatic moiety, viz. a 1-pyrenyl group, they do not appear to interact with DNA. However, all the piano-stool complexes show significant cytotoxic properties against five human cell lines, namely, lung adenocarcinoma (A549), melanoma (A375), colorectal adenocarcinoma (SW620), breast adenocarcinoma (MCF7), and nontumorigenic epithelial breast (MCF10A), with IC50 values in the micromolar range for most of them. In addition, the most active compound, i.e., 2, induces a remarkable decrease of cell viability, that is in the nanomolar range, against two human neuroblastoma cell lines, namely, SK-N-BE(2) and CHLA-90. Complexes 1-6 are all capable of inducing apoptosis, but with various degrees of magnitude. Whereas 1, 3, 5, and 6 have no effect on the cell cycle of A375 cells, 2 and 4 can arrest it at the G2/M phase; furthermore, 2 (which is the most efficient compound of the series) also stops the cycle at the S phase, behaving as the well-known anticancer agent cisplatin. Finally, 2 is able to inhibit/reduce the cell migration of neuroblastoma SK-N-BE(2) cells.


Assuntos
Antineoplásicos/farmacologia , Benzoatos/farmacologia , Complexos de Coordenação/farmacologia , Monoterpenos/farmacologia , Neuroblastoma/patologia , Rutênio/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Benzoatos/química , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Cristalografia por Raios X , Cimenos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Ligantes , Modelos Moleculares , Estrutura Molecular , Monoterpenos/química , Rutênio/química
5.
Inorg Chem ; 55(11): 5356-64, 2016 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-27152916

RESUMO

A diplatinum(II) complex was prepared from a new 1,2-dithienylethene-based ligand containing N-methylimidazole groups as metal-binding units. Reaction of the ligand 1,2-bis[2-methyl-5-(1-methyl-1H-imidazol-2-yl)-3-thienyl]-cyclopentene (L2(H)) with cis-dichlorobis(dimethylsulfoxido)platinum(II) generated the bimetallic complex trans-[Pt2Cl4(DMSO)2(L2(H))] (DMSO = dimethyl sulfoxide), whose DNA-interacting properties were investigated using different techniques. Cytotoxicity assays with various cancer cell lines showed that this compound is active, with IC50 values in the micromolar range. Surprisingly, the diplatinum(II) complex does not exhibit the anticipated photoswitching properties; indeed, UV irradiation does not lead to the photocyclization of the ligand L2(H) or of the metal complex. Computational studies were performed and revealed significant differences in the electronic structure of L2(H) compared with L1(H) (i.e., 1,2-bis[2-methyl-5-(4-pyridyl)-3-thienyl]-cyclopentene, which exhibits photoswitching properties), in terms of the relevant molecular orbitals involved in the UV-vis absorption features, which ultimately is responsible for the inertia of L2(H) toward photocyclization.

6.
Reprod Fertil Dev ; 28(7): 1009-1019, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25562328

RESUMO

Phosphoprotein phosphatase 1 (PPP1) catalytic subunit gamma 2 (PPP1CC2), a PPP1 isoform, is largely restricted to testicular germ cells and spermatozoa. The key to understanding PPP1 regulation in male germ cells lies in the identification and characterisation of its interacting partners. This study was undertaken to determine the expression patterns of the several ankyrin repeat protein variant 2 (SARP2), a PPP1-interacting protein, in testis and spermatozoa. SARP2 was found to be highly expressed in testis and spermatozoa, and its interaction with human spermatozoa endogenous PPP1CC2 was confirmed by immunoprecipitation. Expression analysis by RT-qPCR revealed that SARP2 and PPP1CC2 mRNA levels were significantly higher in the spermatocyte fraction. However, microscopy revealed that SARP2 protein was only present in the nucleus of elongating and mature spermatids and in spermatozoa. In spermatozoa, SARP2 was prominently expressed in the connecting piece and flagellum, as well as, to a lesser extent, in the acrosome. A yeast two-hybrid approach was used to detect SARP2-interacting proteins and a relevant interaction with a novel sperm-associated antigen 9 (SPAG9) variant, a testis and spermatozoa-specific c-Jun N-terminal kinase-binding protein, was validated in human spermatozoa. Given the expression pattern of SARP2 and its association with PPP1CC2 and SPAG9, it may play a role in spermiogenesis and sperm function, namely in sperm motility and the acrosome reaction.


Assuntos
Repetição de Anquirina , Proteína Fosfatase 1/fisiologia , Espermatozoides/fisiologia , Testículo/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Humanos , Masculino , Motilidade dos Espermatozoides , Espermatogênese
7.
Angew Chem Int Ed Engl ; 54(15): 4561-5, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25689285

RESUMO

The photoactivation of potential anticancer metal complexes is a hot topic of current research as it may lead to the development of more selective drugs. Photoactivated chemotherapy (PACT) with coordination compounds is usually based on a (photo)chemical reaction taking place at the metal center. Herein, a new strategy is exploited that consists of "photomodifying" a ligand coordinated to metal ions. Platinum(II) complexes from photoswitchable 1,2-dithienylethene-containing ligands have been prepared, which exhibit two interconvertible photoisomeric forms that present distinct DNA-interacting properties and cytotoxic behaviors.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Compostos Organoplatínicos/química , Compostos Organoplatínicos/farmacologia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Linhagem Celular Tumoral , DNA/metabolismo , Desenho de Fármacos , Humanos , Modelos Moleculares , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo
8.
J Cell Mol Med ; 18(4): 555-67, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24629090

RESUMO

Protein phosphorylation is a key mechanism by which normal and cancer cells regulate their main transduction pathways. Protein kinases and phosphatases are precisely orchestrated to achieve the (de)phosphorylation of candidate proteins. Indeed, cellular health is dependent on the fine-tune of phosphorylation systems, which when deregulated lead to cancer. Transforming growth factor beta (TGF-ß) pathway involvement in the genesis of prostate cancer has long been established. Many of its members were shown to be hypo- or hyperphosphorylated during the process of malignancy. A major phosphatase that is responsible for the vast majority of the serine/threonine dephosphorylation is the phosphoprotein phosphatase 1 (PPP1). PPP1 has been associated with the dephosphorylation of several proteins involved in the TGF-ß cascade. This review will discuss the role of PPP1 in the regulation of several TGF-ß signalling members and how the subversion of this pathway is related to prostate cancer development. Furthermore, current challenges on the protein phosphatases field as new targets to cancer therapy will be addressed.


Assuntos
Carcinogênese/genética , Neoplasias da Próstata/genética , Proteína Fosfatase 1/metabolismo , Fator de Crescimento Transformador beta/genética , Matriz Extracelular/metabolismo , Fatores de Diferenciação de Crescimento/genética , Humanos , Masculino , Fosforilação , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Transdução de Sinais/genética , Fator de Crescimento Transformador beta/metabolismo
9.
BMC Evol Biol ; 13: 242, 2013 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-24195737

RESUMO

BACKGROUND: Pseudogenes are traditionally considered "dead" genes, therefore lacking biological functions. This view has however been challenged during the last decade. This is the case of the Protein phosphatase 1 regulatory subunit 2 (PPP1R2) or inhibitor-2 gene family, for which several incomplete copies exist scattered throughout the genome. RESULTS: In this study, the pseudogenization process of PPP1R2 was analyzed. Ten PPP1R2-related pseudogenes (PPP1R2P1-P10), highly similar to PPP1R2, were retrieved from the human genome assembly present in the databases. The phylogenetic analysis of mammalian PPP1R2 and related pseudogenes suggested that PPP1R2P7 and PPP1R2P9 retroposons appeared before the great mammalian radiation, while the remaining pseudogenes are primate-specific and retroposed at different times during Primate evolution. Although considered inactive, four of these pseudogenes seem to be transcribed and possibly possess biological functions. Given the role of PPP1R2 in sperm motility, the presence of these proteins was assessed in human sperm, and two PPP1R2-related proteins were detected, PPP1R2P3 and PPP1R2P9. Signatures of negative and positive selection were also detected in PPP1R2P9, further suggesting a role as a functional protein. CONCLUSIONS: The results show that contrary to initial observations PPP1R2-related pseudogenes are not simple bystanders of the evolutionary process but may rather be at the origin of genes with novel functions.


Assuntos
Evolução Molecular , Genoma Humano , Filogenia , Proteína Fosfatase 1/genética , Pseudogenes , Animais , Genoma , Humanos , Masculino , Mamíferos/genética , Retroelementos , Motilidade dos Espermatozoides
10.
BMC Cell Biol ; 14: 15, 2013 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-23506001

RESUMO

BACKGROUND: Protein Ser/Thr Phosphatase PPP1CC2 is an alternatively spliced isoform of PPP1C that is highly enriched in testis and selectively expressed in sperm. Addition of the phosphatase inhibitor toxins okadaic acid or calyculin A to caput and caudal sperm triggers and stimulates motility, respectively. Thus, the endogenous mechanisms of phosphatase inhibition are fundamental for controlling sperm function and should be characterized. Preliminary results have shown a protein phosphatase inhibitor activity resembling PPP1R2 in bovine and primate spermatozoa. RESULTS: Here we show conclusively, for the first time, that PPP1R2 is present in sperm. In addition, we have also identified a novel protein, PPP1R2P3. The latter was previously thought to be an intron-less pseudogene. We show that the protein corresponding to the pseudogene is expressed. It has PPP1 inhibitory potency similar to PPP1R2. The potential phosphosites in PPP1R2 are substituted by non-phosphorylable residues, T73P and S87R, in PPP1R2P3. We also confirm that PPP1R2/PPP1R2P3 are phosphorylated at Ser121 and Ser122, and report a novel phosphorylation site, Ser127. Subfractionation of sperm structures show that PPP1CC2, PPP1R2/PPP1R2P3 are located in the head and tail structures. CONCLUSIONS: The conclusive identification and localization of sperm PPP1R2 and PPP1R2P3 lays the basis for future studies on their roles in acrosome reaction, sperm motility and hyperactivation. An intriguing possibility is that a switch in PPP1CC2 inhibitory subunits could be the trigger for sperm motility in the epididymis and/or sperm hyperactivation in the female reproductive tract.


Assuntos
Proteínas/metabolismo , Espermatozoides/metabolismo , Sequência de Aminoácidos , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Masculino , Dados de Sequência Molecular , Fosforilação , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteína Fosfatase 1/antagonistas & inibidores , Proteína Fosfatase 1/metabolismo , Proteínas/química , Proteínas/genética , Alinhamento de Sequência , Motilidade dos Espermatozoides , Testículo/metabolismo
11.
Mol Hum Reprod ; 17(8): 466-77, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21257602

RESUMO

Infertility is a growing concern in modern society, with 30% of cases being due to male factors, namely reduced sperm concentration, decreased motility and abnormal morphology. Sperm cells are highly compartmentalized, almost devoid of transcription and translation consequently processes such as protein phosphorylation provide a key general mechanism for regulating vital cellular functions, more so than for undifferentiated cells. Reversible protein phosphorylation is the principal mechanism regulating most physiological processes in eukaryotic cells. To date, hundreds of protein kinases have been identified, but significantly fewer phosphatases (PPs) are responsible for counteracting their action. This discrepancy can be explained in part by the mechanism used to control phosphatase activity, which is based on regulatory interacting proteins. This is particularly true for PP1, a major serine/threonine-PP, for which >200 interactors (PP1 interacting proteins-PIPs) have been indentified that control its activity, subcellular location and substrate specificity. For PP1, several isoforms have been described, among them PP1γ2, a testis/sperm-enriched PP1 isoform. Recent findings support our hypothesis that PP1γ2 is involved in the regulation of sperm motility. This review summarizes the known sperm-specific PP1-PIPs, involved in the acquisition of mammalian sperm motility. The complexes that PP1 routinely forms with different proteins are addressed and the role of PP1/A-kinase anchoring protein complexes in sperm motility is considered. Furthermore, the potential relevance of targeting PP1-PIPs complexes to infertility diagnostics and therapeutics as well as to male contraception is also discussed.


Assuntos
Proteínas de Ancoragem à Quinase A/metabolismo , Proteína Fosfatase 1/metabolismo , Motilidade dos Espermatozoides/fisiologia , Animais , Anticoncepção , Humanos , Infertilidade Masculina , Masculino , Fosforilação , Isoformas de Proteínas , Proteína Fosfatase 1/genética , Transdução de Sinais
12.
Kidney Int Rep ; 6(3): 636-644, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33732978

RESUMO

INTRODUCTION: Acute kidney injury (AKI) is associated with increased health care utilization and higher costs. The Tackling AKI study was a multicenter, pragmatic, stepped-wedge cluster randomized trial that demonstrated a reduced hospital length of stay after implementation of a multifaceted AKI intervention (e-alerts, care bundle, and an education program). We tested whether this would result in cost savings. METHODS: A decision-analytic tree model from the payer perspective (National Health Service in the United Kingdom) was generated on which cost-effectiveness analyses were performed using a probabilistic sensitivity analysis, accounting only for direct medical costs. Clinical data from the Tackling AKI study were used as inputs and economic and utility data derived from relevant published literature. RESULTS: A total of 24,059 AKI episodes occurred during the study period, and in 18,887 admissions the patient was discharged alive. When all AKI stages were considered together, the cost per AKI admission was £5065 in the control arm and £4333 in the intervention arm, representing an incremental cost saving of £732 per admission with the intervention. Similar results were obtained when AKI stages were included as separate variables. Costs per quality-adjusted life year were £61,194 in the control group and £51,161 in the intervention group. At a willingness to pay threshold of £20,000 per quality-adjusted life year, the probability of the intervention being cost-effective compared with standard care was 90%. CONCLUSION: An organizational level approach to improve standards of AKI care reduces the cost of hospital admissions and is cost effective within the National Health Service in the United Kingdom.

13.
J Inorg Biochem ; 198: 110749, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31200320

RESUMO

Three Pt(II) complexes containing the natural ligands curcumin and caffeine, namely [Pt(curc)(PPh3)2]Cl (1), [PtCl(curc)(DMSO)] (2) (curc = deprotonated curcumin) and trans-[Pt(caffeine)Cl2(DMSO)] (3), were synthesized and fully characterized. The data obtained suggest that, for both 1 and 2, the anion of curcumin is coordinated to the platinum ion via the oxygen atoms of the ß-diketonate moiety. Spectroscopic features reveal that in 2 and 3, a DMSO molecule is S-bonded to the metal centre. For 3, all data indicate a square-planar geometry formed by a 9-N bonded caffeine, two trans chloride anions and a DMSO. The three complexes undergo changes in solution upon incubation for 24 h; 1 and 2 release curcumin while 3 isomerizes from trans to cis configuration. The DNA-binding and cytotoxic properties of 1-3 were evaluated in vitro. Despite their structural similarity, curcuminate-containing 1 and 2 exhibit distinct DNA interactions. While 1 appears to intercalate between nucleobase pairs, inducing the oxidative degradation of the biomolecule, 2 behaves as a groove binder, by means of electrostatic forces. Caffeine-containing 3 exhibits a behaviour that is comparable to that of 2. Complexes 1 and 2 showed moderate to high cytotoxicity and selectivity against several cancer cell lines, while 3 is inactive. Compounds 1 and 2 can be further activated by visible-light irradiation.


Assuntos
Antineoplásicos/farmacologia , Cafeína/farmacologia , Complexos de Coordenação/farmacologia , Curcumina/farmacologia , DNA/metabolismo , Animais , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Cafeína/análogos & derivados , Cafeína/síntese química , Cafeína/metabolismo , Bovinos , Linhagem Celular Tumoral , Cisplatino/farmacologia , Complexos de Coordenação/síntese química , Complexos de Coordenação/metabolismo , Curcumina/análogos & derivados , Curcumina/síntese química , Curcumina/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Estabilidade de Medicamentos , Humanos , Ligantes , Estrutura Molecular , Platina/química
14.
Biomolecules ; 9(8)2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31412593

RESUMO

Lung cancer is the leading cause of cancer-related deaths worldwide; hence novel treatments for this malignancy are eagerly needed. Since natural-based compounds represent a rich source of novel chemical entities in drug discovery, we have focused our attention on tambjamines, natural compounds isolated from marine invertebrates that have shown diverse pharmacological activities. Based on these structures, we have recently identified the novel indole-based tambjamine analog 21 (T21) as a promising antitumor agent, which modulates the expression of apoptotic proteins such as survivin. This antiapoptotic protein plays an important role in carcinogenesis and chemoresistance. In this work, we have elucidated the molecular mechanism by which the anticancer compound T21 exerts survivin inhibition and have validated this protein as a therapeutic target in different lung cancer models. T21 was able to reduce survivin protein levels in vitro by repressing its gene expression through the blockade of Janus kinase/Signal Transducer and Activator of Transcription-3 (JAK/STAT3)/survivin signaling pathway. Interestingly, this occurred even when the pathway was overstimulated with its ligand interleukin 6 (IL-6), which is frequently overexpressed in lung cancer patients who show poor clinical outcomes. Altogether, these results show T21 as a potent anticancer compound that effectively decreases survivin levels through STAT3 inhibition in lung cancer, appearing as a promising therapeutic drug for cancer treatment.


Assuntos
Antineoplásicos/farmacologia , Produtos Biológicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Proteína gp41 do Envelope de HIV/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Fragmentos de Peptídeos/farmacologia , Fator de Transcrição STAT3/antagonistas & inibidores , Survivina/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/química , Produtos Biológicos/síntese química , Produtos Biológicos/química , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Proteína gp41 do Envelope de HIV/síntese química , Proteína gp41 do Envelope de HIV/química , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Estrutura Molecular , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/química , Fator de Transcrição STAT3/metabolismo , Relação Estrutura-Atividade , Survivina/metabolismo
15.
Dalton Trans ; 47(22): 7551-7560, 2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-29790536

RESUMO

Novel tinidazole (tnz) coordination compounds of different geometries were synthesised, whose respective solid-state packing appears to be driven by inter- and intramolecular lone pairπ interactions. The copper(ii) compounds exhibit interesting redox properties originating from both the tnz and the metal ions. These complexes interact with DNA through two distinct ways, namely via electrostatic interactions or/and groove binding, and they can mediate the generation of ROS that damage the biomolecule. Cytotoxic studies revealed an interesting activity of the dinuclear compound [Cu(tnz)2(µ-Cl)Cl]27, which is further more efficient towards cancer cells, compared with normal cells.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , DNA/efeitos dos fármacos , Tinidazol/química , Células A549 , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cobalto/química , Complexos de Coordenação/síntese química , Cobre/química , DNA/química , Técnicas Eletroquímicas , Humanos , Células MCF-7 , Oxirredução , Zinco/química
16.
Dalton Trans ; 46(34): 11214-11222, 2017 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-28795757

RESUMO

Reaction of cis-[PtCl2(DMSO)2] with the ligand 4-methyl-2-N-(2-pyridylmethylene)aminophenol (Hpyrimol, LH) in methanol at room temperature produces the complexes [PtCl2LH] or [PtClL], under acidic or basic conditions, respectively. The two platinum compounds exhibit distinct DNA-interacting properties, [PtCl2LH] showing a higher affinity for the biomolecules. Furthermore, [PtClL] is clearly more cytotoxic than [PtCl2LH] in three different cancer cell lines. Solution studies reveal the occurrence of intricate solvation processes generating different aquated/hydroxido species, whose nature depends on the starting metal complex and the pH of the medium.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Compostos Organoplatínicos/química , Compostos Organoplatínicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio
17.
Biochem Pharmacol ; 126: 23-33, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27890727

RESUMO

Current pharmacological treatments for lung cancer show very poor clinical outcomes, therefore, the development of novel anticancer agents with innovative mechanisms of action is urgently needed. Cancer cells have a reversed pH gradient compared to normal cells, which favours cancer progression by promoting proliferation, metabolic adaptation and evasion of apoptosis. In this regard, the use of ionophores to modulate intracellular pH appears as a promising new therapeutic strategy. Indeed, there is a growing body of evidence supporting ionophores as novel antitumour drugs. Despite this, little is known about the implications of pH deregulation and homeostasis imbalance triggered by ionophores at the cellular level. In this work, we deeply analyse for the first time the anticancer effects of tambjamine analogues, a group of highly effective anion selective ionophores, at the cellular and molecular levels. First, their effects on cell viability were determined in several lung cancer cell lines and patient-derived cancer stem cells, demonstrating their potent cytotoxic effects. Then, we have characterized the induced lysosomal deacidification, as well as, the massive cytoplasmic vacuolization observed after treatment with these compounds, which is consistent with mitochondrial swelling. Finally, the activation of several proteins involved in stress response, autophagy and apoptosis was also detected, although they were not significantly responsible for the cell death induced. Altogether, these evidences suggest that tambjamine analogues provoke an imbalance in cellular ion homeostasis that triggers mitochondrial dysfunction and lysosomal deacidification leading to a potent cytotoxic effect through necrosis in lung cancer cell lines and cancer stem cells.


Assuntos
Alcaloides/farmacologia , Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Ionóforos/farmacologia , Lisossomos/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Pirróis/farmacologia , Alcaloides/síntese química , Antineoplásicos/síntese química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Concentração de Íons de Hidrogênio , Lisossomos/metabolismo , Mitocôndrias/patologia , Tamanho Mitocondrial , Necrose , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Pirróis/síntese química
18.
Toxicol Lett ; 280: 57-69, 2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28818578

RESUMO

The use of the chemotherapeutic drug doxorubicin (DOX) is limited by its toxicity in several organs such as testes. So, we analyzed the effect of endurance treadmill exercise training (EX) performed before sub-chronic DOX treatment on sperm count and motility, testes markers of oxidative damage and apoptosis. Tissue profiling of proteins more susceptible to oxidation was made to identify the molecular pathways regulated by oxidative modifications, as nitration and carbonylation. Twenty-four adult male rats were divided into four groups (n=6/group): sedentary saline (SED+SAL), sedentary sub-chronically injected with DOX (2mg-kg-1 per week, during 7 weeks; SED+DOX), 12 weeks trained saline (EX+SAL) and trained treated with DOX (EX+DOX). DOX treatment started 5 weeks after the beginning of the exercise program. Testes caspase-3, -8 and -9, as well as aconitase activities, the content of malondialdehyde (MDA), sulfhydryl groups (-SH), carbonyl and nitrotyrosine derivatives were determined. Modified proteins were identified by 2D-Western blot followed by MALDI-TOF/TOF mass spectrometry, and bioinformatic analysis was performed to assess the biological processes regulated by these chemical modifications. The decreased sperm motility induced by DOX was not modified by exercise. Significant increases in MDA content in SED+DOX and in caspase-3 and -9 activities in EX+DOX were found. Despite no significant differences in the levels of carbonylated and nitrated proteins, exercise modulated testis proteome susceptibility to oxidation in DOX-treated group, with less modified proteins identified. Zinc finger Ran-binding domain-containing protein 2 (ZRAB2) and AN1-type zinc finger protein 3 (ZFAN3) were among the proteins found oxidativelly modified. Although no marked alterations in testes oxidative damage were noticed, proteomic analysis of oxidativelly modified proteins highlighted the protective role of exercise against oxidative damage of some proteins involved in metabolism and stress response against DOX.


Assuntos
Doxorrubicina/toxicidade , Regulação da Expressão Gênica/efeitos dos fármacos , Condicionamento Físico Animal , Proteoma/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testículo/metabolismo , Animais , Antibióticos Antineoplásicos/toxicidade , Apoptose , Eletroforese em Gel Bidimensional , Masculino , Estresse Oxidativo , Distribuição Aleatória , Ratos , Espectrometria de Massas em Tandem , Transcriptoma/efeitos dos fármacos
19.
Mol Cancer Ther ; 16(7): 1224-1235, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28396364

RESUMO

Lung cancer has become the leading killer cancer worldwide, due to late diagnosis and lack of efficient anticancer drugs. We have recently described novel natural-derived tambjamine analogues that are potent anion transporters capable of disrupting cellular ion balance, inducing acidification of the cytosol and hyperpolarization of cellular plasma membranes. Although these tambjamine analogues were able to compromise cell survival, their molecular mechanism of action remains largely unknown. Herein we characterize the molecular cell responses induced by highly active indole-based tambjamine analogues treatment in lung cancer cells. Expression changes produced after compounds treatment comprised genes related to apoptosis, cell cycle, growth factors and its receptors, protein kinases and topoisomerases, among others. Dysregulation of BCL2 and BIRC5/survivin genes suggested the apoptotic pathway as the induced molecular cell death mechanism. In fact, activation of several proapoptotic markers (caspase-9, caspase-3, and PARP) and reversion of the cytotoxic effect upon treatment with an apoptosis inhibitor (Z-VAD-FMK) were observed. Moreover, members of the Bcl-2 protein family suffered changes after tambjamine analogues treatment, with a concomitant protein decrease towards the prosurvival members. Besides this, it was observed cellular accumulation of ROS upon compound treatment and an activation of the stress-kinase p38 MAPK route that, when inhibited, reverted the cytotoxic effect of the tambjamine analogues. Finally, a significant therapeutic effect of these compounds was observed in subcutaneous and orthotopic lung cancer mice models. Taken together, these results shed light on the mechanism of action of novel cytotoxic anionophores and demonstrate the therapeutic effects against lung cancer. Mol Cancer Ther; 16(7); 1224-35. ©2017 AACR.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Pirróis/administração & dosagem , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Animais , Ciclo Celular , Linhagem Celular Tumoral , Ativação Enzimática/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Indóis/administração & dosagem , Indóis/química , Proteínas Inibidoras de Apoptose/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Camundongos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Survivina , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Biochem Mol Biol Educ ; 44(3): 297-303, 2016 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-26891775

RESUMO

At the Portuguese universities, practical classes of life sciences are usually professor-centered 2-hour classes. This approach results in students underprepared for a real work environment in a research/clinical laboratory. To provide students with a real-life laboratory environment, the Non-Stop Lab Week (NSLW) was created in the Molecular Biomedicine master program at the University of Aveiro, Portugal. The unique feature of the NSLW is its intensity: during a 1-week period, students perform a subcloning and a protein expression project in an environment that mimics a real laboratory. Students work autonomously, and the progression of work depends on achieving the daily goals. Throughout the three curricular years, most students considered the intensity of the NSLW a very good experience and fundamental for their future. Moreover, after some experience in a real laboratory, students state that both the techniques and the environment created in the NSLW were similar to what they experience in their current work situation. The NSLW fulfills a gap in postgraduate students' learning, particularly in practical skills and scientific thinking. Furthermore, the NSLW experience provides skills to the students that are crucial to their future research area. © 2016 by The International Union of Biochemistry and Molecular Biology, 44:297-303, 2016.


Assuntos
Disciplinas das Ciências Biológicas/educação , Currículo , Educação Continuada/normas , Educação de Pós-Graduação/métodos , Laboratórios/normas , Humanos , Universidades
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