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1.
Nat Commun ; 15(1): 4083, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38744825

ABSTRACT

Energetic stress compels cells to evolve adaptive mechanisms to adjust their metabolism. Inhibition of mTOR kinase complex 1 (mTORC1) is essential for cell survival during glucose starvation. How mTORC1 controls cell viability during glucose starvation is not well understood. Here we show that the mTORC1 effectors eukaryotic initiation factor 4E binding proteins 1/2 (4EBP1/2) confer protection to mammalian cells and budding yeast under glucose starvation. Mechanistically, 4EBP1/2 promote NADPH homeostasis by preventing NADPH-consuming fatty acid synthesis via translational repression of Acetyl-CoA Carboxylase 1 (ACC1), thereby mitigating oxidative stress. This has important relevance for cancer, as oncogene-transformed cells and glioma cells exploit the 4EBP1/2 regulation of ACC1 expression and redox balance to combat energetic stress, thereby supporting transformation and tumorigenicity in vitro and in vivo. Clinically, high EIF4EBP1 expression is associated with poor outcomes in several cancer types. Our data reveal that the mTORC1-4EBP1/2 axis provokes a metabolic switch essential for survival during glucose starvation which is exploited by transformed and tumor cells.


Subject(s)
Acetyl-CoA Carboxylase , Adaptor Proteins, Signal Transducing , Cell Cycle Proteins , Cell Survival , Fatty Acids , Glucose , Mechanistic Target of Rapamycin Complex 1 , Mechanistic Target of Rapamycin Complex 1/metabolism , Mechanistic Target of Rapamycin Complex 1/genetics , Glucose/metabolism , Acetyl-CoA Carboxylase/metabolism , Acetyl-CoA Carboxylase/genetics , Humans , Adaptor Proteins, Signal Transducing/metabolism , Adaptor Proteins, Signal Transducing/genetics , Fatty Acids/metabolism , Animals , Cell Cycle Proteins/metabolism , Cell Cycle Proteins/genetics , Mice , NADP/metabolism , Protein Biosynthesis , Phosphoproteins/metabolism , Phosphoproteins/genetics , Oxidative Stress , Cell Line, Tumor , Eukaryotic Initiation Factors/metabolism , Eukaryotic Initiation Factors/genetics
2.
Nat Commun ; 15(1): 3063, 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38594278

ABSTRACT

Programmed cell death ligand 1 (PDL1), as an important biomarker, is quantified by immunohistochemistry (IHC) with few established histopathological patterns. Deep learning aids in histopathological assessment, yet heterogeneity and lacking spatially resolved annotations challenge precise analysis. Here, we present a weakly supervised learning approach using bulk RNA sequencing for PDL1 expression prediction from hematoxylin and eosin (H&E) slides. Our method extends the multiple instance learning paradigm with the teacher-student framework, which assigns dynamic pseudo-labels for intra-slide heterogeneity and retrieves unlabeled instances using temporal ensemble model distillation. The approach, evaluated on 12,299 slides across 20 solid tumor types, achieves a weighted average area under the curve of 0.83 on fresh-frozen and 0.74 on formalin-fixed specimens for 9 tumors with PDL1 as an established biomarker. Our method predicts PDL1 expression patterns, validated by IHC on 20 slides, offering insights into histologies relevant to PDL1. This demonstrates the potential of deep learning in identifying diverse histological patterns for molecular changes from H&E images.


Subject(s)
Distillation , Neoplasms , Humans , Biomarkers , Eosine Yellowish-(YS) , Hematoxylin , Neoplasms/genetics , Students
3.
Cancers (Basel) ; 16(7)2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38611033

ABSTRACT

Sarcomas comprise a heterogeneous group of malignant tumors of mesenchymal origin. More than 80 entities are associated with different mesenchymal lineages. Sarcomas with fibroblastic, muscle, bone, vascular, adipocytic, and other characteristics are distinguished. Nearly half of all entities contain specific chromosomal translocations that give rise to fusion proteins. These are mostly pathognomonic, and their detection by various molecular techniques supports histopathologic classification. Moreover, the fusion proteins act as oncogenic drivers, and their blockade represents a promising therapeutic approach. This review summarizes the current knowledge on fusion proteins in sarcoma. We categorize the different fusion proteins into functional classes, including kinases, epigenetic regulators, and transcription factors, and describe their mechanisms of action. Interestingly, while fusion proteins acting as transcription factors are found in all mesenchymal lineages, the others have a more restricted pattern. Most kinase-driven sarcomas belong to the fibroblastic/myofibroblastic lineage. Fusion proteins with an epigenetic function are mainly associated with sarcomas of unclear differentiation, suggesting that epigenetic dysregulation leads to a major change in cell identity. Comparison of mechanisms of action reveals recurrent functional modes, including antagonism of Polycomb activity by fusion proteins with epigenetic activity and recruitment of histone acetyltransferases by fusion transcription factors of the myogenic lineage. Finally, based on their biology, we describe potential approaches to block the activity of fusion proteins for therapeutic intervention. Overall, our work highlights differences as well as similarities in the biology of fusion proteins from different sarcomas and provides the basis for a functional classification.

4.
Langenbecks Arch Surg ; 409(1): 95, 2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38480587

ABSTRACT

PURPOSE: Improvement of patient care is associated with increasing publication numbers in biomedical research. However, such increasing numbers of publications make it challenging for physicians and scientists to screen and process the literature of their respective fields. In this study, we present a comprehensive bibliometric analysis of the evolution of gastrointestinal stromal tumor (GIST) research, analyzing the current state of the field and identifying key open questions going beyond the recent advantages for future studies to assess. METHODS: Using the Web of Science Core Collection, 5040 GIST-associated publications in the years 1984-2022 were identified and analyzed regarding key bibliometric variables using the Bibliometrix R package and VOSviewer software. RESULTS: GIST-associated publication numbers substantially increased over time, accentuated from year 2000 onwards, and being characterized by multinational collaborations. The main topic clusters comprise surgical management, tyrosine kinase inhibitor (TKI) development/treatment, diagnostic workup, and molecular pathophysiology. Within all main topic clusters, a significant progress is reflected by the literature over the years. This progress ranges from conventional open surgical techniques over minimally invasive, including robotic and endoscopic, resection techniques to increasing identification of specific functional genetic aberrations sensitizing for newly developed TKIs being extensively investigated in clinical studies and implemented in GIST treatment guidelines. However, especially in locally advanced, recurrent, and metastatic disease stages, surgery-related questions and certain specific questions concerning (further-line) TKI treatment resistance were infrequently addressed. CONCLUSION: Increasing GIST-related publication numbers reflect a continuous progress in the major topic clusters of the GIST research field. Especially in advanced disease stages, questions related to the interplay between surgical approaches and TKI treatment sensitivity should be addressed in future studies.


Subject(s)
Antineoplastic Agents , Gastrointestinal Neoplasms , Gastrointestinal Stromal Tumors , Humans , Gastrointestinal Stromal Tumors/surgery , Protein Kinase Inhibitors/therapeutic use , Gastrointestinal Neoplasms/surgery , Antineoplastic Agents/therapeutic use
5.
Nat Commun ; 15(1): 2246, 2024 Mar 12.
Article in English | MEDLINE | ID: mdl-38472236

ABSTRACT

Understanding the molecular and cellular processes involved in lung epithelial regeneration may fuel the development of therapeutic approaches for lung diseases. We combine mouse models allowing diphtheria toxin-mediated damage of specific epithelial cell types and parallel GFP-labeling of functionally dividing cells with single-cell transcriptomics to characterize the regeneration of the distal lung. We uncover cell types, including Krt13+ basal and Krt15+ club cells, detect an intermediate cell state between basal and goblet cells, reveal goblet cells as actively dividing progenitor cells, and provide evidence that adventitial fibroblasts act as supporting cells in epithelial regeneration. We also show that diphtheria toxin-expressing cells can persist in the lung, express specific inflammatory factors, and transcriptionally resemble a previously undescribed population in the lungs of COVID-19 patients. Our study provides a comprehensive single-cell atlas of the distal lung that characterizes early transcriptional and cellular responses to concise epithelial injury, encompassing proliferation, differentiation, and cell-to-cell interactions.


Subject(s)
Diphtheria Toxin , Lung , Mice , Animals , Humans , Diphtheria Toxin/metabolism , Lung/metabolism , Cell Differentiation , Gene Expression Profiling , Cell Division
6.
Int J Mol Sci ; 25(4)2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38396644

ABSTRACT

Germline variants in the FOXE1 transcription factor have been associated with thyroid ectopy, cleft palate (CP) and thyroid cancer (TC). Here, we aimed to clarify the role of FOXE1 in Portuguese families (F1 and F2) with members diagnosed with malignant struma ovarii (MSO), an ovarian teratoma with ectopic malignant thyroid tissue, papillary TC (PTC) and CP. Two rare germline heterozygous variants in the FOXE1 promoter were identified: F1) c.-522G>C, in the proband (MSO) and her mother (asymptomatic); F2) c.9C>T, in the proband (PTC), her sister and her mother (CP). Functional studies using rat normal thyroid (PCCL3) and human PTC (TPC-1) cells revealed that c.9C>T decreased FOXE1 promoter transcriptional activity in both cell models, while c.-522G>C led to opposing activities in the two models, when compared to the wild type. Immunohistochemistry and RT-qPCR analyses of patients' thyroid tumours revealed lower FOXE1 expression compared to adjacent normal and hyperplastic thyroid tissues. The patient with MSO also harboured a novel germline AXIN1 variant, presenting a loss of heterozygosity in its benign and malignant teratoma tissues and observable ß-catenin cytoplasmic accumulation. The sequencing of the F1 (MSO) and F2 (PTC) probands' tumours unveiled somatic BRAF and HRAS variants, respectively. Germline FOXE1 and AXIN1 variants might have a role in thyroid ectopy and cleft palate, which, together with MAPK pathway activation, may contribute to tumours' malignant transformation.


Subject(s)
Cleft Palate , Dermoid Cyst , Forkhead Transcription Factors , Ovarian Neoplasms , Struma Ovarii , Thyroid Neoplasms , Animals , Female , Humans , Rats , Cleft Palate/genetics , Dermoid Cyst/genetics , Forkhead Transcription Factors/genetics , Ovarian Neoplasms/metabolism , Struma Ovarii/genetics , Struma Ovarii/metabolism , Struma Ovarii/pathology , Thyroid Neoplasms/pathology
7.
Horm Metab Res ; 56(1): 38-44, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38171371

ABSTRACT

Testicular adrenal rest tumors (TART) are a frequent and fertility impairing long-term complication in males with classic congenital adrenal hyperplasia. Due to lack of clear experimental data on their origin, they are hypothesized to be derived from ectopic adrenocortical cells within testicular tissue mainly growing upon stimulation by chronically elevated levels of adrenocorticotropin (ACTH). Alternatively, a more totipotent embryological origin has been discussed as the potential source of these tumors. The aim of this study was to quantify alterations of ectopic expression of adrenocortical genes (CYP11B1, CYP11B2, CYP21, MC2R) and the Leydig cell specific marker (INSL3) in testicular tissue of fetal 21-hydroxylase deficient (21OHD) mice. Timed-pregnancy studies were performed using H-2aw18 (aw18)-mice. Testes and adrenals of E15.5 and E18.5 mouse fetuses were used for real-time PCR and immunohistochemistry. Gene expression levels were analyzed for genotype-dependent alterations and compared with immunohistochemistry. While enzymes of steroidogenesis showed a significant increased expression in adrenals of 21OHD mice at both E15.5 and E18.5 compared to wild-type (WT) mice, expression levels were unaltered in testes of 21OHD mice. When compared to WT adrenals a significant increase of INSL3 expression in adrenals of 21OHD mice at E15.5 and E18.5 was detected. Cells with adrenocortical properties in mice fetal testis differ from in situ adrenocortical cells in gene expression and growth at E15.5 and E18.5. These findings suggest that the different local regulation and different local niche in adrenals and testes influence growth of aberrant adrenal cells.


Subject(s)
Adrenal Hyperplasia, Congenital , Testis , Animals , Female , Male , Mice , Pregnancy , Adrenal Hyperplasia, Congenital/genetics , Fetus , Gene Expression , Steroid 21-Hydroxylase/genetics , Steroid 21-Hydroxylase/metabolism , Testis/metabolism
8.
Clin Cancer Res ; 30(6): 1079-1092, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-37916971

ABSTRACT

Epithelioid sarcoma (EpS) is an ultra-rare malignant soft-tissue cancer mostly affecting adolescents and young adults. EpS often exhibits an unfavorable clinical course with fatal outcome in ∼50% of cases despite aggressive multimodal therapies combining surgery, chemotherapy, and irradiation. EpS is traditionally classified in a more common, less aggressive distal (classic) type and a rarer aggressive proximal type. Both subtypes are characterized by a loss of nuclear INI1 expression, most often following homozygous deletion of its encoding gene, SMARCB1-a core subunit of the SWI/SNF chromatin remodeling complex. In 2020, the EZH2 inhibitor tazemetostat was the first targeted therapy approved for EpS, raising new hopes. Still, the vast majority of patients did not benefit from this drug or relapsed rapidly. Further, other recent therapeutic modalities, including immunotherapy, are only effective in a fraction of patients. Thus, novel strategies, specifically targeted to EpS, are urgently needed. To accelerate translational research on EpS and eventually boost the discovery and development of new diagnostic tools and therapeutic options, a vibrant translational research community has formed in past years and held two international EpS digital expert meetings in 2021 and 2023. This review summarizes our current understanding of EpS from the translational research perspective and points to innovative research directions to address the most pressing questions in the field, as defined by expert consensus and patient advocacy groups.


Subject(s)
Sarcoma , Transcription Factors , Adolescent , Young Adult , Humans , Transcription Factors/genetics , DNA-Binding Proteins/genetics , Chromosomal Proteins, Non-Histone/genetics , Homozygote , Consensus , Sequence Deletion , SMARCB1 Protein/genetics , SMARCB1 Protein/metabolism , Sarcoma/diagnosis , Sarcoma/genetics , Sarcoma/therapy
9.
Eur J Surg Oncol ; 49(9): 106948, 2023 09.
Article in English | MEDLINE | ID: mdl-37286428

ABSTRACT

BACKGROUND: Increasing publication numbers in the biomedical field led to an improvement of patient care in many aspects but are challenging for scientists when integratively processing data of their fields. Using bibliometric analyses, the present study assesses the productivity and predominant topics in retroperitoneal soft-tissue sarcoma (RPS) research across the past 122 years, thereby identifying crucial questions to address in future RPS research. METHODS: Using the Web of Science Core Collection, 1018 RPS-associated publications from 1900 to 2022 were identified and analyzed regarding key bibliometric variables using the Bibliometrix R package and the VOSviewer software. RESULTS: A continuous increase in RPS-associated publication numbers can be noticed over the time, which is strongly pronounced from 2005 onwards, and is characterized by a multinationally driven collaborative clinical research focus. The research primarily reflects progression regarding surgical techniques, histology-based therapy, radiotherapy regimens, and identification of prognostic clinicopathological factors. This progression is accompanied with improved overall survival of RPS patients. However, a paucity of RPS-specific basic/translational research indicates that such research might be additionally needed to better understand the pathophysiology of RPS and with that to enable the development of personalized therapies and to further improve patient outcome. CONCLUSION: Increasing publication numbers of multinationally driven clinical RPS research are accompanied with improved overall survival of RPS patients, highlighting the importance of international collaborations to facilitate future clinical trials. However, this bibliometric analysis reveals a lack of RPS-specific basic/translational research which is needed to further improve patient outcome in the context of precision oncology.


Subject(s)
Retroperitoneal Neoplasms , Sarcoma , Soft Tissue Neoplasms , Humans , Precision Medicine , Sarcoma/surgery , Retroperitoneal Neoplasms/surgery , Retrospective Studies , Neoplasm Recurrence, Local/pathology
10.
Mol Cancer ; 22(1): 49, 2023 03 13.
Article in English | MEDLINE | ID: mdl-36915100

ABSTRACT

Hypoxia develops during the growth of solid tumors and influences tumoral activity in multiple ways. Low oxygen tension is also present in the bone microenvironment where Ewing sarcoma (EwS) - a highly aggressive pediatric cancer - mainly arises. Hypoxia inducible factor 1 subunit alpha (HIF-1-a) is the principal molecular mediator of the hypoxic response in cancer whereas EWSR1::FLI1 constitutes the oncogenic driver of EwS. Interaction of the two proteins has been shown in EwS. Although a growing body of studies investigated hypoxia and HIFs in EwS, their precise role for EwS pathophysiology is not clarified to date. This review summarizes and structures recent findings demonstrating that hypoxia and HIFs play a role in EwS at multiple levels. We propose to view hypoxia and HIFs as independent protagonists in the story of EwS and give a perspective on their potential clinical relevance as prognostic markers and therapeutic targets in EwS treatment.


Subject(s)
Sarcoma, Ewing , Humans , Child , Sarcoma, Ewing/genetics , Sarcoma, Ewing/pathology , Oncogene Proteins, Fusion/genetics , Proteins/metabolism , RNA-Binding Protein EWS/genetics , RNA-Binding Protein EWS/metabolism , Hypoxia/genetics , Cell Line, Tumor , Gene Expression Regulation, Neoplastic , Tumor Microenvironment
11.
Nat Cancer ; 4(3): 344-364, 2023 03.
Article in English | MEDLINE | ID: mdl-36732635

ABSTRACT

Metabolic rewiring is often considered an adaptive pressure limiting metastasis formation; however, some nutrients available at distant organs may inherently promote metastatic growth. We find that the lung and liver are lipid-rich environments. Moreover, we observe that pre-metastatic niche formation increases palmitate availability only in the lung, whereas a high-fat diet increases it in both organs. In line with this, targeting palmitate processing inhibits breast cancer-derived lung metastasis formation. Mechanistically, breast cancer cells use palmitate to synthesize acetyl-CoA in a carnitine palmitoyltransferase 1a-dependent manner. Concomitantly, lysine acetyltransferase 2a expression is promoted by palmitate, linking the available acetyl-CoA to the acetylation of the nuclear factor-kappaB subunit p65. Deletion of lysine acetyltransferase 2a or carnitine palmitoyltransferase 1a reduces metastasis formation in lean and high-fat diet mice, and lung and liver metastases from patients with breast cancer show coexpression of both proteins. In conclusion, palmitate-rich environments foster metastases growth by increasing p65 acetylation, resulting in a pro-metastatic nuclear factor-kappaB signaling.


Subject(s)
Lysine Acetyltransferases , NF-kappa B , Mice , Animals , NF-kappa B/metabolism , Carnitine O-Palmitoyltransferase/metabolism , Acetylation , Acetyl Coenzyme A/metabolism , Palmitates , Lysine Acetyltransferases/metabolism
12.
Cell Rep ; 41(10): 111761, 2022 12 06.
Article in English | MEDLINE | ID: mdl-36476851

ABSTRACT

Ewing sarcoma (EwS) is characterized by EWSR1-ETS fusion transcription factors converting polymorphic GGAA microsatellites (mSats) into potent neo-enhancers. Although the paucity of additional mutations makes EwS a genuine model to study principles of cooperation between dominant fusion oncogenes and neo-enhancers, this is impeded by the limited number of well-characterized models. Here we present the Ewing Sarcoma Cell Line Atlas (ESCLA), comprising whole-genome, DNA methylation, transcriptome, proteome, and chromatin immunoprecipitation sequencing (ChIP-seq) data of 18 cell lines with inducible EWSR1-ETS knockdown. The ESCLA shows hundreds of EWSR1-ETS-targets, the nature of EWSR1-ETS-preferred GGAA mSats, and putative indirect modes of EWSR1-ETS-mediated gene regulation, converging in the duality of a specific but plastic EwS signature. We identify heterogeneously regulated EWSR1-ETS-targets as potential prognostic EwS biomarkers. Our freely available ESCLA (http://r2platform.com/escla/) is a rich resource for EwS research and highlights the power of comprehensive datasets to unravel principles of heterogeneous gene regulation by chimeric transcription factors.


Subject(s)
Sarcoma, Ewing , Humans , Sarcoma, Ewing/genetics , Multiomics , Oncogenes , Cell Line , Transcription Factors
14.
Mol Cancer ; 21(1): 199, 2022 10 13.
Article in English | MEDLINE | ID: mdl-36229873

ABSTRACT

Chimeric fusion transcription factors are oncogenic hallmarks of several devastating cancer entities including pediatric sarcomas, such as Ewing sarcoma (EwS) and alveolar rhabdomyosarcoma (ARMS). Despite their exquisite specificity, these driver oncogenes have been considered largely undruggable due to their lack of enzymatic activity.Here, we show in the EwS model that - capitalizing on neomorphic DNA-binding preferences - the addiction to the respective fusion transcription factor EWSR1-FLI1 can be leveraged to express therapeutic genes.We genetically engineered a de novo enhancer-based, synthetic and highly potent expression cassette that can elicit EWSR1-FLI1-dependent expression of a therapeutic payload as evidenced by episomal and CRISPR-edited genomic reporter assays. Combining in silico screens and immunohistochemistry, we identified GPR64 as a highly specific cell surface antigen for targeted transduction strategies in EwS. Functional experiments demonstrated that anti-GPR64-pseudotyped lentivirus harboring our expression cassette can specifically transduce EwS cells to promote the expression of viral thymidine kinase sensitizing EwS for treatment to otherwise relatively non-toxic (Val)ganciclovir and leading to strong anti-tumorigenic, but no adverse effects in vivo. Further, we prove that similar vector designs can be applied in PAX3-FOXO1-driven ARMS, and to express immunomodulatory cytokines, such as IL-15 and XCL1, in tumor entities typically considered to be immunologically 'cold'.Collectively, these results generated in pediatric sarcomas indicate that exploiting, rather than suppressing, the neomorphic functions of chimeric transcription factors may open inroads to innovative and personalized therapies, and that our highly versatile approach may be translatable to other cancers addicted to oncogenic transcription factors with unique DNA-binding properties.


Subject(s)
Sarcoma, Ewing , Sarcoma , Antigens, Surface/therapeutic use , Cell Line, Tumor , Child , DNA , Ganciclovir/therapeutic use , Gene Expression , Gene Expression Regulation, Neoplastic , Humans , Interleukin-15/genetics , Interleukin-15/metabolism , Interleukin-15/therapeutic use , Oncogene Proteins, Fusion/genetics , Oncogene Proteins, Fusion/metabolism , Proto-Oncogene Protein c-fli-1/genetics , Proto-Oncogene Protein c-fli-1/metabolism , RNA-Binding Protein EWS/genetics , RNA-Binding Protein EWS/metabolism , Sarcoma/genetics , Sarcoma, Ewing/drug therapy , Sarcoma, Ewing/therapy , Thymidine Kinase/genetics , Thymidine Kinase/metabolism , Thymidine Kinase/therapeutic use
15.
Nat Rev Dis Primers ; 8(1): 66, 2022 10 06.
Article in English | MEDLINE | ID: mdl-36202860

ABSTRACT

Undifferentiated small round cell sarcomas (SRCSs) of bone and soft tissue comprise a heterogeneous group of highly aggressive tumours associated with a poor prognosis, especially in metastatic disease. SRCS entities mainly occur in the third decade of life and can exhibit striking disparities regarding preferentially affected sex and tumour localization. SRCSs comprise new entities defined by specific genetic abnormalities, namely EWSR1-non-ETS fusions, CIC-rearrangements or BCOR genetic alterations, as well as EWSR1-ETS fusions in the prototypic SRCS Ewing sarcoma. These gene fusions mainly encode aberrant oncogenic transcription factors that massively rewire the transcriptome and epigenome of the as yet unknown cell or cells of origin. Additional mutations or copy number variants are rare at diagnosis and, depending on the tumour entity, may involve TP53, CDKN2A and others. Histologically, these lesions consist of small round cells expressing variable levels of CD99 and specific marker proteins, including cyclin B3, ETV4, WT1, NKX3-1 and aggrecan, depending on the entity. Besides locoregional treatment that should follow standard protocols for sarcoma management, (neo)adjuvant treatment is as yet ill-defined but generally follows that of Ewing sarcoma and is associated with adverse effects that might compromise quality of life. Emerging studies on the molecular mechanisms of SRCSs and the development of genetically engineered animal models hold promise for improvements in early detection, disease monitoring, treatment-related toxicity, overall survival and quality of life.


Subject(s)
Sarcoma, Ewing , Sarcoma, Small Cell , Sarcoma , Aggrecans , Humans , Quality of Life , Sarcoma/diagnosis , Sarcoma/genetics , Sarcoma/therapy , Sarcoma, Ewing/diagnosis , Sarcoma, Small Cell/diagnosis , Sarcoma, Small Cell/genetics , Sarcoma, Small Cell/pathology , Transcription Factors
16.
Nature ; 610(7933): 752-760, 2022 10.
Article in English | MEDLINE | ID: mdl-36070798

ABSTRACT

Establishing and maintaining tolerance to self-antigens or innocuous foreign antigens is vital for the preservation of organismal health. Within the thymus, medullary thymic epithelial cells (mTECs) expressing autoimmune regulator (AIRE) have a critical role in self-tolerance through deletion of autoreactive T cells and promotion of thymic regulatory T (Treg) cell development1-4. Within weeks of birth, a separate wave of Treg cell differentiation occurs in the periphery upon exposure to antigens derived from the diet and commensal microbiota5-8, yet the cell types responsible for the generation of peripheral Treg (pTreg) cells have not been identified. Here we describe the identification of a class of RORγt+ antigen-presenting cells called Thetis cells, with transcriptional features of both mTECs and dendritic cells, comprising four major sub-groups (TC I-TC IV). We uncover a developmental wave of Thetis cells within intestinal lymph nodes during a critical window in early life, coinciding with the wave of pTreg cell differentiation. Whereas TC I and TC III expressed the signature mTEC nuclear factor AIRE, TC IV lacked AIRE expression and was enriched for molecules required for pTreg generation, including the TGF-ß-activating integrin αvß8. Loss of either major histocompatibility complex class II (MHCII) or ITGB8 by Thetis cells led to a profound impairment in intestinal pTreg differentiation, with ensuing colitis. By contrast, MHCII expression by RORγt+ group 3 innate lymphoid cells (ILC3) and classical dendritic cells was neither sufficient nor required for pTreg generation, further implicating TC IV as the tolerogenic RORγt+ antigen-presenting cell with an essential function in early life. Our studies reveal parallel pathways for the establishment of tolerance to self and foreign antigens in the thymus and periphery, respectively, marked by the involvement of shared cellular and transcriptional programmes.


Subject(s)
Antigen-Presenting Cells , Dendritic Cells , Epithelial Cells , Gastrointestinal Microbiome , Immune Tolerance , T-Lymphocytes, Regulatory , Thymus Gland , Cell Differentiation , Dendritic Cells/immunology , Dendritic Cells/metabolism , Epithelial Cells/immunology , Epithelial Cells/metabolism , Gastrointestinal Microbiome/immunology , Immunity, Innate , Nuclear Receptor Subfamily 1, Group F, Member 3/metabolism , Thymus Gland/cytology , Thymus Gland/immunology , Transforming Growth Factor beta/immunology , Antigen-Presenting Cells/immunology , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes, Regulatory/pathology , Lymph Nodes/immunology
17.
Cell Oncol (Dordr) ; 45(6): 1237-1251, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36149602

ABSTRACT

PURPOSE: The relevance of the subfamily A members of ATP-binding cassette (ABCA) transporters as biomarkers of risk and response is emerging in different tumors, but their mechanisms of action have only been partially defined. In this work, we investigated their role in Ewing sarcoma (EWS), a pediatric cancer with unmet clinical issues. METHODS: The expression of ABC members was evaluated by RT-qPCR in patients with localized EWS. The correlation with clinical outcome was established in different datasets using univariate and multivariate statistical methods. Functional studies were conducted in cell lines from patient-derived xenografts (PDXs) using gain- or loss-of-function approaches. The impact of intracellular cholesterol levels and cholesterol lowering drugs on malignant parameters was considered. RESULTS: We found that ABCA6, which is usually poorly expressed in EWS, when upregulated became a prognostic factor of a favorable outcome in patients. Mechanistically, high expression of ABCA6 impaired cell migration and increased cell chemosensitivity by diminishing the intracellular levels of cholesterol and by constitutive IGF1R/AKT/mTOR expression/activation. Accordingly, while exposure of cells to exogenous cholesterol increased AKT/mTOR activation, the cholesterol lowering drug simvastatin inhibited IGF1R/AKT/mTOR signaling and prevented Ser166 phosphorylation of MDM2. This, in turn, favored p53 activation and enhanced pro-apoptotic effects of doxorubicin. CONCLUSIONS: Our study reveals that ABCA6 acts as tumor suppressor in EWS cells via cholesterol-mediated inhibition of IGF1R/AKT/MDM2 signaling, which promotes the pro-apoptotic effects of doxorubicin and reduces cell migration. Our findings also support a role of ABCA6 as biomarker of EWS progression and sustains its assessment for a more rational use of statins as adjuvant drugs.


Subject(s)
ATP-Binding Cassette Transporters , Sarcoma, Ewing , Child , Humans , ATP-Binding Cassette Transporters/metabolism , Cell Line, Tumor , Cholesterol , Doxorubicin/pharmacology , Gene Expression Regulation, Neoplastic , Oncogene Proteins, Fusion/genetics , Proto-Oncogene Proteins c-akt/metabolism , Proto-Oncogene Proteins c-mdm2/metabolism , Receptor, IGF Type 1 , Sarcoma, Ewing/genetics , Sarcoma, Ewing/metabolism , Sarcoma, Ewing/pathology , TOR Serine-Threonine Kinases/metabolism , Animals
18.
NPJ Precis Oncol ; 6(1): 65, 2022 Sep 17.
Article in English | MEDLINE | ID: mdl-36115869

ABSTRACT

The advent of dose intensified interval compressed therapy has improved event-free survival for patients with localized Ewing sarcoma (EwS) to 78% at 5 years. However, nearly a quarter of patients with localized tumors and 60-80% of patients with metastatic tumors suffer relapse and die of disease. In addition, those who survive are often left with debilitating late effects. Clinical features aside from stage have proven inadequate to meaningfully classify patients for risk-stratified therapy. Therefore, there is a critical need to develop approaches to risk stratify patients with EwS based on molecular features. Over the past decade, new technology has enabled the study of multiple molecular biomarkers in EwS. Preliminary evidence requiring validation supports copy number changes, and loss of function mutations in tumor suppressor genes as biomarkers of outcome in EwS. Initial studies of circulating tumor DNA demonstrated that diagnostic ctDNA burden and ctDNA clearance during induction are also associated with outcome. In addition, fusion partner should be a pre-requisite for enrollment on EwS clinical trials, and the fusion type and structure require further study to determine prognostic impact. These emerging biomarkers represent a new horizon in our understanding of disease risk and will enable future efforts to develop risk-adapted treatment.

20.
Int J Mol Sci ; 23(15)2022 08 04.
Article in English | MEDLINE | ID: mdl-35955799

ABSTRACT

Endoglin (ENG) is a mesenchymal stem cell (MSC) marker typically expressed by active endothelium. This transmembrane glycoprotein is shed by matrix metalloproteinase 14 (MMP14). Our previous work demonstrated potent preclinical activity of first-in-class anti-ENG antibody-drug conjugates as a nascent strategy to eradicate Ewing sarcoma (ES), a devastating rare bone/soft tissue cancer with a putative MSC origin. We also defined a correlation between ENG and MMP14 expression in ES. Herein, we show that ENG expression is significantly associated with a dismal prognosis in a large cohort of ES patients. Moreover, both ENG/MMP14 are frequently expressed in primary ES tumors and metastasis. To deepen in their functional relevance in ES, we conducted transcriptomic and proteomic profiling of in vitro ES models that unveiled a key role of ENG and MMP14 in cell mechano-transduction. Migration and adhesion assays confirmed that loss of ENG disrupts actin filament assembly and filopodia formation, with a concomitant effect on cell spreading. Furthermore, we observed that ENG regulates cell-matrix interaction through activation of focal adhesion signaling and protein kinase C expression. In turn, loss of MMP14 contributed to a more adhesive phenotype of ES cells by modulating the transcriptional extracellular matrix dynamics. Overall, these results suggest that ENG and MMP14 exert a significant role in mediating correct spreading machinery of ES cells, impacting the aggressiveness of the disease.


Subject(s)
Bone Neoplasms , Endoglin/metabolism , Sarcoma, Ewing , Bone Neoplasms/genetics , Endoglin/genetics , Humans , Matrix Metalloproteinase 14/genetics , Matrix Metalloproteinase 14/metabolism , Proteomics , Receptors, Growth Factor , Sarcoma, Ewing/pathology , Signal Transduction
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