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1.
Inorg Chem ; 61(6): 2846-2863, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35104130

RESUMO

Silver-indium-sulfide quantum dots (AIS QDs) have potential applications in many areas, including biomedicine. Their lack of regulated heavy metals, unlike many commercialized QDs, stands out as an advantage, but the necessity for alloyed or core-shell structures and related costly and sophisticated processes for the production of stable and high quantum yield aqueous AIS QDs are the current challenges. The present study demonstrates the one-step aqueous synthesis of simple AgInS2 QD compositions utilizing for the first time either a polyethyleneimine/2-mercaptopropionic acid (AIS-PEI/2MPA) mixture or only 2-mercaptopropionic acid (AIS-2MPA) as the stabilizing molecules, providing a AgInS2 portfolio consisting of cationic and anionic AIS QDs, respectively, and tuneable emission. Small AIS QDs with long-term stability and high quantum yields (19-23%) were achieved at a molar ratio of Ag/In/S 1/10/10 in water without any dopant or a semiconductor shell. The theranostic potential of these cationic and anionic AIS QDs was also evaluated in vitro. Non-toxic doses were determined, and fluorescence imaging potential was demonstrated. More importantly, these QDs were electrostatically loaded with zwitterionic 5-aminolevulinic acid (ALA) as a prodrug to enhance the tumor availability of ALA and to improve ALA-induced porphyrin photodynamic therapy (PDT). This is the first study investigating the influence of nanoparticle charge on ALA binding, release, and therapeutic efficacy. Surface charge was found to be more critical in cellular internalization and dark toxicity rather than drug loading and release. Both QDs provided enhanced ALA release at acidic pH but protected the prodrug at physiological pH, which is critical for tumor delivery of ALA, which suffers from low bioavailability. The PDT efficacy of the ALA-loaded AIS QDs was tested in 2D monolayers and 3D constructs of HT29 and SW480 human colon adenocarcinoma cancer cell lines. The incorporation of ALA delivery by the AIS QDs, which on their own do not cause phototoxicity, elicited significant cell death due to enhanced light-induced ROS generation and apoptotic/necrotic cell death, reducing the IC50 for ALA dramatically to about 0.1 and 0.01 mM in anionic and cationic AIS QDs, respectively. Combined with simple synthetic methods, the strong intracellular photoluminescence of AIS QDs, good biocompatibility of especially the anionic AIS QDs, and the ability to act as drug carriers for effective PDT signify that the AIS QDs, in particular AIS-2MPA, are highly promising theranostic QDs.


Assuntos
Ácido Aminolevulínico/farmacologia , Antineoplásicos/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Pontos Quânticos/química , Ácido Aminolevulínico/síntese química , Ácido Aminolevulínico/química , Ânions/síntese química , Ânions/química , Antineoplásicos/síntese química , Antineoplásicos/química , Cátions/síntese química , Cátions/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Índio/química , Imagem Óptica , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Prata/química , Sulfetos/química , Células Tumorais Cultivadas , Água/química
2.
Int J Mol Sci ; 22(8)2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33924238

RESUMO

Pancreatic cancer is a unique cancer in that up to 90% of its tumour mass is composed of a hypovascular and fibrotic stroma. This makes it extremely difficult for chemotherapies to be delivered into the core of the cancer mass. We tissue-engineered a biomimetic 3D pancreatic cancer ("tumouroid") model comprised of a central artificial cancer mass (ACM), containing MIA Paca-2 cells, surrounded by a fibrotic stromal compartment. This stromal compartment had a higher concentration of collagen type I, fibronectin, laminin, and hyaluronic acid (HA) than the ACM. The incorporation of HA was validated with alcian blue staining. Response to paclitaxel was determined in 2D MIA Paca-2 cell cultures, the ACMs alone, and in simple and complex tumouroids, in order to demonstrate drug sensitivity within pancreatic tumouroids of increasing complexity. The results showed that MIA Paca-2 cells grew into the complex stroma and invaded as cell clusters with a maximum distance of 363.7 µm by day 21. In terms of drug response, the IC50 for paclitaxel for MIA Paca-2 cells increased from 0.819 nM in 2D to 3.02 nM in ACMs and to 5.87 nM and 3.803 nM in simple and complex tumouroids respectively, indicating that drug penetration may be significantly reduced in the latter. The results demonstrate the need for biomimetic models during initial drug testing and evaluation.


Assuntos
Paclitaxel/farmacologia , Neoplasias Pancreáticas/patologia , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo , Engenharia Tecidual , Microambiente Tumoral/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos , Imunofluorescência , Humanos , Imuno-Histoquímica , Paclitaxel/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Esferoides Celulares , Células Estromais/patologia , Células Tumorais Cultivadas
3.
Br J Cancer ; 123(7): 1178-1190, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32641866

RESUMO

BACKGROUND: Cancer-associated fibroblasts (CAFs) are highly differentiated and heterogeneous cancer-stromal cells that promote tumour growth, angiogenesis and matrix remodelling. METHODS: We utilised an adapted version of a previously developed 3D in vitro model of colorectal cancer, composed of a cancer mass and the surrounding stromal compartment. We compared cancer invasion with an acellular stromal surround, a "healthy" or normal cellular stroma and a cancerous stroma. For the cancerous stroma, we incorporated six patient-derived CAF samples to study their differential effects on cancer growth, vascular network formation and remodelling. RESULTS: CAFs enhanced the distance and surface area of the invasive cancer mass whilst inhibiting vascular-like network formation. These processes correlated with the upregulation of hepatocyte growth factor (HGF), metallopeptidase inhibitor 1 (TIMP1) and fibulin-5 (FBLN5). Vascular remodelling of previously formed endothelial structures occurred through the disruption of complex networks, and was associated with the upregulation of vascular endothelial growth factor (VEGFA) and downregulation in vascular endothelial cadherin (VE-Cadherin). CONCLUSIONS: These results support, within a biomimetic 3D, in vitro framework, the direct role of CAFs in promoting cancer invasion, and their key function in driving vasculogenesis and angiogenesis.


Assuntos
Fibroblastos Associados a Câncer/fisiologia , Neoplasias Colorretais/patologia , Células Estromais/fisiologia , Linhagem Celular Tumoral , Neoplasias Colorretais/irrigação sanguínea , Progressão da Doença , Humanos , Invasividade Neoplásica , Fator A de Crescimento do Endotélio Vascular/análise , Remodelação Vascular
4.
Cell Tissue Res ; 379(3): 511-520, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31776824

RESUMO

Despite being considered present in most vascularised tissues, lymphatic vessels have not been properly shown in human adipose tissue (AT). Our goal in this study is to investigate an unanswered question in AT biology, regarding lymphatic network presence in tissue parenchyma. Using human subcutaneous (S-) and visceral (V-) AT samples with whole mount staining for lymphatic specific markers and three-dimensional imaging, we showed lymphatic capillaries and larger lymphatic vessels in the human VAT. Conversely, in the human SAT, microcirculatory lymphatic vascular structures were rarely detected and no initial lymphatics were found.


Assuntos
Tecido Adiposo/anatomia & histologia , Vasos Linfáticos/anatomia & histologia , Tecido Adiposo/irrigação sanguínea , Tecido Adiposo/fisiologia , Feminino , Humanos , Imageamento Tridimensional , Imuno-Histoquímica , Gordura Intra-Abdominal/anatomia & histologia , Gordura Intra-Abdominal/irrigação sanguínea , Gordura Intra-Abdominal/fisiologia , Vasos Linfáticos/irrigação sanguínea , Vasos Linfáticos/fisiologia , Masculino , Pessoa de Meia-Idade , Gordura Subcutânea/anatomia & histologia , Gordura Subcutânea/irrigação sanguínea , Gordura Subcutânea/fisiologia
5.
Int J Mol Sci ; 21(9)2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32366058

RESUMO

In this study we explored the efficacy of combining low dose photodynamic therapy using a porphyrin photosensitiser and dactinomycin, a commonly used chemotherapeutic agent. The studies were carried out on compressed collagen 3D constructs of two human ovarian cancer cell lines (SKOV3 and HEY) versus their monolayer counterparts. An amphiphilc photosensitiser was employed, disulfonated tetraphenylporphine, which is not a substrate for ABC efflux transporters that can mediate drug resistance. The combination treatment was shown to be effective in both monolayer and 3D constructs of both cell lines, causing a significant and synergistic reduction in cell viability. Compared to dactinomycin alone or PDT alone, higher cell kill was found using 2D monolayer culture vs. 3D culture for the same doses. In 3D culture, the combination therapy resulted in 10 and 22 times higher cell kill in SKOV3 and HEY cells at the highest light dose compared to dactinomycin monotherapy, and 2.2 and 5.5 times higher cell kill than PDT alone. The combination of low dose PDT and dactinomycin appears to be a promising way to repurpose dactinomycin and widen its therapeutic applications.


Assuntos
Antineoplásicos/farmacologia , Dactinomicina/farmacologia , Neoplasias Ovarianas/metabolismo , Fotoquimioterapia/métodos , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Feminino , Humanos
6.
PLoS Comput Biol ; 13(1): e1005259, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28125582

RESUMO

Vascularisation is a key feature of cancer growth, invasion and metastasis. To better understand the governing biophysical processes and their relative importance, it is instructive to develop physiologically representative mathematical models with which to compare to experimental data. Previous studies have successfully applied this approach to test the effect of various biochemical factors on tumour growth and angiogenesis. However, these models do not account for the experimentally observed dependency of angiogenic network evolution on growth-induced solid stresses. This work introduces two novel features: the effects of hapto- and mechanotaxis on vessel sprouting, and mechano-sensitive dynamic vascular remodelling. The proposed three-dimensional, multiscale, in-silico model of dynamically coupled angiogenic tumour growth is specified to in-vivo and in-vitro data, chosen, where possible, to provide a physiologically consistent description. The model is then validated against in-vivo data from murine mammary carcinomas, with particular focus placed on identifying the influence of mechanical factors. Crucially, we find that it is necessary to include hapto- and mechanotaxis to recapitulate observed time-varying spatial distributions of angiogenic vasculature.


Assuntos
Velocidade do Fluxo Sanguíneo , Proliferação de Células , Mecanotransdução Celular , Modelos Biológicos , Neoplasias/fisiopatologia , Neovascularização Patológica/fisiopatologia , Animais , Pressão Sanguínea , Simulação por Computador , Humanos , Neoplasias/patologia , Neovascularização Patológica/patologia , Resistência ao Cisalhamento , Estresse Mecânico , Microambiente Tumoral/fisiologia
7.
Int J Cancer ; 138(5): 1049-57, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25758607

RESUMO

Photochemical internalisation (PCI) is a technique for improving cellular delivery of certain bioactive agents which are prone to sequestration within endolysosomes. There is a wide range of agents suitable for PCI-based delivery including toxins, oligonucleotides, genes and immunoconjugates which demonstrates the versatility of this technique. The basic mechanism of PCI involves triggering release of the agent from endolysosomes within the target cells using a photosensitiser which is selectively retained with the endolysosomal membranes. Excitation of the photosensitiser by visible light leads to disruption of the membranes via photooxidative damage thereby releasing the agent into the cytosol. This treatment enables the drugs to reach their intended subcellular target more efficiently and improves their efficacy. In this review we summarise the applications of this technique with the main emphasis placed on cancer chemotherapy.


Assuntos
Citotoxinas/uso terapêutico , Neoplasias/tratamento farmacológico , Fotoquimioterapia/métodos , Animais , Antraciclinas/uso terapêutico , Portadores de Fármacos , Glicopeptídeos/uso terapêutico , Humanos , Terapia de Alvo Molecular , Fármacos Fotossensibilizantes/administração & dosagem , Proteínas Inativadoras de Ribossomos/uso terapêutico
8.
Nanotechnology ; 27(28): 285101, 2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-27255548

RESUMO

Calreticulin (CRT) is a cytoplasmic calcium-binding protein. The aim of this study was to investigate CRT presence in cancer with the use of fluorescent gold nanoclusters (AuNCs) and to explore AuNC synthesis using mercaptosuccinic acid (MSA) as a coating agent. MSA-coated AuNCs conferred well-dispersed, bio-stable, water-soluble nanoparticles with bioconjugation capacity and 800-850 nm fluorescence after broad-band excitation. Cell-viability assay revealed good AuNC tolerability. A native CRT amino-terminus corresponding peptide sequence was synthesised and used to generate rabbit site-specific antibodies. Target specificity was demonstrated with antibody blocking in colorectal and breast cancer cell models; human umbilical vein endothelial cells served as controls. We demonstrated a novel route of AuNC/MSA manufacture and CRT presence on colonic and breast cancerous cell surface. AuNCs served as fluorescent bio-probes specifically recognising surface-bound CRT. These results are promising in terms of AuNC application in cancer theranostics and CRT use as surface biomarker in human cancer.


Assuntos
Nanoestruturas , Animais , Biomarcadores Tumorais , Calreticulina , Clero , Fluorescência , Ouro , Humanos
9.
Small ; 10(19): 3954-61, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24990320

RESUMO

In order to maximize the potential of nanoparticles (NPs) in cancer imaging and therapy, their mechanisms of interaction with host tissue need to be fully understood. NP uptake is known to be dramatically influenced by the tumor microenvironment, and an imaging platform that could replicate in vivo cellular conditions would make big strides in NP uptake studies. Here, a novel NP uptake platform consisting of a tissue-engineered 3D in vitro cancer model (tumoroid), which mimics the microarchitecture of a solid cancer mass and stroma, is presented. As the tumoroid exhibits fundamental characteristics of solid cancer tissue and its cellular and biochemical parameters are controllable, it provides a real alternative to animal models. Furthermore, an X-ray fluorescence imaging system is developed to demonstrate 3D imaging of GNPs and to determine uptake efficiency within the tumoroid. This platform has implications for optimizing the targeted delivery of NPs to cells to benefit cancer diagnostics and therapy.


Assuntos
Nanopartículas/química , Neoplasias/patologia , Células 3T3 , Animais , Calibragem , Linhagem Celular Tumoral , Ouro/química , Humanos , Imageamento Tridimensional , Nanopartículas Metálicas/química , Camundongos , Microscopia Eletrônica de Transmissão , Engenharia Tecidual/métodos , Microambiente Tumoral , Raios X
10.
Cochrane Database Syst Rev ; (8): CD006575, 2013 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-23980026

RESUMO

BACKGROUND: Standard surgical training has traditionally been one of apprenticeship, where the surgical trainee learns to perform surgery under the supervision of a trained surgeon. This is time-consuming, costly, and of variable effectiveness. Training using a virtual reality simulator is an option to supplement standard training. Virtual reality training improves the technical skills of surgical trainees such as decreased time for suturing and improved accuracy. The clinical impact of virtual reality training is not known. OBJECTIVES: To assess the benefits (increased surgical proficiency and improved patient outcomes) and harms (potentially worse patient outcomes) of supplementary virtual reality training of surgical trainees with limited laparoscopic experience. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE and Science Citation Index Expanded until July 2012. SELECTION CRITERIA: We included all randomised clinical trials comparing virtual reality training versus other forms of training including box-trainer training, no training, or standard laparoscopic training in surgical trainees with little laparoscopic experience. We also planned to include trials comparing different methods of virtual reality training. We included only trials that assessed the outcomes in people undergoing laparoscopic surgery. DATA COLLECTION AND ANALYSIS: Two authors independently identified trials and collected data. We analysed the data with both the fixed-effect and the random-effects models using Review Manager 5 analysis. For each outcome we calculated the mean difference (MD) or standardised mean difference (SMD) with 95% confidence intervals based on intention-to-treat analysis. MAIN RESULTS: We included eight trials covering 109 surgical trainees with limited laparoscopic experience. Of the eight trials, six compared virtual reality versus no supplementary training. One trial compared virtual reality training versus box-trainer training and versus no supplementary training, and one trial compared virtual reality training versus box-trainer training. There were no trials that compared different forms of virtual reality training. All the trials were at high risk of bias. Operating time and operative performance were the only outcomes reported in the trials. The remaining outcomes such as mortality, morbidity, quality of life (the primary outcomes of this review) and hospital stay (a secondary outcome) were not reported. Virtual reality training versus no supplementary training: The operating time was significantly shorter in the virtual reality group than in the no supplementary training group (3 trials; 49 participants; MD -11.76 minutes; 95% CI -15.23 to -8.30). Two trials that could not be included in the meta-analysis also showed a reduction in operating time (statistically significant in one trial). The numerical values for operating time were not reported in these two trials. The operative performance was significantly better in the virtual reality group than the no supplementary training group using the fixed-effect model (2 trials; 33 participants; SMD 1.65; 95% CI 0.72 to 2.58). The results became non-significant when the random-effects model was used (2 trials; 33 participants; SMD 2.14; 95% CI -1.29 to 5.57). One trial could not be included in the meta-analysis as it did not report the numerical values. The authors stated that the operative performance of virtual reality group was significantly better than the control group. Virtual reality training versus box-trainer training: The only trial that reported operating time did not report the numerical values. In this trial, the operating time in the virtual reality group was significantly shorter than in the box-trainer group. Of the two trials that reported operative performance, only one trial reported the numerical values. The operative performance was significantly better in the virtual reality group than in the box-trainer group (1 trial; 19 participants; SMD 1.46; 95% CI 0.42 to 2.50). In the other trial that did not report the numerical values, the authors stated that the operative performance in the virtual reality group was significantly better than the box-trainer group. AUTHORS' CONCLUSIONS: Virtual reality training appears to decrease the operating time and improve the operative performance of surgical trainees with limited laparoscopic experience when compared with no training or with box-trainer training. However, the impact of this decreased operating time and improvement in operative performance on patients and healthcare funders in terms of improved outcomes or decreased costs is not known. Further well-designed trials at low risk of bias and random errors are necessary. Such trials should assess the impact of virtual reality training on clinical outcomes.


Assuntos
Simulação por Computador , Instrução por Computador/métodos , Cirurgia Geral/educação , Laparoscopia/educação , Humanos , Duração da Cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto
11.
Biomedicines ; 11(2)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36831108

RESUMO

Photochemical internalisation (PCI) is a means of achieving spatio-temporal control of cytosolic drug delivery using sub-lethal photodynamic therapy (PDT), with a photosensitiser that can be activated by non-ionising visible light. Various 3D models including those developed at our laboratory, where spheroids are grown in a compressed collagen matrix, have been used for studying anti-cancer drug effects. However, the use of a more biomimetic tumouroid model which consists of a relatively hypoxic central cancer mass surrounded by its microenvironment (stroma) has not yet been explored in either toxicity or phototoxicity studies involving PCI. Here, we examined the efficacy of PCI using a porphyrin photosensitiser and a cytotoxin (Saporin) on ovarian cancer tumouroids, with HEY ovarian cancer cells in the central cancer compartment, and HDF fibroblast cells and HUVEC endothelial cells in the surrounding stromal compartment. The efficacy was compared to tumouroids treated with either Saporin or PDT alone, or no treatment. PCI treatment was shown to be effective in the tumouroids (determined through viability assays and imaging) and caused a considerable decrease in the viability of cancer cells both within the central cancer mass and those which had migrated into the stroma, as well as a reduction in the cell density of surrounding HUVEC and HDFs. Post-treatment, the mean distance of stromal invasion by cancer cells from the original cancer mass following treatment with Saporin alone was 730 µm vs. 125 µm for PCI. PDT was also effective at reducing viability in the central cancer mass and stroma but required a higher photosensitiser dose and light dose than PCI. Tumouroids, as tissue mimics, are suitable models for interrogating multicellular events following pharmacological assault.

12.
BMJ Open ; 13(11): e074077, 2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37949629

RESUMO

INTRODUCTION: Cough as a symptom of renal cell carcinoma (RCC) was first described by Creevy in 1935, and despite one (unpublished) study suggesting it may affect 31% of these patients, as well as cough being discussed in forums for patients with kidney cancer, few clinicians are aware of this association. The cough has been described as unusual in nature, resolving rapidly after treatment with nephrectomy/embolisation but returning if the tumour recurs. METHODS AND ANALYSIS: A prospective study using a questionnaire will identify the prevalence of cough in patients with suspected or confirmed RCC attending the Specialist Centre for Kidney Cancer (London, UK). A longitudinal study in a representative sample of these patients, using EQ-5D-5L and Leicester Cough Questionnaires, together with the use of semi-structured interviews with patients, will identify the impact of cough in addition to having a diagnosis of suspected or confirmed RCC on quality of life. To investigate cough mechanisms, a pilot study using cough hypersensitivity testing will be performed on patients with RCC, with and without a cough. Clinical samples (urine, blood, phlegm and breath condensate) from patients with RCC, with and without a cough, will be collected and analysed for the presence of substances known to trigger or enhance cough and compared with the results obtained from healthy volunteers. ETHICS AND DISSEMINATION: Ethical approval has been granted (UK HR REC 22/PR/0791 dated 25/08/2022). Study outputs will be presented and published nationally and internationally at relevant conferences. This study will establish the prevalence of cough in patients with suspected or confirmed kidney cancer and support the education of clinicians to consider this diagnosis in patients with chronic cough (eg, recommending protocols to include both kidneys when investigating respiratory symptoms with chest CT scans). If substances known to trigger or enhance cough are identified and elevated in clinical samples, this research could offer potential targets for treatment for this distressing symptom. TRIAL REGISTRATION NUMBER: NIHR CRN portfolio CPMS ID:53 372.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/complicações , Carcinoma de Células Renais/diagnóstico , Tosse/diagnóstico , Tosse/epidemiologia , Tosse/etiologia , Estudos Longitudinais , Estudos Prospectivos , Qualidade de Vida , Prevalência , Projetos Piloto , Detecção Precoce de Câncer , Neoplasias Renais/complicações
13.
Int J Cancer ; 130(6): 1264-72, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21445967

RESUMO

Endothelin-1 (ET-1) is produced by and stimulates colorectal cancer cells. Fibroblasts produce tumour stroma required for cancer development. We investigated whether ET-1 stimulated processes involved in tumour stroma production by colonic fibroblasts. Primary human fibroblasts, isolated from normal tissues adjacent to colon cancers, were cultured with or without ET-1 and its antagonists. Cellular proliferation, migration and contraction were measured. Expression of enzymes involved in tumour stroma development and alterations in gene transcription were determined by Western blotting and genome microarrays. ET-1 stimulated proliferation, contraction and migration (p < 0.01 v control) and the expression of matrix degrading enzymes TIMP-1 and MMP-2, but not MMP-3. ET-1 upregulated genes for profibrotic growth factors and receptors, signalling molecules, actin modulators and extracellular matrix components. ET-1 stimulated colonic fibroblast cellular processes in vitro that are involved in developing tumour stroma. Upregulated genes were consistent with these processes. By acting as a strong stimulus for tumour stroma creation, ET-1 is proposed as a target for adjuvant cancer therapy.


Assuntos
Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Endotelina-1/metabolismo , Fibroblastos/metabolismo , Fibroblastos/patologia , Actinas/metabolismo , Processos de Crescimento Celular/fisiologia , Movimento Celular/fisiologia , Neoplasias do Colo/genética , Endotelina-1/antagonistas & inibidores , Endotelina-1/genética , Endotelina-1/farmacologia , Matriz Extracelular/metabolismo , Fibroblastos/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Receptor de Endotelina A/genética , Receptor de Endotelina A/metabolismo , Receptor de Endotelina B/genética , Receptor de Endotelina B/metabolismo , Receptores de Fatores de Crescimento/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Células Tumorais Cultivadas , Regulação para Cima/genética
14.
Cancer Med ; 11(15): 2957-2968, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35343093

RESUMO

BACKGROUND: Colorectal cancer (CRC) is the second cause of cancer death worldwide. The role of circulating microvesicles as a screening tool is a novel, yet effective approach that warrants prioritised research. METHODS: In a two-gate diagnostic accuracy study, 35 patients with benign colorectal polyps (BCRP) (n = 16) and colorectal cancer (CRC) (n = 19) were compared to 17 age-matched healthy controls. Total annexin-V positive microvesicles and sub-populations positive for selected biomarkers relevant to bowel neoplasm were evaluated in patients' plasma using flow cytometry. Statistical methods including factor analysis utilising two component factors were performed to obtain optimal diagnostic accuracy of microvesicles in identifying patients with colorectal neoplasms. RESULTS: Total plasma microvesicles, and sub-populations positive for CD31, CD42a, CD31+/CD42a-, EPHB2, ICAM and LGR5 (component factor-1) were able to identify patients with BCRP and CRC with a receiver operator curve (AUC) accuracy of a 100% (95% CI: 100%-100%) and 95% (95% CI: 88%-100%), respectively. To identify patients with BCRP, a cut-off point value of component factor-1761 microvesicles/µl demonstrated a 100% sensitivity, specificity and negative predictive value (NPV) and a 93% positive predictive value (PPV). To identify patients with CRC, a cut-off value of component factor-1 3 439 microvesicles/µl demonstrated a 100% sensitivity, specificity and NPV and a 65% PPV. CEA+ microvesicles sub-population were significantly (p < 0.02) higher in CRC in comparison to BCRP. CONCLUSIONS: Microvesicles as biomarkers for the early and accurate detection of CRC is a simple and effective tool that yields a potential breakthrough in clinical management.


Assuntos
Neoplasias Colorretais , Proteínas de Neoplasias , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Biomarcadores , Biomarcadores Tumorais , Neoplasias Colorretais/diagnóstico , Humanos , Programas de Rastreamento
15.
Clin Epigenetics ; 14(1): 98, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35915507

RESUMO

Histone 3 lysine 27 (H3K27) demethylation constitutes an important epigenetic mechanism of gene activation. It is mediated by the Jumonji C domain-containing lysine demethylases KDM6A and KDM6B, both of which have been implicated in a wide myriad of diseases, including blood and solid tumours, autoimmune and inflammatory disorders, and infectious diseases. Here, we review and summarise the pre-clinical evidence, both in vitro and in vivo, in support of the therapeutic potential of inhibiting H3K27-targeting demethylases, with a focus on the small-molecule inhibitor GSK-J4. In malignancies, KDM6A/B inhibition possesses the ability to inhibit proliferation, induce apoptosis, promote differentiation, and heighten sensitivity to currently employed chemotherapeutics. KDM6A/B inhibition also comprises a potent anti-inflammatory approach in inflammatory and autoimmune disorders associated with inappropriately exuberant inflammatory and autoimmune responses, restoring immunological homeostasis to inflamed tissues. With respect to infectious diseases, KDM6A/B inhibition can suppress the growth of infectious pathogens and attenuate the immunopathology precipitated by these pathogens. The pre-clinical in vitro and in vivo data, summarised in this review, suggest that inhibiting H3K27 demethylases holds immense therapeutic potential in many diseases.


Assuntos
Histonas , Neoplasias , Metilação de DNA , Epigênese Genética , Histona Desmetilases/genética , Histonas/metabolismo , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Lisina/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética
16.
J Cell Commun Signal ; 16(4): 637-648, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35102500

RESUMO

Recent advancements in 3D in vitro culture have allowed for the development of cancer tissue models which accurately recapitulate the tumour microenvironment. Consequently, there has been increased innovation in therapeutic drug screening. While organoid cultures show great potential, they are limited by the time scale of their growth in vitro and the dependence upon commercial matrices, such as Matrigel, which do not allow for manipulations of their composition or mechanical properties. Here, we show a straightforward approach for the isolation and culture of primary human renal carcinoma cells and matched non-affected kidney. This approach does not require any specific selection for cancer cells, and allows for their direct culture in amenable 3D collagen-based matrices, with the preservation of cancer cells as confirmed by NGS sequencing. This method allows for culture of patient-derived cancer cells in 3D microenvironment, which can be used for downstream experimentation such as investigation of cell-matrix interaction or drug screening.

17.
Nanoscale ; 13(35): 14879-14899, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34533177

RESUMO

Colorectal cancer (CRC) has a poor prognosis and urgently needs better therapeutic approaches. 5-Aminolevulinic acid (ALA) induced protoporphyrin IX (PpIX) based photodynamic therapy (PDT) is already used in the clinic for several cancers but not yet well investigated for CRC. Currently, systemic administration of ALA offers a limited degree of tumour selectivity, except for intracranial tumours, limiting its wider use in the clinic. The combination of effective ALA-PDT and chemotherapy may provide a promising alternative approach for CRC treatment. Herein, theranostic Ag2S quantum dots (AS-2MPA) optically trackable in near-infrared (NIR), conjugated with endothelial growth factor receptor (EGFR) targeting Cetuximab (Cet) and loaded with ALA for PDT monotherapy or ALA/5-fluorouracil (5FU) for the combination therapy are proposed for enhanced treatment of EGFR(+) CRC. AS-2MPA-Cet exhibited excellent targeting of the high EGFR expressing cells and showed a strong intracellular signal for NIR optical detection in a comparative study performed on SW480, HCT116, and HT29 cells, which exhibit high, medium and low EGFR expression, respectively. Targeting provided enhanced uptake of the ALA loaded nanoparticles by strong EGFR expressing cells and formation of higher levels of PpIX. Cells also differ in their efficiency to convert ALA to PpIX, and SW480 was the best, followed by HT29, while HCT116 was determined as unsuitable for ALA-PDT. The therapeutic efficacy was evaluated in 2D cell cultures and 3D spheroids of SW480 and HT29 cells using AS-2MPA with either electrostatically loaded, hydrazone or amide linked ALA to achieve different levels of pH or enzyme sensitive release. Most effective phototoxicity was observed in SW480 cells using AS-2MPA-ALA-electrostatic-Cet due to enhanced uptake of the particles, fast ALA release and effective ALA-to-PpIX conversion. Targeted delivery reduced the effective ALA concentration significantly which was further reduced with codelivery of 5FU. Delivery of ALA via covalent linkages was also effective for PDT, but required a longer incubation time for the release of ALA in therapeutic doses. Phototoxicity was correlated with high levels of reactive oxygen species (ROS) and apoptotic/necrotic cell death. Hence, both AS-2MPA-ALA-Cet based PDT and AS-2MPA-ALA-Cet-5FU based chemo/PDT combination therapy coupled with strong NIR tracking of the nanoparticles demonstrate an exceptional therapeutic effect on CRC cells and excellent potential for synergistic multistage tumour targeting therapy.


Assuntos
Neoplasias Colorretais , Fotoquimioterapia , Pontos Quânticos , Ácido Aminolevulínico/farmacologia , Linhagem Celular Tumoral , Cetuximab/farmacologia , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/tratamento farmacológico , Humanos , Imagem Óptica , Fármacos Fotossensibilizantes/farmacologia , Protoporfirinas
18.
PeerJ ; 9: e10673, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33569250

RESUMO

BACKGROUND: Only a small proportion of preclinical research (research performed in animal models prior to clinical trials in humans) translates into clinical benefit in humans. Possible reasons for the lack of translation of the results observed in preclinical research into human clinical benefit include the design, conduct, and reporting of preclinical studies. There is currently no formal domain-based assessment of the clinical relevance of preclinical research. To address this issue, we have developed a tool for the assessment of the clinical relevance of preclinical studies, with the intention of assessing the likelihood that therapeutic preclinical findings can be translated into improvement in the management of human diseases. METHODS: We searched the EQUATOR network for guidelines that describe the design, conduct, and reporting of preclinical research. We searched the references of these guidelines to identify further relevant publications and developed a set of domains and signalling questions. We then conducted a modified Delphi-consensus to refine and develop the tool. The Delphi panel members included specialists in evidence-based (preclinical) medicine specialists, methodologists, preclinical animal researchers, a veterinarian, and clinical researchers. A total of 20 Delphi-panel members completed the first round and 17 members from five countries completed all three rounds. RESULTS: This tool has eight domains (construct validity, external validity, risk of bias, experimental design and data analysis plan, reproducibility and replicability of methods and results in the same model, research integrity, and research transparency) and a total of 28 signalling questions and provides a framework for researchers, journal editors, grant funders, and regulatory authorities to assess the potential clinical relevance of preclinical animal research. CONCLUSION: We have developed a tool to assess the clinical relevance of preclinical studies. This tool is currently being piloted.

19.
Sci Rep ; 10(1): 12020, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32694700

RESUMO

3D laboratory models of cancer are designed to recapitulate the biochemical and biophysical characteristics of the tumour microenvironment and aim to enable studies of cancer, and new therapeutic modalities, in a physiologically-relevant manner. We have developed an in vitro 3D model comprising a central high-density mass of breast cancer cells surrounded by collagen type-1 and we incorporated fluid flow and pressure. We noted significant changes in cancer cell behaviour using this system. MDA-MB231 and SKBR3 breast cancer cells grown in 3D downregulated the proliferative marker Ki67 (P < 0.05) and exhibited decreased response to the chemotherapeutic agent doxorubicin (DOX) (P < 0.01). Mesenchymal markers snail and MMP14 were upregulated in cancer cells maintained in 3D (P < 0.001), cadherin-11 was downregulated (P < 0.001) and HER2 increased (P < 0.05). Cells maintained in 3D under fluid flow exhibited a further reduction in response to DOX (P < 0.05); HER2 and Ki67 levels were also attenuated. Fluid flow and pressure was associated with reduced cell viability and decreased expression levels of vimentin. In summary, aggressive cancer cell behaviour and reduced drug responsiveness was observed when breast cancer cells were maintained in 3D under fluid flow and pressure. These observations are relevant for future developments of 3D in vitro cancer models and organ-on-a-chip initiatives.


Assuntos
Antineoplásicos/farmacologia , Técnicas de Cultura de Células/métodos , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Fenótipo , Neoplasias de Mama Triplo Negativas/patologia , Caderinas/análise , Caderinas/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Antígeno Ki-67/análise , Antígeno Ki-67/metabolismo , Metaloproteinase 14 da Matriz/análise , Metaloproteinase 14 da Matriz/metabolismo , Modelos Biológicos , Receptor ErbB-2/análise , Receptor ErbB-2/metabolismo , Fatores de Transcrição da Família Snail/análise , Fatores de Transcrição da Família Snail/metabolismo , Microambiente Tumoral , Vimentina/análise , Vimentina/metabolismo
20.
J Cancer Res Clin Oncol ; 146(11): 2861-2870, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32772171

RESUMO

PURPOSE: IGF-1Ec is an isoform of Insulin-like growth factor 1 (IGF-1) and has recently been identified to be overexpressed in cancers including prostate and neuroendocrine tumours. The aim of this paper is to investigate the expression of IGF-1Ec in colorectal cancer and polyps compared to normal colon tissues and its association with recurrent disease using semi-quantitative immunohistochemistry. METHODS: Immunohistochemistry for IGF-1Ec expression was performed for colorectal cancer, colorectal polyps and normal colonic tissues. The quantification of IGF-1Ec expression was performed with the use of Image J software and the IHC profiler plugin. Following ethics approval from the National Research Ethics Service (Reference 11/LO/1521), clinical information including recurrent disease on follow-up was collected for patients with colorectal cancer. RESULTS: Immunohistochemistry was performed in 16 patients with colorectal cancer and 11 patients with colonic polyps and compared to normal colon tissues and prostate adenocarcinoma (positive control) tissues. Significantly increased expression of IGF-1Ec was demonstrated in colorectal cancer (p < 0.001) and colorectal polyps (p < 0.05) compared to normal colonic tissues. Colonic adenomas with high-grade dysplasia had significantly higher expression of IGF-1Ec compared to low-grade dysplastic adenomas (p < 0.001). Colorectal cancers without lymph node metastases at the time of presentation had significantly higher IGF-1Ec expression compared to lymph node-positive disease (p < 0.05). No correlation with recurrent disease was identified with IGF-1Ec expression. CONCLUSION: IGF-1Ec is significantly overexpressed in colorectal cancer and polyps compared to normal colon tissues offering a potential target to improve colonoscopic identification of colorectal polyps and cancer and intraoperative identification of colorectal tumours.


Assuntos
Pólipos Adenomatosos/diagnóstico , Pólipos do Colo/diagnóstico , Neoplasias Colorretais/diagnóstico , Fator de Crescimento Insulin-Like I/metabolismo , Pólipos Adenomatosos/metabolismo , Pólipos Adenomatosos/patologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Pólipos do Colo/metabolismo , Pólipos do Colo/patologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Feminino , Humanos , Imuno-Histoquímica/métodos , Fator de Crescimento Insulin-Like I/análise , Masculino
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