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1.
BMC Infect Dis ; 24(1): 552, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38831406

RESUMEN

BACKGROUND: Persistent infections with high-risk human papillomavirus (hrHPV) can cause cervical squamous intraepithelial lesions (SIL) that may progress to cancer. The cervicovaginal microbiome (CVM) correlates with SIL, but the temporal composition of the CVM after hrHPV infections has not been fully clarified. METHODS: To determine the association between the CVM composition and infection outcome, we applied high-resolution microbiome profiling using the circular probe-based RNA sequencing technology on a longitudinal cohort of cervical smears obtained from 141 hrHPV DNA-positive women with normal cytology at first visit, of whom 51 were diagnosed by cytology with SIL six months later. RESULTS: Here we show that women with a microbial community characterized by low diversity and high Lactobacillus crispatus abundance at both visits exhibit low risk to SIL development, while women with a microbial community characterized by high diversity and Lactobacillus depletion at first visit have a higher risk of developing SIL. At the level of individual species, we observed that a high abundance for Gardnerella vaginalis and Atopobium vaginae at both visits associate with SIL outcomes. These species together with Dialister micraerophilus showed a moderate discriminatory power for hrHPV infection progression. CONCLUSIONS: Our results suggest that the CVM can potentially be used as a biomarker for cervical disease and SIL development after hrHPV infection diagnosis with implications on cervical cancer prevention strategies and treatment of SIL.


Asunto(s)
Cuello del Útero , Microbiota , Infecciones por Papillomavirus , Vagina , Humanos , Femenino , Estudios Longitudinales , Vagina/microbiología , Vagina/virología , Infecciones por Papillomavirus/virología , Infecciones por Papillomavirus/microbiología , Adulto , Cuello del Útero/microbiología , Cuello del Útero/virología , Persona de Mediana Edad , Papillomaviridae/genética , Papillomaviridae/aislamiento & purificación , Papillomaviridae/clasificación , Adulto Joven , Neoplasias del Cuello Uterino/virología , Neoplasias del Cuello Uterino/microbiología , Frotis Vaginal
2.
Angew Chem Int Ed Engl ; 62(24): e202300511, 2023 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-37083071

RESUMEN

We describe here a near infrared light-responsive elastin-like peptide (ELP)-based targeted nanoparticle (NP) that can rapidly switch its size from 120 to 25 nm upon photo-irradiation. Interestingly, the targeting function, which is crucial for effective cargo delivery, is preserved after transformation. The NPs are assembled from (targeted) diblock ELP micelles encapsulating photosensitizer TT1-monoblock ELP conjugates. Methionine residues in this monoblock are photo-oxidized by singlet oxygen generated from TT1, turning the ELPs hydrophilic and thus trigger NP dissociation. Phenylalanine residues from the diblocks then interact with TT1 via π-π stacking, inducing the re-formation of smaller NPs. Due to their small size and targeting function, the NPs penetrate deeper in spheroids and kill cancer cells more efficiently compared to the larger ones. This work could contribute to the design of "smart" nanomedicines with deeper penetration capacity for effective anticancer therapies.


Asunto(s)
Elastina , Nanopartículas , Elastina/química , Péptidos/química , Nanopartículas/química , Micelas
3.
BMC Med ; 20(1): 206, 2022 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-35676700

RESUMEN

BACKGROUND: Because most cervical cancers are caused by high-risk human papillomaviruses (hrHPVs), cervical cancer prevention programs increasingly employ hrHPV testing as a primary test. The high sensitivity of HPV tests is accompanied by low specificity, resulting in high rates of overdiagnosis and overtreatment. Targeted circular probe-based RNA next generation sequencing (ciRNAseq) allows for the quantitative detection of RNAs of interest with high sequencing depth. Here, we examined the potential of ciRNAseq-testing on cervical scrapes to identify hrHPV-positive women at risk of having or developing high-grade cervical intraepithelial neoplasia (CIN). METHODS: We performed ciRNAseq on 610 cervical scrapes from the Dutch cervical cancer screening program to detect gene expression from 15 hrHPV genotypes and from 429 human genes. Differentially expressed hrHPV- and host genes in scrapes from women with outcome "no CIN" or "CIN2+" were identified and a model was built to distinguish these groups. RESULTS: Apart from increasing percentages of hrHPV oncogene expression from "no CIN" to high-grade cytology/histology, we identified genes involved in cell cycle regulation, tyrosine kinase signaling pathways, immune suppression, and DNA repair being expressed at significantly higher levels in scrapes with high-grade cytology and histology. Machine learning using random forest on all the expression data resulted in a model that detected 'no CIN' versus CIN2+ in an independent data set with sensitivity and specificity of respectively 85 ± 8% and 72 ± 13%. CONCLUSIONS: CiRNAseq on exfoliated cells in cervical scrapes measures hrHPV-(onco)gene expression and host gene expression in one single assay and in the process identifies HPV genotype. By combining these data and applying machine learning protocols, the risk of CIN can be calculated. Because ciRNAseq can be performed in high-throughput, making it cost-effective, it can be a promising screening technology to stratify women at risk of CIN2+. Further increasing specificity by model improvement in larger cohorts is warranted.


Asunto(s)
Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Detección Precoz del Cáncer/métodos , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Papillomaviridae/genética , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/genética , ARN , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/genética , Frotis Vaginal
4.
BMC Biol ; 19(1): 267, 2021 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-34915863

RESUMEN

BACKGROUND: The cervicovaginal microbiome (CVM) plays a significant role in women's cervical health and disease. Microbial alterations at the species level and characteristic community state types (CST) have been associated with acquisition and persistence of high-risk human papillomavirus (hrHPV) infections that may result in progression of cervical lesions to malignancy. Current sequencing methods, especially most commonly used multiplex 16S rRNA gene sequencing, struggle to fully clarify these changes because they generally fail to provide sufficient taxonomic resolution to adequately perform species-level associative studies. To improve CVM species designation, we designed a novel sequencing tool targeting microbes at the species taxonomic rank and examined its potential for profiling the CVM. RESULTS: We introduce an accessible and practical circular probe-based RNA sequencing (CiRNAseq) technology with the potential to profile and quantify the CVM. In vitro and in silico validations demonstrate that CiRNAseq can distinctively detect species in a mock mixed microbial environment, with the output data reflecting its ability to estimate microbes' abundance. Moreover, compared to 16S rRNA gene sequencing, CiRNAseq provides equivalent results but with improved sequencing sensitivity. Analyses of a cohort of cervical smears from hrHPV-negative women versus hrHPV-positive women with high-grade cervical intraepithelial neoplasia confirmed known differences in CST occurring in the CVM of women with hrHPV-induced lesions. The technique also revealed variations in microbial diversity and abundance in the CVM of hrHPV-positive women when compared to hrHPV-negative women. CONCLUSIONS: CiRNAseq is a promising tool for studying the interplay between the CVM and hrHPV in cervical carcinogenesis. This technology could provide a better understanding of cervicovaginal CST and microbial species during health and disease, prompting the discovery of biomarkers, additional to hrHPV, that can help detect high-grade cervical lesions.


Asunto(s)
Microbiota , Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Femenino , Humanos , Microbiota/genética , Papillomaviridae/genética , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/diagnóstico , ARN Ribosómico 16S/genética , Neoplasias del Cuello Uterino/complicaciones , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/genética
5.
Mod Pathol ; 33(4): 748-757, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31537894

RESUMEN

Nearly all cervical cancers are initiated by a persistent infection with one of the high-risk human papillomaviruses (high-risk HPV). High-risk HPV DNA testing is highly sensitive but cannot distinguish between active, productive infections and dormant infections or merely deposited virus. A solution for this shortcoming may be the detection of transcriptional activity of viral oncogenes instead of mere presence of high-risk HPVs. In this study, fresh-frozen cervical tissues (n = 22) were subjected to high-risk HPV DNA detection using the line probe assay and to targeted RNA next-generation sequencing using single-molecule molecular inversion probes. Targeted RNA sequencing was applied for (1) RNA-based genotyping of high-risk HPV, giving information on specific HPV-subtype (2) discrimination of E2, E6, and E7 transcripts and (3) discovery of possible non-HPV cancer biomarkers. Data were analyzed using computational biology. Targeted RNA sequencing enabled reliable genotyping of high-risk HPV subtypes and allowed quantitative detection of E2, E6, and E7 viral gene expression, thereby discriminating cervical lesions from normal cervical tissues. Moreover, targeted RNA sequencing identified possible cervical cancer biomarkers other than high-risk HPV. Interestingly, targeted RNA sequencing also provided high-quality transcription profiles from cervical scrape samples, even after 1 week of dry storage or storage in Preservcyt fixative. This proof of concept study shows that targeted RNA sequencing can be used for high-risk HPV genotyping and simultaneous detection of high-risk HPV gene activity. Future studies are warranted to investigate the potential of targeted RNA sequencing for risk assessment for the development of cervical lesions, based on molecular analysis of cervical scrapes.


Asunto(s)
Biomarcadores de Tumor/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Pruebas de ADN del Papillomavirus Humano , Papillomaviridae/genética , Infecciones por Papillomavirus/diagnóstico , ARN Viral/genética , Análisis de Secuencia de ARN , Neoplasias del Cuello Uterino/diagnóstico , Femenino , Genotipo , Humanos , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/virología , Valor Predictivo de las Pruebas , Prueba de Estudio Conceptual , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Manejo de Especímenes , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/virología
6.
FASEB J ; 33(1): 557-571, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30001166

RESUMEN

Diffuse gliomas often carry point mutations in isocitrate dehydrogenase ( IDH1mut), resulting in metabolic stress. Although IDHmut gliomas are difficult to culture in vitro, they thrive in the brain via diffuse infiltration, suggesting brain-specific tumor-stroma interactions that can compensate for IDH-1 deficits. To elucidate the metabolic adjustments in clinical IDHmut gliomas that contribute to their malignancy, we applied a recently developed method of targeted quantitative RNA next-generation sequencing to 66 clinical gliomas and relevant orthotopic glioma xenografts, with and without the endogenous IDH-1R132H mutation. Datasets were analyzed in R using Manhattan plots to calculate distance between expression profiles, Ward's method to perform unsupervised agglomerative clustering, and the Mann Whitney U test and Fisher's exact tests for supervised group analyses. The significance of transcriptome data was investigated by protein analysis, in situ enzymatic activity mapping, and in vivo magnetic resonance spectroscopy of orthotopic IDH1mut- and IDHwt-glioma xenografts. Gene set enrichment analyses of clinical IDH1mut gliomas strongly suggest a role for catabolism of lactate and the neurotransmitter glutamate, whereas, in IDHwt gliomas, processing of glucose and glutamine are the predominant metabolic pathways. Further evidence of the differential metabolic activity in these cancers comes from in situ enzymatic mapping studies and preclinical in vivo magnetic resonance spectroscopy imaging. Our data support an evolutionary model in which IDHmut glioma cells exist in symbiosis with supportive neuronal cells and astrocytes as suppliers of glutamate and lactate, possibly explaining the diffuse nature of these cancers. The dependency on glutamate and lactate opens the way for novel approaches in the treatment of IDHmut gliomas.-Lenting, K., Khurshed, M., Peeters, T. H., van den Heuvel, C. N. A. M., van Lith, S. A. M., de Bitter, T., Hendriks, W., Span, P. N., Molenaar, R. J., Botman, D., Verrijp, K., Heerschap, A., ter Laan, M., Kusters, B., van Ewijk, A., Huynen, M. A., van Noorden, C. J. F., Leenders, W. P. J. Isocitrate dehydrogenase 1-mutated human gliomas depend on lactate and glutamate to alleviate metabolic stress.


Asunto(s)
Neoplasias Encefálicas/patología , Glioma/patología , Ácido Glutámico/metabolismo , Isocitrato Deshidrogenasa/genética , Ácido Láctico/metabolismo , Mutación , Estrés Fisiológico , 4-Aminobutirato Transaminasa/genética , 4-Aminobutirato Transaminasa/metabolismo , Animales , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Glioma/genética , Glioma/metabolismo , Glutamato Deshidrogenasa/genética , Glutamato Deshidrogenasa/metabolismo , Glutaminasa/genética , Glutaminasa/metabolismo , Humanos , Isocitrato Deshidrogenasa/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Invasividad Neoplásica , Succionato-Semialdehído Deshidrogenasa/genética , Succionato-Semialdehído Deshidrogenasa/metabolismo , Transcriptoma , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
7.
Am J Pathol ; 187(5): 940-953, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28284719

RESUMEN

Glioblastomas (GBMs) are malignant tumors characterized by their vascularity and invasive capabilities. Antiangiogenic therapy (AAT) is a treatment option that targets GBM-associated vasculature to mitigate the growth of GBMs. However, AAT demonstrates transient effects because many patients eventually develop resistance to this treatment. Several recent studies attempt to explain the molecular and biochemical basis of resistance to AAT in GBM patients. Experimental investigations suggest that the induction of extensive intratumoral hypoxia plays a key role in GBM escape from AAT. In this review, we examine AAT resistance in GBMs, with an emphasis on six potential hypoxia-mediated mechanisms: enhanced invasion and migration, including increased expression of matrix metalloproteinases and activation of the c-MET tyrosine kinase pathway; shifts in cellular metabolism, including up-regulation of hypoxia inducible factor-1α's downstream processes and the Warburg effect; induction of autophagy; augmentation of GBM stem cell self-renewal; possible implications of GBM-endothelial cell transdifferentiation; and vasoformative responses, including vasculogenesis, alternative angiogenic pathways, and vascular mimicry. Juxtaposing recent studies on well-established resistance pathways with that of emerging mechanisms highlights the overall complexity of GBM treatment resistance while also providing direction for further investigation.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Glioblastoma/tratamiento farmacológico , Hipoxia Tumoral , Autofagia/efectos de los fármacos , Autofagia/fisiología , Bevacizumab/uso terapéutico , Encéfalo/metabolismo , Neoplasias Encefálicas/metabolismo , Hipoxia de la Célula/efectos de los fármacos , Transformación Celular Neoplásica/efectos de los fármacos , Resistencia a Antineoplásicos , Glioblastoma/metabolismo , Humanos , Invasividad Neoplásica , Células Madre Neoplásicas/fisiología , Neovascularización Patológica/prevención & control , Fosforilación/fisiología , Proteínas Tirosina Quinasas Receptoras/metabolismo
8.
Nutr Cancer ; 70(3): 317-333, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29570984

RESUMEN

The review discusses the effects of Epigallocatechin-3-gallate Gallate (EGCG) on glioma as a basis for future research on clinical application of EGCG. Epidemiological studies on the effects of green tea or EGCG on the risk of glioma is inconclusive due to the limited number of studies, the inclusion of all tea types in these studies, and the focus on caffeine rather than EGCG. In vivo experiments using EGCG monotherapy are inconclusive. Nevertheless, EGCG induces cell death, prevents cellular proliferation, and limits invasion in multiple glioma cell lines. Furthermore, EGCG enhances the efficacy of anti-glioma therapies, including irradiation, temozolomide, carmustine, cisplatin, tamoxifen, and TNF-related apoptosis-inducing ligand, but reduces the effect of bortezomib. Pro-drugs, co-treatment, and encapsulation are being investigated to enhance clinical applicability of EGCG. Mechanisms of actions of EGCG have been partly elucidated. EGCG has both anti-oxidant and oxidant properties. EGCG inhibits pro-survival proteins, such as telomerase, survivin, GRP78, PEA15, and P-gp. EGCG inhibits signaling of PDGFR, IGF-1R, and 67LR. EGCG reduces invasiveness of cancer cells by inhibiting the activities of various metalloproteinases, cytokines, and chemokines. Last, EGCG inhibits some NADPH-producing enzymes, thus disturbing redox status and metabolism of glioma cells. In conclusion, EGCG may be a suitable adjuvant to potentiate anti-glioma therapies.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Catequina/análogos & derivados , Neoplasias del Sistema Nervioso Central/tratamiento farmacológico , Glioma/tratamiento farmacológico , Té/química , Animales , Anticarcinógenos/farmacología , Antineoplásicos Fitogénicos/farmacocinética , Catequina/farmacocinética , Catequina/farmacología , Proliferación Celular/efectos de los fármacos , Neoplasias del Sistema Nervioso Central/patología , Neoplasias del Sistema Nervioso Central/terapia , Terapia Combinada , Chaperón BiP del Retículo Endoplásmico , Estudios Epidemiológicos , Glioma/patología , Glioma/terapia , Humanos , Neoplasias Experimentales/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos
9.
Molecules ; 23(2)2018 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-29439552

RESUMEN

Proper control of the phosphotyrosine content in signal transduction proteins is essential for normal cell behavior and is lost in many pathologies. Attempts to normalize aberrant tyrosine phosphorylation levels in disease states currently involve either the application of small compounds that inhibit tyrosine kinases (TKs) or the addition of growth factors or their mimetics to boost receptor-type TK activity. Therapies that target the TK enzymatic counterparts, the multi-enzyme family of protein tyrosine phosphatases (PTPs), are still lacking despite their undisputed involvement in human diseases. Efforts to pharmacologically modulate PTP activity have been frustrated by the conserved structure of the PTP catalytic core, providing a daunting problem with respect to target specificity. Over the years, however, many different protein interaction-based regulatory mechanisms that control PTP activity have been uncovered, providing alternative possibilities to control PTPs individually. Here, we review these regulatory principles, discuss existing biologics and proteinaceous compounds that affect PTP activity, and mention future opportunities to drug PTPs via these regulatory concepts.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Neoplasias Encefálicas/tratamiento farmacológico , Inhibidores Enzimáticos/farmacología , Glioblastoma/tratamiento farmacológico , Proteínas Tirosina Fosfatasas/antagonistas & inhibidores , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Animales , Neoplasias Encefálicas/enzimología , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Dominio Catalítico , Inhibidores Enzimáticos/química , Regulación Neoplásica de la Expresión Génica , Glioblastoma/enzimología , Glioblastoma/genética , Glioblastoma/patología , Humanos , Modelos Moleculares , Fosfotirosina/química , Fosfotirosina/metabolismo , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Dominios y Motivos de Interacción de Proteínas , Proteínas Tirosina Fosfatasas/química , Proteínas Tirosina Fosfatasas/genética , Proteínas Tirosina Fosfatasas/metabolismo , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/metabolismo , Transducción de Señal
10.
Chembiochem ; 18(24): 2390-2394, 2017 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-28994180

RESUMEN

Overexpression of (mutated) receptor tyrosine kinases is a characteristic of many aggressive tumors, and induction of receptor uptake has long been recognized as a therapeutic modality. A conjugate of a synthetically produced cell-penetrating peptide (CPP), corresponding to amino acids 38-59 of human lactoferrin, and the recombinant llama single-domain antibody (VHH) 7D12, which binds the human epidermal growth factor receptor (EGFR), was generated by sortase A mediated transpeptidation. The conjugate blocks EGF-mediated EGFR activation with higher efficacy than that of both modalities alone; a phenomenon that is caused by both effective receptor blockade and internalization. Thus, the VHH-CPP conjugate shows a combination of activities that implement a highly powerful new design principle to block receptor activation by its clearance from the cell surface.


Asunto(s)
Péptidos de Penetración Celular/farmacología , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/inmunología , Inmunoconjugados/farmacología , Péptidos de Penetración Celular/inmunología , Endocitosis , Humanos , Inmunoconjugados/uso terapéutico , Lactoferrina/inmunología , Fragmentos de Péptidos/inmunología
11.
Histochem Cell Biol ; 148(4): 395-406, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28825130

RESUMEN

Diffuse invasion of glioma cells into the brain parenchyma leads to nonresectable brain tumors and poor prognosis of glioma disease. In vivo, glioma cells can adopt a range of invasion strategies and routes, by moving as single cells, collective strands and multicellular networks along perivascular, perineuronal and interstitial guidance cues. Current in vitro assays to probe glioma cell invasion, however, are limited in recapitulating the modes and adaptability of glioma invasion observed in brain parenchyma, including collective behaviours. To mimic in vivo-like glioma cell invasion in vitro, we here applied three tissue-inspired 3D environments combining multicellular glioma spheroids and reconstituted microanatomic features of vascular and interstitial brain structures. Radial migration from multicellular glioma spheroids of human cell lines and patient-derived xenograft cells was monitored using (1) reconstituted basement membrane/hyaluronan interfaces representing the space along brain vessels; (2) 3D scaffolds generated by multi-layered mouse astrocytes to reflect brain interstitium; and (3) freshly isolated mouse brain slice culture ex vivo. The invasion patterns in vitro were validated using histological analysis of brain sections from glioblastoma patients and glioma xenografts infiltrating the mouse brain. Each 3D assay recapitulated distinct aspects of major glioma invasion patterns identified in mouse xenografts and patient brain samples, including individually migrating cells, collective strands extending along blood vessels, and multicellular networks of interconnected glioma cells infiltrating the neuropil. In conjunction, these organotypic assays enable a range of invasion modes used by glioma cells and will be applicable for mechanistic analysis and targeting of glioma cell dissemination.


Asunto(s)
Astrocitos/patología , Vasos Sanguíneos/patología , Neoplasias Encefálicas/patología , Glioma/patología , Esferoides Celulares/patología , Animales , Humanos , Ratones , Células Tumorales Cultivadas
12.
Bioconjug Chem ; 28(2): 539-548, 2017 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-28045502

RESUMEN

Conjugation of llama single domain antibody fragments (Variable Heavy chain domains of Heavy chain antibodies, VHHs) to diagnostic or therapeutic nanoparticles, peptides, proteins, or drugs offers many opportunities for optimized targeted cancer treatment. Currently, mostly nonspecific conjugation strategies or genetic fusions are used that may compromise VHH functionality. In this paper we present a versatile modular approach for bioorthogonal VHH modification and conjugation. First, sortase A mediated transPEGylation is used for introduction of a chemical click moiety. The resulting clickable VHHs are then used for conjugation to other groups employing the Cu+-independent strain-promoted alkyne-azide cycloadition (SPAAC) reaction. Using this approach, tail-to-tail bispecific VHHs and VHH-targeted nanoparticles are generated without affecting VHH functionality. Furthermore, this approach allows the bioconjugation of multiple moieties to VHHs for simple and convenient production of VHH-based theranostics.


Asunto(s)
Camélidos del Nuevo Mundo/inmunología , Inmunoconjugados/química , Cadenas Pesadas de Inmunoglobulina/química , Nanopartículas/química , Polietilenglicoles/química , Anticuerpos de Dominio Único/química , Alquinos/química , Aminoaciltransferasas/metabolismo , Animales , Azidas/química , Proteínas Bacterianas/metabolismo , Química Clic/métodos , Reacción de Cicloadición/métodos , Cisteína Endopeptidasas/metabolismo , Inmunoconjugados/inmunología , Inmunoconjugados/metabolismo , Cadenas Pesadas de Inmunoglobulina/inmunología , Cadenas Pesadas de Inmunoglobulina/metabolismo , Polietilenglicoles/metabolismo , Anticuerpos de Dominio Único/inmunología , Anticuerpos de Dominio Único/metabolismo
13.
Acta Neuropathol ; 133(2): 263-282, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28074274

RESUMEN

In theory, in vitro and in vivo models for human gliomas have great potential to not only enhance our understanding of glioma biology, but also to facilitate the development of novel treatment strategies for these tumors. For reliable prediction and validation of the effects of different therapeutic modalities, however, glioma models need to comply with specific and more strict demands than other models of cancer, and these demands are directly related to the combination of genetic aberrations and the specific brain micro-environment gliomas grow in. This review starts with a brief introduction on the pathological and molecular characteristics of gliomas, followed by an overview of the models that have been used in the last decades in glioma research. Next, we will discuss how these models may play a role in better understanding glioma development and especially in how they can aid in the design and optimization of novel therapies. The strengths and weaknesses of the different models will be discussed in light of genotypic, phenotypic and metabolic characteristics of human gliomas. The last part of this review provides some examples of how therapy experiments using glioma models can lead to deceptive results when such characteristics are not properly taken into account.


Asunto(s)
Neoplasias Encefálicas , Glioma , Modelos Teóricos , Animales , Humanos
14.
Biomacromolecules ; 18(4): 1302-1310, 2017 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-28269985

RESUMEN

Recombinant llama heavy-chain antibody fragments (VHHs) are promising tools in the field of targeted nanomedicine. 7D12, a VHH against the epidermal growth factor receptor (EGFR) that is overexpressed in various cancers, has been evaluated as an effective cancer-targeting VHH in multiple studies. The small size of VHHs (15-20 kDa) results in a low circulation half-life, which can be disadvantageous for certain applications. A solution to this problem is to attach VHHs to the surface of nanoparticles to increase the hydrodynamic radius of the conjugate. This approach simultaneously allows the incorporation of different VHHs and other targeting moieties and therapeutic components into one structure, creating multispecificity and versatility for therapy and diagnosis. Here, we present the construction of highly defined 7D12-containing nanoparticles by utilizing thermoresponsive diblock elastin-like peptides that reversibly self-assemble into micellar structures. The resulting particles have a hydrodynamic radius of 24.3 ± 0.9 nm and retain full EGFR-binding capacity. We present proof of concept of the usability of such particles by controlled incorporation of a photosensitizer and show that the resulting nanoparticles induce EGFR-specific light-induced cell killing. This approach is easily extended to the controlled incorporation of various functional modules, improving therapy and diagnosis with targeted nanomedicine.


Asunto(s)
Elastina/química , Nanopartículas/química , Péptidos/química , Fármacos Fotosensibilizantes/química , Proteínas Recombinantes de Fusión/farmacología , Anticuerpos de Dominio Único/química , Animales , Camélidos del Nuevo Mundo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Estabilidad de Medicamentos , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/genética , Escherichia coli/genética , Humanos , Luz , Nanomedicina , Fotoquimioterapia , Proteínas Recombinantes de Fusión/sangre , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética
15.
Ann Surg Oncol ; 23(9): 2745-52, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27334220

RESUMEN

BACKGROUND: In synovial sarcomas alterations in the cyclin D1-CDK4/6-Rb axis have been described. Also, ß-catenin, a cyclin D1 regulator, is often overexpressed. Additionally, studies have shown that the t(X;18) translocation influences tumor behavior partly through cyclin D1 activation. We investigated how alterations in the cyclin D1-CDK4/6-Rb axis impact prognosis and studied effects of targeting this axis with the CDK4/6 inhibitor palbociclib. METHODS: Synovial sarcoma samples (n = 43) were immunohistochemically stained for ß-catenin, cyclin D1, p16, p21, p27, Rb, and phospho-Rb. Fluorescent in situ hybridization (FISH) was performed to detect CCND1 amplification or translocation. In 4 synovial sarcoma cell lines sensitivity to palbociclib was investigated using cell viability assays, and effects on the sensitive cell lines were evaluated on protein level and by cell cycle arrest. RESULTS: Expression of nuclear phospho-Rb and nuclear ß-catenin in the patient samples was associated with poor survival. FISH showed a sporadic translocation of CCND1 in a subset of tumors. An 8-fold CCND1 amplification was found in 1 cell line, but not in the patient samples investigated. Palbociclib effectively inhibited Rb-phosphorylation in 3 cell lines, resulting in an induction of a G1 arrest and proliferation block. CONCLUSIONS: In this series nuclear phospho-Rb and nuclear ß-catenin expression were negative prognostic factors. In vitro data suggest that palbociclib may be a potential treatment for a subset of synovial sarcoma patients. Whether this effect can be enhanced by combination treatment deserves further preclinical investigations.


Asunto(s)
Antineoplásicos/uso terapéutico , Piperazinas/uso terapéutico , Piridinas/uso terapéutico , Sarcoma Sinovial/tratamiento farmacológico , Sarcoma Sinovial/metabolismo , Adolescente , Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ciclina D1/genética , Quinasa 4 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 6 Dependiente de la Ciclina/antagonistas & inhibidores , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , Femenino , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Humanos , Inmunohistoquímica , Masculino , Fosforilación/efectos de los fármacos , Piperazinas/farmacología , Piridinas/farmacología , Proteína de Retinoblastoma/metabolismo , Sarcoma Sinovial/genética , Tasa de Supervivencia , Adulto Joven , beta Catenina/metabolismo
16.
Biochim Biophys Acta ; 1846(1): 66-74, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24747768

RESUMEN

Diffuse gliomas comprise a group of primary brain tumors that originate from glial (precursor) cells and present as a variety of malignancy grades which have in common that they grow by diffuse infiltration. This phenotype complicates treatment enormously as it precludes curative surgery and radiotherapy. Furthermore, diffusely infiltrating glioma cells often hide behind a functional blood-brain barrier, hampering delivery of systemically administered therapeutic and diagnostic compounds to the tumor cells. The present review addresses the biological mechanisms that underlie the diffuse infiltrative phenotype, knowledge of which may improve treatment strategies for this disastrous tumor type. The invasive phenotype is specific for glioma: most other brain tumor types, both primary and metastatic, grow as delineated lesions. Differences between the genetic make-up of glioma and that of other tumor types may therefore help to unravel molecular pathways, involved in diffuse infiltrative growth. One such difference concerns mutations in the NADP(+)-dependent isocitrate dehydrogenase (IDH1 and IDH2) genes, which occur in >80% of cases of low grade glioma and secondary glioblastoma. In this review we present a novel hypothesis which links IDH1 and IDH2 mutations to glutamate metabolism, possibly explaining the specific biological behavior of diffuse glioma.


Asunto(s)
Neoplasias Encefálicas/patología , Quimiotaxis , Glioma/patología , Ácido Glutámico/fisiología , Animales , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Transformación Celular Neoplásica/genética , Quimiotaxis/efectos de los fármacos , Inhibidores Enzimáticos/uso terapéutico , Glioma/tratamiento farmacológico , Glioma/genética , Ácido Glutámico/farmacología , Glutamina/metabolismo , Humanos , Isocitrato Deshidrogenasa/antagonistas & inhibidores , Isocitrato Deshidrogenasa/genética , Isocitrato Deshidrogenasa/metabolismo
17.
Acta Neuropathol ; 130(1): 131-44, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25862637

RESUMEN

MET has gained interest as a therapeutic target for a number of malignancies because of its involvement in tumorigenesis, invasion and metastasis. At present, a number of inhibitors, both antibodies against MET or its ligand hepatocyte growth factor, and small molecule MET tyrosine kinase inhibitors are in clinical trials. We here describe a novel variant of MET that is expressed in 6% of high-grade gliomas. Characterization of this mutation in a glioma cell line revealed that it consists of an intronic deletion, resulting in a splice event connecting an intact splice donor site in exon 6 with the next splice acceptor site being that of exon 9. The encoded protein lacks parts of the extracellular IPT domains 1 and 2, encoded by exons 7 and 8, resulting in a novel pseudo-IPT and is named MET(Δ7-8). MET(Δ7-8) is located predominantly in the cytosol and is constitutively active. The auto-activating nature of MET(Δ7-8), in combination with a lack of transmembrane localization, renders MET(Δ7-8) not targetable using antibodies, although the protein is efficiently deactivated by MET-specific tyrosine kinase inhibitors. Testing of MET-expressing tumors for the presence of this variant may be important for treatment decision making.


Asunto(s)
Glioma/genética , Proteínas Proto-Oncogénicas c-met/genética , Proteínas Proto-Oncogénicas c-met/metabolismo , Eliminación de Secuencia , Anilidas/farmacología , Animales , Anticuerpos/metabolismo , Carcinoma/genética , Carcinoma/metabolismo , Carcinoma/patología , Línea Celular Tumoral , Femenino , Glioma/tratamiento farmacológico , Glioma/metabolismo , Glioma/patología , Factor de Crecimiento de Hepatocito/metabolismo , Humanos , Masculino , Ratones , Clasificación del Tumor , Trasplante de Neoplasias , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/patología , Conformación Proteica , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Piridinas/farmacología , ARN Mensajero/metabolismo , Sarcoma/genética , Sarcoma/metabolismo , Sarcoma/patología
18.
Methods ; 62(3): 246-54, 2013 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-23769806

RESUMEN

The increasing use of zebrafish larvae for biomedical research applications is resulting in versatile models for a variety of human diseases. These models exploit the optical transparency of zebrafish larvae and the availability of a large genetic tool box. Here we present detailed protocols for the robotic injection of zebrafish embryos at very high accuracy with a speed of up to 2000 embryos per hour. These protocols are benchmarked for several applications: (1) the injection of DNA for obtaining transgenic animals, (2) the injection of antisense morpholinos that can be used for gene knock-down, (3) the injection of microbes for studying infectious disease, and (4) the injection of human cancer cells as a model for tumor progression. We show examples of how the injected embryos can be screened at high-throughput level using fluorescence analysis. Our methods open up new avenues for the use of zebrafish larvae for large compound screens in the search for new medicines.


Asunto(s)
Ensayos Analíticos de Alto Rendimiento/métodos , Larva/genética , Microinyecciones/métodos , Robótica/métodos , Pez Cebra/genética , Animales , Animales Modificados Genéticamente , Benchmarking , Modelos Animales de Enfermedad , Embrión no Mamífero/inmunología , Embrión no Mamífero/microbiología , Embrión no Mamífero/ultraestructura , Técnicas de Silenciamiento del Gen , Ensayos Analíticos de Alto Rendimiento/instrumentación , Humanos , Larva/inmunología , Larva/microbiología , Larva/ultraestructura , Microscopía Fluorescente , Morfolinos/administración & dosificación , Mycobacterium tuberculosis/inmunología , Trasplante de Neoplasias , Oligonucleótidos Antisentido/administración & dosificación , Staphylococcus epidermidis/inmunología , Células Tumorales Cultivadas/trasplante , Pez Cebra/inmunología , Pez Cebra/microbiología
19.
Int J Cancer ; 133(2): 427-36, 2013 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-23335077

RESUMEN

Because novel therapeutic options are limited in Ewing sarcomas (ES), we investigated the expression, genetic aberrations and clinical relevance of MET and anaplastic lymphoma kinase (ALK) in ES and determined the relevance of targeting these receptors. MET and ALK protein expression was determined immunohistochemically in 31 (50 samples) and 36 (59 samples) ES patients, respectively. Samples included primary tumors, postchemotherapy resections, metastases and relapses. MET and ALK RTK domains were sequenced in respectively 33 and 32 tumors. Five ES cell lines were treated in vitro with the MET/ALK-inhibitor crizotinib, the ALK-inhibitor NVP-TAE684 or the MET-inhibitor cabozantinib and analyzed by MTT assays. Modest to high MET and ALK expression was detected in the majority of ES (86 and 69%, respectively). ALK expression was significantly lower in postchemotherapy resections compared to paired untreated primary tumors (p = 0.031, z = -2.310, n = 11). In primary tumors (n = 20), membranous MET expression significantly correlated with a poor overall survival (OS) (60 vs. 197 months, p = 0.014). There was a trend toward a poor event-free survival (67 vs. 111 months, p = 0.078) and OS (88 vs. 128 months, p = 0.074) in patients with highest ALK levels (n = 29). ALK or MET RTK domain aberrations were demonstrated in 5/32 (16%) and 3/33 (9%) tumors, respectively. Crizotinib (IC50 1.22-3.59 µmol/L), NVP-TAE684 (IC50 0.15-0.79 µmol/L) and cabozantinib (IC50 2.69-8.27 µmol/L) affected ES cell viability in vitro. Altogether, our data suggest that MET and ALK are potential novel therapeutic targets in ES and targeting these receptors may be of great interest to rationally design future studies in ES.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Proteínas Proto-Oncogénicas c-met/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Sarcoma de Ewing/metabolismo , Adolescente , Adulto , Quinasa de Linfoma Anaplásico , Anilidas/farmacología , Niño , Preescolar , Aberraciones Cromosómicas , Crizotinib , Femenino , Perfilación de la Expresión Génica , Humanos , Inmunohistoquímica , Concentración 50 Inhibidora , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Pirazoles/farmacología , Piridinas/farmacología , Pirimidinas/farmacología , Recurrencia , Sales de Tetrazolio/farmacología , Tiazoles/farmacología , Resultado del Tratamiento , Adulto Joven
20.
Comput Struct Biotechnol J ; 21: 4424-4431, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37731597

RESUMEN

The cervicovaginal microbiome (CVM) is a dynamic continuous microenvironment that can be clustered in microbial community state types (CSTs) and is associated with women's cervical health. Lactobacillus-depleted communities particularly associate with an increased susceptibility for persistence of high-risk human papillomavirus (hrHPV) infections and progression of disease, but the long-term ecological dynamics of CSTs after hrHPV infection diagnosis remain poorly understood. To determine such dynamics, we examined the CVM of our longitudinal cohort of 141 women diagnosed with hrHPV infection at baseline with collected cervical smears at two timepoints six-months apart. Here we describe that the long-term microbiome dissimilarity has a positive correlation with microbial diversity at both visits and that women with high abundance and dominance for Lactobacillus iners at baseline exhibit more similar microbiome composition at second visit than women with Lactobacillus-depleted communities at baseline. We further show that the species Lactobacillus acidophilus and Megasphaera genomosp type 1 associate with CST changes between both visits. Lastly, we also observe that Gardnerella vaginalis is associated with the stability of Lactobacillus-depleted communities while L. iners is associated with the instability of Megasphaera genomosp type 1-dominated communities. Our data suggest dynamic patterns of cervicovaginal CSTs during hrHPV infection, which could be potentially used to develop microbiome-based therapies against infection progression towards disease.

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