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1.
Adv Exp Med Biol ; 1395: 9-15, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36527606

RESUMO

Broadband near-infrared spectroscopy (bNIRS) has the potential to provide non-invasive measures of cerebral haemodynamic changes alongside changes in cellular oxygen utilisation through the measurement of mitochondrial enzyme cytochrome-c-oxidase (oxCCO). It therefore provides the opportunity to explore brain function and specialisation, which remains largely unexplored in infancy. We used bNIRS to measure changes in haemodynamics and changes in oxCCO in 4-to-7-month-old infants over the occipital and right temporal and parietal cortices in response to social and non-social visual and auditory stimuli. Changes in concentration of oxygenated-haemoglobin (Δ[HbO2]), deoxygenated haemoglobin (Δ[HHb]) and change in the oxidation state of oxCCO (Δ[oxCCO]) were calculated using changes in attenuation of light at 120 wavelengths between 780 and900 nm, using the UCLn algorithm. For 4 infants, the attenuation changes in a subset of wavelengths were used to perform image reconstruction, in an age-matched infant model, for channels over the right parietal and temporal cortices, using a multispectral approach which allows direct reconstruction of concentration change data. The volumetric reconstructed images were mapped onto the cortical surface to visualise the reconstructed changes in concentration of HbO2 and HHb and changes in metabolism for both social and non-social stimuli. Spatially localised activation was observed for Δ[oxCCO] and Δ[HbO2] over the temporo-parietal region, in response to the social stimulus. This study provides the first reconstructed images of changes in metabolism in healthy, awake infants.


Assuntos
Encéfalo , Espectroscopia de Luz Próxima ao Infravermelho , Lactente , Humanos , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Oxiemoglobinas/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Metabolismo Energético , Hemoglobinas/metabolismo
2.
Comput Sci Eng ; 23(1): 25-34, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35414796

RESUMO

The novel coronavirus (SARS-CoV-2) emerged in late 2019 and spread globally in early 2020. Initial reports suggested the associated disease, COVID-19, produced rapid epidemic growth and caused high mortality. As the virus sparked local epidemics in new communities, health systems and policy makers were forced to make decisions with limited information about the spread of the disease. We developed a compartmental model to project COVID-19 healthcare demands that combined information regarding SARS-CoV-2 transmission dynamics from international reports with local COVID-19 hospital census data to support response efforts in three Metropolitan Statistical Areas (MSAs) in Texas, USA: Austin-Round Rock, Houston-The Woodlands-Sugar Land, and Beaumont-Port Arthur. Our model projects that strict stay-home orders and other social distancing measures could suppress the spread of the pandemic. Our capacity to provide rapid decision-support in response to emerging threats depends on access to data, validated modeling approaches, careful uncertainty quantification, and adequate computational resources.

3.
Breast Cancer Res Treat ; 180(3): 735-745, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32060782

RESUMO

INTRODUCTION: Axillary lymph node dissection (ALND) has been considered essential for the staging of breast cancer (BC). As the impact of tumor biology on clinical outcomes is recognized, a surgical de-escalation approach is being implemented. We performed a retrospective study focused on surgical management of the axilla in invasive lobular carcinoma (ILC) versus invasive ductal carcinoma (IDC). MATERIALS AND METHODS: 1151 newly diagnosed BCs, IDCs (79.6%) or ILCs (20.4%), were selected among patients treated at our Breast Cancer Unit from 2012 to 2018. Tumor characteristics and clinical information were collected and predictors of further metastasis after positive sentinel lymph node biopsy (SLNB) analyzed in relation to disease-free survival (DFS) and overall survival (OS). RESULTS: 27.5% of patients with ILC had ≥ 3 metastatic lymph nodes at ALND after positive SLNB versus 11.48% of IDCs (p = 0.04). Risk predictors of further metastasis at ALND were the presence of > 2 positive lymph nodes at SLNB (OR = 4.72, 95% CI 1.15-19.5 p = 0.03), T3-T4 tumors (OR = 4.93, 95% CI 1.10-22.2, p = 0.03) and Non-Luminal BC (OR = 2.74, 95% CI 1.16-6.50, p = 0.02). The lobular histotype was not associated with the risk of further metastasis at ALND (OR = 1.62, 95% CI 0.77-3.41, p = 0.20). CONCLUSIONS: ILC histology is not associated with higher risk of further metastasis at ALND in our analysis. However, surgical management decisions should be taken considering tumor histotype, biology and expected sensitivity to adjuvant therapies.


Assuntos
Neoplasias da Mama/mortalidade , Carcinoma Ductal de Mama/mortalidade , Carcinoma Lobular/mortalidade , Excisão de Linfonodo/mortalidade , Mastectomia/mortalidade , Biópsia de Linfonodo Sentinela/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Axila , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Carcinoma Lobular/patologia , Carcinoma Lobular/cirurgia , Gerenciamento Clínico , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
4.
BJOG ; 126(2): 280-286, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29443441

RESUMO

OBJECTIVE: Comparison of live birth rates and the perinatal outcomes after fresh and frozen embryo transfer between time-lapse imaging (TLI) and standard culture (SC) incubators. DESIGN: Retrospective cohort study. SETTING: A single tertiary level IVF unit. POPULATION: Women undergoing IVF between January 2014 and October 2015. METHODS: Comparison was done between 1064 IVF cycles using TLI (TLI cycles) and 818 IVF cycles using SC (SC cycles). MAIN OUTCOME MEASURES: Cumulative live birth rate per oocyte retrieval and perinatal outcomes including birthweight, gestational age, preterm birth (PTB) (<37 weeks), early preterm birth (PTB; <32 weeks), low birthweight (LBW; <2500 g), very LBW (<1500 g) and macrosomia (>4500 g). RESULTS: The fresh embryo transfer live birth rate was noted to be higher for TLI cycles [TLI 36.8 versus SC 33.9%, adjusted odds ratio (aOR) 1.28, 95% CI 1.05-1.57], but the frozen embryo transfer live birth rates were not significantly different. The mean birthweight was higher in the TLI group after both fresh [adjusted mean difference (aMD) 174.78 g, 95% CI 64.80-284.77] and frozen embryo transfers (aMD 175.91 g, 95% CI 16.98-334.84). After a fresh embryo transfer, there was a lower risk of early PTB and very LBW in the TLI group. Among frozen embryo transfers, there was a lower risk of early PTB and LBW in the TLI group. CONCLUSIONS: TLI incubators are associated with improved perinatal outcomes and higher mean birthweight after fresh and frozen embryo transfer. TWEETABLE ABSTRACT: Time-lapse imaging incubators in IVF improve perinatal outcomes after both fresh and frozen embryo transfers.


Assuntos
Coeficiente de Natalidade , Técnicas de Cultura Embrionária/instrumentação , Transferência Embrionária/métodos , Incubadoras , Imagem com Lapso de Tempo , Adulto , Peso ao Nascer , Criopreservação/estatística & dados numéricos , Transferência Embrionária/estatística & dados numéricos , Feminino , Humanos , Gravidez , Resultado da Gravidez/epidemiologia , Estudos Retrospectivos
5.
Eur J Neurosci ; 47(6): 736-749, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29057543

RESUMO

Autism spectrum disorder (ASD) is a common, highly heritable, developmental disorder and later-born siblings of diagnosed children are at higher risk of developing ASD than the general population. Although the emergence of behavioural symptoms of ASD in toddlerhood is well characterized, far less is known about development during the first months of life of infants at familial risk. In a prospective longitudinal study of infants at familial risk followed to 36 months, we measured functional near-infrared spectroscopy (fNIRS) brain responses to social videos of people (i.e. peek-a-boo) compared to non-social images (vehicles) and human vocalizations compared to non-vocal sounds. At 4-6 months, infants who went on to develop ASD at 3 years (N = 5) evidenced-reduced activation to visual social stimuli relative to low-risk infants (N = 16) across inferior frontal (IFG) and posterior temporal (pSTS-TPJ) regions of the cortex. Furthermore, these infants also showed reduced activation to vocal sounds and enhanced activation to non-vocal sounds within left lateralized temporal (aMTG-STG/pSTS-TPJ) regions compared with low-risk infants and high-risk infants who did not develop ASD (N = 15). The degree of activation to both the visual and auditory stimuli correlated with parent-reported ASD symptomology in toddlerhood. These preliminary findings are consistent with later atypical social brain responses seen in children and adults with ASD, and highlight the need for further work interrogating atypical processing in early infancy and how it may relate to later social interaction and communication difficulties characteristic of ASD.


Assuntos
Percepção Auditiva/fisiologia , Transtorno do Espectro Autista/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Percepção Social , Lobo Temporal/fisiopatologia , Percepção Visual/fisiologia , Transtorno do Espectro Autista/diagnóstico por imagem , Feminino , Neuroimagem Funcional , Predisposição Genética para Doença , Humanos , Lactente , Estudos Longitudinais , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Irmãos , Espectroscopia de Luz Próxima ao Infravermelho , Percepção da Fala/fisiologia , Lobo Temporal/diagnóstico por imagem
6.
Oral Dis ; 24(5): 732-740, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29243374

RESUMO

OBJECTIVE: To define molecular differences between autofluorescence and white light defined excision margins in oral potentially malignant disorders (OPMD) using transcriptome expression profiles. MATERIALS AND METHODS: Excisional biopsy specimens were taken from 11 patients at three different sites for each lesion: centre, white light margin and autofluorescence margin. The lesions were diagnosed histopathologically as oral epithelial dysplasia, oral lichenoid dysplasia, oral lichen planus or other. Transcriptome analysis was performed by RNA sequencing, hierarchical clustering, differential expression and biological pathway analysis. RESULTS: For hierarchical clustering, the samples broadly clustered according to histology rather than the margins with lichenoid samples clustering together. Differential expression analysis showed that independent of histology, there was greater molecular dysregulation between the lesion centre and autofluorescence margin compared to the lesion centre and white light margin. Furthermore, the autofluorescence and white light margins were molecularly distinct, indicating the white light margins harboured abnormality. CONCLUSION: Our results indicate that the molecular profile of OPMD changes with divergence away from the centre of the lesion, and that autofluorescence determined margins are superior to the white light margin in achieving a clear molecular margin when excising an OPMD.


Assuntos
Líquen Plano Bucal/genética , Margens de Excisão , Imagem Óptica , Lesões Pré-Cancerosas/genética , RNA/análise , Idoso , Feminino , Fluorescência , Humanos , Líquen Plano Bucal/cirurgia , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/cirurgia , Análise de Sequência de RNA , Transcriptoma
7.
Adv Exp Med Biol ; 1072: 7-12, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30178316

RESUMO

A novel multi-wavelength broadband near infrared spectroscopy (NIRS) system has been employed to simultaneously measure haemodynamic changes alongside changes in cellular oxygen utilization by measurement of oxidation state of mitochondrial enzyme cytochrome-c-oxidase (oxCCO). The aim of this study was to investigate the role of oxCCO in neural responses to functional activation in infants. Studies were performed using a NIRS broadband system in 33 typically developing infants aged between 4 and 6 months. Responses were recorded over the right temporal lobe while infants were presented with engaging videos containing social and non-social content. Changes in the concentration of oxyhaemoglobin (Δ[HbO2]), deoxyhaemoglobin (Δ[HHb]) and Δ[oxCCO] were calculated using changes in attenuation of light at 120 wavelengths between 780 and 900 nm using the UCLn algorithm. The algorithm was also used to fit (a) HbO2 and HHb spectra (2 component fit) and (b) HbO2, HHb and oxCCO (3 component fit) to the change in attenuation occurring within an experimental block in different participants. Residuals resulting from these two fits were compared with oxidized-minus reduced CCO spectrum, calculated using the CCO specific extinction coefficient. A significant increase in oxCCO was found in response to the social stimuli (maximum increase 0.238 ± 0.13 µM). Residuals analysis showed that the best fits were achieved when oxCCO was included as a tissue chromophore. These results are the first reported significant change in oxCCO to stimulus-evoked activation in infants and may reveal vital information about oxygen metabolism during functional activation in the developing human brain.


Assuntos
Encéfalo/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Consumo de Oxigênio/fisiologia , Oxigênio/metabolismo , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Humanos , Lactente
8.
Cereb Cortex ; 25(10): 3779-87, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25404469

RESUMO

The ability to differentiate one's body from others is a fundamental aspect of social perception and has been shown to involve the integration of sense modalities attributable to the self. Though behavioral studies in infancy have investigated infants' discrimination of body-related multisensory stimuli, whether they attribute this information as belonging to the self is still unknown. In human adults, neuroimaging studies have demonstrated the recruitment of a specific set of brain regions in response to body-related multisensory integration. To test whether the infant brain integrates this information similarly to adults, in a first functional near-infrared spectroscopy study we investigated the role of visual-proprioceptive feedback when temporal cues are manipulated by showing 5-month-old infants an online video of their own face while the infant was performing movements. To explore the role of body-related contingency further, in a second study we investigated whether cortical activation in response to self-initiated movements and external tactile stimulation was similar to that found in the first study. Our results indicate that infants' specialized cortical activation in response to body-related contingencies is similar to brain activation seen in response to body awareness in adults.


Assuntos
Conscientização/fisiologia , Córtex Cerebral/fisiologia , Autoimagem , Retroalimentação Sensorial/fisiologia , Feminino , Humanos , Lactente , Masculino , Propriocepção/fisiologia , Desempenho Psicomotor/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho , Percepção do Tato/fisiologia , Percepção Visual/fisiologia
9.
Adv Exp Med Biol ; 876: 273-279, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26782222

RESUMO

A pilot study was conducted to assess the feasibility of using fNIRS as an alternative to behavioral assessments of cognitive development with infants in rural Africa. We report preliminary results of a study looking at working memory in 12-16-month-olds and discuss the benefits and shortcomings for the potential future use of fNIRS to investigate the effects of nutritional insults and interventions in global health studies.


Assuntos
Memória de Curto Prazo , Espectroscopia de Luz Próxima ao Infravermelho/métodos , África , Humanos , Lactente , Projetos Piloto , População Rural
10.
Br J Cancer ; 112(8): 1411-20, 2015 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-25742471

RESUMO

INTRODUCTION: Recent discoveries in cancer research have revealed a plethora of clinically actionable mutations that provide therapeutic, prognostic and predictive benefit to patients. The feasibility of screening mutations as part of the routine clinical care of patients remains relatively unexplored as the demonstration of massively parallel sequencing (MPS) of tumours in the general population is required to assess its value towards the health-care system. METHODS: Cancer 2015 study is a large-scale, prospective, multisite cohort of newly diagnosed cancer patients from Victoria, Australia with 1094 patients recruited. MPS was performed using the Illumina TruSeq Amplicon Cancer Panel. RESULTS: Overall, 854 patients were successfully sequenced for 48 common cancer genes. Accurate determination of clinically relevant mutations was possible including in less characterised cancer types; however, technical limitations including formalin-induced sequencing artefacts were uncovered. Applying strict filtering criteria, clinically relevant mutations were identified in 63% of patients, with 26% of patients displaying a mutation with therapeutic implications. A subset of patients was validated for canonical mutations using the Agena Bioscience MassARRAY system with 100% concordance. Whereas the prevalence of mutations was consistent with other institutionally based series for some tumour streams (breast carcinoma and colorectal adenocarcinoma), others were different (lung adenocarcinoma and head and neck squamous cell carcinoma), which has significant implications for health economic modelling of particular targeted agents. Actionable mutations in tumours not usually thought to harbour such genetic changes were also identified. CONCLUSIONS: Reliable delivery of a diagnostic assay able to screen for a range of actionable mutations in this cohort was achieved, opening unexpected avenues for investigation and treatment of cancer patients.


Assuntos
Análise Mutacional de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Proteínas de Neoplasias/genética , Neoplasias/genética , DNA de Neoplasias/análise , Feminino , Humanos , Estudos Longitudinais , Masculino , Mutação , Estudos Prospectivos
11.
Br J Cancer ; 112(1): 52-60, 2015 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-25461806

RESUMO

PURPOSE: To assess whether the combination of letrozole, metronomic cyclophosphamide and sorafenib (LCS) is well tolerated and shows activity in primary breast cancer (BC). METHODS: Thirteen oestrogen receptor-positive, postmenopausal, T2-4, N0-1 BC patients received the LCS combination for 6 months. In these patients we examined the pharmacokinetics of sorafenib and cyclophosphamide, toxicity of the regimen, the clinical response to therapy and changes in the levels of biologically relevant biomarkers. RESULTS: Adequate plasma concentrations of sorafenib were achieved in patients when it was dosed in combination with L+C. The mean plasma concentrations of C were consistently lower following administration of LCS, compared with administration of L+C only. The most common drug-related grade 3/4 adverse events were skin rash (69.3%), hand-foot skin reaction (69.3%) and diarrhoea (46.1%). According to RECIST Criteria, a clinical complete response was observed in 6 of 13 patients. A significant reduction in tumour size, evaluated with MRI, was also observed between baseline and 14 days of treatment in all 13 patients (P=0.005). A significant reduction in SUV uptake, measured by (18)FDG-PET/CT, was observed in all patients between baseline and 30 days of treatment (P=0.015) and between baseline and definitive surgery (P=0.0002). Using modified CT Criteria, a response was demonstrated in 8 out of 10 evaluable patients at 30 days and in 11 out of 13 evaluable patients at the definitive surgery. A significant reduction in Ki67 expression was observed in all patients at day 14 compared with baseline (P<0.00001) and in 9 out of 13 patients at the definitive surgery compared with baseline (P<0.03). There was also a significant suppression of CD31 and VEGF-A expression in response to treatment (P=0.01 and P=0.007, respectively). CONCLUSIONS: The LCS combination is feasible and tolerable. The tumour response and target biomarker modulation indicate that the combination is clinically and biologically active.


Assuntos
Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Administração Metronômica , Idoso , Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Ciclofosfamida/farmacocinética , Feminino , Humanos , Letrozol , Pessoa de Meia-Idade , Niacinamida/administração & dosagem , Niacinamida/efeitos adversos , Niacinamida/análogos & derivados , Niacinamida/farmacocinética , Nitrilas/administração & dosagem , Nitrilas/efeitos adversos , Nitrilas/farmacocinética , Compostos de Fenilureia/administração & dosagem , Compostos de Fenilureia/efeitos adversos , Compostos de Fenilureia/farmacocinética , Ensaios Clínicos Controlados Aleatórios como Assunto , Sorafenibe , Triazóis/administração & dosagem , Triazóis/efeitos adversos , Triazóis/farmacocinética
12.
Phys Rev Lett ; 115(5): 052702, 2015 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-26274415

RESUMO

26Al is an important radioisotope in astrophysics that provides evidence of ongoing nucleosynthesis in the Galaxy. The 23Na(α, p)26Mg reaction has been identified by a sensitivity study as being one of the most important reactions for the production of 26Al in the convective C/Ne burning shell of massive stars. Owing to large uncertainties in previous experimental data, model calculations are used for the reaction rate of 23Na(α, p)26Mg in this sensitivity study. Current experimental data suggest a reaction rate a factor of ∼40 higher than model calculations. However, a new measurement of this reaction cross section has been made in inverse kinematics in the energy range E(c.m.)=1.28-3.15 MeV at TRIUMF, and found to be in reasonable agreement with the model calculation. A new reaction rate is calculated and tight constraints on the uncertainty in the production of 26Al, due to this reaction, are determined.

13.
Br J Cancer ; 111(12): 2351-60, 2014 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-25490678

RESUMO

BACKGROUND: Male breast cancer (MBC) is still poorly understood with a large proportion arising in families with a history of breast cancer. Genomic studies have focused on germline determinants of MBC risk, with minimal knowledge of somatic changes in these cancers. METHODS: Using a TruSeq amplicon cancer panel, this study evaluated 48 familial MBCs (3 BRCA1 germline mutant, 17 BRCA2 germline mutant and 28 BRCAX) for hotspot somatic mutations and copy number changes in 48 common cancer genes. RESULTS: Twelve missense mutations included nine PIK3CA mutations (seven in BRCAX patients), two TP53 mutations (both in BRCA2 patients) and one PTEN mutation. Common gains were seen in GNAS (34.1%) and losses were seen in GNAQ (36.4%), ABL1 (47.7%) and ATM (34.1%). Gains of HRAS (37.5% vs 3%, P=0.006), STK11 (25.0% vs 0%, P=0.01) and SMARCB1 (18.8% vs 0%, P=0.04) and the loss of RB1 (43.8% vs 13%, P=0.03) were specific to BRCA2 tumours. CONCLUSIONS: This study is the first to perform high-throughput somatic sequencing on familial MBCs. Overall, PIK3CA mutations are most commonly seen, with fewer TP53 and PTEN mutations, similar to the profile seen in luminal A female breast cancers. Differences in mutation profiles and patterns of gene gains/losses are seen between BRCA2 (associated with TP53/PTEN mutations, loss of RB1 and gain of HRAS, STK11 and SMARCB1) and BRCAX (associated with PIK3CA mutations) tumours, suggesting that BRCA2 and BRCAX MBCs may be distinct and arise from different tumour pathways. This has implications on potential therapies, depending on the BRCA status of MBC patients.


Assuntos
Neoplasias da Mama Masculina/genética , Genes p53 , Mutação , PTEN Fosfo-Hidrolase/genética , Proteína Supressora de Tumor p53/genética , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama Masculina/enzimologia , Neoplasias da Mama Masculina/metabolismo , Análise Mutacional de DNA , Feminino , Predisposição Genética para Doença , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino
14.
Br J Cancer ; 110(6): 1606-13, 2014 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-24548858

RESUMO

BACKGROUND: RAD21 is a component of the cohesion complex and is integral to chromosome segregation and error-free DNA repair. RAD21 is functionally important in tumour progression but its role in colorectal carcinoma (CRC) is unclear. We therefore assessed its clinicopathological and prognostic significance in CRC, as well as its effect on chemosensitivity. METHODS: A retrospective observation study examined RAD21 expression in 652 CRCs using a tissue microarray approach. Correlation with clinicopathological factors including gender, tumour grade, mucinous subtype, TNM stage, disease-specific survival (DSS), BRAF and KRAS mutation status, tumour p53 immunostaining, tumour microsatellite instability and tumour CpG island methylator phenotype was performed. Colorectal cancer cell clones with stable RAD21 knockdown were generated and tested for cellular sensitivity to conventional chemotherapeutic drugs. RESULTS: RAD21 expression was significantly correlated with male gender (56.7% vs 43.3%, P=0.02), well-differentiated histology (14.4% vs 4.0%, P=0.0001), higher T-stage (36.1% vs 27.0%, P=0.01), presence of metastasis (18.8% vs 12.6%, P=0.03), and shorter DSS (hazard ratio (HR) 1.4, 95% CI 1.1 to 1.9, P=0.01) in both univariate and multivariate analysis. RAD21 expression was associated with shorter DSS in patients with KRAS mutant tumours (HR:2.6, 95% CI:1.4-4.3, P=0.001) and in patients receiving adjuvant chemoradiotherapy (HR:1.9, 95% CI:1.2-3.0, P=0.008). Colorectal cancer cells with RAD21 knockdown exhibited enhanced sensitivity to 5-fluorouracil, either alone or in combination with oxaliplatin. CONCLUSIONS: RAD21 expression in CRC is associated with aggressive disease especially in KRAS mutant tumours and resistance to chemoradiotherapy. RAD21 may be an important novel therapeutic target.


Assuntos
Biomarcadores Tumorais/biossíntese , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Mutação , Proteínas Nucleares/biossíntese , Fosfoproteínas/biossíntese , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Proteínas de Ciclo Celular , Neoplasias Colorretais/patologia , Proteínas de Ligação a DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Proteínas Nucleares/genética , Fosfoproteínas/genética , Prognóstico , Proteínas Proto-Oncogênicas p21(ras) , Estudos Retrospectivos , Fatores Sexuais , Análise Serial de Tecidos
15.
Br J Cancer ; 111(1): 46-54, 2014 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-24874483

RESUMO

BACKGROUND: Stratification of patients for treatment of ductal carcinoma in situ (DCIS) is suboptimal, with high systemic overtreatment rates. METHODS: A training set of 95 tumours from women with pure DCIS were immunostained for proteins involved in cell survival, hypoxia, growth factor and hormone signalling. A generalised linear regression with regularisation and variable selection was applied to a multiple covariate Cox survival analysis with recurrence-free survival 10-fold cross-validation and leave-one-out iterative approach were used to build and test the model that was validated using an independent cohort of 58 patients with pure DCIS. The clinical role of a COX-2-targeting agent was then tested in a proof-of-concept neoadjuvant randomised trial in ER-positive DCIS treated with exemestane 25 mg day(-1)± celecoxib 800 mg day(-1). RESULTS: The COX-2 expression was an independent prognostic factor for early relapse in the training (HR 37.47 (95% CI: 5.56-252.74) P=0.0001) and independent validation cohort (HR 3.9 (95% CI: 1.8-8.3) P=0.002). There was no significant interaction with other clinicopathological variables. A statistically significant reduction of Ki-67 expression after treatment with exemestane ± celecoxib was observed (P<0.02) with greater reduction in the combination arm (P<0.004). Concomitant reduction in COX-2 expression was statistically significant in the exemestane and celecoxib arm (P<0.03) only. CONCLUSIONS: In patients with DCIS, COX-2 may predict recurrence, aiding clinical decision making. A combination of an aromatase inhibitor and celecoxib has significant biological effect and may be integrated into treatment of COX2-positive DCIS at high risk of recurrence.


Assuntos
Androstadienos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/enzimologia , Carcinoma Intraductal não Infiltrante/tratamento farmacológico , Carcinoma Intraductal não Infiltrante/enzimologia , Ciclo-Oxigenase 2/biossíntese , Androstadienos/administração & dosagem , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Celecoxib , Estudos de Coortes , Ciclo-Oxigenase 2/genética , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Recidiva Local de Neoplasia/enzimologia , Recidiva Local de Neoplasia/patologia , Prognóstico , Pirazóis/administração & dosagem , Sulfonamidas/administração & dosagem , Análise de Sobrevida
16.
Br J Cancer ; 111(12): 2254-61, 2014 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-25321190

RESUMO

BACKGROUND: Preoperative radiotherapy (RT) is commonly used to treat localised soft-tissue sarcomas (STS). Hypoxia is an important determinant of radioresistance. Whether antiangiogenic therapy can 'normalise' tumour vasculature, thereby improving oxygenation, remains unknown. METHODS: Two cohorts were prospectively enrolled. Cohort A evaluated the implications of hypoxia in STS, using the hypoxic tracer (18)F-azomycin arabinoside (FAZA-PET). In cohort B, sunitinib was added to preoperative RT in a dose-finding phase 1b/2 design. RESULTS: In cohort A, 13 out of 23 tumours were hypoxic (FAZA-PET), correlating with metabolic activity (r(2)=0.85; P<0.001). Two-year progression-free (PFS) and overall (OS) survival were 61% (95% CI: 0.44-0.84) and 87% (95% CI: 0.74-1.00), respectively. Hypoxia was associated with radioresistance (P=0.012), higher local recurrence (Hazard ratio (HR): 10.2; P=0.02), PFS (HR: 8.4; P=0.02), and OS (HR: 41.4; P<0.04). In Cohort B, seven patients received sunitinib at dose level (DL): 0 (50 mg per day for 2 weeks before RT; 25 mg per day during RT) and two patients received DL: -1 (37.5 mg per day for entire period). Dose-limiting toxicities were observed in 4 out of 7 patients at DL 0 and 2 out of 2 patients at DL -1, resulting in premature study closure. Although there was no difference in PFS or OS, patients receiving sunitinib had higher local failure (HR: 8.1; P=0.004). CONCLUSION: In STS, hypoxia is associated with adverse outcomes. The combination of sunitinib with preoperative RT resulted in unacceptable toxicities, and higher local relapse rates.


Assuntos
Antineoplásicos/administração & dosagem , Indóis/administração & dosagem , Pirróis/administração & dosagem , Sarcoma/tratamento farmacológico , Sarcoma/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Recidiva Local de Neoplasia , Tomografia por Emissão de Pósitrons , Estudos Prospectivos , Radioterapia Adjuvante , Sunitinibe
17.
Ann Oncol ; 25(12): 2392-2397, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25231954

RESUMO

BACKGROUND: The promyelocytic leukemia (PML) tumor suppressor plays an important role in the response to a variety of cellular stressors and its expression is downregulated or lost in a range of human tumors. We have previously shown that the E3 ligase E6-associated protein (E6AP) is an important regulator of PML protein stability but the relationship and clinical impact of PML and E6AP expression in prostatic carcinoma is unknown. METHODS: E6AP and PML expression was assessed in tissue microarrays from a phase I discovery cohort of 170 patients treated by radical prostatectomy for localized prostate cancer (PC). Correlation analysis was carried out between PML and E6AP expression and clinicopathological variates including PSA as a surrogate of disease recurrence. The results were confirmed in a phase II validation cohort of 318 patients with associated clinical recurrence and survival data. RESULTS: Survival analysis of the phase I cohort revealed that patients whose tumors showed reduced PML and high E6AP expression had reduced time to PSA relapse (P = 0.012). This was confirmed in the phase II validation cohort where the expression profile of high E6AP/low PML was significantly associated with reduced time to PSA relapse (P < 0.001), clinical relapse (P = 0.016) and PC-specific death (P = 0.014). In multivariate analysis, this expression profile was an independent prognostic indicator of PSA relapse and clinical relapse independent of clinicopathologic factors predicting recurrence. CONCLUSION: This study identifies E6AP and PML as potential prognostic markers in localized prostate carcinoma and supports a role for E6AP in driving the downregulation or loss of PML expression in prostate carcinomas.


Assuntos
Proteínas Nucleares/metabolismo , Neoplasias da Próstata/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Estudos de Coortes , Progressão da Doença , Humanos , Masculino , Proteína da Leucemia Promielocítica , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia
18.
Breast Cancer Res Treat ; 143(2): 385-92, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24318467

RESUMO

Basal-like and triple-negative breast cancers usually display a high level of genomic instability and often carry TP53 mutations. Mutations in EGFR have been reported in about 10 % triple-negative tumours from Chinese women, and there is some evidence that triple-negative and basal-like tumours might carry additional mutations against which targeted therapies are available. We, therefore, sought to determine the frequency of 238 targetable mutations in 19 oncogenes (including EGFR) in a panel of basal-like and triple-negative breast cancers from Caucasian women. We used the OncoCarta panel to screen for 238 mutations across 19 common oncogenes in 107 basal-like and triple-negative breast cancers from Caucasian women. Mutations were then verified using Sanger sequencing or primer extension by iPLEX. We identified and validated 10 mutations across five genes. Most of the mutations were observed in the PIK3CA gene (18/107, 16.8 %), while mutations in KRAS, NRAS, MET and AKT1 were present in only one tumour each (1/107, 0.9 %). Among the missense substitutions in PIK3CA the point mutation resulting in the amino acid change H1047R was the most frequent (8/18, 44 %). All mutations were mutually exclusive, apart from one basal-like breast tumour which harboured mutations in both MET (p.T992I) and PIK3CA (p.H1047R). We did not identify any mutations in the EGFR gene. In conclusion, we found that with the exception of mutations in PIK3CA, these actionable oncogenic mutations on the Oncocarta panel are rare in basal-like and triple-negative breast cancers from Caucasian women. Custom panels, designed to detect mutations identified by exome sequencing of basal-like and triple-negative breast cancers, are, therefore, needed to identify women who might be eligible for targeted treatment.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias de Mama Triplo Negativas/genética , População Branca/genética , Sequência de Bases , Classe I de Fosfatidilinositol 3-Quinases , Receptores ErbB/genética , Feminino , GTP Fosfo-Hidrolases/genética , Frequência do Gene , Humanos , Proteínas de Membrana/genética , Mutação , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Análise de Sequência de DNA , Proteínas ras/genética
19.
Adv Exp Med Biol ; 812: 263-269, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24729242

RESUMO

We used optical topography (OT) to investigate cognitive function in infants in rural Gambia. Images of changes in oxyhaemoglobin and deoxyhaemoglobin concentrations were reconstructed using a multispectral algorithm which uses the finite element method (FEM) to model the propagation of light through scattering tissue using the diffusion equation. High quality OT data enabled us to reconstruct images with robust representation of haemodynamic changes. OT is a feasible neuroimage technology for this resource-poor setting.


Assuntos
Encéfalo/fisiologia , Algoritmos , Análise de Elementos Finitos , Gâmbia , Humanos , Lactente , Espectroscopia de Luz Próxima ao Infravermelho
20.
Br J Cancer ; 108(8): 1587-92, 2013 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-23579222

RESUMO

BACKGROUND: The objective of this study was to determine the optimal scheduling of 2.5 mg daily letrozole in neoadjuvant breast cancer patients to obtain pathological complete response (pathCR) and assess Ki-67 expression as an early predictor of response. PATIENTS AND METHODS: This single institution study comprised 120 oestrogen receptor (ER)-positive postmenopausal women with primary breast cancer (clinical stage ≥ T2, N0-1), from three sequential cohorts (cohort A of 40, cohort B of 40 and cohort C of 40 patients, respectively) based on different duration of the neoadjuvant letrozole. Biological markers such as ER, progesterone receptor, HER2 and Ki-67 expression were tested at diagnosis and at definitive surgery. RESULTS: A total of 89 patients (75.4%) achieved an objective response with 44 (37.3%) clinical CRs and 45 (38.1%) partial responses. The clinical CRs were significantly observed in cohort C (23 out of 40 patients, 57.5%) and B (16 out of 38 patients, 42.1%) compared with cohort A (5 out of 40 patients, 12.5%) (P-value for trend <0.001). Letrozole induced a similar significant reduction in Ki-67 index after treatment in all cohorts. The pathCR rate was significantly more frequent in cohort C (7 out of 40 patients, 17.5%) than in cohort A (1 out of 40 patients, 2.5%) and B (2 out of 40 patients, 5.0%) (P-value for trend <0.04). CONCLUSION: One-year neoadjuvant letrozole therapy leads to a higher pathCR rate and may be the optimal length of drug exposure.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Nitrilas/administração & dosagem , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Triazóis/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Inibidores da Aromatase/administração & dosagem , Inibidores da Aromatase/efeitos adversos , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Estudos de Coortes , Esquema de Medicação , Feminino , Humanos , Antígeno Ki-67/biossíntese , Antígeno Ki-67/metabolismo , Letrozol , Terapia Neoadjuvante , Nitrilas/efeitos adversos , Triazóis/efeitos adversos
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