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1.
Life Sci ; 268: 118936, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33421523

RESUMO

AIMS: During oxidative stress mitochondria become the main source of endogenous reactive oxygen species (ROS) production. In the present study, we aimed to clarify the effects of pharmacological PARP-1 inhibition on mitochondrial function and quality control processes. MAIN METHODS: L-2286, a quinazoline-derivative PARP inhibitor, protects against cardiovascular remodeling and heart failure by favorable modulation of signaling routes. We examined the effects of PARP-1 inhibition on mitochondrial quality control processes and function in vivo and in vitro. Spontaneously hypertensive rats (SHRs) were treated with L-2286 or placebo. In the in vitro model, 150 µM H2O2 stress was applied on neonatal rat cardiomyocytes (NRCM). KEY FINDINGS: PARP-inhibition prevented the development of left ventricular hypertrophy in SHRs. The interfibrillar mitochondrial network were less fragmented, the average mitochondrial size was bigger and showed higher cristae density compared to untreated SHRs. Dynamin related protein 1 (Drp1) translocation and therefore the fission of mitochondria was inhibited by L-2286 treatment. Moreover, L-2286 treatment increased the amount of fusion proteins (Opa1, Mfn2), thus preserving structural stability. PARP-inhibition also preserved the mitochondrial genome integrity. In addition, the mitochondrial biogenesis was also enhanced due to L-2286 treatment, leading to an overall increase in the ATP production and improvement in survival of stressed cells. SIGNIFICANCE: Our results suggest that the modulation of mitochondrial dynamics and biogenesis can be a promising therapeutical target in hypertension-induced myocardial remodeling and heart failure.


Assuntos
Hipertensão/fisiopatologia , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Mitocôndrias Cardíacas/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Animais , Células Cultivadas , Citrato (si)-Sintase/metabolismo , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Eletrocardiografia , Glutationa/metabolismo , Hipertrofia Ventricular Esquerda/etiologia , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/patologia , Mitocôndrias Cardíacas/ultraestrutura , Proteínas Mitocondriais/metabolismo , Miócitos Cardíacos/patologia , Peptídeo Natriurético Encefálico/sangue , Piperidinas/farmacologia , Quinazolinas/farmacologia , Ratos Endogâmicos SHR , Ratos Wistar
2.
Cancer Immunol Immunother ; 70(3): 843-856, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33492447

RESUMO

Immune checkpoint inhibitors (ICIs) that target programmed cell death protein 1 (PD-1) and programmed death-ligand 1 (PD-L1) have shown modest activity as monotherapies for the treatment of ovarian cancer (OC). The rationale for using these therapies in combination with poly (ADP-ribose) polymerase inhibitors (PARP-Is) has been described, and their in vivo application will benefit from ex vivo platforms that aid in the prediction of patient response or resistance to therapy. This study examined the effectiveness of detecting patient-specific immune-related activity in OC using three-dimensional (3D) spheroids. Immune-related cell composition and PD-1/PD-L1 expression status were evaluated using cells dissociated from fresh OC tissue from two patients prior to and following 3D culture. The patient sample with the greatest increase in the proportion of PD-L1 + cells also possessed more activated cytotoxic T cells and mature DCs compared to the other patient sample. Upon cytokine stimulation, patient samples demonstrated increases in cytotoxic T cell activation and DC major histocompatibility complex (MHC) class-II expression. Pembrolizumab increased cytokine secretion, enhanced olaparib cytotoxicity, and reduced spheroid viability in a T cell-dependent manner. Furthermore, durvalumab and olaparib combination treatment increased cell death in a synergistic manner. This work demonstrates that immune cell activity and functional modulation can be accurately detected using our ex vivo 3D spheroid platform, and it presents evidence for their utility to demonstrate sensitivity to ICIs alone or in combination with PARP-Is in a preclinical setting.


Assuntos
Antineoplásicos/farmacologia , Antígeno B7-H1/antagonistas & inibidores , Ftalazinas/farmacologia , Piperazinas/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Linhagem Celular Tumoral , Células Cultivadas , Citocinas/metabolismo , Sinergismo Farmacológico , Humanos , Imunofenotipagem , Esferoides Celulares , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/metabolismo
3.
Gan To Kagaku Ryoho ; 48(1): 53-56, 2021 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-33468723

RESUMO

In 2018, olaparib, a PARP inhibitor, was approved for the treatment of BRCA1/2 gene-mutation positive and HER2-negative inoperable and recurrent breast cancer; BRCA1/2 gene testing was also listed as a companion diagnostics. Here, we identified microRNAs(miRNAs) expressed after treatment with olaparib, which differed in the presence or absence of BRCA1 mutations in triple negative breast cancer(TNBC), and examined the changes in miRNAs after exposure to the combination of the PARP-1 inhibitor and a chemotherapeutic agent. After exposure to the PARP-1 inhibitor, the expression of miR-141, miR-155, miR-205, and miR-223 decreased in MDA-MB-231, HCC1143, and BT549 cells and increased more than 10 times in MDA-MB-436 cells. Moreover, the expression of miR-141 in MDA-MB-436 cells treated with the PARP-1 inhibitor together with gemcitabine increased more than 10 times; additionally, the expression of miR-205 increased more in the context of combination therapy versus single exposure to olaparib. The miR-200 family(including miR-141)and miR- 205 are known to function as ZEB1/2 targets and to act as epithelial-to-mesenchymal transition(EMT)-suppressors. Overall, these results suggest that it may be possible to recover the sensitivity of TNBC cells to chemotherapy via the suppressing EMT through the use of a PARP-1 inhibitor in the context of BRCA1 mutation.


Assuntos
MicroRNAs , Neoplasias de Mama Triplo Negativas , Proteína BRCA1/genética , Linhagem Celular Tumoral , Humanos , MicroRNAs/genética , Mutação , Recidiva Local de Neoplasia , Ftalazinas , Piperazinas , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética
4.
Anticancer Res ; 41(2): 731-737, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33517277

RESUMO

BACKGROUND/AIM: FMS-like tyrosine kinase 3 (FLT3) is a class III receptor tyrosine kinase involved in signal transduction underlying survival, proliferation, and differentiation of hematopoietic cells. An internal tandem duplication (ITD) in FLT3 in the juxtamembrane domain is a common mutation causing human acute myeloid leukemia (AML) and activates constitutive signaling. MATERIALS AND METHODS: We evaluated the novel FLT3 inhibitor 5-(4-fluorophenyl)-N-(naphthalen-1-yl)oxazol-2-amine (AIU2008) for the treatment of AML. RESULTS: AIU2008 was designed by modifying FLT3 inhibitor 7c, and showed improved anti-leukemic efficacy in FLT3-ITD-positive AML cells. Specifically, AIU2008 inhibited cell growth and apoptotic death. In addition, AIU2008 down-regulated DNA repair genes involved in homologous recombination and non-homologous end joining. It contributed to the synergistic inhibition of AML cell growth in combination treatment with PARP inhibitors. CONCLUSION: AIU2008 is a promising FLT3 targeting agent, and may be used in combination with PARP inhibitors for the treatment of AML.


Assuntos
Antineoplásicos/farmacologia , Leucemia Mieloide Aguda/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Sequências de Repetição em Tandem , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dano ao DNA , Reparo do DNA/efeitos dos fármacos , Células HL-60 , Humanos , Leucemia Mieloide Aguda/enzimologia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/metabolismo
5.
mBio ; 12(1)2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33468703

RESUMO

By late 2020, the coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), had caused tens of millions of infections and over 1 million deaths worldwide. A protective vaccine and more effective therapeutics are urgently needed. We evaluated a new poly(ADP-ribose) polymerase (PARP) inhibitor, stenoparib, that recently advanced to phase II clinical trials for treatment of ovarian cancer, for activity against human respiratory coronaviruses, including SARS-CoV-2, in vitro Stenoparib exhibits dose-dependent suppression of SARS-CoV-2 multiplication and spread in Vero E6 monkey kidney and Calu-3 human lung adenocarcinoma cells. Stenoparib was also strongly inhibitory to the human seasonal respiratory coronavirus HCoV-NL63. Compared to remdesivir, which inhibits viral replication downstream of cell entry, stenoparib impedes entry and postentry processes, as determined by time-of-addition (TOA) experiments. Moreover, a 10 µM dosage of stenoparib-below the approximated 25.5 µM half-maximally effective concentration (EC50)-combined with 0.5 µM remdesivir suppressed coronavirus growth by more than 90%, indicating a potentially synergistic effect for this drug combination. Stenoparib as a stand-alone or as part of combinatorial therapy with remdesivir should be a valuable addition to the arsenal against COVID-19.IMPORTANCE New therapeutics are urgently needed in the fight against COVID-19. Repurposing drugs that are either already approved for human use or are in advanced stages of the approval process can facilitate more rapid advances toward this goal. The PARP inhibitor stenoparib may be such a drug, as it is currently in phase II clinical trials for the treatment of ovarian cancer and its safety and dosage in humans have already been established. Our results indicate that stenoparib possesses strong antiviral activity against SARS-CoV-2 and other coronaviruses in vitro. This activity appears to be based on multiple modes of action, where both pre-entry and postentry viral replication processes are impeded. This may provide a therapeutic advantage over many current options that have a narrower target range. Moreover, our results suggest that stenoparib and remdesivir in combination may be especially potent against coronavirus infection.


Assuntos
Antivirais/farmacologia , Coronavirus Humano NL63/efeitos dos fármacos , Isoquinolinas/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo , Quinazolinonas/farmacologia , Replicação Viral/efeitos dos fármacos , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/farmacologia , Alanina/análogos & derivados , Alanina/farmacologia , Animais , Antimetabólitos/farmacologia , Chlorocebus aethiops , Coronavirus Humano NL63/enzimologia , Reposicionamento de Medicamentos , Humanos , Células Vero
6.
Life Sci ; 267: 118975, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33387580

RESUMO

AIMS: Poly (ADP-ribose) polymerase- (PARP)-1 is predominantly triggered by DNA damage. Overexpression of PARP-1 is known for its association with the pathogenesis of several CNS disorders, such as Stroke, Parkinson's disease (PD), Alzheimer's disease (AD), Huntington (HD) and Amyotrophic lateral sclerosis (ALS). NAD+ depletion resulted PARP related cell death only happened when the trial used extreme high oxidization treatment. Inhibition of PARP1/2 may induce replication related cell death due to un-repaired DNA damage. This review has discussed PARP-1 modulated downstream pathways in neurodegeneration and various FDA approved PARP-1 inhibitors. MATERIALS AND METHODS: A systematic literature review of PubMed, Medline, Bentham, Scopus and EMBASE (Elsevier) databases was carried out to understand the nature of the extensive work done on mechanistic role of Poly (ADP-ribose) polymerase and its inhibition in Neurodegenerative diseases. KEY FINDINGS: Several researchers have put forward number of potential treatments, of which PARP-1 enzyme has been regarded as a potent target intended for the handling of neurodegenerative ailments. Targeting PARP using its chemical inhibitors in various neurodegenerative may have therapeutic outcomes by reducing neuronal death mediated by PARPi. Numerous PARP-1 inhibitors have been studied in neurodegenerative diseases but they haven't been clinically evaluated. SIGNIFICANCE: In this review, the pathological role of PARP-1 in various neurodegenerative diseases has been discussed along with the therapeutic role of PARP-1 inhibitors in various neurodegenerative diseases.


Assuntos
Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/enzimologia , Poli(ADP-Ribose) Polimerase-1/metabolismo , Animais , Doenças do Sistema Nervoso Central/tratamento farmacológico , Doenças do Sistema Nervoso Central/metabolismo , Humanos , Terapia de Alvo Molecular , Doenças Neurodegenerativas/metabolismo , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Poli(ADP-Ribose) Polimerase-1/genética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia
7.
Nat Cell Biol ; 23(2): 160-171, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33462394

RESUMO

The response to poly(ADP-ribose) polymerase inhibitors (PARPi) is dictated by homologous recombination (HR) DNA repair and the abundance of lesions that trap PARP enzymes. It remains unclear, however, if the established role of PARP in promoting chromatin accessibility impacts viability in these settings. Using a CRISPR-based screen, we identified the PAR-binding chromatin remodeller ALC1/CHD1L as a key determinant of PARPi toxicity in HR-deficient cells. ALC1 loss reduced viability of breast cancer gene (BRCA)-mutant cells and enhanced sensitivity to PARPi by up to 250-fold, while overcoming several resistance mechanisms. ALC1 deficiency reduced chromatin accessibility concomitant with a decrease in the association of base damage repair factors. This resulted in an accumulation of replication-associated DNA damage, increased PARP trapping and a reliance on HR. These findings establish PAR-dependent chromatin remodelling as a mechanistically distinct aspect of PARPi responses and therapeutic target in HR-deficient cancers.


Assuntos
Cromatina/metabolismo , DNA Helicases/metabolismo , Proteínas de Ligação a DNA/metabolismo , Recombinação Homóloga/genética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Proteína BRCA1/genética , Proteína BRCA2/genética , Sistemas CRISPR-Cas/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Aberrações Cromossômicas , DNA Helicases/química , Reparo do DNA/efeitos dos fármacos , Proteínas de Ligação a DNA/química , Epistasia Genética/efeitos dos fármacos , Instabilidade Genômica , Proteínas de Fluorescência Verde/metabolismo , Recombinação Homóloga/efeitos dos fármacos , Humanos , Metanossulfonato de Metila , Mutação/genética , Ftalazinas/farmacologia , Piperazinas/farmacologia , Poli Adenosina Difosfato Ribose/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Domínios Proteicos
8.
Mol Cell ; 81(4): 767-783.e11, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33333017

RESUMO

Chromatin is a barrier to efficient DNA repair, as it hinders access and processing of certain DNA lesions. ALC1/CHD1L is a nucleosome-remodeling enzyme that responds to DNA damage, but its precise function in DNA repair remains unknown. Here we report that loss of ALC1 confers sensitivity to PARP inhibitors, methyl-methanesulfonate, and uracil misincorporation, which reflects the need to remodel nucleosomes following base excision by DNA glycosylases but prior to handover to APEX1. Using CRISPR screens, we establish that ALC1 loss is synthetic lethal with homologous recombination deficiency (HRD), which we attribute to chromosome instability caused by unrepaired DNA gaps at replication forks. In the absence of ALC1 or APEX1, incomplete processing of BER intermediates results in post-replicative DNA gaps and a critical dependence on HR for repair. Hence, targeting ALC1 alone or as a PARP inhibitor sensitizer could be employed to augment existing therapeutic strategies for HRD cancers.


Assuntos
Montagem e Desmontagem da Cromatina , DNA Helicases/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Experimentais/metabolismo , Nucleossomos/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Animais , DNA Helicases/genética , Replicação do DNA/efeitos dos fármacos , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Proteínas de Ligação a DNA/genética , Recombinação Homóloga/efeitos dos fármacos , Camundongos , Camundongos Knockout , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Neoplasias Experimentais/genética , Nucleossomos/genética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Poli(ADP-Ribose) Polimerases/genética
9.
Biomed Pharmacother ; 133: 111041, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33378949

RESUMO

Poly (ADP-ribose) polymerase 1 (PARP1)-dependent cell death in the retinal pigment epithelium (RPE) is implicated in dry age-related macular degeneration (AMD). Although PARP1 inhibitors are available for treating dry AMD, their delivery route is not ideal for patients. The aim of this study was to test the efficacy of a novel PARP1-inhibitory compound (PIC) in vitro and in vivo. This study presents PIC, a novel small molecule, with superior efficacy to PARP1 inhibitors in the market. PIC demonstrated a distinctive inhibitory profile against PARP isotypes than the FDA-approved PARP1 inhibitors. PIC inhibited PARP1 activation at an IC50 of 0.41 ± 0.15 nM in an enzyme-based assay in vitro and at IC50 and EC50 in ARPE-19 cells of 0.11 ± 0.02 nM and 0.22 ± 0.02 nM, respectively, upon H2O2 insult. PIC also moderated mitochondrial fission and depolarization and maintained cellular energy levels under oxidative stress in ARPE-19 cells. Furthermore, PIC demonstrated good corneal penetration in a rat model, presenting PIC as a promising candidate for eye drop therapeutics for dry AMD. When PIC was administered as an eye drop formulation, RPE morphology was preserved, maintaining the thickness of the outer nuclear layers under sodium iodate (SI) treatment in rats. In SI-treated rabbits, eye drop administration of PIC also retained the structural and functional integrity when analyzed using funduscopy and electroretinogram. Collectively, our data portray PIC as an attractive treatment measure for dry AMD.


Assuntos
Degeneração Macular/tratamento farmacológico , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Epitélio Pigmentado da Retina/efeitos dos fármacos , Administração Oftálmica , Animais , Antioxidantes/farmacologia , Linhagem Celular , Modelos Animais de Doenças , Humanos , Iodatos , Degeneração Macular/induzido quimicamente , Degeneração Macular/enzimologia , Degeneração Macular/patologia , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Absorção Ocular , Soluções Oftálmicas , Estresse Oxidativo/efeitos dos fármacos , Poli(ADP-Ribose) Polimerase-1/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/administração & dosagem , Coelhos , Ratos Sprague-Dawley , Epitélio Pigmentado da Retina/enzimologia , Epitélio Pigmentado da Retina/patologia
10.
Biochim Biophys Acta Gen Subj ; 1865(1): 129760, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33035602

RESUMO

BACKGROUND: Cancer cells show highly increased glucose utilization which, among other cancer-essential functions, was found to facilitate DNA repair. Lactate dehydrogenase (LDH) activity is pivotal for supporting the high glycolytic flux of cancer cells; to our knowledge, a direct contribution of this enzyme in the control of DNA integrity was never investigated. In this paper, we looked into a possible LDH-mediated regulation of homologous recombination (HR) repair. METHODS: We identified two cancer cell lines with different assets in energy metabolism: either based on glycolytic ATP or on oxidative reactions. In cells with inhibited LDH, we assessed HR function by applying four different procedures. RESULTS: Our findings revealed an LDH-mediated control of HR, which was observed independently of cell metabolic asset. Since HR inhibition is known to make cancer cells responsive to PARP inhibitors, in both the cellular models we finally explored the effects of a combined inhibition of LDH and PARP. CONCLUSIONS: The obtained results suggest for LDH a central role in cancer cell biology, not merely linked to the control of energy metabolism. The involvement of LDH in the DNA damage response could suggest new drug combinations to obtain improved antineoplastic effects. GENERAL SIGNIFICANCE: Several evidences have correlated the metabolic features of cancer cells with drug resistance and LDH inhibition has been repeatedly shown to increase the antineoplastic power of chemotherapeutics. By shedding light on the processes linking cell metabolism to the control of DNA integrity, our findings also give a mechanistic explanation to these data.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , L-Lactato Desidrogenase/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Ftalazinas/farmacologia , Piperazinas/farmacologia , Reparo de DNA por Recombinação/efeitos dos fármacos , Linhagem Celular Tumoral , Glicólise/efeitos dos fármacos , Humanos , L-Lactato Desidrogenase/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia
11.
Int J Mol Sci ; 21(24)2020 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-33352723

RESUMO

Poly (ADP-ribose) polymerase inhibitor (PARPi, olaparib) impairs the repair of DNA single-strand breaks (SSBs), resulting in double-strand breaks (DSBs) that cannot be repaired efficiently in homologous recombination repair (HRR)-deficient cancers such as BRCA1/2-mutant cancers, leading to synthetic lethality. Despite the efficacy of olaparib in the treatment of BRCA1/2 deficient tumors, PARPi resistance is common. We hypothesized that the combination of olaparib with anticancer agents that disrupt HRR by targeting ataxia telangiectasia and Rad3-related protein (ATR) or checkpoint kinase 1 (CHK1) may be an effective strategy to reverse ovarian cancer resistance to olaparib. Here, we evaluated the effect of olaparib, the ATR inhibitor AZD6738, and the CHK1 inhibitor MK8776 alone and in combination on cell survival, colony formation, replication stress response (RSR) protein expression, DNA damage, and apoptotic changes in BRCA2 mutated (PEO-1) and HRR-proficient BRCA wild-type (SKOV-3 and OV-90) cells. Combined treatment caused the accumulation of DNA DSBs. PARP expression was associated with sensitivity to olaparib or inhibitors of RSR. Synergistic effects were weaker when olaparib was combined with CHK1i and occurred regardless of the BRCA2 status of tumor cells. Because PARPi increases the reliance on ATR/CHK1 for genome stability, the combination of PARPi with ATR inhibition suppressed ovarian cancer cell growth independently of the efficacy of HRR. The present results were obtained at sub-lethal doses, suggesting the potential of these inhibitors as monotherapy as well as in combination with olaparib.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Quinase 1 do Ponto de Checagem/antagonistas & inibidores , Cistadenocarcinoma Seroso/patologia , Recombinação Homóloga , Neoplasias Ovarianas/patologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Mutações Sintéticas Letais , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteína BRCA1/genética , Proteína BRCA2/genética , Quinase 1 do Ponto de Checagem/genética , Quinase 1 do Ponto de Checagem/metabolismo , Cistadenocarcinoma Seroso/tratamento farmacológico , Cistadenocarcinoma Seroso/genética , Feminino , Humanos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , RNA Interferente Pequeno/genética , Transdução de Sinais
12.
Molecules ; 25(24)2020 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-33352773

RESUMO

Theranostics are emerging as a pillar of cancer therapy that enable the use of single molecule constructs for diagnostic and therapeutic application. As poly adenosine diphosphate (ADP)-ribose polymerase 1 (PARP-1) is overexpressed in various cancer types, and is localized to the nucleus, PARP-1 can be safely targeted with Auger emitters to induce DNA damage in tumors. Here, we investigated a radioiodinated PARP inhibitor, [125I]KX1, and show drug target specific DNA damage and subsequent killing of BRCA1 and non-BRCA mutant ovarian cancer cells at sub-pharmacological concentrations several orders of magnitude lower than traditional PARP inhibitors. Furthermore, we demonstrated that viable tumor tissue from ovarian cancer patients can be used to screen tumor radiosensitivity ex-vivo, enabling the direct assessment of therapeutic efficacy. Finally, we showed tumors can be imaged by single-photon computed tomography (SPECT) with PARP theranostic, [123I]KX1, in a human ovarian cancer xenograft mouse model. These data support the utility of PARP-1 targeted radiopharmaceutical therapy as a theranostic option for PARP-1 overexpressing ovarian cancers.


Assuntos
Antineoplásicos/farmacologia , Proteína BRCA1/genética , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Poli(ADP-Ribose) Polimerase-1/genética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Animais , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/genética , Modelos Animais de Doenças , Feminino , Xenoenxertos , Humanos , Radioisótopos do Iodo/farmacologia , Camundongos SCID
13.
Int J Mol Sci ; 21(24)2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33339368

RESUMO

Small cell lung cancer (SCLC) is an aggressive type of lung cancer with high mortality that is caused by frequent relapses and acquired resistance. Despite that several target-based approaches with potential therapeutic impact on SCLC have been identified, numerous targeted drugs have not been successful in providing improvements in cancer patients when used as single agents. A combination of targeted therapies could be a strategy to induce maximum lethal effects on cancer cells. As a starting point in the development of new drug combination strategies for the treatment of SCLC, we performed a mid-throughput screening assay by treating a panel of SCLC cell lines with BETi or AKi in combination with PARPi or EZH2i. We observed drug synergy between I-BET762 and Talazoparib, BETi and PARPi, respectively, in SCLC cells. Combinatorial efficacy was observed in MYCs-amplified and MYCs-wt SCLC cells over SCLC cells with impaired MYC signaling pathway or non-tumor cells. We indicate that drug synergy between I-BET762 and Talazoparib is associated with the attenuation HR-DSBR process and the downregulation of various players of DNA damage response by BET inhibition, such as CHEK2, PTEN, NBN, and FANCC. Our results provide a rationale for the development of new combinatorial strategies for the treatment of SCLC.


Assuntos
Antineoplásicos/farmacologia , Benzodiazepinas/farmacologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , Ftalazinas/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Linhagem Celular Tumoral , Células Cultivadas , Dano ao DNA/efeitos dos fármacos , Sinergismo Farmacológico , Humanos
14.
Biosci Rep ; 40(10)2020 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-33063092

RESUMO

COVID-19 induces a proinflammatory environment that is stronger in patients requiring intensive care. The cytokine components of this environment may determine efficacy or otherwise of glucocorticoid therapy. The immunity modulators, the aryl hydrocarbon receptor (AhR) and the nuclear NAD+-consuming enzyme poly (ADP-ribose) polymerase 1 (PARP 1) may play a critical role in COVID-19 pathophysiology. The AhR is overexpressed in coronaviruses, including COVID-19 and, as it regulates PARP gene expression, the latter is likely to be activated in COVID-19. PARP 1 activation leads to cell death mainly by depletion of NAD+ and adenosine triphosphate (ATP), especially when availability of these energy mediators is compromised. PARP expression is enhanced in other lung conditions: the pneumovirus respiratory syncytial virus (RSV) and chronic obstructive pulmonary disease (COPD). I propose that PARP 1 activation is the terminal point in a sequence of events culminating in patient mortality and should be the focus of COVID-19 immunotherapy. Potent PARP 1 inhibitors are undergoing trials in cancer, but a readily available inhibitor, nicotinamide (NAM), which possesses a highly desirable biochemical and activity profile, merits exploration. It conserves NAD+ and prevents ATP depletion by PARP 1 and Sirtuin 1 (silent mating type information regulation 2 homologue 1) inhibition, enhances NAD+ synthesis, and hence that of NADP+ which is a stronger PARP inhibitor, reverses lung injury caused by ischaemia/reperfusion, inhibits proinflammatory cytokines and is effective against HIV infection. These properties qualify NAM for therapeutic use initially in conjunction with standard clinical care or combined with other agents, and subsequently as an adjunct to stronger PARP 1 inhibitors or other drugs.


Assuntos
Infecções por Coronavirus/tratamento farmacológico , Niacinamida/farmacologia , Pneumonia Viral/tratamento farmacológico , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Betacoronavirus/efeitos dos fármacos , Linhagem Celular , Infecções por Coronavirus/patologia , Citocinas/sangue , Humanos , Imunoterapia/métodos , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Cinurenina/metabolismo , Pandemias , Pneumonia Viral/patologia , Poli(ADP-Ribose) Polimerase-1/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo
15.
Life Sci ; 261: 118434, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32941897

RESUMO

Defective DNA repair is one of the most important features of tumors. BRCA1/2 participates in homologous recombination repair as a key tumor suppressor gene. BRCA1/2 mutation is an important biomarker for predicting the sensitivity of platinum salts and Poly (ADP-ribose) polymerase (PARP) inhibitors in breast cancer, ovarian cancer, and other cancers. However, epigenetic modifications and other mutations in homologous recombination repair (HRR) genes can also cause homologous recombination deficiency (HRD). Patients with no BRCA1/2 mutations, but bearing similar molecular phenotypes (BRCAness) can still obtain clinical benefits from treatment with platinum salts or PARP inhibitors. Therefore, an accurate assessment of HRD is essential for the formulation of personalized treatments. However, methods to identify HRD in tumors vary and are controversial. Currently, genomic scar assays have been used in multiple clinical trials to assess patient clinical benefit. This review summarizes the therapeutic effects of platinum salts and PARP inhibitors in breast and ovarian cancer, clarifies the predictive value of genomic scar assays in evaluating the clinical benefit of different patient groups and treatment options, and proposes the limitations and optimization of current HRD scoring methods. Using and optimizing genomic scar assays can help to accurately screen the population with the most benefit, expand the scope of drug application, and make the most suitable clinical decision based on individual differences.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/genética , Platina/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Animais , Antineoplásicos/farmacologia , Epigênese Genética/efeitos dos fármacos , Genômica , Humanos , Mutação/efeitos dos fármacos , Platina/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Reparo de DNA por Recombinação/efeitos dos fármacos
16.
Mol Cell ; 80(2): 327-344.e8, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32966758

RESUMO

Stabilization of stalled replication forks is a prominent mechanism of PARP (Poly(ADP-ribose) Polymerase) inhibitor (PARPi) resistance in BRCA-deficient tumors. Epigenetic mechanisms of replication fork stability are emerging but remain poorly understood. Here, we report the histone acetyltransferase PCAF (p300/CBP-associated) as a fork-associated protein that promotes fork degradation in BRCA-deficient cells by acetylating H4K8 at stalled replication forks, which recruits MRE11 and EXO1. A H4K8ac binding domain within MRE11/EXO1 is required for their recruitment to stalled forks. Low PCAF levels, which we identify in a subset of BRCA2-deficient tumors, stabilize stalled forks, resulting in PARPi resistance in BRCA-deficient cells. Furthermore, PCAF activity is tightly regulated by ATR (ataxia telangiectasia and Rad3-related), which phosphorylates PCAF on serine 264 (S264) to limit its association and activity at stalled forks. Our results reveal PCAF and histone acetylation as critical regulators of fork stability and PARPi responses in BRCA-deficient cells, which provides key insights into targeting BRCA-deficient tumors and identifying epigenetic modulators of chemotherapeutic responses.


Assuntos
Proteína BRCA1/deficiência , Proteína BRCA2/deficiência , Enzimas Reparadoras do DNA/metabolismo , Replicação do DNA , Exodesoxirribonucleases/metabolismo , Histonas/metabolismo , Proteína Homóloga a MRE11/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo , Acetilação/efeitos dos fármacos , Sequência de Aminoácidos , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteína BRCA1/metabolismo , Proteína BRCA2/metabolismo , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Replicação do DNA/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Lisina/metabolismo , Modelos Biológicos , Mutação/genética , Fosforilação/efeitos dos fármacos , Fosfosserina/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Ligação Proteica/efeitos dos fármacos , Fatores de Transcrição de p300-CBP/química , Fatores de Transcrição de p300-CBP/genética
17.
Nucleic Acids Res ; 48(17): 9694-9709, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32890402

RESUMO

DNA breaks recruit and activate PARP1/2, which deposit poly-ADP-ribose (PAR) to recruit XRCC1-Ligase3 and other repair factors to promote DNA repair. Clinical PARP inhibitors (PARPi) extend the lifetime of damage-induced PARP1/2 foci, referred to as 'trapping'. To understand the molecular nature of 'trapping' in cells, we employed quantitative live-cell imaging and fluorescence recovery after photo-bleaching. Unexpectedly, we found that PARP1 exchanges rapidly at DNA damage sites even in the presence of clinical PARPi, suggesting the persistent foci are not caused by physical stalling. Loss of Xrcc1, a major downstream effector of PAR, also caused persistent PARP1 foci without affecting PARP1 exchange. Thus, we propose that the persistent PARP1 foci are formed by different PARP1 molecules that are continuously recruited to and exchanging at DNA lesions due to attenuated XRCC1-LIG3 recruitment and delayed DNA repair. Moreover, mutation analyses of the NAD+ interacting residues of PARP1 showed that PARP1 can be physically trapped at DNA damage sites, and identified H862 as a potential regulator for PARP1 exchange. PARP1-H862D, but not PARylation-deficient PARP1-E988K, formed stable PARP1 foci upon activation. Together, these findings uncovered the nature of persistent PARP1 foci and identified NAD+ interacting residues involved in the PARP1 exchange.


Assuntos
Dano ao DNA , Reparo do DNA/efeitos dos fármacos , Poli(ADP-Ribose) Polimerase-1/genética , Poli(ADP-Ribose) Polimerase-1/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Sítios de Ligação , Domínio Catalítico , Linhagem Celular Tumoral , Reparo do DNA/fisiologia , Transferência Ressonante de Energia de Fluorescência , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Indazóis/farmacologia , Cinética , Imagem Molecular , NAD/metabolismo , Piperidinas/farmacologia , Poli(ADP-Ribose) Polimerases/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteína 1 Complementadora Cruzada de Reparo de Raio-X/genética , Proteína 1 Complementadora Cruzada de Reparo de Raio-X/metabolismo
18.
Gene ; 759: 145000, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32717310

RESUMO

Upregulation of the ATP-binding cassette (ABC) transporter is one of the most important factors leading to multidrug resistance (MDR) in several types of cancer. In the present study, we investigated the ability of rucaparib, a Poly (ADP-ribose) polymerase (PARP) inhibitor which is currently in clinical development, on overcoming ABC transporters-mediated MDR in cervical cancer cell lines. Rucaparib significantly enhanced the cytotoxic effects of a series of conventional chemotherapeutic drugs in drug resistance cervical cancer cell lines. Moreover, rucaparib significantly increased the accumulation of rhodamine 123 in doxorubicin- and paclitaxel-resistance cervical cancer cell lines. In addition, rucaparib significantly increased the accumulation of tritium-labeled chemotherapeutic drugs in drug resistance cervical cancer cells, and decrease the efflux of tritium-labeled chemotherapeutic drugs. Molecular docking study indicated that rucaparib could bind to the active site of the ABC transporters. The present study indicated that rucaparib could antagonize MDR in cervical cancer cells by blocking the function of ABC transporters. The results obtained in the present study provide the potential possibilities that the combination of rucaparib with other chemotherapeutic agents may benefit patients with cervical cancer.


Assuntos
Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Indóis/farmacologia , Simulação de Acoplamento Molecular , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Neoplasias do Colo do Útero/metabolismo , Transportadores de Cassetes de Ligação de ATP/química , Transportadores de Cassetes de Ligação de ATP/metabolismo , Sítios de Ligação , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Sinergismo Farmacológico , Feminino , Humanos , Ligação Proteica
19.
Cancer Sci ; 111(9): 3111-3121, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32639661

RESUMO

Cancer cells are often characterized by abnormalities in DNA damage response including defects in cell cycle checkpoints and/or DNA repair. Synthetic lethality between DNA damage repair (DDR) pathways has provided a paradigm for cancer therapy by targeting DDR. The successful example is that cancer cells with BRCA1/2 mutations are sensitized to poly(adenosine diphosphate [ADP]-ribose)polymerase (PARP) inhibitors. Beyond the narrow scope of defects in the BRCA pathway, "BRCAness" provides more opportunities for synthetic lethality strategy. In human pancreatic cancer, frequent mutations were found in cell cycle and DDR genes, including P16, P73, APC, MLH1, ATM, PALB2, and MGMT. Combined DDR inhibitors and chemotherapeutic agents are under preclinical or clinical trials. Promoter region methylation was found frequently in cell cycle and DDR genes. Epigenetics joins the Knudson's "hit" theory and "BRCAness." Aberrant epigenetic changes in cell cycle or DDR regulators may serve as a new avenue for synthetic lethality strategy in pancreatic cancer.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias Pancreáticas/etiologia , Mutações Sintéticas Letais , Animais , Ciclo Celular/genética , Quimiorradioterapia , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Suscetibilidade a Doenças , Epigênese Genética/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/terapia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo , Transdução de Sinais
20.
Proc Natl Acad Sci U S A ; 117(30): 17785-17795, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32651270

RESUMO

Poly(ADP ribose) polymerase inhibitors (PARPi) have efficacy in triple negative breast (TNBC) and ovarian cancers (OCs) harboring BRCA mutations, generating homologous recombination deficiencies (HRDs). DNA methyltransferase inhibitors (DNMTi) increase PARP trapping and reprogram the DNA damage response to generate HRD, sensitizing BRCA-proficient cancers to PARPi. We now define the mechanisms through which HRD is induced in BRCA-proficient TNBC and OC. DNMTi in combination with PARPi up-regulate broad innate immune and inflammasome-like signaling events, driven in part by stimulator of interferon genes (STING), to unexpectedly directly generate HRD. This inverse relationship between inflammation and DNA repair is critical, not only for the induced phenotype, but also appears as a widespread occurrence in The Cancer Genome Atlas datasets and cancer subtypes. These discerned interactions between inflammation signaling and DNA repair mechanisms now elucidate how epigenetic therapy enhances PARPi efficacy in the setting of BRCA-proficient cancer. This paradigm will be tested in a phase I/II TNBC clinical trial.


Assuntos
Recombinação Homóloga/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Proteína BRCA1/genética , Proteína BRCA2/genética , Linhagem Celular Tumoral , Biologia Computacional , Metilases de Modificação do DNA/antagonistas & inibidores , Reparo do DNA/efeitos dos fármacos , Anemia de Fanconi/genética , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Interferons/metabolismo , Proteínas de Membrana/metabolismo , Modelos Biológicos , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Fator de Necrose Tumoral alfa/metabolismo
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