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1.
Br J Cancer ; 130(7): 1196-1205, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38287178

RESUMO

BACKGROUND: 5-Fluorouracil (5-FU) remains a core component of systemic therapy for colorectal cancer (CRC). However, response rates remain low, and development of therapy resistance is a primary issue. Combinatorial strategies employing a second agent to augment the therapeutic effect of chemotherapy is predicted to reduce the incidence of treatment resistance and increase the durability of response to therapy. METHODS: Here, we employed quantitative proteomics approaches to identify novel druggable proteins and molecular pathways that are deregulated in response to 5-FU, which might serve as targets to improve sensitivity to chemotherapy. Drug combinations were evaluated using 2D and 3D CRC cell line models and an ex vivo culture model of a patient-derived tumour. RESULTS: Quantitative proteomics identified upregulation of the mitosis-associated protein Aurora B (AURKB), within a network of upregulated proteins, in response to a 24 h 5-FU treatment. In CRC cell lines, AURKB inhibition with the dihydrogen phosphate prodrug AZD1152, markedly improved the potency of 5-FU in 2D and 3D in vitro CRC models. Sequential treatment with 5-FU then AZD1152 also enhanced the response of a patient-derived CRC cells to 5-FU in ex vivo cultures. CONCLUSIONS: AURKB inhibition may be a rational approach to augment the effectiveness of 5-FU chemotherapy in CRC.


Assuntos
Neoplasias Colorretais , Fluoruracila , Organofosfatos , Quinazolinas , Humanos , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , Apoptose , Aurora Quinase B/farmacologia , Aurora Quinase B/uso terapêutico , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Resistencia a Medicamentos Antineoplásicos
2.
Prostate ; 83(7): 628-640, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36811381

RESUMO

BACKGROUND: Activation and regulation of androgen receptor (AR) signaling and the DNA damage response impact the prostate cancer (PCa) treatment modalities of androgen deprivation therapy (ADT) and radiotherapy. Here, we have evaluated a role for human single-strand binding protein 1 (hSSB1/NABP2) in modulation of the cellular response to androgens and ionizing radiation (IR). hSSB1 has defined roles in transcription and maintenance of genome stability, yet little is known about this protein in PCa. METHODS: We correlated hSSB1 with measures of genomic instability across available PCa cases from The Cancer Genome Atlas (TCGA). Microarray and subsequent pathway and transcription factor enrichment analysis were performed on LNCaP and DU145 prostate cancer cells. RESULTS: Our data demonstrate that hSSB1 expression in PCa correlates with measures of genomic instability including multigene signatures and genomic scars that are reflective of defects in the repair of DNA double-strand breaks via homologous recombination. In response to IR-induced DNA damage, we demonstrate that hSSB1 regulates cellular pathways that control cell cycle progression and the associated checkpoints. In keeping with a role for hSSB1 in transcription, our analysis revealed that hSSB1 negatively modulates p53 and RNA polymerase II transcription in PCa. Of relevance to PCa pathology, our findings highlight a transcriptional role for hSSB1 in regulating the androgen response. We identified that AR function is predicted to be impacted by hSSB1 depletion, whereby this protein is required to modulate AR gene activity in PCa. CONCLUSIONS: Our findings point to a key role for hSSB1 in mediating the cellular response to androgen and DNA damage via modulation of transcription. Exploiting hSSB1 in PCa might yield benefits as a strategy to ensure a durable response to ADT and/or radiotherapy and improved patient outcomes.


Assuntos
Proteínas de Ligação a DNA , Proteínas Mitocondriais , Neoplasias da Próstata , Humanos , Masculino , Antagonistas de Androgênios/farmacologia , Androgênios/metabolismo , Linhagem Celular Tumoral , Dano ao DNA , Reparo do DNA , Proteínas de Ligação a DNA/metabolismo , Instabilidade Genômica , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Receptores Androgênicos/genética , Proteínas Mitocondriais/metabolismo
3.
Br J Cancer ; 129(12): 2014-2024, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37914802

RESUMO

BACKGROUND: Lung cancer is the biggest cause of cancer-related deaths worldwide. Non-small cell lung cancer (NSCLC) accounts for 85-90% of all lung cancers. Identification of novel therapeutic targets are required as drug resistance impairs chemotherapy effectiveness. COMMD4 is a potential NSCLC therapeutic target. The aims of this study were to investigate the COMMD4-H2B binding pose and develop a short H2B peptide that disrupts the COMMD4-H2B interaction and mimics COMMD4 siRNA depletion. METHODS: Molecular modelling, in vitro binding and site-directed mutagenesis were used to identify the COMMD4-H2B binding pose and develop a H2B peptide to inhibit the COMMD4-H2B interaction. Cell viability, DNA repair and mitotic catastrophe assays were performed to determine whether this peptide can specially kill NSCLC cells. RESULTS: Based on the COMMD4-H2B binding pose, we have identified a H2B peptide that inhibits COMMD4-H2B by directly binding to COMMD4 on its H2B binding binding site, both in vitro and in vivo. Treatment of NSCLC cell lines with this peptide resulted in increased sensitivity to ionising radiation, increased DNA double-strand breaks and induction of mitotic catastrophe in NSCLC cell lines. CONCLUSIONS: Our data shows that COMMD4-H2B represents a novel potential NSCLC therapeutic target.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Reparo do DNA , Peptídeos/genética
4.
Phys Chem Chem Phys ; 25(36): 24657-24677, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37665626

RESUMO

Barrier-to-autointegration factor (Banf1) is a small DNA-bridging protein. The binding status of Banf1 to DNA is regulated by its N-terminal phosphorylation and dephosphorylation, which plays a critical role in cell proliferation. Banf1 can be phosphorylated at Ser4 into mono-phosphorylated Banf1, which is further phosphorylated at Thr3 to form di-phosphorylated Banf1. It was observed decades ago that mono-phosphorylated Banf1 cannot bind to DNA. However, the underlying molecular- and atomic-level mechanisms remain unclear. A clear understanding of these mechanisms will aid in interfering with the cell proliferation process for better global health. Herein, we explored the detailed atomic bases of unphosphorylated Banf1-DNA binding and how mono- and di-phosphorylation of Banf1 impair these atomic bases to eliminate its DNA-binding capability, followed by exploring the DNA-binding capability of mono- and di-phosphorylation Banf1, using comprehensive and systematic molecular modelling and molecular dynamics simulations. This work presented in detail the residue-level binding energies, hydrogen bonds and water bridges between Banf1 and DNA, some of which have not been reported. Moreover, we revealed that mono-phosphorylation of Banf1 causes its N-terminal secondary structure changes, which in turn induce significant changes in Banf1's DNA binding surface, thus eliminating its DNA-binding capability. At the atomic level, we also uncovered the alterations in interactions due to the induction of mono-phosphorylation that result in the N-terminal secondary structure changes of Banf1. Additionally, our modelling showed that phosphorylated Banf1 with their dominant N-terminal secondary structures bind to DNA with a significantly lower affinity and the docked binding pose are not stable in MD simulations. These findings help future studies in predicting effect of mutations in Banf1 on its DNA-binding capability and open a novel avenue for the development of therapeutics such as cancer drugs, targeting cell proliferation by inducing conformational changes in Banf1's N-terminal domain.


Assuntos
Simulação de Dinâmica Molecular , Fosforilação , Conformação Molecular , Proliferação de Células , Ligação de Hidrogênio
5.
N Engl J Med ; 381(21): 2020-2031, 2019 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-31562796

RESUMO

BACKGROUND: In an early-phase study involving patients with advanced non-small-cell lung cancer (NSCLC), the response rate was better with nivolumab plus ipilimumab than with nivolumab monotherapy, particularly among patients with tumors that expressed programmed death ligand 1 (PD-L1). Data are needed to assess the long-term benefit of nivolumab plus ipilimumab in patients with NSCLC. METHODS: In this open-label, phase 3 trial, we randomly assigned patients with stage IV or recurrent NSCLC and a PD-L1 expression level of 1% or more in a 1:1:1 ratio to receive nivolumab plus ipilimumab, nivolumab alone, or chemotherapy. The patients who had a PD-L1 expression level of less than 1% were randomly assigned in a 1:1:1 ratio to receive nivolumab plus ipilimumab, nivolumab plus chemotherapy, or chemotherapy alone. All the patients had received no previous chemotherapy. The primary end point reported here was overall survival with nivolumab plus ipilimumab as compared with chemotherapy in patients with a PD-L1 expression level of 1% or more. RESULTS: Among the patients with a PD-L1 expression level of 1% or more, the median duration of overall survival was 17.1 months (95% confidence interval [CI], 15.0 to 20.1) with nivolumab plus ipilimumab and 14.9 months (95% CI, 12.7 to 16.7) with chemotherapy (P = 0.007), with 2-year overall survival rates of 40.0% and 32.8%, respectively. The median duration of response was 23.2 months with nivolumab plus ipilimumab and 6.2 months with chemotherapy. The overall survival benefit was also observed in patients with a PD-L1 expression level of less than 1%, with a median duration of 17.2 months (95% CI, 12.8 to 22.0) with nivolumab plus ipilimumab and 12.2 months (95% CI, 9.2 to 14.3) with chemotherapy. Among all the patients in the trial, the median duration of overall survival was 17.1 months (95% CI, 15.2 to 19.9) with nivolumab plus ipilimumab and 13.9 months (95% CI, 12.2 to 15.1) with chemotherapy. The percentage of patients with grade 3 or 4 treatment-related adverse events in the overall population was 32.8% with nivolumab plus ipilimumab and 36.0% with chemotherapy. CONCLUSIONS: First-line treatment with nivolumab plus ipilimumab resulted in a longer duration of overall survival than did chemotherapy in patients with NSCLC, independent of the PD-L1 expression level. No new safety concerns emerged with longer follow-up. (Funded by Bristol-Myers Squibb and Ono Pharmaceutical; CheckMate 227 ClinicalTrials.gov number, NCT02477826.).


Assuntos
Antineoplásicos Imunológicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Ipilimumab/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Nivolumabe/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Imunológicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Antígeno B7-H1/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Feminino , Humanos , Ipilimumab/efeitos adversos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Nivolumabe/efeitos adversos , Análise de Sobrevida
6.
N Engl J Med ; 378(22): 2093-2104, 2018 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-29658845

RESUMO

BACKGROUND: Nivolumab plus ipilimumab showed promising efficacy for the treatment of non-small-cell lung cancer (NSCLC) in a phase 1 trial, and tumor mutational burden has emerged as a potential biomarker of benefit. In this part of an open-label, multipart, phase 3 trial, we examined progression-free survival with nivolumab plus ipilimumab versus chemotherapy among patients with a high tumor mutational burden (≥10 mutations per megabase). METHODS: We enrolled patients with stage IV or recurrent NSCLC that was not previously treated with chemotherapy. Those with a level of tumor programmed death ligand 1 (PD-L1) expression of at least 1% were randomly assigned, in a 1:1:1 ratio, to receive nivolumab plus ipilimumab, nivolumab monotherapy, or chemotherapy; those with a tumor PD-L1 expression level of less than 1% were randomly assigned, in a 1:1:1 ratio, to receive nivolumab plus ipilimumab, nivolumab plus chemotherapy, or chemotherapy. Tumor mutational burden was determined by the FoundationOne CDx assay. RESULTS: Progression-free survival among patients with a high tumor mutational burden was significantly longer with nivolumab plus ipilimumab than with chemotherapy. The 1-year progression-free survival rate was 42.6% with nivolumab plus ipilimumab versus 13.2% with chemotherapy, and the median progression-free survival was 7.2 months (95% confidence interval [CI], 5.5 to 13.2) versus 5.5 months (95% CI, 4.4 to 5.8) (hazard ratio for disease progression or death, 0.58; 97.5% CI, 0.41 to 0.81; P<0.001). The objective response rate was 45.3% with nivolumab plus ipilimumab and 26.9% with chemotherapy. The benefit of nivolumab plus ipilimumab over chemotherapy was broadly consistent within subgroups, including patients with a PD-L1 expression level of at least 1% and those with a level of less than 1%. The rate of grade 3 or 4 treatment-related adverse events was 31.2% with nivolumab plus ipilimumab and 36.1% with chemotherapy. ical; CheckMate 227 ClinicalTrials.gov number, NCT02477826 .). CONCLUSIONS: Progression-free survival was significantly longer with first-line nivolumab plus ipilimumab than with chemotherapy among patients with NSCLC and a high tumor mutational burden, irrespective of PD-L1 expression level. The results validate the benefit of nivolumab plus ipilimumab in NSCLC and the role of tumor mutational burden as a biomarker for patient selection. (Funded by Bristol-Myers Squibb and Ono Pharmaceut


Assuntos
Anticorpos Monoclonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Ipilimumab/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Mutação , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/efeitos adversos , Antineoplásicos Imunológicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas/genética , Intervalo Livre de Doença , Feminino , Humanos , Ipilimumab/efeitos adversos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/genética , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Nivolumabe
7.
Eur J Cancer Care (Engl) ; 30(6): e13492, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34312918

RESUMO

OBJECTIVE: Lung cancer patients from ethnic minorities have poorer outcomes than their Caucasian counterparts. We compared lung cancer intervals between culturally and linguistically diverse (CALD) and Anglo-Australian patients to identify ethnic disparities. METHODS: This was a prospective, observational cohort study comprising a patient survey and reviews of patients' hospital and general practice records. Across three states, 577 (407 Anglo-Australian and 170 CALD) patients were recruited and their hospital records reviewed. The survey was returned by 189 (135 Anglo-Australian and 54 CALD) patients, and a review was completed by general practitioners (GPs) of 99 (76 Anglo-Australian and 23 CALD) patients. Survival and Cox regression analyses were conducted. RESULTS: CALD patients had longer hospital diagnostic interval [median 30 days, 95% confidence interval (CI) 26-34] than Anglo-Australian patients (median 17, 95% CI 14-20), p = 0.005, hazard ratio (HR) = 1.32 (95% CI 1.09-1.60). This difference persisted after relevant factors were taken into consideration, adjusted HR = 1.26 (95% CI 1.03-1.54, p = 0.022). CALD patients also reported longer prehospital intervals; however, these differences were not statistically significant. CONCLUSION: Target interventions need to be developed to address ethnic disparity in hospital diagnostic interval.


Assuntos
Etnicidade , Neoplasias Pulmonares , Austrália , Humanos , Estudos Prospectivos , População Branca
8.
Lancet Oncol ; 21(9): 1213-1223, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32888453

RESUMO

BACKGROUND: There is a strong unmet need to improve systemic therapy in mesothelioma. Chemotherapy with cisplatin and pemetrexed improves survival in malignant pleural mesothelioma, and immune checkpoint inhibitors are an emerging treatment in this disease. We aimed to evaluate the activity of durvalumab, an anti-PD-L1 antibody, given during and after first-line chemotherapy with cisplatin and pemetrexed in patients with advanced malignant pleural mesothelioma. METHODS: DREAM was a multicentre, single-arm, open-label, phase 2 trial done in nine hospitals in Australia. Eligible patients were aged 18 years or older and had histologically confirmed malignant pleural mesothelioma considered unsuitable for cancer-directed surgery, an Eastern Cooperative Oncology Group performance status of 0 or 1, and measurable disease as per the modified Response Evaluation Criteria in Solid Tumors version 1.0 (mRECIST) for mesothelioma that was previously untreated with systemic therapy. All histological subtypes were eligible. The first six participants were treated for two cycles in a safety run-in. All participants received cisplatin 75 mg/m2, pemetrexed 500 mg/m2, and durvalumab 1125 mg intravenously on day 1 of a 3-weekly schedule for a maximum of six cycles. Change from cisplatin to carboplatin with an area under the curve of 5 was permitted. Durvalumab was continued for a maximum of 12 months. The primary endpoint was progression-free survival at 6 months, measured according to mRECIST for malignant pleural mesothelioma and analysed in the intention-to-treat population. Safety analyses included all participants who receive at least one dose of any study drug. This study is registered with the Australia New Zealand Clinical Trials Registry, ACTRN12616001170415. FINDINGS: Between Dec 28, 2016, and Sept 27, 2017, 55 participants were enrolled. 54 patients were eligible and were followed up for a median of 28·2 months (IQR 26·5-30·2). 31 (57%; 95% CI 44-70) of 54 patients were alive and progression-free at 6 months. The most common grade 3-4 adverse events were neutropenia (seven [13%] patients), nausea (six [11%]), and anaemia (four [7%]). A total of 60 serious adverse events occurred in 29 participants, five of which were considered possibly related to durvalumab. Five patients died during the study treatment; none of these five deaths were attributed to study treatment. INTERPRETATION: The combination of durvalumab, cisplatin, and pemetrexed has promising activity and an acceptable safety profile that warrants further investigation in a randomised phase 3 trial. FUNDING: AstraZeneca.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Cisplatino/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Mesotelioma/tratamento farmacológico , Pemetrexede/administração & dosagem , Neoplasias Pleurais/tratamento farmacológico , Adolescente , Adulto , Idoso , Anticorpos Anti-Idiotípicos/administração & dosagem , Anticorpos Anti-Idiotípicos/efeitos adversos , Anticorpos Monoclonais/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Austrália/epidemiologia , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/genética , Cisplatino/efeitos adversos , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Masculino , Mesotelioma/genética , Mesotelioma/imunologia , Mesotelioma/patologia , Mesotelioma Maligno , Pessoa de Meia-Idade , Pemetrexede/efeitos adversos , Neoplasias Pleurais/genética , Neoplasias Pleurais/imunologia , Neoplasias Pleurais/patologia , Intervalo Livre de Progressão
9.
Mol Cancer ; 19(1): 16, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31987050

RESUMO

Since the publication of this work [1] and in response to a recent query that was brought to our attention in relation to the Western Blot in Figure 1(C) for NP2, protein lysates prepared around the same time as those presented in the manuscript in question, were run by SDS-PAGE under similar experimental conditions and probed using the same primary antibodies to NP1 and NP2 that were used originally.

10.
Br J Cancer ; 123(4): 591-603, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32439936

RESUMO

BACKGROUND: Non-small cell lung cancers (NSCLC) account for 85-90% of all lung cancers. As drug resistance critically impairs chemotherapy effectiveness, there is great need to identify new therapeutic targets. The aims of this study were to investigate the prognostic and therapeutic potential of the copper-metabolism-domain-protein, COMMD4, in NSCLC. METHODS: The expression of COMMD4 in NSCLC was investigated using bioinformatic analysis, immunoblotting of immortalised human bronchial epithelial (HBEC) and NSCLC cell lines, qRT-PCR and immunohistochemistry of tissue microarrays. COMMD4 function was additionally investigated in HBEC and NSCLC cells depleted of COMMD4, using small interfering RNA sequences. RESULTS: Bioinformatic analysis and in vitro analysis of COMMD4 transcripts showed that COMMD4 levels were upregulated in NSCLC and elevated COMMD4 was associated with poor prognosis in adenocarcinoma (ADC). Immunoblotting demonstrated that COMMD4 expression was upregulated in NSCLC cells and siRNA-depletion of COMMD4, decreased cell proliferation and reduced cell viability. Cell death was further enhanced after exposure to DNA damaging agents. COMMD4 depletion caused NSCLC cells to undergo mitotic catastrophe and apoptosis. CONCLUSIONS: Our data indicate that COMMD4 may function as a prognostic factor in ADC NSCLC. Additionally, COMMD4 is a potential therapeutic target for NSCLC, as its depletion induces cancer cell death.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Regulação para Cima , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Biologia Computacional , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Estadiamento de Neoplasias , Prognóstico , Análise de Sobrevida , Análise Serial de Tecidos
11.
Future Oncol ; 15(19): 2287-2302, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31066582

RESUMO

Nivolumab and ipilimumab, two therapeutic immune checkpoint inhibitor antibodies that block PD-1 and CTLA-4, respectively, have indications in cancer as single agents and in combination. In this Review, we examine the potential role of dual immune checkpoint inhibition with nivolumab plus ipilimumab in the management of patients with previously untreated advanced non-small-cell lung cancer, based on results from the Phase III CheckMate 227 study. Immunotherapies with indications in the first-line treatment of non-small-cell lung cancer include pembrolizumab alone and combined with chemotherapy, and atezolizumab combined with bevacizumab and chemotherapy. CheckMate 227 is the first Phase III study evaluating first-line chemotherapy-sparing combination immunotherapy and including tumor mutational burden as a biomarker for patient selection.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Antígeno CTLA-4/antagonistas & inibidores , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Terapia Combinada , Humanos , Imunoterapia , Ipilimumab/uso terapêutico , Nivolumabe/uso terapêutico , Receptor de Morte Celular Programada 1/antagonistas & inibidores
12.
Nucleic Acids Res ; 44(16): 7963-73, 2016 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-27387285

RESUMO

Single-stranded DNA binding proteins (SSBs) play an important role in DNA processing events such as replication, recombination and repair. Human single-stranded DNA binding protein 1 (hSSB1/NABP2/OBFC2B) contains a single oligosaccharide/oligonucleotide binding (OB) domain followed by a charged C-terminus and is structurally homologous to the SSB from the hyperthermophilic crenarchaeote Sulfolobus solfataricus Recent work has revealed that hSSB1 is critical to homologous recombination and numerous other important biological processes such as the regulation of telomeres, the maintenance of DNA replication forks and oxidative damage repair. Since the ability of hSSB1 to directly interact with single-stranded DNA (ssDNA) is paramount for all of these processes, understanding the molecular details of ssDNA recognition is essential. In this study, we have used solution-state nuclear magnetic resonance in combination with biophysical and functional experiments to structurally analyse ssDNA binding by hSSB1. We reveal that ssDNA recognition in solution is modulated by base-stacking of four key aromatic residues within the OB domain. This DNA binding mode differs significantly from the recently determined crystal structure of the SOSS1 complex containing hSSB1 and ssDNA. Our findings elucidate the detailed molecular mechanism in solution of ssDNA binding by hSSB1, a major player in the maintenance of genomic stability.


Assuntos
DNA de Cadeia Simples/química , DNA de Cadeia Simples/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Proteínas Mitocondriais/química , Proteínas Mitocondriais/metabolismo , Sequência de Aminoácidos , Aminoácidos Aromáticos/metabolismo , Análise Mutacional de DNA , Células HeLa , Humanos , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Ligação Proteica , Domínios Proteicos , Alinhamento de Sequência , Soluções
13.
Adv Exp Med Biol ; 1056: 123-135, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29754178

RESUMO

The role of extracellular vesicles (EV) in carcinogenesis has become the focus of much research. These microscopic messengers have been found to regulate immune system function, particularly in tumorigenesis, as well as conditioning future metastatic sites for the attachment and growth of tumor tissue. Through an interaction with a range of host tissues, EVs are able to generate a pro-tumor environment that is essential for tumorigenesis. These small nanovesicles are an ideal candidate for a non-invasive indicator of pathogenesis and/or disease progression as they can display individualized nucleic acid, protein, and lipid expression profiles that are often reflective of disease state, and can be easily detected in bodily fluids, even after extended cryo-storage. Furthermore, the ability of EVs to securely transport signaling molecules and localize to distant tissues suggests these particles may greatly improve the delivery of therapeutic treatments, particularly in cancer. In this chapter, we discuss the role of EV in the identification of new diagnostic and prognostic cancer biomarkers, as well as the development of novel EV-based cancer therapies.


Assuntos
Vesículas Extracelulares/fisiologia , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/genética , Neoplasias/patologia , Animais , Biomarcadores Tumorais , Vacinas Anticâncer/uso terapêutico , Comunicação Celular , Ensaios Clínicos como Assunto , Exossomos/genética , Exossomos/fisiologia , Exossomos/transplante , Vesículas Extracelulares/transplante , Terapia Genética/métodos , Humanos , Terapia de Alvo Molecular/métodos , Neoplasias/diagnóstico , Neoplasias/terapia , Prognóstico
14.
BMC Mol Biol ; 18(1): 13, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28506294

RESUMO

BACKGROUND: Maintenance of genome stability is critical in human cells. Mutations in or loss of genome stability pathways can lead to a number of pathologies including cancer. hSSB1 is a critical DNA repair protein functioning in the repair and signalling of stalled DNA replication forks, double strand DNA breaks and oxidised DNA lesions. The BLM helicase is central to the repair of both collapsed DNA replication forks and double strand DNA breaks by homologous recombination. RESULTS: In this study, we demonstrate that hSSB1 and BLM helicase form a complex in cells and the interaction is altered in response to ionising radiation (IR). BLM and hSSB1 also co-localised at nuclear foci following IR-induced double strand breaks and stalled replication forks. We show that hSSB1 depleted cells contain less BLM protein and that this deficiency is due to proteasome mediated degradation of BLM. Consequently, there is a defect in recruitment of BLM to chromatin in response to ionising radiation-induced DSBs and to hydroxyurea-induced stalled and collapsed replication forks. CONCLUSIONS: Our data highlights that BLM helicase and hSSB1 function in a dynamic complex in cells and that this complex is likely required for BLM protein stability and function.


Assuntos
RecQ Helicases/metabolismo , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Linhagem Celular Tumoral , Cromatina/genética , Cromatina/metabolismo , Dano ao DNA , Reparo do DNA , Replicação do DNA , Humanos , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica , Estabilidade Proteica , Proteólise , Estresse Fisiológico
15.
Cell Immunol ; 319: 35-42, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28735814

RESUMO

BACKGROUND: Trastuzumab is an anti-HER2 monoclonal antibody (mAb) therapy capable of antibody-dependent cell-mediated cytotoxicity (ADCC) and used in the treatment of HER2+ breast cancer. Through interactions with FcÆ´R+ immune cell subsets, trastuzumab functions as a passive immunotherapy. The EGFR/HER2-targeting tyrosine kinase inhibitor (TKI) lapatinib and the next generation TKIs afatinib and neratinib, can alter HER2 levels, potentially modulating the ADCC response to trastuzumab. Using LDH-release assays, we investigated the impact of antigen modulation, assay duration and peripheral blood mononuclear cell (PBMC) activity on trastuzumab-mediated ADCC in breast cancer models of maximal (SKBR3) and minimal (MCF-7) target antigen expression to determine if modulating the ADCC response to trastuzumab using TKIs may be a viable approach for enhancing tumor immune reactivity. METHODS: HER2 levels were determined in lapatinib, afatinib and neratinib-treated SKBR3 and MCF-7 using high content analysis (HCA). Trastuzumab-mediated ADCC was assessed following treatment with TKIs utilising a colorimetric LDH release-based protocol at 4 and 12h timepoints. PBMC activity was assessed against non-MHC-restricted K562 cells. A flow cytometry-based method (CFSE/7-AAD) was also used to measure trastuzumab-mediated ADCC in medium-treated SKBR3 and MCF-7. RESULTS: HER2 antigen levels were significantly altered by the three TKIs in both cell line models. The TKIs significantly reduced LDH levels directly in SKBR3 cells but not MCF-7. Lapatinib and neratinib augment trastuzumab-related ADCC in SKBR3 but the effect was not consistent with antigen expression levels and was dependent on volunteer PBMC activity (vs. K562). A 12h assay timepoint produced more consistent results. Trastuzumab-mediated ADCC (PBMC:target cell ratio of 10:1) was measured at 7.6±4.7% (T12) by LDH assay and 19±3.2 % (T12) using the flow cytometry-based method in the antigen-low model MCF-7. CONCLUSIONS: In the presence of effector cells with high cytotoxic capacity, TKIs have the ability to augment the passive immunotherapeutic potential of trastuzumab in SKBR3, a model of HER2+ breast cancer. ADCC levels detected by LDH release assays are extremely low in MCF-7; the flow cytometry-based CFSE/7-AAD method is more sensitive and consistent for the determination of ADCC in HER2-low models.


Assuntos
Antineoplásicos/farmacologia , Citotoxicidade Imunológica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Inibidores de Proteínas Quinases/farmacologia , Receptor ErbB-2/genética , Trastuzumab/farmacologia , Afatinib , Linhagem Celular Tumoral , Citotoxicidade Imunológica/genética , Interações Medicamentosas , Humanos , Células K562 , L-Lactato Desidrogenase/metabolismo , Lapatinib , Células MCF-7 , Quinazolinas/farmacologia , Quinolinas/farmacologia , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/metabolismo , Transdução de Sinais
16.
BMC Mol Biol ; 17(1): 24, 2016 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-27938330

RESUMO

BACKGROUND: Single-stranded DNA-binding proteins are essential cellular components required for the protection, metabolism and processing of single-stranded DNA. Human single-stranded DNA-binding protein 1 (hSSB1) is one such protein, with described roles in genome stability maintenance and transcriptional regulation. As yet, however, the mechanisms through which hSSB1 functions and the binding partners with which it interacts remain poorly understood. RESULTS: In this work, hSSB1 was immunoprecipitated from cell lysate samples that had been enriched for non-soluble nuclear proteins and those associating with hSSB1 identified by mass spectrometry. In doing so, 334 potential hSSB1-associating proteins were identified, with known roles in a range of distinct biological processes. Unexpectedly, whilst hSSB1 has largely been studied in a genome stability context, few other DNA repair or replication proteins were detected. By contrast, a large number of proteins were identified with roles in mRNA metabolism, reflecting a currently emerging area of hSSB1 study. In addition, numerous proteins were detected that comprise various chromatin-remodelling complexes. CONCLUSIONS: These findings provide new insight into the binding partners of hSSB1 and will likely function as a platform for future research.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas Mitocondriais/metabolismo , RNA Mensageiro/metabolismo , Montagem e Desmontagem da Cromatina , Proteínas de Ligação a DNA/isolamento & purificação , Humanos , Imunoprecipitação , Proteínas Mitocondriais/isolamento & purificação , Ligação Proteica
17.
BMC Mol Biol ; 17(1): 19, 2016 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-27553022

RESUMO

Nucleophosmin (NPM1) is a critical cellular protein that has been implicated in a number of pathways including mRNA transport, chromatin remodeling, apoptosis and genome stability. NPM1 function is a critical requirement for normal cellular biology as is underlined in cancer where NPM1 is commonly overexpressed, mutated, rearranged and sporadically deleted. Consistent with a multifunctional role within the cell, NPM1 can function not only as a proto-oncogene but also as a tumor suppressor. The aim of this review is to look at the less well-described role of NPM1 in the DNA repair pathways as well as the role of NPM1 in the regulation of apoptosis and its mutation in cancers.


Assuntos
Reparo do DNA , Mutação , Neoplasias/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Animais , Apoptose , Evolução Molecular , Instabilidade Genômica , Humanos , Modelos Moleculares , Neoplasias/metabolismo , Proteínas Nucleares/química , Nucleofosmina , Conformação Proteica , Proto-Oncogene Mas
19.
N Engl J Med ; 368(25): 2385-94, 2013 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-23724913

RESUMO

BACKGROUND: In single-group studies, chromosomal rearrangements of the anaplastic lymphoma kinase gene (ALK) have been associated with marked clinical responses to crizotinib, an oral tyrosine kinase inhibitor targeting ALK. Whether crizotinib is superior to standard chemotherapy with respect to efficacy is unknown. METHODS: We conducted a phase 3, open-label trial comparing crizotinib with chemotherapy in 347 patients with locally advanced or metastatic ALK-positive lung cancer who had received one prior platinum-based regimen. Patients were randomly assigned to receive oral treatment with crizotinib (250 mg) twice daily or intravenous chemotherapy with either pemetrexed (500 mg per square meter of body-surface area) or docetaxel (75 mg per square meter) every 3 weeks. Patients in the chemotherapy group who had disease progression were permitted to cross over to crizotinib as part of a separate study. The primary end point was progression-free survival. RESULTS: The median progression-free survival was 7.7 months in the crizotinib group and 3.0 months in the chemotherapy group (hazard ratio for progression or death with crizotinib, 0.49; 95% confidence interval [CI], 0.37 to 0.64; P<0.001). The response rates were 65% (95% CI, 58 to 72) with crizotinib, as compared with 20% (95% CI, 14 to 26) with chemotherapy (P<0.001). An interim analysis of overall survival showed no significant improvement with crizotinib as compared with chemotherapy (hazard ratio for death in the crizotinib group, 1.02; 95% CI, 0.68 to 1.54; P=0.54). Common adverse events associated with crizotinib were visual disorder, gastrointestinal side effects, and elevated liver aminotransferase levels, whereas common adverse events with chemotherapy were fatigue, alopecia, and dyspnea. Patients reported greater reductions in symptoms of lung cancer and greater improvement in global quality of life with crizotinib than with chemotherapy. CONCLUSIONS: Crizotinib is superior to standard chemotherapy in patients with previously treated, advanced non-small-cell lung cancer with ALK rearrangement. (Funded by Pfizer; ClinicalTrials.gov number, NCT00932893.).


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Pirazóis/uso terapêutico , Piridinas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Crizotinibe , Intervalo Livre de Doença , Docetaxel , Feminino , Glutamatos/efeitos adversos , Glutamatos/uso terapêutico , Guanina/efeitos adversos , Guanina/análogos & derivados , Guanina/uso terapêutico , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Pemetrexede , Inibidores de Proteínas Quinases/efeitos adversos , Pirazóis/efeitos adversos , Piridinas/efeitos adversos , Qualidade de Vida , Taxoides/efeitos adversos , Taxoides/uso terapêutico , Adulto Jovem
20.
BMC Cancer ; 16: 707, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27586635

RESUMO

BACKGROUND: Baicalein is a widely used Chinese herbal medicine derived from Scutellaria baicalenesis, which has been traditionally used as anti-inflammatory and anti-cancer therapy. In this study we examined the anti-tumour pathways activated following baicalein treatment in non-small cell lung cancer (NSCLC), both in-vitro and in-vivo. METHODS: The effect of baicalein treatment on H-460 cells in-vitro was assessed using both BrdU assay (cell proliferation) and High Content Screening (multi-parameter apoptosis assay). A xenograft nude mouse model was subsequently established using these cells and the effect of baicalein on tumour growth and survival assessed in-vivo. Tumours were harvested from these mice and histological tissue analysis carried out. VEGF, 12-lipoxygenase and microvessel density (CD-31) were assessed by immunohistochemistry (IHC), while H and E staining was carried out to assess mitotic index. Gene expression profiling was carried out on corresponding RNA samples using Human Cancer Pathway Finder Arrays and qRT-PCR, with further gene expression analysis carried out using qRT-PCR. RESULTS: Baicalein significantly decreased lung cancer proliferation in H-460 cells in a dose dependent manner. At the functional level, a dose-dependent induction in apoptosis associated with decreased cellular f-actin content, an increase in nuclear condensation and an increase in mitochondrial mass potential was observed. Orthotopic treatment of experimental H-460 tumours in athymic nude mice with baicalein significantly (p < 0.05) reduced tumour growth and prolonged survival. Histological analysis of resulting tumour xenografts demonstrated reduced expression of both 12-lipoxygenase and VEGF proteins in baicalein-treated tumours, relative to untreated. A significant (p < 0.01) reduction in both mitotic index and micro-vessel density was observed following baicalein treatment. Gene expression profiling revealed a reduction (p < 0.01) in both VEGF and FGFR-2 following baicalein treatment, with a corresponding increase (p < 0.001) in RB-1. CONCLUSION: This study is the first to demonstrate efficacy of baicalein both in-vitro and in-vivo in NSCLC. These effects may be mediated in part through a reduction in both cell cycle progression and angiogenesis. At the molecular level, alterations in expression of VEGF, FGFR-2, and RB-1 have been implicated, suggesting a molecular mechanism underlying this in-vivo effect.


Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/patologia , Flavanonas/farmacologia , Neoplasias Pulmonares/patologia , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Reação em Cadeia da Polimerase , Transcriptoma/efeitos dos fármacos , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
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