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1.
EMBO Rep ; 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38937629

RESUMEN

The EMT-transcription factor ZEB1 is heterogeneously expressed in tumor cells and in cancer-associated fibroblasts (CAFs) in colorectal cancer (CRC). While ZEB1 in tumor cells regulates metastasis and therapy resistance, its role in CAFs is largely unknown. Combining fibroblast-specific Zeb1 deletion with immunocompetent mouse models of CRC, we observe that inflammation-driven tumorigenesis is accelerated, whereas invasion and metastasis in sporadic cancers are reduced. Single-cell transcriptomics, histological characterization, and in vitro modeling reveal a crucial role of ZEB1 in CAF polarization, promoting myofibroblastic features by restricting inflammatory activation. Zeb1 deficiency impairs collagen deposition and CAF barrier function but increases NFκB-mediated cytokine production, jointly promoting lymphocyte recruitment and immune checkpoint activation. Strikingly, the Zeb1-deficient CAF repertoire sensitizes to immune checkpoint inhibition, offering a therapeutic opportunity of targeting ZEB1 in CAFs and its usage as a prognostic biomarker. Collectively, we demonstrate that ZEB1-dependent plasticity of CAFs suppresses anti-tumor immunity and promotes metastasis.

2.
Nat Commun ; 15(1): 4096, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750019

RESUMEN

The presence of heterogeneity in responses to oncolytic virotherapy poses a barrier to clinical effectiveness, as resistance to this treatment can occur through the inhibition of viral spread within the tumor, potentially leading to treatment failures. Here we show that 4-octyl itaconate (4-OI), a chemical derivative of the Krebs cycle-derived metabolite itaconate, enhances oncolytic virotherapy with VSVΔ51 in various models including human and murine resistant cancer cell lines, three-dimensional (3D) patient-derived colon tumoroids and organotypic brain tumor slices. Furthermore, 4-OI in combination with VSVΔ51 improves therapeutic outcomes in a resistant murine colon tumor model. Mechanistically, we find that 4-OI suppresses antiviral immunity in cancer cells through the modification of cysteine residues in MAVS and IKKß independently of the NRF2/KEAP1 axis. We propose that the combination of a metabolite-derived drug with an oncolytic virus agent can greatly improve anticancer therapeutic outcomes by direct interference with the type I IFN and NF-κB-mediated antiviral responses.


Asunto(s)
Viroterapia Oncolítica , Virus Oncolíticos , Succinatos , Animales , Humanos , Viroterapia Oncolítica/métodos , Succinatos/farmacología , Ratones , Línea Celular Tumoral , Interferón Tipo I/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Neoplasias del Colon/terapia , Neoplasias del Colon/inmunología , Neoplasias del Colon/tratamiento farmacológico , Antivirales/farmacología , FN-kappa B/metabolismo , Quinasa I-kappa B/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Inflamación/tratamiento farmacológico , Femenino , Virus de la Estomatitis Vesicular Indiana/fisiología , Virus de la Estomatitis Vesicular Indiana/efectos de los fármacos , Transducción de Señal/efectos de los fármacos
4.
iScience ; 26(12): 108399, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38047086

RESUMEN

Precision oncology approaches for patients with colorectal cancer (CRC) continue to lag behind other solid cancers. Functional precision oncology-a strategy that is based on perturbing primary tumor cells from cancer patients-could provide a road forward to personalize treatment. We extend this paradigm to measuring proteome activity landscapes by acquiring quantitative phosphoproteomic data from patient-derived organoids (PDOs). We show that kinase inhibitors induce inhibitor- and patient-specific off-target effects and pathway crosstalk. Reconstruction of the kinase networks revealed that the signaling rewiring is modestly affected by mutations. We show non-genetic heterogeneity of the PDOs and upregulation of stemness and differentiation genes by kinase inhibitors. Using imaging mass-cytometry-based profiling of the primary tumors, we characterize the tumor microenvironment (TME) and determine spatial heterocellular crosstalk and tumor-immune cell interactions. Collectively, we provide a framework for inferring tumor cell intrinsic signaling and external signaling from the TME to inform precision (immuno-) oncology in CRC.

5.
Cancer Discov ; 13(10): 2192-2211, 2023 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-37489084

RESUMEN

In colorectal cancers, the tumor microenvironment plays a key role in prognosis and therapy efficacy. Patient-derived tumor organoids (PDTO) show enormous potential for preclinical testing; however, cultured tumor cells lose important characteristics, including the consensus molecular subtypes (CMS). To better reflect the cellular heterogeneity, we established the colorectal cancer organoid-stroma biobank of matched PDTOs and cancer-associated fibroblasts (CAF) from 30 patients. Context-specific phenotyping showed that xenotransplantation or coculture with CAFs improves the transcriptomic fidelity and instructs subtype-specific stromal gene expression. Furthermore, functional profiling in coculture exposed CMS4-specific therapeutic resistance to gefitinib and SN-38 and prognostic expression signatures. Chemogenomic library screening identified patient- and therapy-dependent mechanisms of stromal resistance including MET as a common target. Our results demonstrate that colorectal cancer phenotypes are encrypted in the cancer epithelium in a plastic fashion that strongly depends on the context. Consequently, CAFs are essential for a faithful representation of molecular subtypes and therapy responses ex vivo. SIGNIFICANCE: Systematic characterization of the organoid-stroma biobank provides a resource for context dependency in colorectal cancer. We demonstrate a colorectal cancer subtype memory of PDTOs that is independent of specific driver mutations. Our data underscore the importance of functional profiling in cocultures for improved preclinical testing and identification of stromal resistance mechanisms. This article is featured in Selected Articles from This Issue, p. 2109.


Asunto(s)
Fibroblastos Asociados al Cáncer , Neoplasias Colorrectales , Humanos , Bancos de Muestras Biológicas , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Células Tumorales Cultivadas , Fibroblastos Asociados al Cáncer/metabolismo , Organoides/patología , Microambiente Tumoral/genética
6.
J Allergy Clin Immunol ; 152(4): 949-960, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37390900

RESUMEN

BACKGROUND: The actin cytoskeleton has a crucial role in the maintenance of the immune homeostasis by controlling various cellular processes, including cell migration. Mutations in TTC7A have been described as the cause of a primary immunodeficiency associated to different degrees of gut involvement and alterations in the actin cytoskeleton dynamics. OBJECTIVES: This study investigates the impact of TTC7A deficiency in immune homeostasis. In particular, the role of the TTC7A/phosphatidylinositol 4 kinase type III α pathway in the control of leukocyte migration and actin dynamics. METHODS: Microfabricated devices were leveraged to study cell migration and actin dynamics of murine and patient-derived leukocytes under confinement at the single-cell level. RESULTS: We show that TTC7A-deficient lymphocytes exhibit an altered cell migration and reduced capacity to deform through narrow gaps. Mechanistically, TTC7A-deficient phenotype resulted from impaired phosphoinositide signaling, leading to the downregulation of the phosphoinositide 3-kinase/AKT/RHOA regulatory axis and imbalanced actin cytoskeleton dynamics. TTC7A-associated phenotype resulted in impaired cell motility, accumulation of DNA damage, and increased cell death in dense 3-dimensional gels in the presence of chemokines. CONCLUSIONS: These results highlight a novel role of TTC7A as a critical regulator of lymphocyte migration. Impairment of this cellular function is likely to contribute to the pathophysiology underlying progressive immunodeficiency in patients.


Asunto(s)
Actinas , Fosfatidilinositol 3-Quinasas , Humanos , Animales , Ratones , Muerte Celular , Mutación , Movimiento Celular/genética , Daño del ADN , Proteínas , 1-Fosfatidilinositol 4-Quinasa
7.
Sci Adv ; 9(11): eadd8564, 2023 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-36921054

RESUMEN

Immune checkpoint inhibitors (ICIs) enhance anticancer immunity by releasing repressive signals into tumor microenvironments (TMEs). To be effective, ICIs require preexisting immunologically "hot" niches for tumor antigen presentation and lymphocyte recruitment. How the mutational landscape of cancer cells shapes these immunological niches remains poorly defined. We found in human and murine colorectal cancer (CRC) models that the superior antitumor immune response of mismatch repair (MMR)-deficient CRC required tumor cell-intrinsic activation of cGAS-STING signaling triggered by genomic instability. Subsequently, we synthetically enforced STING signaling in CRC cells with intact MMR signaling using constitutively active STING variants. Even in MMR-proficient CRC, genetically encoded gain-of-function STING was sufficient to induce cancer cell-intrinsic interferon signaling, local activation of antigen-presenting cells, recruitment of effector lymphocytes, and sensitization of previously "cold" TMEs to ICI therapy in vivo. Thus, our results introduce a rational strategy for modulating cancer cell-intrinsic programs via engineered STING enforcement to sensitize resistant tumors to ICI responsiveness.


Asunto(s)
Neoplasias del Colon , Transducción de Señal , Humanos , Animales , Ratones , Presentación de Antígeno , Células Presentadoras de Antígenos , Inestabilidad Genómica , Microambiente Tumoral
8.
Mol Oncol ; 17(8): 1545-1566, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36861295

RESUMEN

Control of tumour development and growth by the immune system critically defines patient fate and survival. What regulates the escape of colorectal tumours from destruction by the immune system remains currently unclear. Here, we investigated the role of intestinal synthesis of glucocorticoids in the tumour development during an inflammation-induced mouse model of colorectal cancer. We demonstrate that the local synthesis of immunoregulatory glucocorticoids has dual roles in the regulation of intestinal inflammation and tumour development. In the inflammation phase, LRH-1/Nr5A2-regulated and Cyp11b1-mediated intestinal glucocorticoid synthesis prevents tumour development and growth. In established tumours, however, tumour-autonomous Cyp11b1-mediated glucocorticoid synthesis suppresses anti-tumour immune responses and promotes immune escape. Transplantation of glucocorticoid synthesis-proficient colorectal tumour organoids into immunocompetent recipient mice resulted in rapid tumour growth, whereas transplantation of Cyp11b1-deleted and glucocorticoid synthesis-deficient tumour organoids was characterized by reduced tumour growth and increased immune cell infiltration. In human colorectal tumours, high expression of steroidogenic enzymes correlated with the expression of other immune checkpoints and suppressive cytokines, and negatively correlated with overall patients' survival. Thus, LRH-1-regulated tumour-specific glucocorticoid synthesis contributes to tumour immune escape and represents a novel potential therapeutic target.


Asunto(s)
Neoplasias Colorrectales , Glucocorticoides , Humanos , Ratones , Animales , Glucocorticoides/farmacología , Esteroide 11-beta-Hidroxilasa/metabolismo , Intestinos , Inflamación , Neoplasias Colorrectales/genética
9.
ACS Chem Biol ; 18(4): 822-836, 2023 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-36944371

RESUMEN

Well-characterized small molecules are essential tools for studying the biology and therapeutic relevance of a target protein. However, many compounds reported in the literature and routinely studied in biomedical research lack the potency and selectivity required for mechanistic cellular studies on the function of a given protein. Furthermore, commercially available compounds often do not include useful tools developed by industry as part of their research and development efforts, as they frequently remain proprietary. The freely available donated chemical probe (DCP) library, fueled by generous donations of compounds from industry and academia, enables easy access to a steadily growing collection of these valuable and well-characterized tools. Here, we provide a systematic description of the current DCP library collection and their associated comprehensive characterization data, including a variety of in vitro and cellular assays. Of note, we characterized the set in relevant human primary models by employing hepatotoxicity screening in primary human liver spheroids and viability screening in patient-derived colorectal cancer organoids and matched normal-adjacent epithelium. Taken together, the DCP library represents a well-annotated, openly available collection of tool compounds for studying a wide range of targets, including kinases, G-protein-coupled receptors, and ion channels. As such, it represents a unique resource for the biomedical research community.


Asunto(s)
Sondas Moleculares , Neoplasias , Bibliotecas de Moléculas Pequeñas , Humanos , Hígado , Sistemas Microfisiológicos , Neoplasias/metabolismo , Organoides/metabolismo , Organoides/patología , Proteínas/metabolismo , Bibliotecas de Moléculas Pequeñas/clasificación , Sondas Moleculares/química , Sondas Moleculares/farmacología
10.
Gastroenterology ; 164(2): 214-227, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36402192

RESUMEN

BACKGROUND & AIMS: Epigenetic processes regulating gene expression contribute markedly to epithelial cell plasticity in colorectal carcinogenesis. The lysine methyltransferase SUV420H2 comprises an important regulator of epithelial plasticity and is primarily responsible for trimethylation of H4K20 (H4K20me3). Loss of H4K20me3 has been suggested as a hallmark of human cancer due to its interaction with DNMT1. However, the role of Suv4-20h2 in colorectal cancer is unknown. METHODS: We examined the alterations in histone modifications in patient-derived colorectal cancer organoids. Patient-derived colorectal cancer organoids and mouse intestinal organoids were genetically manipulated for functional studies in patient-derived xenograft and orthotopic transplantation. Gene expression profiling, micrococcal nuclease assay, and chromatin immunoprecipitation were performed to understand epigenetic regulation of chromatin states and gene expression in patient-derived and mouse intestinal organoids. RESULTS: We found that reduced H4K20me3 levels occurred predominantly in right-sided patient-derived colorectal cancer organoids, which were associated with increased chromatin accessibility. Re-compaction of chromatin by methylstat, a histone demethylase inhibitor, resulted in reduced growth selectively in subcutaneously grown tumors derived from right-sided cancers. Using mouse intestinal organoids, we confirmed that Suv4-20h2-mediated H4K20me3 is required for maintaining heterochromatin compaction and to prevent R-loop formation. Cross-species comparison of Suv4-20h2-depleted murine organoids with right-sided colorectal cancer organoids revealed a large overlap of gene signatures involved in chromatin silencing, DNA methylation, and stemness/Wnt signaling. CONCLUSIONS: Loss of Suv4-20h2-mediated H4K20me3 drives right-sided colorectal tumorigenesis through an epigenetically controlled mechanism of chromatin compaction. Our findings unravel a conceptually novel approach for subtype-specific therapy of this aggressive form of colorectal cancer.


Asunto(s)
Neoplasias del Colon , N-Metiltransferasa de Histona-Lisina , Animales , Humanos , Ratones , Transformación Celular Neoplásica/genética , Cromatina/genética , Neoplasias del Colon/genética , Neoplasias Colorrectales/genética , Epigénesis Genética , Histonas/metabolismo , Xenoinjertos , N-Metiltransferasa de Histona-Lisina/metabolismo
11.
Immunity ; 55(11): 2059-2073.e8, 2022 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-36351375

RESUMEN

T memory stem cells (TSCM) display increased self-renewal and prolonged survival capabilities, thus preventing T cell exhaustion and promoting effective anti-tumor T cell responses. TSCM cells can be expanded by Urolithin A (UA), which is produced by the commensal gut microbiome from foods rich in ellagitannins and is known to improve mitochondrial health. Oral UA administration to tumor-bearing mice conferred strong anti-tumor CD8+ T cell immunity, whereas ex vivo UA pre-treated T cells displayed improved anti-tumor function upon adoptive cell transfer. UA-induced TSCM formation depended on Pink1-mediated mitophagy triggering cytosolic release of the mitochondrial phosphatase Pgam5. Cytosolic Pgam5 dephosphorylated ß-catenin, which drove Wnt signaling and compensatory mitochondrial biogenesis. Collectively, we unravel a critical signaling pathway linking mitophagy to TSCM formation and suggest that the well-tolerated metabolic compound UA represents an attractive option to improve immune therapy.


Asunto(s)
Cumarinas , Mitofagia , Ratones , Animales , Cumarinas/farmacología , Vía de Señalización Wnt , Células Madre , Memoria Inmunológica
12.
Exp Mol Med ; 53(10): 1483-1494, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34663937

RESUMEN

Organoid technology allows the expansion of primary epithelial cells from normal and diseased tissues, providing a unique model for human (patho)biology. In a three-dimensional environment, adult stem cells self-organize and differentiate to gain tissue-specific features. Accessibility to genetic manipulation enables the investigation of the molecular mechanisms underlying cell fate regulation, cell differentiation and cell interactions. In recent years, powerful methodologies using lentiviral transgenesis, CRISPR/Cas9 gene editing, and single-cell readouts have been developed to study gene function and carry out genetic screens in organoids. However, the multicellularity and dynamic nature of stem cell-derived organoids also present challenges for genetic experimentation. In this review, we focus on adult gastrointestinal organoids and summarize the state-of-the-art protocols for successful transgenesis. We provide an outlook on emerging genetic techniques that could further increase the applicability of organoids and enhance the potential of organoid-based techniques to deepen our understanding of gene function in tissue biology.


Asunto(s)
Células Madre Adultas , Organoides , Diferenciación Celular/genética , Edición Génica/métodos , Técnicas de Transferencia de Gen , Humanos
13.
Cancer Res ; 80(24): 5569-5582, 2020 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-33055221

RESUMEN

Tumor progression is recognized as a result of an evolving cross-talk between tumor cells and their surrounding nontransformed stroma. Although Wnt signaling has been intensively studied in colorectal cancer, it remains unclear whether activity in the tumor-associated stroma contributes to malignancy. To specifically interfere with stromal signals, we generated Wnt-independent tumor organoids that secrete the Wnt antagonist Sfrp1. Subcutaneous transplantation into immunocompetent as well as immunodeficient mice resulted in a strong reduction of tumor growth. Histologic and transcriptomic analyses revealed that Sfrp1 induced an epithelial-mesenchymal transition (EMT) phenotype in tumor cells without affecting tumor-intrinsic Wnt signaling, suggesting involvement of nonimmune stromal cells. Blockage of canonical signaling using Sfrp1, Dkk1, or fibroblast-specific genetic ablation of ß-catenin strongly decreased the number of cancer-associated myofibroblasts (myCAF). Wnt activity in CAFs was linked with distinct subtypes, where low and high levels induced an inflammatory-like CAF (iCAF) subtype or contractile myCAFs, respectively. Coculture of tumor organoids with iCAFs resulted in significant upregulation of EMT markers, while myCAFs reverted this phenotype. In summary, we show that tumor growth and malignancy are differentially regulated via distinct fibroblast subtypes under the influence of juxtacrine Wnt signals. SIGNIFICANCE: This study provides evidence for Wnt-induced functional diversity of colorectal cancer-associated fibroblasts, representing a non-cell autonomous mechanism for colon cancer progression. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/24/5569/F1.large.jpg.


Asunto(s)
Fibroblastos Asociados al Cáncer/metabolismo , Neoplasias Colorrectales/metabolismo , Progresión de la Enfermedad , Transición Epitelial-Mesenquimal/genética , Fenotipo , Vía de Señalización Wnt/genética , Proteína Wnt3/metabolismo , Animales , Supervivencia Celular/genética , Técnicas de Cocultivo , Neoplasias Colorrectales/patología , Medios de Cultivo Condicionados , Humanos , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones SCID , Ratones Transgénicos , Organoides/metabolismo , Organoides/trasplante , Transducción Genética , Proteína Wnt3/genética
14.
J Exp Med ; 217(10)2020 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-32749453

RESUMEN

Recently, a transcriptome-based consensus molecular subtype (CMS) classification of colorectal cancer (CRC) has been established, which may ultimately help to individualize CRC therapy. However, the lack of animal models that faithfully recapitulate the different molecular subtypes impedes adequate preclinical testing of stratified therapeutic concepts. Here, we demonstrate that constitutive AKT activation in intestinal epithelial cells markedly enhances tumor invasion and metastasis in Trp53ΔIEC mice (Trp53ΔIECAktE17K) upon challenge with the carcinogen azoxymethane. Gene-expression profiling indicates that Trp53ΔIECAktE17K tumors resemble the human mesenchymal colorectal cancer subtype (CMS4), which is characterized by the poorest survival rate among the four CMSs. Trp53ΔIECAktE17K tumor cells are characterized by Notch3 up-regulation, and treatment of Trp53ΔIECAktE17K mice with a NOTCH3-inhibiting antibody reduces invasion and metastasis. In CRC patients, NOTCH3 expression correlates positively with tumor grading and the presence of lymph node as well as distant metastases and is specifically up-regulated in CMS4 tumors. Therefore, we suggest NOTCH3 as a putative target for advanced CMS4 CRC patients.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptor Notch3/metabolismo , Animales , Neoplasias Colorrectales/patología , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Ratones Endogámicos C57BL , Trasplante de Neoplasias , Transducción de Señal , Transcriptoma , Regulación hacia Arriba
15.
Cell Stem Cell ; 26(5): 782-792.e7, 2020 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-32348727

RESUMEN

Colorectal cancer (CRC) is characterized by prominent genetic and phenotypic heterogeneity between patients. To facilitate high-throughput genetic testing and functional identification of tumor drivers, we developed a platform for pooled CRISPR-Cas9 screening in human colon organoids. Using transforming growth factor ß (TGF-ß) resistance as a paradigm to establish sensitivity and scalability in vitro, we identified optimal conditions and strict guide RNA (gRNA) requirements for screening in 3D organoids. We then screened a pan-cancer tumor suppressor gene (TSG) library in pre-malignant organoids with APC-/-;KRASG12D mutations, which were xenografted to study clonal advantages in context of a complex tumor microenvironment. We identified TGFBR2 as the most prevalent TSG, followed by known and previously uncharacterized mediators of CRC growth. gRNAs were validated in a secondary screen using unique molecular identifiers (UMIs) to adjust for clonal drift and to distinguish clone size and abundance. Together, these findings highlight a powerful organoid-based platform for pooled CRISPR-Cas9 screening for patient-specific functional genomics.


Asunto(s)
Sistemas CRISPR-Cas , Organoides , Sistemas CRISPR-Cas/genética , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Colon , Genes Supresores de Tumor , Humanos
16.
J Biol Chem ; 295(14): 4526-4540, 2020 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-32086379

RESUMEN

The small GTPases H, K, and NRAS are molecular switches indispensable for proper regulation of cellular proliferation and growth. Several mutations in the genes encoding members of this protein family are associated with cancer and result in aberrant activation of signaling processes caused by a deregulated recruitment of downstream effector proteins. In this study, we engineered variants of the Ras-binding domain (RBD) of the C-Raf proto-oncogene, Ser/Thr kinase (CRAF). These variants bound with high affinity with the effector-binding site of Ras in an active conformation. Structural characterization disclosed how the newly identified RBD mutations cooperate and thereby enhance affinity with the effector-binding site in Ras compared with WT RBD. The engineered RBD variants closely mimicked the interaction mode of naturally occurring Ras effectors and acted as dominant-negative affinity reagents that block Ras signal transduction. Experiments with cancer cells showed that expression of these RBD variants inhibits Ras signaling, reducing cell growth and inducing apoptosis. Using these optimized RBD variants, we stratified patient-derived colorectal cancer organoids with known Ras mutational status according to their response to Ras inhibition. These results revealed that the presence of Ras mutations was insufficient to predict sensitivity to Ras inhibition, suggesting that not all of these tumors required Ras signaling for proliferation. In summary, by engineering the Ras/Raf interface of the CRAF-RBD, we identified potent and selective inhibitors of Ras in its active conformation that outcompete binding of Ras-signaling effectors.


Asunto(s)
Proteínas Proto-Oncogénicas c-raf/metabolismo , Proteínas ras/metabolismo , Apoptosis , Sitios de Unión , Línea Celular Tumoral , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Humanos , Simulación de Dinámica Molecular , Mutagénesis , Fosfatidilinositol 3-Quinasas/metabolismo , Unión Proteica , Dominios Proteicos , Estructura Terciaria de Proteína , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas c-raf/química , Proteínas Proto-Oncogénicas c-raf/genética , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Transducción de Señal , Proteínas ras/antagonistas & inhibidores , Proteínas ras/genética
17.
Gut ; 69(7): 1269-1282, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31685519

RESUMEN

OBJECTIVE: Cancer-associated fibroblasts (CAFs) influence the tumour microenvironment and tumour growth. However, the role of CAFs in colorectal cancer (CRC) development is incompletely understood. DESIGN: We quantified phosphorylation of STAT3 (pSTAT3) expression in CAFs of human colon cancer tissue using a tissue microarray (TMA) of 375 patients, immunofluorescence staining and digital pathology. To investigate the functional role of CAFs in CRC, we took advantage of two murine models of colorectal neoplasia and advanced imaging technologies. In loss-of-function and gain-of-function experiments, using genetically modified mice with collagen type VI (COLVI)-specific signal transducer and activator of transcription 3 (STAT3) targeting, we evaluated STAT3 signalling in fibroblasts during colorectal tumour development. We performed a comparative gene expression profiling by whole genome RNA-sequencing of fibroblast subpopulations (COLVI+ vs COLVI-) on STAT3 activation (IL-6 vs IL-11). RESULTS: The analysis of pSTAT3 expression in CAFs of human TMAs revealed a negative correlation of increased stromal pSTAT3 expression with the survival of colon cancer patients. In the loss-of-function and gain-of-function approach, we found a critical role of STAT3 activation in fibroblasts in driving colorectal tumourigenesis in vivo. With different imaging technologies, we detected an expansion of activated fibroblasts in colorectal neoplasias. Comparative gene expression profiling of fibroblast subpopulations on STAT3 activation revealed the regulation of transcriptional patterns associated with angiogenesis. Finally, the blockade of proangiogenic signalling significantly reduced colorectal tumour growth in mice with constitutive STAT3 activation in COLVI+ fibroblasts. CONCLUSION: Altogether our work demonstrates a critical role of STAT3 activation in CAFs in CRC development.


Asunto(s)
Neoplasias Colorrectales/etiología , Interleucina-11/metabolismo , Interleucina-6/metabolismo , Factor de Transcripción STAT3/metabolismo , Animales , Colon/metabolismo , Neoplasias Colorrectales/diagnóstico , Fibroblastos/metabolismo , Humanos , Ratones , Fosforilación , Pronóstico , Análisis de Matrices Tisulares , Transcriptoma
18.
EMBO J ; 38(12)2019 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-31036555

RESUMEN

Immunotherapy using chimeric antigen receptor (CAR)-engineered lymphocytes has shown impressive results in leukemia. However, for solid tumors such as colorectal cancer (CRC), new preclinical models are needed that allow to test CAR-mediated cytotoxicity in a tissue-like environment. Here, we developed a platform to study CAR cell cytotoxicity against 3-dimensional (3D) patient-derived colon organoids. Luciferase-based measurement served as a quantitative read-out for target cell viability. Additionally, we set up a confocal live imaging protocol to monitor effector cell recruitment and cytolytic activity at a single organoid level. As proof of principle, we demonstrated efficient targeting in diverse organoid models using CAR-engineered NK-92 cells directed toward a ubiquitous epithelial antigen (EPCAM). Tumor antigen-specific cytotoxicity was studied with CAR-NK-92 cells targeting organoids expressing EGFRvIII, a neoantigen found in several cancers. Finally, we tested a novel CAR strategy targeting FRIZZLED receptors that show increased expression in a subgroup of CRC tumors. Here, comparative killing assays with normal organoids failed to show tumor-specific activity. Taken together, we report a sensitive in vitro platform to evaluate CAR efficacy and tumor specificity in a personalized manner.


Asunto(s)
Neoplasias Colorrectales/patología , Neoplasias Colorrectales/terapia , Citotoxicidad Inmunológica , Modelos Biológicos , Organoides/patología , Receptores Quiméricos de Antígenos/uso terapéutico , Técnicas de Cultivo de Tejidos/métodos , Células Cultivadas , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/inmunología , Citotoxicidad Inmunológica/efectos de los fármacos , Citotoxicidad Inmunológica/genética , Terapia Genética/métodos , Células HEK293 , Humanos , Inmunoterapia Adoptiva/métodos , Cultivo Primario de Células/métodos , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/metabolismo , Receptores de Antígenos de Linfocitos T/uso terapéutico , Receptores Quiméricos de Antígenos/genética , Receptores Quiméricos de Antígenos/metabolismo , Andamios del Tejido/química
19.
Oncogene ; 38(24): 4788-4803, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30816345

RESUMEN

A role of sphingolipids for inflammatory bowel disease and cancer is evident. However, the relative and separate contribution of sphingolipid deterioration in inflammation versus carcinogenesis for the pathophysiology of colitis-associated colon cancer (CAC) was unknown and therefore examined in this study. We performed isogenic bone marrow transplantation of inducible sphingosine-1-phosphate (S1P) lyase knockout mice to specifically modulate sphingolipids and associated genes and proteins in a compartment-specific way in a DSS/AOM mediated CAC model. 3D organoid cultures were used in vitro. S1P lyase (SGPL1) knockout in either immune cells or tissue, caused local sphingolipid accumulation leading to a dichotomic development of CAC: Immune cell SGPL1 knockout (I-SGPL-/-) augmented massive immune cell infiltration initiating colitis with lesions and calprotectin increase. Pathological crypt remodeling plus extracellular S1P-signaling caused delayed tumor formation characterized by S1P receptor 1, STAT3 mRNA increase, as well as programmed cell death ligand 1 expression, accompanied by a putatively counter regulatory STAT1S727 phosphorylation. In contrast, tissue SGPL1 knockout (T-SGPL-/-) provoked immediate occurrence of epithelial-driven tumors with upregulated sphingosine kinase 1, S1P receptor 2 and epidermal growth factor receptor. Here, progressing carcinogenesis was accompanied by an IL-12 to IL-23 shift with a consecutive development of a Th2/GATA3-driven, tumor-favoring microenvironment. Moreover, the knockout models showed distinct lymphopenia and neutrophilia, different from the full SGPL1 knockout. This study shows that depending on the initiating cellular S1P source, the pathophysiology of inflammation-induced cancer versus cancer-induced inflammation develops through separate, discernible molecular steps.


Asunto(s)
Aldehído-Liasas/fisiología , Carcinogénesis , Colitis/etiología , Neoplasias del Colon/complicaciones , Inflamación/etiología , Aldehído-Liasas/genética , Animales , Carcinogénesis/genética , Carcinogénesis/metabolismo , Carcinogénesis/patología , Células Cultivadas , Colitis/genética , Colitis/patología , Colon/metabolismo , Colon/patología , Neoplasias del Colon/genética , Neoplasias del Colon/patología , Femenino , Inflamación/genética , Lisofosfolípidos/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Transducción de Señal/fisiología , Esfingosina/análogos & derivados , Esfingosina/fisiología , Microambiente Tumoral/fisiología
20.
J Exp Med ; 216(3): 704-720, 2019 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-30792186

RESUMEN

Constitutive Wnt activation upon loss of Adenoma polyposis coli (APC) acts as main driver of colorectal cancer (CRC). Targeting Wnt signaling has proven difficult because the pathway is crucial for homeostasis and stem cell renewal. To distinguish oncogenic from physiological Wnt activity, we have performed transcriptome and proteome profiling in isogenic human colon organoids. Culture in the presence or absence of exogenous ligand allowed us to discriminate receptor-mediated signaling from the effects of CRISPR/Cas9-induced APC loss. We could catalog two nonoverlapping molecular signatures that were stable at distinct levels of stimulation. Newly identified markers for normal stem/progenitor cells and adenomas were validated by immunohistochemistry and flow cytometry. We found that oncogenic Wnt signals are associated with good prognosis in tumors of the consensus molecular subtype 2 (CMS2). In contrast, receptor-mediated signaling was linked to CMS4 tumors and poor prognosis. Together, our data represent a valuable resource for biomarkers that allow more precise stratification of Wnt responses in CRC.


Asunto(s)
Colon/patología , Colon/fisiología , Neoplasias del Colon/mortalidad , Organoides/fisiología , Vía de Señalización Wnt/fisiología , Adenoma/genética , Adenoma/metabolismo , Proteína de la Poliposis Adenomatosa del Colon/genética , Proteína de la Poliposis Adenomatosa del Colon/metabolismo , Biomarcadores de Tumor/metabolismo , Neoplasias del Colon/genética , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Regulación de la Expresión Génica , Técnicas de Inactivación de Genes , Humanos , Estimación de Kaplan-Meier , Organoides/patología , Vía de Señalización Wnt/genética
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