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1.
Cancer Radiother ; 23(6-7): 662-665, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31473087

RESUMO

Chemoradiotherapy is now considered the standard of care for many locally advanced diseases. Cytotoxic drugs have been largely evaluated in this setting, with cisplatin and 5FU the most often used drugs. A large amount of pre-clinical studies has demonstrated the synergy between both modalities. Concomitant administration seems the more beneficial in many diseases. Emergence of new approaches, combining targeted therapies and radiotherapy (RT) is now a reality. The main example is the association of cetuximab and RT in head and neck carcinomas, even if, 14 years after the initial publication, the best way to use it is still unknown. New compounds as inhibitors of DNA-repair or immune checkpoints are under investigation and showed early promising results.


Assuntos
Antineoplásicos/administração & dosagem , Quimiorradioterapia/tendências , Neoplasias/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cetuximab/administração & dosagem , Quimiorradioterapia/métodos , Cisplatino/administração & dosagem , Reparo do DNA/efeitos dos fármacos , Docetaxel/administração & dosagem , Esquema de Medicação , Fluoruracila/administração & dosagem , Humanos , Terapia de Alvo Molecular/métodos , Órgãos em Risco/efeitos da radiação , Lesões por Radiação/prevenção & controle , Fatores de Tempo
2.
Anticancer Res ; 39(9): 4805-4810, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31519582

RESUMO

BACKGROUND/AIM: Ro 90-7501 has been reported as an inhibitor of the amyloid ß42 fibril assembly that is associated with Alzheimer's disease. The present study aimed to elucidate the radiosensitizing effects of Ro 90-7501 and focused on ATM signaling after irradiation. MATERIALS AND METHODS: Clonogenic survival, apoptosis, and cell-cycle assays as well as western blotting were performed in HeLa cells treated with irradiation and Ro 90-7501. Tumor growth delay assay was also performed using BALB/c-nu mice. RESULTS: The combination of irradiation with Ro 90-7501 showed significant radiosensitizing effects in clonogenic survival and tumor growth delay assays. Ro 90-7501 significantly increased apoptosis and impaired cell cycle after irradiation. Western blotting showed that Ro 90-7501 suppressed the phosphorylation of ATM and its downstream proteins, such as H2AX, Chk1, and Chk2, after irradiation. CONCLUSION: Ro 90-7501 inhibits DNA damage response by inhibiting ATM and has significant radiosensitizing effects on cervical cancer cells.


Assuntos
Aminas/farmacologia , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Benzimidazóis/farmacologia , Radiossensibilizantes/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/efeitos da radiação , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Humanos , Camundongos , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Neoplasias do Colo do Útero/metabolismo
3.
Expert Opin Investig Drugs ; 28(9): 771-785, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31449760

RESUMO

Introduction: Molecular analyzes including molecular descriptor/phenotype interactions have led to better characterization of epithelial ovarian cancer patients, including a definition of a BRCA wild-type (BRCAwt) phenotype. Understanding how and when to use agents targeted against dependent BRCAwt pathways or other molecular events at disease progression is an important translational and therapeutic direction in ovarian cancer research. Areas covered: In this overview, we provide definitions and descriptions of a BRCAwt genotype and phenotype. We discuss novel investigational drugs that hold promise for the treatment of BRCAwt ovarian cancer, including inhibitors of poly(ADP-ribose) polymerase, ribonucleotide reductase, DNA protein kinase-catalytic subunit, ataxia-telangiectasia-mutated kinase (ATM), ataxia-telangiectasia mutated and Rad3-related kinase (ATR), CHK 1/2, cyclin kinases, glutaminase-1, WEE1 kinase, as well as tumor microenvironment and angiogenesis inhibitors. This article explores the known and the emerging areas of clinical research on patients with BRCAwt ovarian cancer. Expert opinion: Discovery of molecular changes tied to annotated disease information, along with an expanding array of pathway targets and targeted therapeutic agents, creates optimism and opportunity for women with ovarian cancer. Using precision oncology approaches, clinical researchers are, and will be, poised to select more effective treatments for ovarian cancer patients.


Assuntos
Antineoplásicos/farmacologia , Terapia de Alvo Molecular , Neoplasias Ovarianas/tratamento farmacológico , Animais , Proteína BRCA1/genética , Proteína BRCA2/genética , Carcinoma Epitelial do Ovário/tratamento farmacológico , Carcinoma Epitelial do Ovário/genética , Carcinoma Epitelial do Ovário/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Drogas em Investigação/farmacologia , Feminino , Humanos , Gradação de Tumores , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia
5.
Chemistry ; 25(47): 11085-11097, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31219221

RESUMO

Naphthalene diimide (NDI) dyads exhibiting a different substitution pattern and linker length have been synthesised and evaluated as G-quadruplex (G4) ligands, by investigating their cytotoxicity in selected cell lines. The dyads with the long C7 linker exhibit extremely low IC50 values, below 10 nm, on different cancer cell lines. Contrary, the dyads with the shorter C4 linker were much less effective, with IC values increasing up to 1 µm. Among the three dyads with the longest linker, small differences in the IC50 values emerge, suggesting that the linker length plays a more important role than the substitution pattern. We have further shown that the dyads are able to induce cellular DNA damage response, which is not limited to the telomeric regions and is likely the origin of their cytotoxicity. Both absorption titration and dynamic light scattering of the most cytotoxic dyads in the presence of hTel22 highlight their ability to induce effective G4 aggregation, acting as non-covalent cross-linking agents.


Assuntos
Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Quadruplex G , Imidas/farmacologia , Naftalenos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Imidas/síntese química , Imidas/química , Ligantes , Metáfase/efeitos dos fármacos , Microscopia de Fluorescência , Naftalenos/síntese química , Naftalenos/química , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Telômero/efeitos dos fármacos , Telômero/metabolismo
6.
Cancer Res ; 79(10): 2460-2461, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31092408

RESUMO

There is extensive literature on PARP1, owing to the multiple functions of PARP1 for DNA repair, aging, chromatin remodeling and transcription, and to the successful clinical development of four PARP inhibitors. In this issue of Cancer Research, Wang and colleagues identified phosphatase 1 nuclear targeting subunit (PNUTS, also referred to as PP1R10) as a partner of PARP1 and demonstrated that PNUTS and PARP1 are interdependent for their recruitment to DNA damage sites. As PARP1 is a prominent target for cancer therapy and PNUTS has PARP-dependent as well as PARP1-independent activities, the findings of Wang and colleagues add insight into DNA repair mechanisms with potential application to drug targeting and precision therapy.See related article by Wang et al., p. 2526.


Assuntos
Reparo do DNA/efeitos dos fármacos , Inibidores de Poli(ADP-Ribose) Polimerases , Dano ao DNA/efeitos dos fármacos , Monoéster Fosfórico Hidrolases/genética , Poli(ADP-Ribose) Polimerase-1/genética
7.
Mol Biol (Mosk) ; 53(2): 311-323, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31099781

RESUMO

The CRISPR/Cas9 nuclease system can effectively suppress the replication of the hepatitis B virus (HBV), while covalently closed circular DNA (cccDNA), a highly resistant form of the virus, persists in the nuclei of infected cells. The most common outcome of DNA double-strand breaks (DSBs) in cccDNA caused by CRISPR/Cas9 is double-strand break repair by nonhomologous end-joining, which results in insertion/deletion mutations. Modulation of the DNA double-strand break repair pathways by small molecules was shown to stimulate CRISPR/Cas9 activity and may potentially be utilized to enhance the elimination of HBV cccDNA. In this work, we used inhibitors of homologous (RI-1) and nonhomologous (NU7026) end-joining and their combination to stimulate antiviral activity of CRISPR/Cas9 on two cell models of HBV in vitro, i.e., the HepG2-1.1merHBV cells containing the HBV genome under the tet-on regulated cytomegalovirus promoter and the HepG2-1.5merHBV cells containing constitutive expression of HBV RNA under the wild-type promoter. The treatment of the cells with RI-1 or NU7026 after lentiviral transduction of CRISPR/Cas9 drops the levels of cccDNA compared to the DMSO-treated control. RI-1 and NU7026 resulted in 5.0-6.5 times more significant reduction in the HBV cccDNA level compared to the mock-control. In conclusion, the inhibition of both homologous and nonhomologous DNA double-strand break repair pathways increases the elimination of HBV cccDNA by CRISPR/Cas9 system in vitro, which may potentially be utilized as a therapeutic approach to treat chronic hepatitis B.


Assuntos
Proteína 9 Associada à CRISPR/metabolismo , Sistemas CRISPR-Cas/efeitos dos fármacos , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , DNA Viral/metabolismo , Vírus da Hepatite B , Sistemas CRISPR-Cas/genética , DNA Circular/genética , DNA Circular/metabolismo , DNA Viral/genética
8.
Arch Microbiol ; 201(7): 991-998, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31025056

RESUMO

Caffeine is a compound that can exert physiological-beneficial effects in the organism. Nevertheless, there are controversies about its protective-antioxidant and/or its negative genotoxic effect. To abound on the analysis of the possible genotoxic/antioxidant effect of caffeine, we used as research model the yeast Yarrowia lipolytica parental strain, and mutant strains (∆rad52 and ∆ku80), which are deficient in the DNA repair mechanisms. Caffeine (5 mM) showed a cytostatic effect on all strains, but after 72 h of incubation the parental and ∆ku80 strains were able to recover of this inhibitory effect on growth, whereas ∆rad52 was unable to recover. When cells were pre-incubated with caffeine and H2O2 or incubated with a mixture of both agents, a higher inhibitory effect on growth of mutant strains was observed and this effect was noticeably greater for the Δrad52 strain. The toxic effect of caffeine appears to be through a mechanism of DNA damage (genotoxic effect) that involves DSB generation since, in all tested conditions, the growth of Δrad52 strain (cells deficient in HR DNA repair mechanism) was more severely affected.


Assuntos
Cafeína/toxicidade , Reparo do DNA/genética , Yarrowia/efeitos dos fármacos , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Mutação/genética , Yarrowia/genética , Yarrowia/crescimento & desenvolvimento
9.
Oncol Rep ; 41(6): 3517-3526, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31002359

RESUMO

Resveratrol, a plant­derived stilbene compound, has exhibited anticancerous properties, including breast cancer. Stilbenes have a molecular structure highly similar to estrogen and have the ability to bind estrogen receptors and regulate activity. Numerous studies have demonstrated the effectiveness of resveratrol in estrogen receptor­positive (ER­positive) subtypes of breast cancer, yet the effects in ER­negative subtypes, including triple­negative breast cancer (TNBC), have been limited. In the present study, resveratrol and 28 analogues were tested on a panel of ER­positive and TNBC cell lines to determine effects on cell viability. Several compounds exhibited significant impacts on cell viability and suggested changes in cell morphology, with high potency of select compounds compared to resveratrol observed in a dose­dependent manner. Due to the lack of estrogen receptors in TNBC and the estrogenic nature of stilbenes, regulation of breast cancer­associated cellular pathways was assessed for five analogues shown to significantly inhibit cell viability. Top regulated pathways included apoptosis (confirmed by caspase assay) and DNA damage repair. Overall, our results indicated several resveratrol analogues to be active in ER­negative phenotypes, acting through an ER receptor­independent manner, supporting further investigation into their mechanism of action and use as potential chemotherapeutics in higher­risk breast cancer cases.


Assuntos
Proliferação de Células/efeitos dos fármacos , Receptor alfa de Estrogênio/genética , Resveratrol/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Feminino , Humanos , Transdução de Sinais/efeitos dos fármacos , Estilbenos/farmacologia , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia
10.
Cancer Discov ; 9(4): 469-471, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30936219

RESUMO

In this issue, Maertens and colleagues demonstrate that HDAC3 inhibition potentiates the effects of MAPK pathway inhibitors in melanoma, including difficult-to-treat NRAS- and NF1-driven tumors, with MGMT expression serving as a biomarker for responsiveness to the BRAF/MEK/HDAC inhibitor combination. Mechanistically, this triple cocktail suppresses expression of genes involved in DNA repair, leading to enhanced killing of melanoma cells.See related article by Maertens et al., p. 526.


Assuntos
Melanoma/genética , Proteínas Proto-Oncogênicas B-raf/genética , Reparo do DNA/efeitos dos fármacos , GTP Fosfo-Hidrolases/genética , Humanos , Proteínas de Membrana/genética , Inibidores de Proteínas Quinases
11.
Toxicol Lett ; 310: 92-98, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30999038

RESUMO

Fullerenes have attracted attention since their discovery as structural units of complex carbon nanostructures capable of transporting drugs and macromolecules. As such artificial nanomaterials are applied in biology and medicine, they are routinely scrutinized for their effects on living organisms. The results of such studies range from direct destabilizing effects on DNA molecules to amelioration of the toxic effects of known genotoxic agents. We tested the effect of buckminsterfullerene (C60) on Drosophila melanogaster at DNA, tissue and organism levels. The water-soluble pristine C60 fullerene at the concentration of 20 µg/ml and 40 µg/ml leads to the activation of the mus209 gene in D. melanogaster larvae salivary glands, which can indicate higher levels of DNA damage. However, the absence of effects at the cell and organismal level could be explained by the activation of repair systems or by active elimination of damaged cells.


Assuntos
Drosophila melanogaster/efeitos dos fármacos , Fulerenos/toxicidade , Nanopartículas/toxicidade , Glândulas Salivares/efeitos dos fármacos , Animais , Animais Geneticamente Modificados , Dano ao DNA , Reparo do DNA/efeitos dos fármacos , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/embriologia , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Masculino , Testes de Mutagenicidade , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Medição de Risco , Glândulas Salivares/embriologia , Glândulas Salivares/metabolismo , Ativação Transcricional/efeitos dos fármacos
12.
Anticancer Res ; 39(4): 1839-1847, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30952724

RESUMO

BACKGROUND/AIM: Casticin shows anti-cancer effects in many types of cancer. However, there is no information regarding its role in DNA damage in human bladder cancer. The aim of this study was to investigate the effects of casticin on TSGH-8301 cells in vitro. MATERIALS AND METHODS: Viability of cells was assayed by flow cytometry. DNA damage was assayed by DAPI staining, comet assay, and gel electrophoresis. Protein levels were examined by western blotting and confocal laser microscopy. RESULTS: Casticin decreased viability of cells and induced DNA damage. Furthermore, casticin decreased expression of p-ATM, p-ATR, MDC1 and MGMT levels after 48 h of treatment, however, it increased p-ATR and MGMT levels after 12 h. In contrast, casticin increased the levels of p-p53, p-H2A.X, and PARP after 48 h of treatment. As shown by confocal microscopy, casticin affected the translocation of DNA-PKcs and p-p53 to the nucleus of TSGH-8301 cells. CONCLUSION: Casticin decreased viability of human bladder cancer cells through DNA damage.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Dano ao DNA , Reparo do DNA/efeitos dos fármacos , Flavonoides/farmacologia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Transporte Ativo do Núcleo Celular , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/metabolismo , Proteína Quinase Ativada por DNA/metabolismo , Histonas/metabolismo , Humanos , Proteínas Nucleares/metabolismo , Fosforilação , Poli(ADP-Ribose) Polimerases/metabolismo , Transativadores/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia
13.
Eur J Pharmacol ; 851: 174-185, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30836068

RESUMO

Malignant melanoma was the leading cause of mortality among the skin-associated cancer owing to its highly metastatic feature, increasing incidence and drug resistance requirement. Retinoids played important roles in the treatment of cancer via the activation of retinoid acid receptor (RAR) or retinoid X receptor (RXR). Our present study showed that the third-generation retinoid adapalene exhibited strong inhibitory effects on the proliferation of melanoma cells than other retinoids, such as all-trans-retinoic acid (ATRA), isotretinoin, acitretin and bexarotene, and adapalene exerted significant inhibitory effects on the colony formation of melanoma cells. Further study confirmed that adapalene treatment triggered dramatic S phase arrest and apoptosis, and S phase arrest was the potential mechanism of apoptosis induction. In addition, adapalene treatment dramatically regulated the expression of S phase-related protein, and increased the protein level of DNA damage marker,which were consistent with the results of the induction of the tail moment in comet assays. Meanwhile, DNA damage response was activated and the DNA repair pathway was simultaneously inhibited by adapalene treatment, which might furtherly potentiate S phase arrest and subsequent apoptosis. Taken together, these results showed that adapalene exhibited strong anti-cancer activity, and might be a candidate agent for the clinical treatment of melanoma.


Assuntos
Adapaleno/farmacologia , Apoptose/efeitos dos fármacos , Dano ao DNA , Melanoma/patologia , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Humanos , Receptores do Ácido Retinoico/metabolismo
14.
J Cancer Res Ther ; 15(Supplement): S153-S158, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30900638

RESUMO

Objective: The complete molecular mechanism that cyclophosphamide (CPA) induces the cell death is still unknown. To further reveal the mechanism of CPA contributing to prostate cancer, we conducted analysis on gene expression profile of E-GEOD-42913 to identify attractor modules by integrating systemic module inference with attract method. Methods: First, case and control protein-protein interaction (PPI) networks were inferred based on Spearman correlation coefficient; then clique merging algorithm was performed to explore modules in the reweighted PPI network, and these modules were compared with each other so as to select similar modules; in the following, attractor modules were identified via attract method; finally, pathway enrichment analysis of genes in attractor modules was carried out. Results: A total of 11,535 genes were gained. A novel PPI network with 4698 nodes (20,541 interactions) was established via mapping the genes of the gene expression profile onto the original PPIs. Then, 1635 and 1487 interactions (P < 0.05) were selected to construct the destination network for CPA group and control group, respectively. Moreover, under the threshold value of overlap -threshold value of each two modules ≥ 0.5, 42 and 56 modules were separately determined for CPA group and control group. Twenty-six pairs of similar modules ([J (Sn, Tm)] ≥0.7) were gained. In the following, an attractor module which contained six nodes (15 interactions) (P < 0.05) was identified. Finally, two pathways with terms of DNA replication (P = 0.000137) and nucleotide excision repair (P = 0.024) were identified, and RFC4, POLE2 enriched in both of the pathways. Conclusions: We predicted that during the process of chemotherapy, CPA mainly affected the pathways of DNA replication and nucleotide excision repair to induce the cancer cell's death.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Apoptose/efeitos dos fármacos , Ciclofosfamida/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Algoritmos , Antineoplásicos Alquilantes/uso terapêutico , Apoptose/genética , Biologia Computacional , Ciclofosfamida/uso terapêutico , Reparo do DNA/efeitos dos fármacos , Replicação do DNA/efeitos dos fármacos , Conjuntos de Dados como Assunto , Perfilação da Expressão Gênica , Redes Reguladoras de Genes/efeitos dos fármacos , Redes Reguladoras de Genes/genética , Humanos , Masculino , Neoplasias da Próstata/patologia , Mapas de Interação de Proteínas/efeitos dos fármacos , Mapas de Interação de Proteínas/genética
15.
BMC Cancer ; 19(1): 179, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30813936

RESUMO

BACKGROUND: Daunorubicin is commonly used in the treatment of acute lymphoblastic leukaemia (ALL). The aim of this study was to explore the kinetics of double strand break (DSB) formation of three ALL cell lines following exposure to daunorubicin and to investigate the effects of daunorubicin on the cell cycle and the protein kinases involved in specific checkpoints following DNA damage and recovery periods. METHODS: Three ALL cell lines CCRF-CEM and MOLT-4 derived from T lymphocytes and SUP-B15 derived from B lymphocytes were examined following 4 h treatment with daunorubicin chemotherapy and 4, 12 and 24 h recovery periods. Cell viability was measured via MTT (3-(4,5-dimethylthiazol-2-yl)-2-5 diphenyltetrazolium bromide) assay, reactive oxygen species (ROS) production by flow cytometry, double stranded DNA breaks by detecting γH2AX levels while stages of the cell cycle were detected following propidium iodide staining and flow cytometry. Western blotting was used to detect specific proteins while RNA was extracted from all cell lines and converted to cDNA to sequence Ataxia-telangiectasia mutated (ATM). RESULTS: Daunorubicin induced different degrees of toxicity in all cell lines and consistently generated reactive oxygen species. Daunorubicin was more potent at inducing DSB in MOLT-4 and CCRF-CEM cell lines while SUP-B15 cells showed delays in DSB repair and significantly more resistance to daunorubicin compared to the other cell lines as measured by γH2AX assay. Daunorubicin also causes cell cycle arrest in all three cell lines at different checkpoints at different times. These effects were not due to mutations in ATM as sequencing revealed none in any of the three cell lines. However, p53 was phosphorylated at serine 15 only in CCRF-CEM and MOLT-4 but not in SUP-B15 cells. The lack of active p53 may be correlated to the increase of SOD2 in SUP-B15 cells. CONCLUSIONS: The delay in DSB repair and lower sensitivity to daunorubicin seen in the B lymphocyte derived SUP-B15 cells could be due to loss of function of p53 that may be correlated to increased expression of SOD2 and lower ROS production.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Ciclo Celular/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Daunorrubicina/farmacologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Quebras de DNA de Cadeia Dupla , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
16.
Chem Asian J ; 14(9): 1570-1576, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-30843348

RESUMO

DNA damage repair through the nucleotide excision repair (NER) pathway is one of the major reasons for the decreased antitumor efficacy of platinum-based anticancer drugs that have been widely applied in the clinic. Inhibiting the intrinsic NER function may enhance the antitumor activity of cisplatin and conquer cisplatin resistance. Herein, we report the design, optimization, and application of a self-assembled lipid nanoparticle (LNP) system to simultaneously deliver a cisplatin prodrug together with siRNA targeting endonuclease xeroderma pigmentosum group F (XPF), a crucial component in the NER pathway. The LNP is able to efficiently encapsulate both the platinum prodrug and siRNA molecules with a tuned ratio. Both platinum prodrug and XPF-targeted siRNA are efficiently carried into cells and released; the former damages DNA and the latter specifically downregulates both mRNA and protein levels of XPF to potentiate the platinum drug, leading to enhanced expression levels of apoptosis markers and improved cytotoxicity in both cisplatin-sensitive and -resistant human lung cancer cells. Our results demonstrate an effective approach to utilize a multi-targeted nanoparticle system that can specifically silence an NER-related gene to promote apoptosis induced by cisplatin, especially in cisplatin-refractory tumors.


Assuntos
Antineoplásicos/química , Cisplatino/química , Proteínas de Ligação a DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos , Nanopartículas/química , RNA Interferente Pequeno/química , Células A549 , Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Reparo do DNA/efeitos dos fármacos , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/genética , Portadores de Fármacos/química , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Lipídeos/química , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico , Interferência de RNA , RNA Interferente Pequeno/metabolismo , RNA Interferente Pequeno/uso terapêutico
17.
Reproduction ; 157(3): 223-234, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30817312

RESUMO

Homologous recombination (HR) plays a critical role in facilitating replication fork progression when the polymerase complex encounters a blocking DNA lesion, and it also serves as the primary mechanism for error-free DNA repair of double-stranded breaks. DNA repair protein RAD51 homolog 1 (RAD51) plays a central role in HR. However, the role of RAD51 during porcine early embryo development is unknown. In the present study, we examined whether RAD51 is involved in the regulation of early embryonic development of porcine parthenotes. We found that inhibition of RAD51 delayed cleavage and ceased development before the blastocyst stage. Disrupting RAD51 activity with RNAi or an inhibitor induces sustained DNA damage, as demonstrated by the formation of distinct γH2AX foci in nuclei of four-cell embryos. Inhibiting RAD51 triggers a DNA damage checkpoint by activating the ataxia telangiectasia mutated (ATM)-p53-p21 pathway. Furthermore, RAD51 inhibition caused apoptosis, reactive oxygen species accumulation, abnormal mitochondrial distribution and decreased pluripotent gene expression in blastocysts. Thus, our results indicate that RAD51 is required for proper porcine parthenogenetic activation (PA) embryo development.


Assuntos
Blastocisto/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Rad51 Recombinase/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Blastocisto/metabolismo , Reparo do DNA/efeitos dos fármacos , Feminino , Gravidez , Rad51 Recombinase/metabolismo , Transdução de Sinais/efeitos dos fármacos , Suínos , Proteína Supressora de Tumor p53/metabolismo
18.
Cancer Treat Rev ; 75: 27-38, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30927677

RESUMO

CONTEXT: Pancreatic cancer (PDAC) is one of the most challenging cancers to treat with modest recent improvements in survival from new systemic therapies. There is growing interest in individualized therapy underpinned by somatic and germline genomic alterations. OBJECTIVE: A systematic review of data on therapies targeting somatic and germline alterations, and their downstream pathways in PDAC. METHOD: A systematic literature search was conducted using PRISMA guidelines to include relevant results published after January 1, 2008. RESULTS: A total of 71 relevant studies were included. We identified 36 studies targeting the KRAS-pathway, the most common being with MEK-inhibitor therapy. Twenty-two studies were identified that evaluated platinum-based chemotherapy and PARP inhibitors in patients with deleterious mutations in DNA damage repair genes and have shown encouraging results. Immunotherapy has demonstrated activity in patients with mismatch repair deficiency/microsatellite instability. CONCLUSION: Evidence from translational and clinical research presents an exciting platform for genomic targeted therapy in PDAC. Validity for targeting BRCA with platinum and PARP inhibitors and microsatellite instability with immune therapy has been established, nonetheless, evidence for targeting the common driver oncogenes is lacking and much work is needed. Of importance is identifying the subgroup of KRAS -wild type PDAC (approximately 5%) where there is enrichment for targetable opportunities.


Assuntos
Carcinoma Ductal Pancreático/genética , Neoplasias Pancreáticas/genética , Animais , Carcinoma Ductal Pancreático/tratamento farmacológico , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/genética , Genômica/métodos , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico
19.
J Biol Chem ; 294(14): 5700-5719, 2019 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-30733337

RESUMO

The tumor suppressor bridging integrator 1 (BIN1) is a corepressor of the transcription factor E2F1 and inhibits cell-cycle progression. BIN1 also curbs cellular poly(ADP-ribosyl)ation (PARylation) and increases sensitivity of cancer cells to DNA-damaging therapeutic agents such as cisplatin. However, how BIN1 deficiency, a hallmark of advanced cancer cells, increases cisplatin resistance remains elusive. Here, we report that BIN1 inactivates ataxia telangiectasia-mutated (ATM) serine/threonine kinase, particularly when BIN1 binds E2F1. BIN1 + 12A (a cancer-associated BIN1 splicing variant) also inhibited cellular PARylation, but only BIN1 increased cisplatin sensitivity. BIN1 prevented E2F1 from transcriptionally activating the human ATM promoter, whereas BIN1 + 12A did not physically interact with E2F1. Conversely, BIN1 loss significantly increased E2F1-dependent formation of MRE11A/RAD50/NBS1 DNA end-binding protein complex and efficiently promoted ATM autophosphorylation. Even in the absence of dsDNA breaks (DSBs), BIN1 loss promoted ATM-dependent phosphorylation of histone H2A family member X (forming γH2AX, a DSB biomarker) and mediator of DNA damage checkpoint 1 (MDC1, a γH2AX-binding adaptor protein for DSB repair). Of note, even in the presence of transcriptionally active (i.e. proapoptotic) TP53 tumor suppressor, BIN1 loss generally increased cisplatin resistance, which was conversely alleviated by ATM inactivation or E2F1 reduction. However, E2F2 or E2F3 depletion did not recapitulate the cisplatin sensitivity elicited by E2F1 elimination. Our study unveils an E2F1-specific signaling circuit that constitutively activates ATM and provokes cisplatin resistance in BIN1-deficient cancer cells and further reveals that γH2AX emergence may not always reflect DSBs if BIN1 is absent.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/deficiência , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Fator de Transcrição E2F1/metabolismo , Neoplasias/metabolismo , Proteínas Nucleares/deficiência , Transcrição Genética , Proteínas Supressoras de Tumor/deficiência , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Quebras de DNA de Cadeia Dupla , Reparo do DNA/efeitos dos fármacos , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Fator de Transcrição E2F1/genética , Histonas/genética , Histonas/metabolismo , Humanos , Proteína Homóloga a MRE11/genética , Proteína Homóloga a MRE11/metabolismo , Neoplasias/genética , Neoplasias/patologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Transdução de Sinais/efeitos dos fármacos
20.
Oncogene ; 38(22): 4325-4339, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30705403

RESUMO

PRRX1 is a homeodomain transcriptional factor, which has two isoforms, PRXX1A and PRRX1B. The PRRX1 isoforms have been demonstrated to be important in pancreatic cancer, especially in the regulation of epithelial-to-mesenchymal transition (EMT) in Pancreatic Ductal Adenocarcinoma (PDAC) and of mesenchymal-to-epithelial transition (MET) in liver metastasis. In order to determine the functional underpinnings of PRRX1 and its isoforms, we have unraveled a new interplay between PRRX1 and the FOXM1 transcriptional factors. Our detailed biochemical analysis reveals the direct physical interaction between PRRX1 and FOXM1 proteins that requires the PRRX1A/B 200-222/217 amino acid (aa) region and the FOXM1 Forkhead domain. Additionally, we demonstrate the cooperation between PRRX1 and FOXM1 in the regulation of FOXM1-dependent transcriptional activity. Moreover, we establish FOXM1 as a critical downstream target of PRRX1 in pancreatic cancer cells. We demonstrate a novel role for PRRX1 in the regulation of genes involved in DNA repair pathways. Indeed, we show that expression of PRRX1 isoforms may limit the induction of DNA damage in pancreatic cancer cells. Finally, we demonstrate that targeting FOXM1 with the small molecule inhibitor FDI6 suppress pancreatic cancer cell proliferation and induces their apoptotic cell death. FDI6 sensitizes pancreatic cancer cells to Etoposide and Gemcitabine induced apoptosis. Our data provide new insights into PRRX1's involvement in regulating DNA damage and provide evidence of a possible PRRX1-FOXM1 axis that is critical for PDAC cells.


Assuntos
Dano ao DNA/genética , Proteína Forkhead Box M1/genética , Proteínas de Homeodomínio/genética , Neoplasias Pancreáticas/genética , Isoformas de Proteínas/genética , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/genética , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Transição Epitelial-Mesenquimal , Etoposídeo/farmacologia , Células HEK293 , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Camundongos , Camundongos Knockout , Pâncreas/efeitos dos fármacos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Transcrição Genética/efeitos dos fármacos , Transcrição Genética/genética
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