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1.
Br J Cancer ; 129(11): 1829-1840, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37777579

RESUMO

BACKGROUND: High-grade gliomas are primary brain cancers with unacceptably low and persistent survival rates of 10-16 months for WHO grade 4 gliomas over the last 40 years, despite surgical resection and DNA-damaging chemo-radiotherapy. More recently, tumour-treating fields therapy (TTFields) has demonstrated modest survival benefit and been clinically approved in several countries. TTFields is thought to mediate anti-cancer activity by primarily disrupting mitosis. However, recent data suggest that TTFields may also attenuate DNA damage repair and replication fork dynamics, providing a potential platform for therapeutic combinations incorporating standard-of-care treatments and targeted DNA damage response inhibitors (DDRi). METHODS: We have used patient-derived, typically resistant, glioma stem-like cells (GSCs) in combination with the previously validated preclinical Inovitro™ TTFields system together with a number of therapeutic DDRi. RESULTS: We show that TTFields robustly activates PARP- and ATR-mediated DNA repair (including PARylation and CHK1 phosphorylation, respectively), whilst combining TTFields with PARP1 or ATR inhibitor treatment leads to significantly reduced clonogenic survival. The potency of each of these strategies is further enhanced by radiation treatment, leading to increased amounts of DNA damage with profound delay in DNA damage resolution. CONCLUSION: To our knowledge, our findings represent the first report of TTFields applied with clinically approved or in-trial DDRi in GSC models and provides a basis for translational studies toward multimodal DDRi/TTFields-based therapeutic strategies for patients with these currently incurable tumours.


Assuntos
Glioma , Humanos , Glioma/patologia , Reparo do DNA , Dano ao DNA , Mitose
2.
Nucleic Acids Res ; 44(18): 8772-8785, 2016 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-27382066

RESUMO

Cyclin-dependent kinases (CDKs) coordinate cell cycle checkpoints with DNA repair mechanisms that together maintain genome stability. However, the myriad mechanisms that can give rise to genome instability are still to be fully elucidated. Here, we identify CDK18 (PCTAIRE 3) as a novel regulator of genome stability, and show that depletion of CDK18 causes an increase in endogenous DNA damage and chromosomal abnormalities. CDK18-depleted cells accumulate in early S-phase, exhibiting retarded replication fork kinetics and reduced ATR kinase signaling in response to replication stress. Mechanistically, CDK18 interacts with RAD9, RAD17 and TOPBP1, and CDK18-deficiency results in a decrease in both RAD17 and RAD9 chromatin retention in response to replication stress. Importantly, we demonstrate that these phenotypes are rescued by exogenous CDK18 in a kinase-dependent manner. Collectively, these data reveal a rate-limiting role for CDK18 in replication stress signalling and establish it as a novel regulator of genome integrity.


Assuntos
Quinases Ciclina-Dependentes/metabolismo , Replicação do DNA , Instabilidade Genômica , Transdução de Sinais , Estresse Fisiológico , Pontos de Checagem do Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Cromatina/genética , Cromatina/metabolismo , Aberrações Cromossômicas , Quinases Ciclina-Dependentes/química , Quinases Ciclina-Dependentes/genética , Dano ao DNA , Humanos , Fosforilação , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Interferência de RNA , RNA Interferente Pequeno/genética
3.
J Cell Sci ; 127(Pt 13): 2910-9, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24816561

RESUMO

Here, we identify coiled-coil domain-containing protein 13 (Ccdc13) in a genome-wide RNA interference screen for regulators of genome stability. We establish that Ccdc13 is a newly identified centriolar satellite protein that interacts with PCM1, Cep290 and pericentrin and prevents the accumulation of DNA damage during mitotic transit. Depletion of Ccdc13 results in the loss of microtubule organisation in a manner similar to PCM1 and Cep290 depletion, although Ccdc13 is not required for satellite integrity. We show that microtubule regrowth is enhanced in Ccdc13-depleted cells, but slowed in cells that overexpress Ccdc13. Furthermore, in serum-starved cells, Ccdc13 localises to the basal body, is required for primary cilia formation and promotes the localisation of the ciliopathy protein BBS4 to both centriolar satellites and cilia. These data highlight the emerging link between DNA damage response factors, centriolar and peri-centriolar satellites and cilia-associated proteins and implicate Ccdc13 as a centriolar satellite protein that functions to promote both genome stability and cilia formation.


Assuntos
Proteínas de Ciclo Celular/fisiologia , Centríolos/metabolismo , Cílios/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Instabilidade Genômica , Células HCT116 , Células HEK293 , Células HeLa , Humanos , Transfecção
4.
J Cell Sci ; 125(Pt 20): 4770-9, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22797915

RESUMO

The centrosome acts as a centre for microtubule organisation and plays crucial roles in cell polarity, migration, growth and division. Cep131 has recently been described as a basal body component essential for cilium formation, but its function in non-ciliogenic cells is unknown. We identified human Cep131 (also known as AZI1) in a screen for regulators of genome stability. We show that centrosomal localisation of Cep131 is cell-cycle-regulated and requires both an intact microtubule network and a functional dynein-dynactin transport system. Cep131 is recruited to centriolar satellites by PCM1, and localised to the centriolar core region by both pericentrin and Cep290. Depletion of Cep131 results in a reduction in proliferation rate, centriole amplification, an increased frequency of multipolar mitosis, chromosomal instability and an increase in post-mitotic DNA damage. These data therefore highlight the importance of human Cep131 for maintaining genomic integrity.


Assuntos
Proteínas de Ciclo Celular , Centríolos , Centrossomo , Instabilidade Genômica , Proteínas dos Microtúbulos , Antígenos de Neoplasias/metabolismo , Autoantígenos/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Centríolos/genética , Centríolos/ultraestrutura , Centrossomo/metabolismo , Centrossomo/ultraestrutura , Instabilidade Cromossômica , Proteínas do Citoesqueleto , Complexo Dinactina , Dineínas/metabolismo , Humanos , Proteínas dos Microtúbulos/genética , Proteínas dos Microtúbulos/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Mitose/genética , Proteínas de Neoplasias/metabolismo
5.
Thorax ; 68(11): 1037-42, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23404838

RESUMO

BACKGROUND: A recent rigorous study has shown that cytisine, a low-cost drug, is effective for smoking cessation. A number of earlier studies exist, mostly from former communist countries where cytisine has been used since the 1960s. The key question now is whether there is sufficient evidence to warrant licensing cytisine or whether more work is needed. A systematic review was undertaken to assess the efficacy of cytisine in smoking cessation. METHODS: The Cochrane Library, CINAHL, Embase, Medline and PsycINFO databases were searched for relevant data. Data from controlled trials were entered into two separate meta-analyses. The first considered the strictest definition of outcome and longest follow-up from all available studies and the second pooled outcomes from studies with biochemically validated abstinence and follow-up of 6 months or longer. RESULTS: Eight controlled trials were identified. Seven trials provided extractable data and, when pooled (first meta-analysis), produced a risk ratio (RR) of 1.57 (95% CI 1.42 to 1.74). Data from two high-quality studies (second meta-analysis) produced a pooled RR of 3.29 (95% CI 1.84 to 5.90). Patients on cytisine reported more gastrointestinal symptoms than patients on placebo (RR=1.76, 95% CI 1.28 to 2.42). There was no difference in overall reports of adverse events and no specific safety concerns emerged. CONCLUSIONS: Cytisine is an effective treatment for smoking cessation with efficacy comparable to that of other currently licensed treatments. Given its low cost and potential for public health benefit, expedited licensing of cytisine for smoking cessation is warranted.


Assuntos
Alcaloides/farmacologia , Saúde Pública , Abandono do Hábito de Fumar/métodos , Prevenção do Hábito de Fumar , Azocinas/farmacologia , Humanos , Nicotina/antagonistas & inibidores , Quinolizinas/farmacologia , Fumar/efeitos adversos , Resultado do Tratamento
6.
Front Public Health ; 11: 1111779, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37457247

RESUMO

Community-based participatory research (CBPR) and community engaged research (CEnR) are key to promoting community and patient engagement in actionable evidence-based strategies to improve research for health equity. Rapid growth of CBPR/CEnR research projects have led to the broad adoption of partnering principles in community-academic partnerships and among some health and academic organizations. Yet, transformation of principles into best practices that foster trust, shared power, and equity outcomes still remain fragmented, are dependent on individuals with long term projects, or are non-existent. This paper describes how we designed our Engage for Equity PLUS intervention that leverages the leadership and membership of champion teams (including community-engaged faculty, community partners and patient advocates) to improve organizational policies and practices to support equity based CBPR/CEnR. This article describes the feasibility and preliminary findings from engaging champion teams from three very different academic health centers. We reflect on the learnings from Engage for Equity PLUS; the adaptation of the intervention design and implementation, including the development of a new institutional assessment using mixed research methods; and our organizational theory of change. In summary, our design and preliminary data from the three academic health centers provide support for new attention to the role of institutional practices and processes needed to sustain equity-based patient and community-engaged research and CBPR and transform the field.


Assuntos
Pesquisa Participativa Baseada na Comunidade , Equidade em Saúde , Humanos , Pesquisa Participativa Baseada na Comunidade/métodos , Liderança , Participação do Paciente , Projetos de Pesquisa
7.
F1000Res ; 12: 954, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37799492

RESUMO

With diminishing returns and high clinical failure rates from traditional preclinical and animal-based drug discovery strategies, more emphasis is being placed on alternative drug discovery platforms. Ex vivo approaches represent a departure from both more traditional preclinical animal-based models and clinical-based strategies and aim to address intra-tumoural and inter-patient variability at an earlier stage of drug discovery. Additionally, these approaches could also offer precise treatment stratification for patients within a week of tumour resection in order to direct tailored therapy. One tumour group that could significantly benefit from such ex vivo approaches are high-grade gliomas, which exhibit extensive heterogeneity, cellular plasticity and therapy-resistant glioma stem cell (GSC) niches. Historic use of murine-based preclinical models for these tumours has largely failed to generate new therapies, resulting in relatively stagnant and unacceptable survival rates of around 12-15 months post-diagnosis over the last 50 years. The near universal use of DNA damaging chemoradiotherapy after surgical resection within standard-of-care (SoC) therapy regimens provides an opportunity to improve current treatments if we can identify efficient drug combinations in preclinical models that better reflect the complex inter-/intra-tumour heterogeneity, GSC plasticity and inherent DNA damage resistance mechanisms. We have therefore developed and optimised a high-throughput ex vivo drug screening platform; GliExP, which maintains GSC populations using immediately dissociated fresh surgical tissue. As a proof-of-concept for GliExP, we have optimised SoC therapy responses and screened 30+ small molecule therapeutics and preclinical compounds against tumours from 18 different patients, including multi-region spatial heterogeneity sampling from several individual tumours. Our data therefore provides a strong basis to build upon GliExP to incorporate combination-based oncology therapeutics in tandem with SoC therapies as an important preclinical alternative to murine models (reduction and replacement) to triage experimental therapeutics for clinical translation and deliver rapid identification of effective treatment strategies for individual gliomas.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Humanos , Animais , Camundongos , Glioblastoma/tratamento farmacológico , Avaliação Pré-Clínica de Medicamentos , Avatar , Neoplasias Encefálicas/tratamento farmacológico , Detecção Precoce de Câncer , Células-Tronco Neoplásicas
8.
J Public Health (Oxf) ; 34(3): 377-81, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22083256

RESUMO

BACKGROUND: During Ramadan, observant Muslims fast from sunrise to sunset for a month. Knowing whether Ramadan fasting affects body weight has implications for health advice to the Muslim community, for understanding the effects of skipping meals on body weight, and for general weight management advice. METHODS: We compared body weight before and after the Ramadan fast and 1 month later in observant Muslims attending a Mosque in East London, UK. RESULTS: In 202 participants who provided weight at the beginning and the end of Ramadan, there was a small weight decrease (-0.84 kg, 95% CI = -0.6 to -1, P < 0.0001), with 46% of participants losing >1 kg. Participants who fasted throughout Ramadan lost significantly more weight (1 kg) than those who occasionally broke fast (0.3 kg, P = 0.013). In 87 participants who provided weight at the beginning and end of Ramadan and also 1 month later, all the lost weight was regained (+0.1 kg, 95% CI = 0.2-0.5, P = 0.504 compared with baseline). CONCLUSIONS: Observers of Ramadan lose on average about a kilogram of weight over 4 weeks, and the lost weight is quickly regained. Current weight management treatments generally assume that skipping meals leads to weight gain and advise against it. The finding suggests that further research is needed on the justification of the 'do not skip meals' advice.


Assuntos
Índice de Massa Corporal , Jejum/fisiologia , Comportamento Alimentar , Islamismo , Redução de Peso , Adulto , Análise de Variância , Intervalos de Confiança , Jejum/efeitos adversos , Feminino , Humanos , Masculino , Fatores de Tempo
9.
PLoS Genet ; 5(1): e1000324, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19119425

RESUMO

The related PIK-like kinases Ataxia-Telangiectasia Mutated (ATM) and ATM- and Rad3-related (ATR) play major roles in the regulation of cellular responses to DNA damage or replication stress. The pro-apoptotic role of ATM and p53 in response to ionizing radiation (IR) has been widely investigated. Much less is known about the control of apoptosis following DNA replication stress. Recent work indicates that Chk1, the downstream phosphorylation target of ATR, protects cells from apoptosis induced by DNA replication inhibitors as well as IR. The aim of the work reported here was to determine the roles of ATM- and ATR-protein kinase cascades in the control of apoptosis following replication stress and the relationship between Chk1-suppressed apoptotic pathways responding to replication stress or IR. ATM and ATR/Chk1 signalling pathways were manipulated using siRNA-mediated depletions or specific inhibitors in two tumour cell lines or fibroblasts derived from patients with inherited mutations. We show that depletion of ATM or its downstream phosphorylation targets, NBS1 and BID, has relatively little effect on apoptosis induced by DNA replication inhibitors, while ATR or Chk1 depletion strongly enhances cell death induced by such agents in all cells tested. Furthermore, early events occurring after the disruption of DNA replication (accumulation of RPA foci and RPA34 hyperphosphorylation) in ATR- or Chk1-depleted cells committed to apoptosis are not detected in ATM-depleted cells. Unlike the Chk1-suppressed pathway responding to IR, the replication stress-triggered apoptotic pathway did not require ATM and is characterized by activation of caspase 3 in both p53-proficient and -deficient cells. Taken together, our results show that the ATR-Chk1 signalling pathway plays a major role in the regulation of death in response to DNA replication stress and that the Chk1-suppressed pathway protecting cells from replication stress is clearly distinguishable from that protecting cells from IR.


Assuntos
Apoptose , Caspase 3/metabolismo , Inibidores de Caspase , Proteínas de Ciclo Celular/metabolismo , Replicação do DNA/fisiologia , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia , Caspase 3/genética , Linhagem Celular Tumoral , Quinase 1 do Ponto de Checagem , Dano ao DNA , Proteínas de Ligação a DNA/metabolismo , Humanos , Radiação Ionizante , Transdução de Sinais , Proteínas Supressoras de Tumor/metabolismo
10.
Front Oncol ; 12: 841951, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35756657

RESUMO

Purpose: Around 5% of United States (U.S.) population identifies as Sexual and Gender Diverse (SGD), yet there is limited research around cancer prevention among these populations. We present multi-pronged, low-cost, and systematic recruitment strategies used to reach SGD communities in New Mexico (NM), a state that is both largely rural and racially/ethnically classified as a "majority-minority" state. Methods: Our recruitment focused on using: (1) Every Door Direct Mail (EDDM) program, by the United States Postal Services (USPS); (2) Google and Facebook advertisements; (3) Organizational outreach via emails to publicly available SGD-friendly business contacts; (4) Personal outreach via flyers at clinical and community settings across NM. Guided by previous research, we provide detailed descriptions on using strategies to check for fraudulent and suspicious online responses, that ensure data integrity. Results: A total of 27,369 flyers were distributed through the EDDM program and 436,177 impressions were made through the Google and Facebook ads. We received a total of 6,920 responses on the eligibility survey. For the 5,037 eligible respondents, we received 3,120 (61.9%) complete responses. Of these, 13% (406/3120) were fraudulent/suspicious based on research-informed criteria and were removed. Final analysis included 2,534 respondents, of which the majority (59.9%) reported hearing about the study from social media. Of the respondents, 49.5% were between 31-40 years, 39.5% were Black, Hispanic, or American Indian/Alaskan Native, and 45.9% had an annual household income below $50,000. Over half (55.3%) were assigned male, 40.4% were assigned female, and 4.3% were assigned intersex at birth. Transgender respondents made up 10.6% (n=267) of the respondents. In terms of sexual orientation, 54.1% (n=1371) reported being gay or lesbian, 30% (n=749) bisexual, and 15.8% (n=401) queer. A total of 756 (29.8%) respondents reported receiving a cancer diagnosis and among screen-eligible respondents, 66.2% reported ever having a Pap, 78.6% reported ever having a mammogram, and 84.1% reported ever having a colonoscopy. Over half of eligible respondents (58.7%) reported receiving Human Papillomavirus vaccinations. Conclusion: Study findings showcase effective strategies to reach communities, maximize data quality, and prevent the misrepresentation of data critical to improve health in SGD communities.

11.
Surg Endosc ; 25(5): 1594-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21072668

RESUMO

BACKGROUND: Internal hernia (IH) is one of the more acute and potentially devastating complications after laparoscopic gastric bypass (LGB). Currently, there is no way to predict which patients will develop IH. We propose that patients who undergo periods of rapid excess weight loss (EWL) following LGB are more likely to develop IH. METHODS: A retrospective review of a prospectively collected laparoscopic gastric bypass database from our bariatric center was performed. Patient data between 2002 and 2009 was reviewed. Demographics, initial body mass index (BMI), detailed weight loss curves, and morbidity, specifically IH, were reviewed. Statistical analysis was performed. Logistic regression analysis was used to obtain an adjusted odds ratio for rapid weight loss and hernia development. RESULTS: We reviewed all 934 LGB procedures performed. The average initial BMI was 49.1 kg/m2 (range=34-91 kg/m2). EWL based on our current averages at 1, 3, 6, 9, and 12 months postoperatively were 20, 40, 60, 75, and 85%. We statistically defined rapid EWL as greater than the 90th percentile for weight loss. Rapid EWL was noted in 33.2% (310/934) of patients. Fifty-eight (6.2%) patients were identified with IH. Of these, 27(46.5%) had periods of rapid EWL (odds ratio [OR]=1.83; 95% CI=1.07, 3.02). Bivariate analysis of patient factors that led to rapid EWL identified initial BMI (49.3 vs. 46.6 kg/m2) and rapid EWL as increasing the likelihood of developing IH (p=0.026). A multivariate logistic model for IH identified only rapid EWL as a predictive factor. Locations of IH were the jejunojejunostomy (24), Pedersen's defect (23), adhesions (9), and colonic mesentery (1). There were five patients with combined JJ and Pederson's hernias. CONCLUSION: Outcomes from missed IH can be catastrophic. In our large, single-center series, we have found that patients who undergo periods of rapid EWL are at nearly twice the risk for development of IH as the rest of the gastric bypass population.


Assuntos
Derivação Gástrica , Hérnia Abdominal/etiologia , Laparoscopia , Obesidade Mórbida/cirurgia , Redução de Peso , Adulto , Feminino , Derivação Gástrica/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
12.
Nucleic Acids Res ; 37(15): 5105-13, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19553191

RESUMO

Arsenic exposure constitutes one of the most widespread environmental carcinogens, and is associated with increased risk of many different types of cancers. Here we report that arsenite (As[III]) can induce both replication-dependent DNA double-strand breaks (DSB) and homologous recombination (HR) at doses as low as 5 microM (0.65 mg/l), which are within the typical doses often found in drinking water in contaminated areas. We show that the production of DSBs is dependent on active replication and is likely to be the result of conversion of a DNA single-strand break (SSB) into a toxic DSB when encountered by a replication fork. We demonstrate that HR is required for the repair of these breaks and show that a functional HR pathway protects against As[III]-induced cytotoxicity. In addition, BRCA2-deficient cells are sensitive to As[III] and we suggest that As[III] could be exploited as a therapy for HR-deficient tumours such as BRCA1 and BRCA2 mutated breast and ovarian cancers.


Assuntos
Arsenitos/toxicidade , Proteína BRCA2/metabolismo , Carcinógenos/toxicidade , Quebras de DNA de Cadeia Dupla , Reparo do DNA , Recombinação Genética , Animais , Linhagem Celular , Cricetinae , Cricetulus , Replicação do DNA
13.
Cancers (Basel) ; 13(5)2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33668183

RESUMO

Brain tumours kill more children and adults under 40 than any other cancer, with approximately half of primary brain tumours being diagnosed as high-grade malignancies known as glioblastomas. Despite de-bulking surgery combined with chemo-/radiotherapy regimens, the mean survival for these patients is only around 15 months, with less than 10% surviving over 5 years. This dismal prognosis highlights the urgent need to develop novel agents to improve the treatment of these tumours. To address this need, we carried out a human kinome siRNA screen to identify potential drug targets that augment the effectiveness of temozolomide (TMZ)-the standard-of-care chemotherapeutic agent used to treat glioblastoma. From this we identified ERK5/MAPK7, which we subsequently validated using a range of siRNA and small molecule inhibitors within a panel of glioma cells. Mechanistically, we find that ERK5 promotes efficient repair of TMZ-induced DNA lesions to confer cell survival and clonogenic capacity. Finally, using several glioblastoma patient cohorts we provide target validation data for ERK5 as a novel drug target, revealing that heightened ERK5 expression at both the mRNA and protein level is associated with increased tumour grade and poorer patient survival. Collectively, these findings provide a foundation to develop clinically effective ERK5 targeting strategies in glioblastomas and establish much-needed enhancement of the therapeutic repertoire used to treat this currently incurable disease.

14.
Lang Speech Hear Serv Sch ; 50(4): 477-492, 2019 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-31600468

RESUMO

Purpose The purpose of this tutorial is to explain key concepts about vocabulary acquisition and instruction and to translate research from middle school vocabulary interventions into practice recommendations for practitioners. In this tutorial, we consider the relationship between vocabulary and reading comprehension, describe vocabulary acquisition including the development of semantic networks, provide a review of high-quality middle school vocabulary studies, and make recommendations for practice. Method We reviewed the experimental and quasi-experimental literature examining the impact of vocabulary instruction on the vocabulary and reading comprehension development of middle school students. We searched multiple electronic databases (e.g., PsycInfo, ERIC, Scopus, Google Scholar) using combinations of specific search terms (i.e., vocabulary, intervention, instruction, middle school, adolescent), searched reviews of vocabulary research, and conducted bibliographic searches of included studies. We then extracted information from each included study about the intervention, participants, and outcomes. Results We identified 17 studies meeting our inclusion criteria. The majority of studies were conducted with students from low socioeconomic status backgrounds. Only 1 study focused exclusively on students with learning disabilities, language impairments, or reading disabilities, highlighting the need for more vocabulary experimental research studies with special populations of students in middle school. Conclusion After reviewing the middle school studies, we make 5 recommendations based on the literature: (a) teach vocabulary intentionally, (b) teach independent word-learning strategies (morphological analysis), (c) focus on developing semantic networks, (d) increase opportunities to use new words in discussion and writing, and (e) provide a motivating and language-rich learning environment.


Assuntos
Compreensão , Aprendizagem , Leitura , Vocabulário , Adolescente , Criança , Humanos , Desenvolvimento da Linguagem , Transtornos da Linguagem , Deficiências da Aprendizagem , Instituições Acadêmicas , Estudantes , Redação
15.
Oncotarget ; 9(50): 29508-29524, 2018 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-30034634

RESUMO

BACKGROUND: Cyclin-Dependent Kinases (CDKs) are established anti-cancer drug targets and a new generation of CDK inhibitors are providing clinical benefits to a sub-set of breast cancer patients. We have recently shown that human CDK18 promotes efficient cellular responses to replication stress. In the current study, we have investigated the clinicopathological and functional significance of CDK18 expression levels in breast cancers. RESULTS: High CDK18 protein expression was associated with a triple negative and basal-like phenotype (p = 0.021 and 0.027 respectively) as well as improved patient survival, which was particularly significant in ER negative breast cancers (n = 594, Log Rank 6.724, p = 0.01) and those treated with chemotherapy (n = 270, Log Rank 4.575, p = 0.03). In agreement with these clinical findings, breast cancer cells genetically manipulated using a dCRISPR approach to express high levels of endogenous CDK18 exhibited an increased sensitivity to replication stress-inducing chemotherapeutic agents, as a consequence to defective replication stress signalling at the molecular level. CONCLUSIONS: These data reveal that CDK18 protein levels may predict breast cancer disease progression and response to chemotherapy, and provide further rationale for potential targeting of CDK18 as part of novel anti-cancer strategies for human cancers. MATERIALS AND METHODS: CDK18 protein expression was evaluated in 1650 breast cancers and correlated to clinicopathological parameters and survival outcomes. Similar analyses were carried out for genetic and transcriptomic changes in CDK18 within several publically available breast cancer cohorts. Additionally, we used a deactivated CRISPR/Cas9 approach (dCRISPR) to elucidate the molecular consequences of heightened endogenous CDK18 expression within breast cancer cells.

16.
Sci Rep ; 6: 35548, 2016 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-27739501

RESUMO

It was recently discovered that vertebrate genomes contain multiple endogenised nucleotide sequences derived from the non-retroviral RNA bornavirus. Strikingly, some of these elements have been evolutionary maintained as open reading frames in host genomes for over 40 million years, suggesting that some endogenised bornavirus-derived elements (EBL) might encode functional proteins. EBLN1 is one such element established through endogenisation of the bornavirus N gene (BDV N). Here, we functionally characterise human EBLN1 as a novel regulator of genome stability. Cells depleted of human EBLN1 accumulate DNA damage both under non-stressed conditions and following exogenously induced DNA damage. EBLN1-depleted cells also exhibit cell cycle abnormalities and defects in microtubule organisation as well as premature centrosome splitting, which we attribute in part, to improper localisation of the nuclear envelope protein TPR. Our data therefore reveal that human EBLN1 possesses important cellular functions within human cells, and suggest that other EBLs present within vertebrate genomes may also possess important cellular functions.


Assuntos
Bornaviridae/metabolismo , Ciclo Celular/genética , Instabilidade Genômica , Microtúbulos/metabolismo , Nucleoproteínas/metabolismo , Proteína Quinase CDC2 , Linhagem Celular , Centrossomo/metabolismo , Ciclina B1/metabolismo , Dano ao DNA , Humanos , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Nucleoproteínas/deficiência , Ligação Proteica , Proteínas/metabolismo , Proteínas Proto-Oncogênicas/metabolismo
17.
Cell Rep ; 16(10): 2565-2575, 2016 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-27568553

RESUMO

Through an RNAi-based screen for previously uncharacterized regulators of genome stability, we have identified the human protein C5orf45 as an important factor in preventing the accumulation of DNA damage in human cells. Here, we functionally characterize C5orf45 as a binding partner of the MRE11-RAD50-NBS1 (MRN) damage-sensing complex. Hence, we rename C5orf45 as MRNIP for MRN-interacting protein (MRNIP). We find that MRNIP is rapidly recruited to sites of DNA damage. Cells depleted of MRNIP display impaired chromatin loading of the MRN complex, resulting in reduced DNA end resection and defective ATM-mediated DNA damage signaling, a reduced ability to repair DNA breaks, and radiation sensitivity. Finally, we show that MRNIP phosphorylation on serine 115 leads to its nuclear localization, and this modification is required for MRNIP's role in promoting genome stability. Collectively, these data reveal that MRNIP is an important component of the human DNA damage response.


Assuntos
Proteínas de Transporte/metabolismo , Dano ao DNA , Complexos Multiproteicos/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Quinase do Ponto de Checagem 2/metabolismo , Cromatina/metabolismo , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Reparo do DNA/efeitos da radiação , Endodesoxirribonucleases , Células HCT116 , Células HEK293 , Células HeLa , Humanos , Ligação Proteica/efeitos da radiação , Tolerância a Radiação/efeitos da radiação , Radiação Ionizante , Homologia de Sequência de Aminoácidos , Transdução de Sinais/efeitos da radiação
18.
BMC Obes ; 1: 10, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26217502

RESUMO

BACKGROUND: Mobile health (mHealth) behaviour change programmes use mobile phones and the internet to deliver health information and behaviour change support to participants. Such programmes offer a potentially cost-effective way to reach many individuals who do not currently access weight loss services. We developed a mHealth weight management programme using proven face-to-face behaviour change techniques and incorporating target population input. Our aim was to evaluate the feasibility, acceptability and potential effectiveness of this programme for ethnically diverse adults with a view to informing a larger trial. RESULTS: Fifty three adults who had a BMI of ≥25 kg/m(2) and wanted to lose weight (81% female, mean age 42 years, mean BMI 35.7 kg/m(2), 26% Maori, 34% Pacific) received the eight-week mHealth weight loss programme. Anthropometric measures were taken at two face-to-face assessments at baseline and 12-weeks (i.e. four weeks after cessation of intervention). Twelve-week follow-up measurements were available for 36/53 participants (68%). Non-completers were younger and more likely to be male and of Pacific ethnicity. Thirty five participants (66%) reported reading 'all or most' text messages sent and 96% responded to at least one text data collection question over the eight-week active intervention period. Eighty one per cent of participants logged in to the study website at least once during the eight-week study period. In the intention-to-treat analysis, mean weight change was -1.0 kg (SD 3.1) at 12 weeks (p = 0.024) and change in BMI was -0.34 kg/m(2) (SD 1.1) (p = 0.026). In the completers only analysis (n = 36), mean weight change was -1.4 kg (SD 3.6) (p = 0.023) and change in BMI was -0.50 kg/m(2) (SD 1.3) (p = 0.025). CONCLUSIONS: A mHealth weight management programme is feasible to deliver to an ethnically diverse population. Changes in body weight and BMI at 12 weeks indicate that the programme could be effective in supporting people with weight loss. However, the high dropout rate indicates a need for further improvements to the programme. TRIAL REGISTRATION: ACTRN12612000850875.

19.
Oncotarget ; 5(15): 6375-86, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25071007

RESUMO

Urothelial cell carcinoma of the bladder (UCC) is a common disease often characterized by FGFR3 dysregulation. Whilst upregulation of this oncogene occurs most frequently in low-grade non-invasive tumors, recent data reveal increased FGFR3 expression characterizes a common sub-type of invasive UCC sharing molecular similarities with breast cancer. These similarities include upregulation of the FOXA1 transcription factor and reduced expression of microRNAs-99a/100. We have previously identified direct regulation of FGFR3 by these two microRNAs and now search for further targets. Using a microarray meta-database we find potential FOXA1 regulation by microRNAs-99a/100. We confirm direct targeting of the FOXA1 3'UTR by microRNAs-99a/100 and also potential indirect regulation through microRNA-485-5p/SOX5/JUN-D/FOXL1 and microRNA-486/FOXO1a. In 292 benign and malignant urothelial samples, we find an inverse correlation between the expression of FOXA1 and microRNAs-99a/100 (r=-0.33 to -0.43, p<0.05). As for FGFR3 in UCC, tumors with high FOXA1 expression have lower rates of progression than those with low expression (Log rank p=0.009). Using global gene expression and CpG methylation profiling we find genotypic consequences of FOXA1 upregulation in UCC. Genetic changes are associated with regional hypomethylation, occur near FOXA1 binding sites, and mirror gene expression changes previously reported in FGFR3 mutant-UCC. These include gene silencing through aberrant hypermethylation (e.g. IGFBP3) and affect genes characterizing breast cancer sub-types (e.g. ERBB2). In conclusion, we have identified microRNAs-99a/100 mediate a direct relationship between FGFR3 and FOXA1 and potentially facilitate cross talk between these pathways in UCC.


Assuntos
Fator 3-alfa Nuclear de Hepatócito/genética , MicroRNAs/genética , Neoplasias da Bexiga Urinária/genética , Idoso , Idoso de 80 Anos ou mais , Feminino , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Humanos , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Prognóstico , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/metabolismo , Regulação para Cima , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia
20.
Cell Cycle ; 13(21): 3450-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25485589

RESUMO

We previously identified and characterized TELO2 as a human protein that facilitates efficient DNA damage response (DDR) signaling. A subsequent yeast 2-hybrid screen identified LARG; Leukemia-Associated Rho Guanine Nucleotide Exchange Factor (also known as Arhgef12), as a potential novel TELO2 interactor. LARG was previously shown to interact with Pericentrin (PCNT), which, like TELO2, is required for efficient replication stress signaling. Here we confirm interactions between LARG, TELO2 and PCNT and show that a sub-set of LARG co-localizes with PCNT at the centrosome. LARG-deficient cells exhibit replication stress signaling defects as evidenced by; supernumerary centrosomes, reduced replication stress-induced γH2AX and RPA nuclear foci formation, and reduced activation of the replication stress signaling effector kinase Chk1 in response to hydroxyurea. As such, LARG-deficient cells are sensitive to replication stress-inducing agents such as hydroxyurea and mitomycin C. Conversely we also show that depletion of TELO2 and the replication stress signaling kinase ATR leads to RhoA signaling defects. These data therefore reveal a level of crosstalk between the RhoA and DDR signaling pathways. Given that mutations in both ATR and PCNT can give rise to the related primordial dwarfism disorders of Seckel Syndrome and Microcephalic osteodysplastic primordial dwarfism type II (MOPDII) respectively, which both exhibit defects in ATR-dependent checkpoint signaling, these data also raise the possibility that mutations in LARG or disruption to RhoA signaling may be contributory factors to the etiology of a sub-set of primordial dwarfism disorders.


Assuntos
Fatores de Troca de Nucleotídeo Guanina Rho/metabolismo , Transdução de Sinais , Antígenos/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Centrossomo/metabolismo , Quinase 1 do Ponto de Checagem , Reparo do DNA , Replicação do DNA/efeitos dos fármacos , Células HCT116 , Células HEK293 , Células HeLa , Humanos , Hidroxiureia/farmacologia , Mitomicina/farmacologia , Fosforilação/efeitos dos fármacos , Proteínas Quinases/metabolismo , RNA Interferente Pequeno/metabolismo , Fatores de Troca de Nucleotídeo Guanina Rho/antagonistas & inibidores , Fatores de Troca de Nucleotídeo Guanina Rho/genética , Proteínas de Ligação a Telômeros/antagonistas & inibidores , Proteínas de Ligação a Telômeros/genética , Proteínas de Ligação a Telômeros/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo
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