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1.
Cancer Med ; 13(3): e6988, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38404120

RESUMO

BACKGROUND: Biomarkers of systemic inflammation have been shown to predict outcomes in patients with cancer of unknown primary (CUP). We sought to validate these findings in patients with confirmed CUP (cCUP) and explore their role alongside existing clinicopathological prognostic categories. PATIENTS AND METHODS: CUP oncologist from across the United Kingdom were invited to include patients with cCUP referred to their local CUP multidisciplinary team. Patient demographics, clinical, pathological and outcome data were recorded and analysed. RESULTS: Data were available for 548 patients from four CUP services. 23% (n = 124) of patients met clinicopathological criteria for favourable-risk cCUP. On multivariate analysis c-reactive protein (CRP) (p < 0.001) and the Scottish Inflammatory Prognostic Score (SIPS: combining albumin and neutrophil count) (p < 0.001) were independently predictive of survival. CRP and SIPS effectively stratified survival in patients with both favourable-risk and poor-risk cCUP based on clinicopathological features. CONCLUSIONS: Biomarkers of systemic inflammation are reliable prognostic factors in patients with cCUP, regardless of clinicopathological subgroup. We recommend that CRP or SIPS are incorporated into routine clinical assessments of patients with cCUP as a tool to aid investigation and/or treatment decision-making across all groups. Established clinicopathological factors can then be used to inform management pathways and specific systemic anticancer therapy selection.


Assuntos
Neoplasias Primárias Desconhecidas , Humanos , Prognóstico , Neoplasias Primárias Desconhecidas/diagnóstico , Neoplasias Primárias Desconhecidas/patologia , Biomarcadores , Inflamação , Proteína C-Reativa/metabolismo
2.
J Neuromuscul Dis ; 9(6): 757-764, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36245385

RESUMO

BACKGROUND: Duchenne muscular dystrophy (DMD) is an X-linked recessive neuromuscular disorder resulting from loss of dystrophin. In addition to its role in muscle, isoforms of dystrophin are expressed in different cell types of the brain, and DMD has been linked to language delays, behavioral abnormalities and learning disabilities. OBJECTIVE: To determine whether disruption of specific DMD isoforms, age, corticosteroid use, ambulation status, or country are associated with behavioral and/or learning concerns in DMD. METHODS: De-identified data were collected from the Duchenne Registry from 2007-2019. Females, patients with BMD, and those without genetic testing reports were excluded from the cohort. For the genetic analysis, patients were divided into four subgroups based on the location of their mutation and the predicted isoforms affected. Bivariate analysis was conducted using chi-square for categorical variables. Two multivariate logistic regressions were used to assess independent associations with behavioral and learning concerns, respectively, and to estimate the effect size of each variable. RESULTS: DMD mutations disrupting expression of Dp140 and Dp71 were associated with a higher likelihood of reported behavioral and learning concerns. Corticosteroid use, categorical age, and country were other factors associated with behavior and learning concerns. CONCLUSION: This data adds to our current understanding of DMD isoforms, their mutational consequence and impact on behavior and learning.


Assuntos
Distrofina , Distrofia Muscular de Duchenne , Humanos , Corticosteroides/uso terapêutico , Distrofina/genética , Distrofina/metabolismo , Distrofia Muscular de Duchenne/genética , Isoformas de Proteínas/genética , Autorrelato , Masculino
3.
Mod Pathol ; 35(4): 564-576, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34732839

RESUMO

Colorectal cancer (CRC) has one of the highest cancer incidences and mortality rates. In stage III, postoperative chemotherapy benefits <20% of patients, while more than 50% will develop distant metastases. Biomarkers for identification of patients at increased risk of disease recurrence following adjuvant chemotherapy are currently lacking. In this study, we assessed immune signatures in the tumor and tumor microenvironment (TME) using an in situ multiplexed immunofluorescence imaging and single-cell analysis technology (Cell DIVETM) and evaluated their correlations with patient outcomes. Tissue microarrays (TMAs) with up to three 1 mm diameter cores per patient were prepared from 117 stage III CRC patients treated with adjuvant fluoropyrimidine/oxaliplatin (FOLFOX) chemotherapy. Single sections underwent multiplexed immunofluorescence staining for immune cell markers (CD45, CD3, CD4, CD8, FOXP3, PD1) and tumor/cell segmentation markers (DAPI, pan-cytokeratin, AE1, NaKATPase, and S6). We used annotations and a probabilistic classification algorithm to build statistical models of immune cell types. Images were also qualitatively assessed independently by a Pathologist as 'high', 'moderate' or 'low', for stromal and total immune cell content. Excellent agreement was found between manual assessment and total automated scores (p < 0.0001). Moreover, compared to single markers, a multi-marker classification of regulatory T cells (Tregs: CD3+/CD4+FOXP3+/PD1-) was significantly associated with disease-free survival (DFS) and overall survival (OS) (p = 0.049 and 0.032) of FOLFOX-treated patients. Our results also showed that PD1- Tregs rather than PD1+ Tregs were associated with improved survival. These findings were supported by results from an independent FOLFOX-treated cohort of 191 stage III CRC patients, where higher PD1- Tregs were associated with an increase overall survival (p = 0.015) for CD3+/CD4+/FOXP3+/PD1-. Overall, compared to single markers, multi-marker classification provided more accurate quantitation of immune cell types with stronger correlations with outcomes.


Assuntos
Neoplasias Colorretais , Análise de Célula Única , Subpopulações de Linfócitos T , Biomarcadores Tumorais , Quimioterapia Adjuvante , Neoplasias Colorretais/patologia , Humanos , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Subpopulações de Linfócitos T/citologia , Microambiente Tumoral
4.
Future Healthc J ; 8(1): e101-e108, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33791486

RESUMO

BACKGROUND: Holistic approach to the clinical management pathway for malignancy of undefined primary origin (MUO)/carcinoma of unknown primary (CUP) patients remains an unmet clinical need. To address this, an MUO/CUP service was implemented during conception of a new acute oncology service (AOS). METHODOLOGY: Over a comparable 17 months' duration, patient outcomes pre-MUO/CUP service implementation was retrospectively analysed and compared prospectively with post-service implementation database. Performance measures of MUO/CUP service were compared against national recommendations. RESULTS: In the retrospective cohort (n=32), median age was 71.5 years and median length of hospital stay (LOS) was 11.25 days. In the prospective cohort (n=42), median age was 75.5 years, median LOS was 7.75 days (p=0.037). Post-service implementation, 100% patients were discussed in MUO/CUP multidisciplinary team meeting; 96% of inpatient referrals were reviewed by oncology within 24-48 hours. In the prospective group, median overall survival (OS) was 73 days vs 35 days in the retrospective group (p=0.045; hazard ratio (HR) 1.61). Out of 20 patients suitable for anti-cancer treatment in the prospective group, 85% were treated within 31 days from the decision-to-treat; 90% were treated within 62 days of referral. Within the prospective group, median OS was 214 days in the treated sub-group, compared with 44 days in patients receiving best supportive care only (p<0.0001; HR 3.19). CONCLUSION: Timely specialised input from AOS with a dedicated MUO/CUP team can achieve enhanced patient-centred and healthcare-centred outcomes, both in terms of survival and hospital stay. However, heterogeneity in both retrospective and prospective study groups, as well as discrepancies in coding, makes direct comparison between both groups challenging.

5.
Cell Metab ; 33(4): 818-832.e7, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33548171

RESUMO

Attenuating pathological angiogenesis in diseases characterized by neovascularization such as diabetic retinopathy has transformed standards of care. Yet little is known about the molecular signatures discriminating physiological blood vessels from their diseased counterparts, leading to off-target effects of therapy. We demonstrate that in contrast to healthy blood vessels, pathological vessels engage pathways of cellular senescence. Senescent (p16INK4A-expressing) cells accumulate in retinas of patients with diabetic retinopathy and during peak destructive neovascularization in a mouse model of retinopathy. Using either genetic approaches that clear p16INK4A-expressing cells or small molecule inhibitors of the anti-apoptotic protein BCL-xL, we show that senolysis suppresses pathological angiogenesis. Single-cell analysis revealed that subsets of endothelial cells with senescence signatures and expressing Col1a1 are no longer detected in BCL-xL-inhibitor-treated retinas, yielding a retina conducive to physiological vascular repair. These findings provide mechanistic evidence supporting the development of BCL-xL inhibitors as potential treatments for neovascular retinal disease.


Assuntos
Senescência Celular , Doenças Retinianas/patologia , Proteína bcl-X/metabolismo , Animais , Apoptose/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Cadeia alfa 1 do Colágeno Tipo I/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/deficiência , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Modelos Animais de Doenças , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Feminino , Flavonóis/química , Flavonóis/farmacologia , Flavonóis/uso terapêutico , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neovascularização Patológica , Doenças Retinianas/tratamento farmacológico , Doenças Retinianas/metabolismo , Tacrolimo/análogos & derivados , Tacrolimo/farmacologia , Proteína bcl-X/antagonistas & inibidores
6.
Clin Cancer Res ; 23(5): 1200-1212, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-27649552

RESUMO

Purpose: Apoptosis is essential for chemotherapy responses. In this discovery and validation study, we evaluated the suitability of a mathematical model of apoptosis execution (APOPTO-CELL) as a stand-alone signature and as a constituent of further refined prognostic stratification tools.Experimental Design: Apoptosis competency of primary tumor samples from patients with stage III colorectal cancer (n = 120) was calculated by APOPTO-CELL from measured protein concentrations of Procaspase-3, Procaspase-9, SMAC, and XIAP. An enriched APOPTO-CELL signature (APOPTO-CELL-PC3) was synthesized to capture apoptosome-independent effects of Caspase-3. Furthermore, a machine learning Random Forest approach was applied to APOPTO-CELL-PC3 and available molecular and clinicopathologic data to identify a further enhanced signature. Association of the signature with prognosis was evaluated in an independent colon adenocarcinoma cohort (TCGA COAD, n = 136).Results: We identified 3 prognostic biomarkers (P = 0.04, P = 0.006, and P = 0.0004 for APOPTO-CELL, APOPTO-CELL-PC3, and Random Forest signatures, respectively) with increasing stratification accuracy for patients with stage III colorectal cancer.The APOPTO-CELL-PC3 signature ranked highest among all features. The prognostic value of the signatures was independently validated in stage III TCGA COAD patients (P = 0.01, P = 0.04, and P = 0.02 for APOPTO-CELL, APOPTO-CELL-PC3, and Random Forest signatures, respectively). The signatures provided further stratification for patients with CMS1-3 molecular subtype.Conclusions: The integration of a systems-biology-based biomarker for apoptosis competency with machine learning approaches is an appealing and innovative strategy toward refined patient stratification. The prognostic value of apoptosis competency is independent of other available clinicopathologic and molecular factors, with tangible potential of being introduced in the clinical management of patients with stage III colorectal cancer. Clin Cancer Res; 23(5); 1200-12. ©2016 AACR.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/genética , Prognóstico , Idoso , Apoptose/genética , Caspase 3/genética , Caspase 9/genética , Neoplasias Colorretais/patologia , Intervalo Livre de Doença , Feminino , Perfilação da Expressão Gênica , Humanos , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Estadiamento de Neoplasias , Medicina de Precisão , Medição de Risco , Biologia de Sistemas
7.
Oncotarget ; 7(48): 78932-78945, 2016 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-27793046

RESUMO

c-MET and its ligand HGF are frequently overexpressed in colorectal cancer (CRC) and increased c-MET levels are found in CRC liver metastases. This study investigated the role of the HGF/c-MET axis in regulating migration/invasion in CRC, using pre-clinical models and clinical samples. Pre-clinically, we found marked upregulation of c-MET at both protein and mRNA levels in several invasive CRC cells. Down-regulation of c-MET using RNAi suppressed migration/invasion of parental and invasive CRC cells. Stimulation of CRC cells with rh-HGF or co-culture with HGF-expressing colonic myofibroblasts, resulted in significant increases in their migratory/invasive capacity. Importantly, HGF-induced c-MET activation promoted rapid downregulation of c-MET protein levels, while the MET transcript remained unaltered. Using RNA in situ hybridization (RNA ISH), we further showed that MET mRNA, but not protein levels, were significantly upregulated in tumor budding foci at the invasive front of a cohort of stage III CRC tumors (p < 0.001). Taken together, we show for the first time that transcriptional upregulation of MET is a key molecular event associated with CRC invasion and tumor budding. This data also indicates that RNA ISH, but not immunohistochemistry, provides a robust methodology to assess MET levels as a potential driving force of CRC tumor invasion and metastasis.


Assuntos
Biomarcadores Tumorais/genética , Movimento Celular , Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , Proteínas Proto-Oncogênicas c-met/genética , Transcrição Gênica , Ativação Transcricional , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Técnicas de Cocultura , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Feminino , Células HCT116 , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Miofibroblastos/metabolismo , Miofibroblastos/patologia , Invasividade Neoplásica , Estadiamento de Neoplasias , Comunicação Parácrina , Proteínas Proto-Oncogênicas c-met/metabolismo , Interferência de RNA , Transdução de Sinais , Transfecção , Regulação para Cima
8.
Clin Cancer Res ; 22(1): 230-242, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26283684

RESUMO

PURPOSE: EphA2, a member of the Eph receptor tyrosine kinases family, is an important regulator of tumor initiation, neovascularization, and metastasis in a wide range of epithelial and mesenchymal cancers; however, its role in colorectal cancer recurrence and progression is unclear. EXPERIMENTAL DESIGN: EphA2 expression was determined by immunohistochemistry in stage II/III colorectal tumors (N = 338), and findings correlated with clinical outcome. The correlation between EphA2 expression and stem cell markers CD44 and Lgr5 was examined. The role of EphA2 in migration/invasion was assessed using a panel of KRAS wild-type (WT) and mutant (MT) parental and invasive colorectal cancer cell line models. RESULTS: Colorectal tumors displayed significantly higher expression levels of EphA2 compared with matched normal tissue, which positively correlated with high CD44 and Lgr5 expression levels. Moreover, high EphA2 mRNA and protein expression were found to be associated with poor overall survival in stage II/III colorectal cancer tissues, in both univariate and multivariate analyses. Preclinically, we found that EphA2 was highly expressed in KRASMT colorectal cancer cells and that EphA2 levels are regulated by the KRAS-driven MAPK and RalGDS-RalA pathways. Moreover, EphA2 levels were elevated in several invasive daughter cell lines, and downregulation of EphA2 using RNAi or recombinant EFNA1 suppressed migration and invasion of KRASMT colorectal cancer cells. CONCLUSIONS: These data show that EpHA2 is a poor prognostic marker in stage II/III colorectal cancer, which may be due to its ability to promote cell migration and invasion, providing support for the further investigation of EphA2 as a novel prognostic biomarker and therapeutic target.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Expressão Gênica , Receptor EphA2/genética , Biomarcadores Tumorais , Linhagem Celular Tumoral , Movimento Celular/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Humanos , Estimativa de Kaplan-Meier , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Receptor EphA2/metabolismo , Reprodutibilidade dos Testes , Transdução de Sinais , Proteínas ral de Ligação ao GTP/metabolismo , Fator ral de Troca do Nucleotídeo Guanina/metabolismo , Proteínas ras/metabolismo
9.
Opt Express ; 22(7): 8574-84, 2014 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-24718229

RESUMO

We present a novel design of leakage channel fiber (LCF) that incorporates an air-hole lattice to define the modal filtering characteristics. The approach has the potential to offer single-mode, large mode area (LMA) fibers in a single-material platform with bend loss characteristics comparable to all-solid (LCFs) whilst at the same time providing significant fabrication benefits. We compare the performance of the proposed fiber with that of rod-type photonic crystal fibers (PCFs) and all-solid LCFs offering a similar effective mode area of ~1600µm(2) at 1.05µm. Our calculations show that the proposed fiber concept succeeds in combining the advantages of the use of small air holes and the larger design space of rod-type PCFs with the improved bend tolerance and greater higher order mode discrimination of all-solid LCFs, while alleviating their respective issues of rigidity and restricted material design space. We report the fabrication and experimental characterization of a first exemplar fiber, which we demonstrate offers a single-mode output with a fundamental mode area ~1440µm(2) at 1.06µm, and that can be bent down to a radius of 20cm with a bend loss of <3dB/turn. Finally we show that the proposed design concept can be adopted to achieve larger mode areas (> 3000µm(2)), albeit at the expense of reduced bend tolerance.

10.
Opt Express ; 19(22): 21295-304, 2011 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-22108980

RESUMO

The design of an all-solid, soft glass-based, large mode area Bragg fiber for effective single mode operation with mode effective area exceeding 1100 µm(2) across the wavelength range of 2-4 µm is reported. The design adopts a new strategy to induce large differential loss between the fundamental and higher order modes for effective single-mode operation within few tens of centimetres length of an otherwise multimode fiber. In addition to having the potential for the targeted application in high power laser delivery systems; complemented by a zero dispersion wavelength at 2.04 µm and rapidly developing mid-IR optical sources, the proposed fiber should also be attractive for generation of high power, single mode and less divergent supercontinuum light over this mid-IR window.

11.
J Cancer Res Ther ; 6(1): 80-1, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20479552

RESUMO

Capecitabine is an oral chemotherapeutic agent converted to 5 fluorouracil (5-FU). Neurotoxicity associated with the medication encompasses both central and peripheral nervous systems. We describe a 60 year old man with colonic carcinoma who developed diplopia due to a sixth nerve palsy following the use of capecitabine which is an orally administered prodrug of 5-FU. An MRI of brain did not reveal a space occupying lesion or vascular insult to account for his cranial nerve palsy. The sixth nerve palsy resolved spontaneously once capecitabine was withdrawn. Physicians in all walks of life are increasingly likely to come across such patients and should familiarize themselves with toxicities consequent to chemotherapy. Further research is needed to elucidate the cause of capecitabine associated neurotoxicity.


Assuntos
Doenças do Nervo Abducente/induzido quimicamente , Antimetabólitos Antineoplásicos/efeitos adversos , Desoxicitidina/análogos & derivados , Fluoruracila/análogos & derivados , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/cirurgia , Capecitabina , Quimioterapia Adjuvante/efeitos adversos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/cirurgia , Desoxicitidina/efeitos adversos , Procedimentos Cirúrgicos do Sistema Digestório , Fluoruracila/efeitos adversos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
12.
Opt Express ; 17(19): 17130-5, 2009 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-19770930

RESUMO

We present the first report on experimental observation of nonlinear spectral broadening in an all-solid photonic band gap Bragg fiber of relatively large mode area approximately 62 microm(2). The theoretically designed Bragg fiber for this specific application was fabricated by the well known MCVD technique. Nonlinear spectral broadening was observed by launching high power femtosecond pulses of 1067 nm pump wavelength. These first results indicate that fabrication of such Bragg fibers, once perfected, should potentially serve as an alternative route for realization of supercontinuum light.

13.
Opt Express ; 17(3): 1935-46, 2009 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-19189024

RESUMO

We present an improved theoretical model to estimate the minimum fiber length required for achieving a desired degree of wavefront filtering in stellar interferometry. The proposed model is based on modal analysis of the fiber and is compared with numerical results obtained through the beam propagation method as well as with reported experimental observations. We also study the effect of introducing a spatial filter at the output end of the fiber and show that the required fiber length can be reduced significantly by introducing a circular aperture of optimum radius after the fiber.

14.
Opt Express ; 16(18): 13651-6, 2008 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-18772976

RESUMO

We report the fabrication of a large mode area tellurite holey fiber from an extruded preform, with a mode area of 3000microm(2). Robust single-mode guidance at 1.55microm was confirmed by both optical measurement and numerical simulation. The propagation loss was measured as 2.9dB/m at 1.55microm. A broad and flat supercontinuum from 0.9 to 2.5microm with 6mW output was obtained with a 9cm length of this fiber.


Assuntos
Desenho Assistido por Computador , Tecnologia de Fibra Óptica/instrumentação , Vidro/química , Modelos Teóricos , Telúrio/química , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Dinâmica não Linear
15.
Opt Lett ; 30(15): 1917-9, 2005 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16092218

RESUMO

We report a novel idea for achieving highly efficient dispersion-compensating Bragg fiber by exploiting a modified quarter-wave stack condition. Our Bragg fiber yielded an average dispersion of approximately -1800 ps/(nm km) across the C band for the fundamental TE mode and an ultrahigh figure of merit of approximately 180,000 ps/(nm dB), which is at least 2 orders of magnitude higher than that of conventional dispersion-compensating fibers. The proposed methodology could be adopted for the design of a dispersion compensator across any desired wavelength range.

16.
Opt Express ; 13(2): 621-6, 2005 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-19488392

RESUMO

A Bragg fiber design with potential for applications in metro networks is proposed for the first time. The average dispersion of the designed fiber is 10 ps/km.nm in the C-band, and in view of its estimated loss being very low, such a Bragg fiber should enable ultra low-loss DWDM transmission over 100 km at 10 Gbits/s. A Bragg fiber based metro network is an attractive proposition because it would not require any amplifier and dispersion compensator for distances approximately 100 km. This should significantly reduce installation and operational cost, and complexity of a metro network.

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