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1.
Chemotherapy ; : 1-7, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38679017

RESUMO

INTRODUCTION: As tumour response rates are increasingly demonstrated in early-phase cancer trials (EPCT), optimal patient selection and accurate prognostication are paramount. Hammersmith Score (HS), a simple prognostic index derived on routine biochemical measures (albumin <35 g/L, lactate dehydrogenase >450 IU/L, sodium <135 mmol/L), is a validated predictor of response and survival in EPCT participants. HS has not been validated in the cancer immunotherapy era. METHODS: We retrospectively analysed characteristics and outcomes of unselected referrals to our early-phase unit (12/2019-12/2022). Independent predictors for overall survival (OS) were identified from univariable and multivariable models. HS was calculated for 66 eligible trial participants and compared with the Royal Marsden Score (RMS) to predict OS. Multivariable logistic regression and C-index was used to compare predictive ability of prognostic models. RESULTS: Of 212 referrals, 147 patients were screened and 82 patients treated in EPCT. Prognostic stratification by HS identifies significant difference in median OS, and HS was confirmed as a multivariable predictor for OS (HR: HS 1 vs. 0 2.51, 95% CI: 1.01-6.24, p = 0.049; HS 2/3 vs. 0: 10.32, 95% CI: 2.15-49.62, p = 0.004; C-index 0.771) with superior multivariable predictive ability than RMS (HR: RMS 2 vs. 0/1 5.46, 95% CI: 1.12-26.57, p = 0.036; RMS 3 vs. 0/1 6.83, 95% CI: 1.15-40.53, p < 0.001; C-index 0.743). CONCLUSIONS: HS is a validated prognostic index for patients with advanced cancer treated in the context of modern EPCTs, independent of tumour burden. HS is a simple, inexpensive prognostic tool to optimise referral for EPCT.

2.
Int J Gynecol Cancer ; 33(8): 1253-1259, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37072323

RESUMO

OBJECTIVE: Olaparib plus bevacizumab maintenance therapy improves survival outcomes in women with newly diagnosed, advanced, high-grade ovarian cancer with a deficiency in homologous recombination. We report data from the first year of routine homologous recombination deficiency testing in the National Health Service (NHS) in England, Wales, and Northern Ireland between April 2021 and April 2022. METHODS: The Myriad myChoice companion diagnostic was used to test DNA extracted from formalin-fixed, paraffin-embedded tumor tissue in women with newly diagnosed International Federation of Gynecology and Obstetrics (FIGO) stage III/IV high-grade epithelial ovarian, fallopian tube, or primary peritoneal cancer. Tumors with homologous recombination deficiency were those with a BRCA1/2 mutation and/or a Genomic Instability Score (GIS) ≥42. Testing was coordinated by the NHS Genomic Laboratory Hub network. RESULTS: The myChoice assay was performed on 2829 tumors. Of these, 2474 (87%) and 2178 (77%) successfully underwent BRCA1/2 and GIS testing, respectively. All complete and partial assay failures occurred due to low tumor cellularity and/or low tumor DNA yield. 385 tumors (16%) contained a BRCA1/2 mutation and 814 (37%) had a GIS ≥42. Tumors with a GIS ≥42 were more likely to be BRCA1/2 wild-type (n=510) than BRCA1/2 mutant (n=304). The distribution of GIS was bimodal, with BRCA1/2 mutant tumors having a higher mean score than BRCA1/2 wild-type tumors (61 vs 33, respectively, χ2 test p<0.0001). CONCLUSION: This is the largest real-world evaluation of homologous recombination deficiency testing in newly diagnosed FIGO stage III/IV high-grade epithelial ovarian, fallopian tube, or primary peritoneal cancer. It is important to select tumor tissue with adequate tumor content and quality to reduce the risk of assay failure. The rapid uptake of testing across England, Wales, and Northern Ireland demonstrates the power of centralized NHS funding, center specialization, and the NHS Genomic Laboratory Hub network.


Assuntos
Proteína BRCA1 , Neoplasias Ovarianas , Feminino , Humanos , Carcinoma Epitelial do Ovário/genética , Proteína BRCA1/genética , Neoplasias Ovarianas/patologia , Medicina Estatal , Proteína BRCA2/genética , Instabilidade Genômica , Recombinação Homóloga , Mutação
3.
Noncoding RNA ; 8(4)2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-36005826

RESUMO

As research uncovers the underpinnings of cancer biology, new targeted therapies have been developed. Many of these therapies are small molecules, such as kinase inhibitors, that target specific proteins; however, only 1% of the genome encodes for proteins and only a subset of these proteins has 'druggable' active binding sites. In recent decades, RNA therapeutics have gained popularity due to their ability to affect targets that small molecules cannot. Additionally, they can be manufactured more rapidly and cost-effectively than small molecules or recombinant proteins. RNA therapeutics can be synthesised chemically and altered quickly, which can enable a more personalised approach to cancer treatment. Even though a wide range of RNA therapeutics are being developed for various indications in the oncology setting, none has reached the clinic to date. One of the main reasons for this is attributed to the lack of safe and effective delivery systems for this type of therapeutic. This review focuses on current strategies to overcome these challenges and enable the clinical utility of these novel therapeutic agents in the cancer clinic.

4.
Clin Cancer Res ; 28(13): 2911-2922, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35398881

RESUMO

PURPOSE: Ovarian high-grade serous carcinoma (HGSC) is usually diagnosed at late stage. We investigated whether late-stage HGSC has unique genomic characteristics consistent with acquisition of evolutionary advantage compared with early-stage tumors. EXPERIMENTAL DESIGN: We performed targeted next-generation sequencing and shallow whole-genome sequencing (sWGS) on pretreatment samples from 43 patients with FIGO stage I-IIA HGSC to investigate somatic mutations and copy-number (CN) alterations (SCNA). We compared results to pretreatment samples from 52 patients with stage IIIC/IV HGSC from the BriTROC-1 study. RESULTS: Age of diagnosis did not differ between early-stage and late-stage patients (median 61.3 years vs. 62.3 years, respectively). TP53 mutations were near-universal in both cohorts (89% early-stage, 100% late-stage), and there were no significant differences in the rates of other somatic mutations, including BRCA1 and BRCA2. We also did not observe cohort-specific focal SCNA that could explain biological behavior. However, ploidy was higher in late-stage (median, 3.0) than early-stage (median, 1.9) samples. CN signature exposures were significantly different between cohorts, with greater relative signature 3 exposure in early-stage and greater signature 4 in late-stage. Unsupervised clustering based on CN signatures identified three clusters that were prognostic. CONCLUSIONS: Early-stage and late-stage HGSCs have highly similar patterns of mutation and focal SCNA. However, CN signature analysis showed that late-stage disease has distinct signature exposures consistent with whole-genome duplication. Further analyses will be required to ascertain whether these differences reflect genuine biological differences between early-stage and late-stage or simply time-related markers of evolutionary fitness. See related commentary by Yang et al., p. 2730.


Assuntos
Neoplasias Ovarianas , Carcinoma Epitelial do Ovário , Feminino , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Pessoa de Meia-Idade , Mutação , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia
5.
Ther Adv Med Oncol ; 12: 1758835920921980, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32523631

RESUMO

The use of targeted therapeutics known as poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitors in the management of ovarian cancer is currently transforming clinical practice. The PARP inhibitor rucaparib is indicated in the UK, European Union and the United States for use in the treatment and maintenance settings for patients with relapsed ovarian cancer. Here, we discuss some of the real-world challenges and side effects that we have encountered while prescribing rucaparib, and we provide practical guidance on how the individual members of our multidisciplinary team (MDT), including a clinician, chemotherapy nurse practitioner, and clinical pharmacist, collaborate to manage these side effects. If recognized early, the side effects experienced by patients during rucaparib therapy, which include fatigue, nausea and vomiting, liver enzyme elevations, and anemia, can be easily managed. For example, providing patients with prophylactic antiemetics can help them avoid nausea, and early detection of decreases in hemoglobin levels allows for proactive interventions to alleviate anemia. The MDT should work together with the patient to identify potential side effects early and manage them effectively. The aim of this proactive approach is to maintain patients on rucaparib for optimal clinical benefit, while minimizing the potential negative impact of side effects on patient quality of life.

6.
Sci Rep ; 10(1): 3390, 2020 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-32098980

RESUMO

Although guidelines recommend BRCA testing for all women with non-mucinous epithelial ovarian cancer, there is significant variability in access to testing across the UK. A germline BRCA mutation (BRCAm) in ovarian cancer patients provides prognostic and predictive information and influences clinical management, such as the use of PARP inhibitors, which have demonstrated a progression-free survival benefit in the BRCAm cohort. Additionally, the finding of a BRCAm has significant implications for patients and their families in terms of cancer risk and prevention. We studied the impact of a newly-formed, oncologist-led 'mainstreaming' germline BRCA testing pathway in 255 ovarian cancer patients at Imperial College NHS Trust. Prior to the establishment of 'mainstreaming', uptake of germline BRCA testing was 14% with a mean turnaround time of 148.2 calendar days. The 'mainstreaming' approach led to a 95% uptake of germline BRCA testing and a mean turnaround time of 20.6 days. Thirty-four (13.33%) BRCAm patients were identified. At the time of data collection nine BRCAm patients had received a PARP inhibitor off-trial, three had entered a PARP inhibitor trial and 5 were receiving platinum-based chemotherapy with a plan to receive PARP inhibitor maintenance. This study provides further evidence of the impact of oncologist-led 'mainstreaming' programs.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias Ovarianas/tratamento farmacológico , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína BRCA1/metabolismo , Proteína BRCA2/metabolismo , Tomada de Decisões , Feminino , Mutação em Linhagem Germinativa , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/diagnóstico , Platina/uso terapêutico , Prognóstico , Reino Unido
7.
Cancer Res ; 76(20): 6118-6129, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27530326

RESUMO

There is a need for transplantable murine models of ovarian high-grade serous carcinoma (HGSC) with regard to mutations in the human disease to assist investigations of the relationships between tumor genotype, chemotherapy response, and immune microenvironment. In addressing this need, we performed whole-exome sequencing of ID8, the most widely used transplantable model of ovarian cancer, covering 194,000 exomes at a mean depth of 400× with 90% exons sequenced >50×. We found no functional mutations in genes characteristic of HGSC (Trp53, Brca1, Brca2, Nf1, and Rb1), and p53 remained transcriptionally active. Homologous recombination in ID8 remained intact in functional assays. Further, we found no mutations typical of clear cell carcinoma (Arid1a, Pik3ca), low-grade serous carcinoma (Braf), endometrioid (Ctnnb1), or mucinous (Kras) carcinomas. Using CRISPR/Cas9 gene editing, we modeled HGSC by generating novel ID8 derivatives that harbored single (Trp53-/-) or double (Trp53-/-;Brca2-/-) suppressor gene deletions. In these mutants, loss of p53 alone was sufficient to increase the growth rate of orthotopic tumors with significant effects observed on the immune microenvironment. Specifically, p53 loss increased expression of the myeloid attractant CCL2 and promoted the infiltration of immunosuppressive myeloid cell populations into primary tumors and their ascites. In Trp53-/-;Brca2-/- mutant cells, we documented a relative increase in sensitivity to the PARP inhibitor rucaparib and slower orthotopic tumor growth compared with Trp53-/- cells, with an appearance of intratumoral tertiary lymphoid structures rich in CD3+ T cells. This work validates new CRISPR-generated models of HGSC to investigate its biology and promote mechanism-based therapeutics discovery. Cancer Res; 76(20); 6118-29. ©2016 AACR.


Assuntos
Proteína BRCA2/fisiologia , Sistemas CRISPR-Cas/fisiologia , Cistadenocarcinoma Seroso/etiologia , Modelos Animais de Doenças , Neoplasias Ovarianas/etiologia , Proteína Supressora de Tumor p53/fisiologia , Animais , Proteína BRCA2/genética , Linhagem Celular Tumoral , Cistadenocarcinoma Seroso/tratamento farmacológico , Exoma , Feminino , Edição de Genes , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Microambiente Tumoral , Proteína Supressora de Tumor p53/genética
8.
Mol Cancer Res ; 14(1): 44-55, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26452665

RESUMO

UNLABELLED: Homologous recombination (HR) function is critically important in high-grade serous ovarian cancer (HGSOC). HGSOC with intact HR has a worse prognosis and is less likely to respond to platinum chemotherapy and PARP inhibitors. Oncolytic adenovirus, a novel therapy for human malignancies, stimulates a potent DNA damage response that influences overall antitumor activity. Here, the importance of HR was investigated by determining the efficacy of adenovirus type 5 (Ad5) vectors in ovarian cancer. Using matched BRCA2-mutant and wild-type HGSOC cells, it was demonstrated that intact HR function promotes viral DNA replication and augments overall efficacy, without influencing viral DNA processing. These data were confirmed in a wider panel of HR competent and defective ovarian cancer lines. Mechanistically, both BRCA2 and RAD51 localize to viral replication centers within the infected cell nucleus and that RAD51 localization occurs independently of BRCA2. In addition, a direct interaction was identified between RAD51 and adenovirus E2 DNA binding protein. Finally, using functional assays of HR competence, despite inducing degradation of MRE11, Ad5 infection does not alter cellular ability to repair DNA double-strand break damage via HR. These data reveal that Ad5 redistributes critical HR components to viral replication centers and enhances cytotoxicity. IMPLICATIONS: Oncolytic adenoviral therapy may be most clinically relevant in tumors with intact HR function.


Assuntos
Adenoviridae/fisiologia , Proteína BRCA2/metabolismo , Recombinação Homóloga , Neoplasias Ovarianas/metabolismo , Rad51 Recombinase/metabolismo , Adenoviridae/genética , Proteínas E2 de Adenovirus/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cisplatino/farmacologia , Feminino , Vetores Genéticos/farmacologia , Humanos , Terapia Viral Oncolítica , Replicação Viral
9.
Cancer Res ; 75(14): 2811-21, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25977332

RESUMO

Adenoviruses have been clinically tested as anticancer therapies but their utility has been severely limited by rapid, systemic cytokine release and consequent inflammatory toxicity. Here, we describe a new approach to tackling these dangerous side effects. Using human ovarian cancer cell lines as well as malignant epithelial cells harvested from the ascites of women with ovarian cancer, we show that tumor cells do not produce cytokines in the first 24 hours following in vitro infection with the oncolytic adenovirus dl922-947. In contrast, dl922-947 does induce inflammatory cytokines at early time points following intraperitoneal delivery in mice with human ovarian cancer intraperitoneal xenografts. In these animals, cytokines originate predominantly in murine tissues, especially in macrophage-rich organs such as the spleen. We use a nonreplicating adenovirus to confirm that early cytokine production is independent of adenoviral replication. Using ß3 integrin knockout mice injected intraperitoneally with dl922-947 and ß3 null murine peritoneal macrophages, we confirm a role for macrophage cell surface ß3 integrin in this dl922-947-induced inflammation. We present new evidence that co-administration of a cyclic RGD-mimetic-specific inhibitor of ß3 integrin significantly attenuates the cytokine release and inflammatory hepatic toxicity induced by dl922-947 in an intraperitoneal murine model of ovarian cancer. Importantly, we find no evidence that ß3 inhibition compromises viral infectivity and oncolysis in vitro or anticancer efficacy in vivo. By enabling safe, systemic delivery of replicating adenoviruses, this novel approach could have a major impact on the future development of these effective anticancer agents.


Assuntos
Adenoviridae/imunologia , Anti-Inflamatórios/farmacologia , Inflamação/prevenção & controle , Integrina beta3/metabolismo , Terapia Viral Oncolítica/efeitos adversos , Vírus Oncolíticos/imunologia , Neoplasias Ovarianas/terapia , Peptídeos Cíclicos/farmacologia , Adenoviridae/efeitos dos fármacos , Animais , Anti-Inflamatórios/uso terapêutico , Antineoplásicos/imunologia , Antineoplásicos/uso terapêutico , Células Cultivadas , Terapia Combinada , Feminino , Humanos , Integrina beta3/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Nus , Vírus Oncolíticos/efeitos dos fármacos , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/patologia , Peptídeos Cíclicos/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Mol Oncol ; 9(4): 791-805, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25560085

RESUMO

Resistance to paclitaxel chemotherapy frequently develops in ovarian cancer. Oncolytic adenoviruses are a novel therapy for human malignancies that are being evaluated in early phase trials. However, there are no reliable predictive biomarkers for oncolytic adenovirus activity in ovarian cancer. We investigated the link between paclitaxel resistance and oncolytic adenovirus activity using established ovarian cancer cell line models, xenografts with de novo paclitaxel resistance and tumour samples from two separate trials. The activity of multiple Ad5 vectors, including dl922-947 (E1A CR2-deleted), dl1520 (E1B-55K deleted) and Ad5 WT, was significantly increased in paclitaxel resistant ovarian cancer in vitro and in vivo. This was associated with greater infectivity resulting from increased expression of the primary receptor for Ad5, CAR (coxsackie adenovirus receptor). This, in turn, resulted from increased CAR transcription secondary to histone modification in resistant cells. There was increased CAR expression in intraperitoneal tumours with de novo paclitaxel resistance and in tumours from patients with clinical resistance to paclitaxel. Increased CAR expression did not cause paclitaxel resistance, but did increase inflammatory cytokine expression. Finally, we identified dysregulated cell cycle control as a second mechanism of increased adenovirus efficacy in paclitaxel-resistant ovarian cancer. Ad11 and Ad35, both group B adenoviruses that utilise non-CAR receptors to infect cells, are also significantly more effective in paclitaxel-resistant ovarian cell models. Inhibition of CDK4/6 using PD-0332991 was able both to reverse paclitaxel resistance and reduce adenovirus efficacy. Thus, paclitaxel resistance increases oncolytic adenovirus efficacy via at least two separate mechanisms - if validated further, this information could have future clinical utility to aid patient selection for clinical trials.


Assuntos
Adenoviridae/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Vírus Oncolíticos/metabolismo , Paclitaxel/farmacologia , Regulação para Cima/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Citocinas/metabolismo , Feminino , Histonas/metabolismo , Humanos , Mediadores da Inflamação/metabolismo , Camundongos Nus , Neoplasias Ovarianas/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Acta Oncol ; 52(5): 987-93, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22943385

RESUMO

OBJECTIVE: Metastatic seminoma is a highly curable disease. Standard treatment comprises of combination chemotherapy. The short- and long-term toxicities of this treatment are increasingly recognised and the possibility of over treatment in such a curable disease should be considered. We have therefore assessed the use of single agent carboplatin at a dose of AUC 10 in patients with good prognosis metastatic seminoma. MATERIALS AND METHODS: Patients with good prognosis metastatic seminoma treated with carboplatin (AUC 10) were identified at our institution and affiliated institutions. Treatment was three weekly for a total of three or four cycles. Outcome and toxicities were analysed. RESULTS: With a median follow-up of 36 months, 61 patients in total were treated with carboplatin AUC 10, all good prognosis by the IGCCCG criteria. Forty-eight percent had stage IIA/IIB disease and 52% had greater than stage IIB disease. Thirty-one patients (51%) had a complete response following treatment. Three-year survival was 96.3% with a three-year progression free survival of 93.2%. The main treatment toxicity was haematological with 46% having grade 3, 24% having grade 4 neutropenia and 54% experiencing grade 3/4 thrombocytopenia. There were no treatment related deaths. CONCLUSION: Single agent carboplatin at a dose of AUC 10 is an effective treatment for good prognosis metastatic seminoma. The outcome compares favourably to previously published outcomes of combination chemotherapy. Although haematological toxicity is a concern, single agent carboplatin treatment for good prognosis metastatic seminoma could be considered a treatment option and is associated with less toxicity than combination regimens currently used.


Assuntos
Antineoplásicos/uso terapêutico , Carboplatina/uso terapêutico , Seminoma/tratamento farmacológico , Neoplasias Testiculares/tratamento farmacológico , Adulto , Idoso , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neutropenia/induzido quimicamente , Estudos Retrospectivos , Seminoma/patologia , Neoplasias Testiculares/patologia , Trombocitopenia/induzido quimicamente , Resultado do Tratamento , Adulto Jovem
12.
Mol Ther ; 20(9): 1676-88, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22735379

RESUMO

Adaptive immune responses may be vital in the overall efficacy of oncolytic viruses in human malignancies. However, immune responses to oncolytic adenoviruses are poorly understood because these viruses lack activity in murine cells, which precludes evaluation in immunocompetent murine cancer models. We have evaluated human adenovirus activity in murine cells. We show that a panel of murine carcinoma cells, including CMT64, MOVCAR7, and MOSEC/ID8, can readily be infected with human adenovirus. These cells also support viral gene transcription, messenger RNA (mRNA) processing, and genome replication. However, there is a profound failure of adenovirus protein synthesis, especially late structural proteins, both in vitro and in vivo, with reduced loading of late mRNA onto ribosomes. Our data also show that in trans expression of the nonstructural late protein L4-100K increases both the amount of viral mRNA on ribosomes and the synthesis of late proteins, accompanied by reduced phosphorylation of eIF2α and improved anticancer efficacy. These results suggest that murine models that support human adenovirus replication could be generated, thus allowing evaluation of human adenoviruses in immunocompetent mice.


Assuntos
Adenovírus Humanos/genética , Vírus Oncolíticos/genética , Neoplasias Ovarianas/terapia , Biossíntese de Proteínas , RNA Viral/metabolismo , Proteínas não Estruturais Virais/genética , Imunidade Adaptativa , Adenovírus Humanos/imunologia , Animais , Linhagem Celular Tumoral , Fator de Iniciação 2 em Eucariotos/genética , Fator de Iniciação 2 em Eucariotos/metabolismo , Feminino , Expressão Gênica , Humanos , Camundongos , Vírus Oncolíticos/imunologia , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/patologia , Ovário/efeitos dos fármacos , Ovário/imunologia , Ovário/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Viral/genética , Ribossomos/genética , Ribossomos/metabolismo , Especificidade da Espécie , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/genética
13.
J Clin Invest ; 121(4): 1283-97, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21383502

RESUMO

Oncolytic adenoviruses replicate selectively within and lyse malignant cells. As such, they are being developed as anticancer therapeutics. However, the sensitivity of ovarian cancers to adenovirus cytotoxicity varies greatly, even in cells of similar infectivity. Using both the adenovirus E1A-CR2 deletion mutant dl922-947 and WT adenovirus serotype 5 in a panel of human ovarian cancer cell lines that cover a 3-log range of sensitivity, we observed profound overreplication of genomic DNA only in highly sensitive cell lines. This was associated with the presence of extensive genomic DNA damage. Inhibition of ataxia telangiectasia and Rad3-related checkpoint kinase 1 (ATR-Chk1), but not ataxia telangiectasia mutated (ATM), promoted genomic DNA damage and overreplication in resistant and partially sensitive cells. This was accompanied by increased adenovirus cytotoxicity both in vitro and in vivo in tumor-bearing mice. We also demonstrated that Cdc25A was upregulated in highly sensitive ovarian cancer cell lines after adenovirus infection and was stabilized after loss of Chk1 activity. Knockdown of Cdc25A inhibited virus-induced DNA damage in highly sensitive cells and blocked the effects of Chk1 inhibition in resistant cells. Finally, inhibition of Chk1 decreased homologous recombination repair of virus-induced genomic DNA double-strand breaks. Thus, virus-induced host cell DNA damage signaling and repair are key determinants of oncolytic adenoviral activity, and promoting unscheduled DNA synthesis and/or impeding homologous recombination repair could potentiate the effects of oncolytic adenoviruses in the treatment of ovarian cancer.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Dano ao DNA , Terapia Viral Oncolítica , Vírus Oncolíticos/genética , Vírus Oncolíticos/fisiologia , Neoplasias Ovarianas/terapia , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Proteínas Mutadas de Ataxia Telangiectasia , Linhagem Celular Tumoral , Quinase 1 do Ponto de Checagem , Reparo do DNA , Replicação do DNA , Feminino , Humanos , Camundongos , Camundongos Nus , Mutação , Transplante de Neoplasias , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Transdução de Sinais , Transplante Heterólogo , Fosfatases cdc25/metabolismo
14.
Br Med Bull ; 96: 111-29, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20870669

RESUMO

Recently there have been significant advances in rational drug design for the treatment of breast cancer, especially in the area of targeted drug therapy. These include drugs which target the HER2 receptor and angiogenesis and the novel class of drug the PARP inhibitors. Some of these agents, for example, trastuzumab used in the treatment of HER2 positive breast cancer are already established as the standard of care. However, the duration of adjuvant trastuzumab, whether to continue it beyond progression in metastatic disease and the mechanism for developing trastuzumab resistance, remain to be determined. There is also much still to be learnt regarding other targeted therapies; the efficacy of different agents, the optimal duration of use and combination of therapies. Many of these agents are already in clinical trials, the results of which are likely to change clinical practice.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Desenho de Fármacos , Inibidores da Angiogênese/uso terapêutico , Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Feminino , Humanos , Poli Adenosina Difosfato Ribose/antagonistas & inibidores , Receptor ErbB-2/antagonistas & inibidores
15.
Diabetes ; 51(12): 3412-9, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12453894

RESUMO

The hypothalamic circuits controlling food intake and body weight receive and integrate information from circulating satiety signals such as leptin and insulin and also from ghrelin, the only known circulating hormone that stimulates appetite following systemic injection. Activation of arcuate neurons by ghrelin and ghrelin mimetics (the growth hormone secretagogues) is augmented in 48-h-fasted rats compared with fed rats, as reflected by a greater number of cells expressing Fos protein in response to administration of the same maximally effective dose. Here we sought to determine whether this increased responsiveness in fasting might reflect or be influenced by low levels of circulating satiety factors such as leptin or insulin. Chronic central infusion of insulin or leptin during a 48-h fast suppressed the threefold increase in the Fos response to intravenous injection of a maximally effective dose of growth hormone-releasing peptide (GHRP)-6, a synthetic growth hormone secretagogue. This appears to be a direct central action of insulin and leptin because the marked decrease in plasma levels of insulin, leptin, and glucose during fasting were unaffected by central administration of either hormone. Furthermore, the GHRP-6-induced Fos response was twofold greater in obese leptin- and insulin-resistant Zucker rats compared with lean controls. These data provide evidence that the ghrelin-sensitive circuits in the hypothalamus are dynamically regulated by central insulin and leptin action.


Assuntos
Núcleo Arqueado do Hipotálamo/fisiologia , Insulina/farmacologia , Leptina/farmacologia , Oligopeptídeos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Animais , Glicemia/análise , Esquema de Medicação , Jejum/fisiologia , Injeções Intraventriculares , Insulina/efeitos adversos , Insulina/sangue , Leptina/efeitos adversos , Leptina/sangue , Masculino , Oligopeptídeos/efeitos adversos , Concentração Osmolar , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Wistar , Ratos Zucker/metabolismo , Valores de Referência
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