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1.
Nat Immunol ; 19(8): 828-837, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29988089

RESUMO

Memory T cells are critical for the immune response to recurring infections. Their instantaneous reactivity to pathogens is empowered by the persistent expression of cytokine-encoding mRNAs. How the translation of proteins from pre-formed cytokine-encoding mRNAs is prevented in the absence of infection has remained unclear. Here we found that protein production in memory T cells was blocked via a 3' untranslated region (3' UTR)-mediated process. Germline deletion of AU-rich elements (AREs) in the Ifng-3' UTR led to chronic cytokine production in memory T cells. This aberrant protein production did not result from increased expression and/or half-life of the mRNA. Instead, AREs blocked the recruitment of cytokine-encoding mRNA to ribosomes; this block depended on the ARE-binding protein ZFP36L2. Thus, AREs mediate repression of translation in mouse and human memory T cells by preventing undesirable protein production from pre-formed cytokine-encoding mRNAs in the absence of infection.


Assuntos
Regiões 3' não Traduzidas/genética , Elementos Ricos em Adenilato e Uridilato/genética , Interferon gama/genética , RNA Mensageiro/genética , Linfócitos T/imunologia , Animais , Células Cultivadas , Repressão Epigenética , Memória Imunológica , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Elongação Traducional da Cadeia Peptídica , Ribossomos/metabolismo , Tristetraprolina/genética , Tristetraprolina/metabolismo
2.
Nature ; 594(7863): 436-441, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34079128

RESUMO

A delicate equilibrium of WNT agonists and antagonists in the intestinal stem cell (ISC) niche is critical to maintaining the ISC compartment, as it accommodates the rapid renewal of the gut lining. Disruption of this balance by mutations in the tumour suppressor gene APC, which are found in approximately 80% of all human colon cancers, leads to unrestrained activation of the WNT pathway1,2. It has previously been established that Apc-mutant cells have a competitive advantage over wild-type ISCs3. Consequently, Apc-mutant ISCs frequently outcompete all wild-type stem cells within a crypt, thereby reaching clonal fixation in the tissue and initiating cancer formation. However, whether the increased relative fitness of Apc-mutant ISCs involves only cell-intrinsic features or whether Apc mutants are actively involved in the elimination of their wild-type neighbours remains unresolved. Here we show that Apc-mutant ISCs function as bona fide supercompetitors by secreting WNT antagonists, thereby inducing differentiation of neighbouring wild-type ISCs. Lithium chloride prevented the expansion of Apc-mutant clones and the formation of adenomas by rendering wild-type ISCs insensitive to WNT antagonists through downstream activation of WNT by inhibition of GSK3ß. Our work suggests that boosting the fitness of healthy cells to limit the expansion of pre-malignant clones may be a powerful strategy to limit the formation of cancers in high-risk individuals.


Assuntos
Proteína da Polipose Adenomatosa do Colo/genética , Competição entre as Células , Genes APC , Neoplasias Intestinais/genética , Neoplasias Intestinais/patologia , Mutação , Adenoma/genética , Adenoma/metabolismo , Adenoma/patologia , Proteína da Polipose Adenomatosa do Colo/deficiência , Animais , Diferenciação Celular/genética , Feminino , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Humanos , Neoplasias Intestinais/metabolismo , Cloreto de Lítio/farmacologia , Masculino , Camundongos , Organoides/citologia , Organoides/metabolismo , Organoides/patologia , Proteínas Wnt/antagonistas & inibidores , Proteínas Wnt/metabolismo
3.
EMBO J ; 39(18): e103932, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32965059

RESUMO

Wnt/ß-catenin signaling is a primary pathway for stem cell maintenance during tissue renewal and a frequent target for mutations in cancer. Impaired Wnt receptor endocytosis due to loss of the ubiquitin ligase RNF43 gives rise to Wnt-hypersensitive tumors that are susceptible to anti-Wnt-based therapy. Contrary to this paradigm, we identify a class of RNF43 truncating cancer mutations that induce ß-catenin-mediated transcription, despite exhibiting retained Wnt receptor downregulation. These mutations interfere with a ubiquitin-independent suppressor role of the RNF43 cytosolic tail that involves Casein kinase 1 (CK1) binding and phosphorylation. Mechanistically, truncated RNF43 variants trap CK1 at the plasma membrane, thereby preventing ß-catenin turnover and propelling ligand-independent target gene transcription. Gene editing of human colon stem cells shows that RNF43 truncations cooperate with p53 loss to drive a niche-independent program for self-renewal and proliferation. Moreover, these RNF43 variants confer decreased sensitivity to anti-Wnt-based therapy. Our data demonstrate the relevance of studying patient-derived mutations for understanding disease mechanisms and improved applications of precision medicine.


Assuntos
Caseína Quinase I/metabolismo , Neoplasias/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Via de Sinalização Wnt , Caseína Quinase I/genética , Células HEK293 , Humanos , Neoplasias/genética , Neoplasias/patologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/genética , beta Catenina/genética , beta Catenina/metabolismo
4.
J Pathol ; 261(3): 298-308, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37681286

RESUMO

The consensus molecular subtype (CMS) classification divides colorectal cancer (CRC) into four distinct subtypes based on RNA expression profiles. The biological differences between CMSs are already present in CRC precursor lesions, but not all CMSs pose the same risk of malignant transformation. To fully understand the path to malignant transformation and to determine whether CMS is a fixed entity during progression, genomic and transcriptomic data from two regions of the same CRC lesion were compared: the precursor region and the carcinoma region. In total, 24 patients who underwent endoscopic removal of T1-2 CRC were included. Regions were subtyped for CMS and DNA mutation analysis was performed. Additionally, a set of 85 benign adenomas was CMS-subtyped. This analysis revealed that almost all benign adenomas were classified as CMS3 (91.8%). In contrast, CMS2 was the most prevalent subtype in precursor regions (66.7%), followed by CMS3 (29.2%). CMS4 was absent in precursor lesions and originated at the carcinoma stage. Importantly, CMS switching occurred in a substantial number of cases and almost all (six out of seven) CMS3 precursor regions showed a shift to a different subtype in the carcinoma part of the lesion, which in four cases was classified as CMS4. In conclusion, our data indicate that CMS3 is related to a more indolent type of precursor lesion that less likely progresses to CRC and when this occurs, it is often associated with a subtype change that includes the more aggressive mesenchymal CMS4. In contrast, an acquired CMS2 signature appeared to be rather fixed during early CRC development. Combined, our data show that subtype changes occur during progression and that CMS3 switching is related to changes in the genomic background through acquisition of a novel driver mutation (TP53) or selective expansion of a clone, but also occurred independently of such genetic changes. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

5.
Int J Cancer ; 152(3): 511-523, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36069222

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is characterized by abundant stroma, the main cellular constituents of which are cancer-associated fibroblasts (CAFs). Stroma-targeting agents have been proposed to improve the poor outcome of current treatments. However, clinical trials using these agents showed disappointing results. Heterogeneity in the PDAC CAF population was recently delineated demonstrating that both tumor-promoting and tumor-suppressive activities co-exist in the stroma. Here, we aimed to identify biomarkers for the CAF population that contribute to a favorable outcome. RNA-sequencing reads from patient-derived xenografts (PDXs) were mapped to the human and mouse genome to allocate the expression of genes to the tumor or stroma. Survival meta-analysis for stromal genes was performed and applied to human protein atlas data to identify circulating biomarkers. The candidate protein was perturbed in co-cultures and assessed in existing and novel single-cell gene expression analysis from control, pancreatitis, pancreatitis-recovered and PDAC mouse models. Serum levels of the candidate biomarker were measured in two independent cohorts totaling 148 PDAC patients and related them to overall survival. Osteoglycin (OGN) was identified as a candidate serum prognostic marker. Single-cell analysis indicated that Ogn is derived from a subgroup of inflammatory CAFs. Ogn-expressing fibroblasts are distinct from resident healthy pancreatic stellate cells and arise during pancreatitis. Serum OGN levels were prognostic for favorable overall survival in two independent PDAC cohorts (HR = 0.47, P = .042 and HR = 0.53, P = .006). Altogether, we conclude that high circulating OGN levels inform on a previously unrecognized subgroup of CAFs and predict favorable outcomes in resectable PDAC.


Assuntos
Fibroblastos Associados a Câncer , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Pancreatite , Humanos , Camundongos , Animais , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Pancreatite/patologia , Microambiente Tumoral , Neoplasias Pancreáticas
6.
Proc Natl Acad Sci U S A ; 117(41): 25560-25570, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-32989144

RESUMO

Deregulated global mRNA translation is an emerging feature of cancer cells. Oncogenic transformation in colorectal cancer (CRC) is driven by mutations in APC, KRAS, SMAD4, and TP53, known as the adenoma-carcinoma sequence (ACS). Here we introduce each of these driver mutations into intestinal organoids to show that they are modulators of global translational capacity in intestinal epithelial cells. Increased global translation resulting from loss of Apc expression was potentiated by the presence of oncogenic KrasG12D Knockdown of Smad4 further enhanced global translation efficiency and was associated with a lower 4E-BP1-to-eIF4E ratio. Quadruple mutant cells with additional P53 loss displayed the highest global translational capacity, paralleled by high proliferation and growth rates, indicating that the proteome is heavily geared toward cell division. Transcriptional reprogramming facilitating global translation included elevated ribogenesis and activation of mTORC1 signaling. Accordingly, interfering with the mTORC1/4E-BP/eIF4E axis inhibited the growth potential endowed by accumulation of multiple drivers. In conclusion, the ACS is characterized by a strongly altered global translational landscape in epithelial cells, exposing a therapeutic potential for direct targeting of the translational apparatus.


Assuntos
Adenoma/genética , Carcinoma/genética , Mutação/ética , Biossíntese de Proteínas/genética , Adenoma/metabolismo , Animais , Carcinoma/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Células HEK293 , Humanos , Intestinos/citologia , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Camundongos Transgênicos , Organoides/metabolismo , Transdução de Sinais , Técnicas de Cultura de Tecidos
7.
Gut ; 71(1): 119-128, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33436496

RESUMO

OBJECTIVE: Cancer stem cells are responsible for tumour spreading and relapse. Human epidermal growth factor receptor 2 (HER2) expression is a negative prognostic factor in colorectal cancer (CRC) and a potential target in tumours carrying the gene amplification. Our aim was to define the expression of HER2 in colorectal cancer stem cells (CR-CSCs) and its possible role as therapeutic target in CRC resistant to anti- epidermal growth factor receptor (EGFR) therapy. DESIGN: A collection of primary sphere cell cultures obtained from 60 CRC specimens was used to generate CR-CSC mouse avatars to preclinically validate therapeutic options. We also made use of the ChIP-seq analysis for transcriptional evaluation of HER2 activation and global RNA-seq to identify the mechanisms underlying therapy resistance. RESULTS: Here we show that in CD44v6-positive CR-CSCs, high HER2 expression levels are associated with an activation of the phosphatidylinositol 3-kinase (PI3K)/AKT pathway, which promotes the acetylation at the regulatory elements of the Erbb2 gene. HER2 targeting in combination with phosphatidylinositol 3-kinase (PI3K) and mitogen-activated protein kinase kinase (MEK) inhibitors induces CR-CSC death and regression of tumour xenografts, including those carrying Kras and Pik3ca mutation. Requirement for the triple targeting is due to the presence of cancer-associated fibroblasts, which release cytokines able to confer CR-CSC resistance to PI3K/AKT inhibitors. In contrast, targeting of PI3K/AKT as monotherapy is sufficient to kill liver-disseminating CR-CSCs in a model of adjuvant therapy. CONCLUSIONS: While PI3K targeting kills liver-colonising CR-CSCs, the concomitant inhibition of PI3K, HER2 and MEK is required to induce regression of tumours resistant to anti-EGFR therapies. These data may provide a rationale for designing clinical trials in the adjuvant and metastatic setting.


Assuntos
Neoplasias Colorretais/patologia , Fosfatidilinositol 3-Quinase/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Receptor ErbB-2/metabolismo , Animais , Antineoplásicos Imunológicos/farmacologia , Cetuximab/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Humanos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Trastuzumab/farmacologia , Células Tumorais Cultivadas
8.
BMC Cancer ; 22(1): 394, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35413826

RESUMO

BACKGROUND: Recently it has been recognized that stromal markers could be used as a clinically relevant biomarker for therapy response and prognosis. Here, we report on a serum marker for stromal activation, A Disintegrin and Metalloprotease 12 (ADAM12) in colorectal cancer (CRC). METHODS: Using gene expression databases we investigated ADAM12 expression in CRC and delineated the source of ADAM12 expression. The clinical value of ADAM12 was retrospectively assessed in the CAIRO2 trial in metastatic CRC with 235 patients (31% of total cohort), and an independent rectal cancer cohort (n = 20). RESULTS: ADAM12 is expressed by activated CRC associated fibroblasts. In the CAIRO2 trial cohort, ADAM12 serum levels were prognostic (ADAM12 low versus ADAM12 high; median OS 25.3 vs. 17.1 months, HR 1.48 [95% CI 1.11-1.96], P = 0.007). The prognostic potential was specifically high for metastatic rectal cancer (HR 1.78 [95% CI 1.06-3.00], P = 0.030) and mesenchymal subtype tumors (HR 2.12 [95% CI 1.25-3.60], P = 0.004). ADAM12 also showed potential for predicting recurrence in an exploratory analysis of non-metastatic rectal cancers. CONCLUSIONS: Here we describe a non-invasive marker for activated stroma in CRC which associates with poor outcome, especially for primary cancers located in the rectum.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Retais , Proteína ADAM12/genética , Proteína ADAM12/metabolismo , Biomarcadores , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Neoplasias Colorretais/patologia , Humanos , Prognóstico , Estudos Retrospectivos
9.
EMBO Rep ; 21(5): e48780, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32173982

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is characterized by an abundance of stroma. Multiple molecular classification efforts have identified a mesenchymal tumor subtype that is consistently characterized by high-grade growth and poor clinical outcome. The relation between PDAC stroma and tumor subtypes is still unclear. Here, we aimed to identify how PDAC cells instruct the main cellular component of stroma, the pancreatic stellate cells (PSCs). We found in primary tissue that high-grade PDAC had reduced collagen deposition compared to low-grade PDAC. Xenografts and organotypic co-cultures established from mesenchymal-like PDAC cells featured reduced collagen and activated PSC content. Medium transfer experiments using a large set of PDAC cell lines revealed that mesenchymal-like PDAC cells consistently downregulated ACTA2 and COL1A1 expression in PSCs and reduced proliferation. We identified colony-stimulating factor 1 as the mesenchymal PDAC-derived ligand that deactivates PSCs, and inhibition of its receptor CSF1R was able to counteract this effect. In conclusion, high-grade PDAC features stroma that is low in collagen and activated PSC content, and targeting CSF1R offers direct options to maintain a tumor-restricting microenvironment.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Carcinoma Ductal Pancreático/genética , Linhagem Celular Tumoral , Movimento Celular , Humanos , Fator Estimulador de Colônias de Macrófagos/genética , Neoplasias Pancreáticas/genética , Células Estreladas do Pâncreas , Células Estromais , Microambiente Tumoral
10.
Proc Natl Acad Sci U S A ; 116(13): 6140-6145, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30850544

RESUMO

Cancer evolution is predominantly studied by focusing on differences in the genetic characteristics of malignant cells within tumors. However, the spatiotemporal dynamics of clonal outgrowth that underlie evolutionary trajectories remain largely unresolved. Here, we sought to unravel the clonal dynamics of colorectal cancer (CRC) expansion in space and time by using a color-based clonal tracing method. This method involves lentiviral red-green-blue (RGB) marking of cell populations, which enabled us to track individual cells and their clonal outgrowth during tumor initiation and growth in a xenograft model. We found that clonal expansion largely depends on the location of a clone, as small clones reside in the center and large clones mostly drive tumor growth at the border. These dynamics are recapitulated in a computational model, which confirms that the clone position within a tumor rather than cell-intrinsic features, is crucial for clonal outgrowth. We also found that no significant clonal loss occurs during tumor growth and clonal dispersal is limited in most models. Our results imply that, in addition to molecular features of clones such as (epi-)genetic differences between cells, clone location and the geometry of tumor growth are crucial for clonal expansion. Our findings suggest that either microenvironmental signals on the tumor border or differences in physical properties within the tumor, are major contributors to explain heterogeneous clonal expansion. Thus, this study provides further insights into the dynamics of solid tumor growth and progression, as well as the origins of tumor cell heterogeneity in a relevant model system.


Assuntos
Neoplasias Colorretais/patologia , Animais , Linhagem da Célula , Células Clonais , Neoplasias Colorretais/genética , Feminino , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , Transplante de Neoplasias , Análise Espaço-Temporal
11.
Proc Natl Acad Sci U S A ; 116(6): 2237-2242, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30670657

RESUMO

Esophageal adenocarcinoma (EAC) has a dismal prognosis, and survival benefits of recent multimodality treatments remain small. Cancer-associated fibroblasts (CAFs) are known to contribute to poor outcome by conferring therapy resistance to various cancer types, but this has not been explored in EAC. Importantly, a targeted strategy to circumvent CAF-induced resistance has yet to be identified. By using EAC patient-derived CAFs, organoid cultures, and xenograft models we identified IL-6 as the stromal driver of therapy resistance in EAC. IL-6 activated epithelial-to-mesenchymal transition in cancer cells, which was accompanied by enhanced treatment resistance, migratory capacity, and clonogenicity. Inhibition of IL-6 restored drug sensitivity in patient-derived organoid cultures and cell lines. Analysis of patient gene expression profiles identified ADAM12 as a noninflammation-related serum-borne marker for IL-6-producing CAFs, and serum levels of this marker predicted unfavorable responses to neoadjuvant chemoradiation in EAC patients. These results demonstrate a stromal contribution to therapy resistance in EAC. This signaling can be targeted to resensitize EAC to therapy, and its activity can be measured using serum-borne markers.


Assuntos
Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Fibroblastos Associados a Câncer/metabolismo , Resistencia a Medicamentos Antineoplásicos , Transição Epitelial-Mesenquimal , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Interleucina-6/metabolismo , Tolerância a Radiação , Células Estromais/metabolismo , Adenocarcinoma/terapia , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/efeitos da radiação , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Transição Epitelial-Mesenquimal/genética , Neoplasias Esofágicas/terapia , Humanos , Camundongos , Técnicas de Cultura de Tecidos , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Int J Mol Sci ; 23(20)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36293565

RESUMO

The purpose of this study was to evaluate the association between four distinct histopathological features: (1) tumor infiltrating lymphocytes, (2) mucinous differentiation, (3) tumor-stroma ratio, plus (4) tumor budding and two gene expression-based classifiers­(1) consensus molecular subtypes (CMS) plus (2) colorectal cancer intrinsic subtypes (CRIS). All four histopathological features were retrospectively scored on hematoxylin and eosin sections of the most invasive part of the primary tumor in 218 stage II and III colon cancer patients from two independent cohorts (AMC-AJCC-90 and AC-ICAM). RNA-based CMS and CRIS assignments were independently obtained for all patients. Contingency tables were constructed and a χ2 test was used to test for statistical significance. Odds ratios with 95% confidence intervals were calculated. The presence of tumor infiltrating lymphocytes and a mucinous phenotype (>50% mucinous surface area) were strongly correlated with CMS1 (p < 0.001 and p = 0.008) and CRIS-A (p = 0.006 and p < 0.001). The presence of mucus (≥ 10%) was associated with CMS3: mucus was present in 64.1% of all CMS3 tumors (p < 0.001). Although a clear association between tumor-stroma ratio and CMS4 was established in this study (p = 0.006), still 32 out of 61 (52.5%) CMS4 tumors were scored as stroma-low, indicating that CMS4 tumors cannot be identified solely based on stromal content. Higher budding counts were seen in CMS4 and CRIS-B tumors (p = 0.045 and p = 0.046). No other associations of the measured parameters were seen for any of the other CRIS subtypes. Our analysis revealed clear associations between histopathologic features and CMS or CRIS subtypes. However, identification of distinct molecular subtypes solely based on histopathology proved to be infeasible. Combining both molecular and morphologic features could potentially improve patient stratification.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Humanos , Estudos Retrospectivos , Hematoxilina , Amarelo de Eosina-(YS) , Neoplasias do Colo/genética , Neoplasias Colorretais/patologia , Expressão Gênica , RNA , Biomarcadores Tumorais/genética
13.
Nature ; 521(7550): 43-7, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-25924068

RESUMO

Crypt stem cells represent the cells of origin for intestinal neoplasia. Both mouse and human intestinal stem cells can be cultured in medium containing the stem-cell-niche factors WNT, R-spondin, epidermal growth factor (EGF) and noggin over long time periods as epithelial organoids that remain genetically and phenotypically stable. Here we utilize CRISPR/Cas9 technology for targeted gene modification of four of the most commonly mutated colorectal cancer genes (APC, P53 (also known as TP53), KRAS and SMAD4) in cultured human intestinal stem cells. Mutant organoids can be selected by removing individual growth factors from the culture medium. Quadruple mutants grow independently of all stem-cell-niche factors and tolerate the presence of the P53 stabilizer nutlin-3. Upon xenotransplantation into mice, quadruple mutants grow as tumours with features of invasive carcinoma. Finally, combined loss of APC and P53 is sufficient for the appearance of extensive aneuploidy, a hallmark of tumour progression.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Intestinos/patologia , Mutação/genética , Organoides/metabolismo , Organoides/patologia , Células-Tronco/patologia , Aneuploidia , Animais , Sistemas CRISPR-Cas , Criança , Pré-Escolar , Neoplasias Colorretais/metabolismo , Feminino , Genes APC , Genes p53/genética , Xenoenxertos , Humanos , Imidazóis , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Mucosa Intestinal/metabolismo , Camundongos , Pessoa de Meia-Idade , Mutagênese Sítio-Dirigida , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Transplante de Neoplasias , Piperazinas , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proteína Smad4/deficiência , Nicho de Células-Tronco/fisiologia , Células-Tronco/metabolismo
14.
Int J Mol Sci ; 22(8)2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33917026

RESUMO

Colorectal cancer (CRC) is a heterogeneous disease, which in part explains the differential response to chemotherapy observed in the clinic. BH3 mimetics, which target anti-apoptotic BCL-2 family members, have shown potential in the treatment of hematological malignancies and offer promise for the treatment of solid tumors as well. To gain a comprehensive understanding of the response to BH3 mimetics in CRC and the underlying molecular factors predicting sensitivity, we screened a panel of CRC cell lines with four BH3 mimetics targeting distinct anti-apoptotic BCL-2 proteins. Treatment with compounds alone and in combination revealed potent efficacy of combined MCL-1 and BCL-XL inhibition in inducing CRC cell death, irrespective of molecular features. Importantly, expression of the anti-apoptotic protein target of BH3 mimetics on its own did not predict sensitivity. However, the analysis did identify consensus molecular subtype (CMS) specific response patterns, such as higher resistance to single and combined BCL-2 and MCL-1 inhibition in CMS2 cell lines. Furthermore, analysis of mutation status revealed that KRAS mutant cell lines were more resistant to MCL-1 inhibition. Conclusively, we find that CRC cell lines presented with distinct responses to BH3 mimetics that can in part be predicted by their CMS profile and KRAS/BRAF mutations. Overall, almost all CRC lines share sensitivity in the nanomolar range to combined MCL-1 and BCL-XL targeting suggesting that this would be the preferred approach to target these cancers.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/química , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/farmacologia , Biomimética , Mimetismo Molecular , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Neoplasias Colorretais , Relação Dose-Resposta a Droga , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética
15.
Apoptosis ; 25(5-6): 305-320, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32335811

RESUMO

Apoptosis is a form of programmed cell death that is essential for tissue homeostasis. De-regulation of the balance between proliferation and apoptosis contributes to tumor initiation. Particularly in the colon where apoptosis is a crucial process in intestinal turnover, inhibition of apoptosis facilitates transformation and tumor progression. The BCL-2 family of proteins are key regulators of apoptosis and have been implicated in colorectal cancer (CRC) initiation, progression and resistance to therapy. In this review we outline the current knowledge on the BCL-2 family-regulated intrinsic apoptosis pathway and mechanisms by which it is de-regulated in CRC. We further review BH3 mimetics as a therapeutic opportunity to target this pathway and evaluate their potential for CRC treatment.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Apoptose/genética , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/genética , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mimetismo Molecular , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais , Proteína Killer-Antagonista Homóloga a bcl-2/genética , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
16.
Int J Cancer ; 144(2): 366-371, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30151914

RESUMO

Patient-derived xenograft (PDX) models have become an important asset in translational cancer research. However, to provide a robust preclinical platform, PDXs need to accommodate the tumor heterogeneity that is observed in patients. Colorectal cancer (CRC) can be stratified into four consensus molecular subtypes (CMS) with distinct biological and clinical features. Surprisingly, using a set of CRC patients, we revealed the partial representation of tumor heterogeneity in PDX models. The epithelial subtypes, the largest subgroups of CRC subtype, were very ineffective in establishing PDXs, indicating the need for further optimization to develop an effective personalized therapeutic approach to CRC. Moreover, we showed that tumor cell proliferation was associated with successful PDX establishment and able to distinguish patient with poor clinical outcomes within CMS2 group.


Assuntos
Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Xenoenxertos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Animais , Humanos , Camundongos
17.
Int J Cancer ; 145(10): 2792-2803, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31018252

RESUMO

Multimodality treatment has advanced the outcome of esophageal adenocarcinoma (EAC), but overall survival remains poor. Therapeutic pressure activates effective resistance mechanisms and we characterized these mechanisms in response to the currently used neoadjuvant treatment against EAC: carboplatin, paclitaxel and radiotherapy. We developed an in vitro approximation of this regimen and applied it to primary patient-derived cultures. We observed a heterogeneous epithelial-to-mesenchymal (EMT) response to the high therapeutic pressure exerted by chemoradiation. We found EMT to be initiated by the autocrine production and response to transforming growth factor beta (TGF-ß) of EAC cells. Inhibition of TGF-ß ligands effectively abolished chemoradiation-induced EMT. Assessment of TGF-ß serum levels in EAC patients revealed that high levels after neoadjuvant treatment predicted the presence of fluorodeoxyglucose uptake in lymph nodes on the post-chemoradiation positron emission tomography-scan. Our study shows that chemoradiation contributes to resistant metastatic disease in EAC patients by inducing EMT via autocrine TGF-ß production. Monitoring TGF-ß serum levels during treatment could identify those patients at risk of developing metastatic disease, and who would likely benefit from TGF-ß targeting therapy.


Assuntos
Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Neoplasias Esofágicas/terapia , Fator de Crescimento Transformador beta/antagonistas & inibidores , Adenocarcinoma/sangue , Adenocarcinoma/mortalidade , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carboplatina/farmacologia , Carboplatina/uso terapêutico , Linhagem Celular Tumoral , Quimiorradioterapia/métodos , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos/efeitos da radiação , Transição Epitelial-Mesenquimal/efeitos da radiação , Mucosa Esofágica/diagnóstico por imagem , Mucosa Esofágica/patologia , Neoplasias Esofágicas/sangue , Neoplasias Esofágicas/mortalidade , Esofagectomia , Feminino , Fluordesoxiglucose F18 , Humanos , Estimativa de Kaplan-Meier , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Tomografia por Emissão de Pósitrons , Cultura Primária de Células , Intervalo Livre de Progressão , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/efeitos da radiação , Fator de Crescimento Transformador beta/sangue , Fator de Crescimento Transformador beta/metabolismo , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Gastroenterology ; 155(3): 784-798, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29885883

RESUMO

BACKGROUND & AIMS: Immune checkpoint inhibition may affect growth or progression of highly aggressive cancers, such as esophageal adenocarcinoma (EAC). We investigated the regulation of expression of major histocompatibility complex, class 1 (MHC-I) proteins (encoded by HLA-A, HLA-B, and HLA-C) and the immune response to EACs in patient samples. METHODS: We performed quantitative polymerase chain reaction array analyses of OE33 cells and OE19 cells, which express different levels of the ATP binding cassette subfamily B member 1 (TAP1) and TAP2, required for antigen presentation by MHC-I, to identify microRNAs (miRNAs) that regulate their expression. We performed luciferase assays to validate interactions between miRNAs and potential targets. We overexpressed candidate miRNAs in OE33, FLO-1, and OACP4 C cell lines and performed quantitative polymerase chain reaction, immunoblot, and flow cytometry analyses to identify changes in messenger RNA (mRNA) and protein expression; we studied the effects of cytotoxic T cells. We performed miRNA in situ hybridization, RNA-sequencing, and immunohistochemical analyses of tumor tissues from 51 untreated patients with EAC in the Netherlands. Clinical and survival data were collected for patients, and EAC subtypes were determined. RESULTS: We found OE19 cells to have increased levels of 7 miRNAs. Of these, we found binding sites for miRNA 125a (MIR125a)-5p in the 3' untranslated region of the TAP2 mRNA and binding sites for MIR148a-3p in 3' untranslated regions of HLA-A, HLA-B, and HLA-C mRNAs. Overexpression of these miRNAs reduced expression of TAP2 in OE33, FLO-1, and OACP4 C cells, and reduced cell-surface levels of MHC-I. OE33 cells that expressed the viral peptide BZLF1 were killed by cytotoxic T cells, whereas OE33 that overexpressed MIR125a-5p or MIR 148a along with BZLF1 were not. In EAC and nontumor tissues, levels of MIR125a-5p correlated inversely with levels of TAP2 protein. High expression of TAP1 by EAC correlated with significantly shorter overall survival times of patients. EACs that expressed high levels of TAP1 and genes involved in antigen presentation also expressed high levels of genes that regulate the adaptive immune response, PD-L1, PD-L2, and IDO1; these EACs had a poor response to neoadjuvant chemoradiotherapy and associated with shorter overall survival times of patients. CONCLUSIONS: In studies of EAC cell lines and tumor tissues, we found increased levels of MIR125a-5p and MIR148a-3p to reduce levels of TAP2 and MHC-I, required for antigen presentation. High expression of MHC-I molecules by EAC correlated with markers of an adaptive immune response and significantly shorter overall survival times of patients.


Assuntos
Imunidade Adaptativa/genética , Adenocarcinoma/imunologia , Proteínas de Ligação a DNA/imunologia , Neoplasias Esofágicas/imunologia , MicroRNAs/fisiologia , Fatores de Transcrição/imunologia , Regiões 3' não Traduzidas/imunologia , Membro 3 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/imunologia , Adenocarcinoma/genética , Linhagem Celular Tumoral , Neoplasias Esofágicas/genética , Humanos , MicroRNAs/imunologia
19.
Nature ; 553(7686): 37-38, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32086500
20.
Nature ; 553(7686): 37-38, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-29300042
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