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1.
J Invest Dermatol ; 143(10): 1937-1946.e7, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37037414

RESUMO

Merkel cell carcinoma (MCC) is an aggressive skin cancer for which Merkel cell polyomavirus integration and expression of viral oncogenes small T and Large T have been identified as major oncogenic determinants. Recently, a component of the PRC2 complex, the histone methyltransferase enhancer of zeste homolog 2 (EZH2) that induces H3K27 trimethylation as a repressive mark has been proposed as a potential therapeutic target in MCC. Because divergent results have been reported for the levels of EZH2 and trimethylation of lysine 27 on histone 3, we analyzed these factors in a large MCC cohort to identify the molecular determinants of EZH2 activity in MCC and to establish MCC cell lines' sensitivity to EZH2 inhibitors. Immunohistochemical expression of EZH2 was observed in 92% of MCC tumors (156 of 170), with higher expression levels in virus-positive than virus-negative tumors (P = 0.026). For the latter, we showed overexpression of EZHIP, a negative regulator of the PRC2 complex. In vitro, ectopic expression of the large T antigen in fibroblasts led to the induction of EZH2 expression, whereas the knockdown of T antigens in MCC cell lines resulted in decreased EZH2 expression. EZH2 inhibition led to selective cytotoxicity on virus-positive MCC cell lines. This study highlights the distinct mechanisms of EZH2 induction between virus-negative and -positive MCC.


Assuntos
Carcinoma de Célula de Merkel , Poliomavírus das Células de Merkel , Neoplasias Cutâneas , Humanos , Carcinoma de Célula de Merkel/patologia , Histonas/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Neoplasias Cutâneas/patologia , Poliomavírus das Células de Merkel/genética , Antígenos Virais de Tumores/genética , Antígenos Virais de Tumores/metabolismo
2.
Cell Mol Immunol ; 20(4): 365-378, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36717657

RESUMO

CD226 has been reported to participate in the rescue of CD8+ T cell dysfunction. In this study, we aimed to assess the prognostic value of CD226 in tumor-infiltrating lymphocytes (TILs) derived from colorectal cancer (CRC) liver metastases treated with chemotherapy and radical surgery. TILs from 43 metastases were isolated and analyzed ex vivo using flow cytometry. CD155 and CD3 levels in the tumor microenvironment were assessed by immunohistochemistry. Exploration and validation of biological processes highlighted in this study were performed by bioinformatics analysis of bulk RNA-seq results for 28 CRC liver metastases pretreated with chemotherapy as well as public gene expression datasets. CD226 expression contributes to the definition of the immune context in CRC liver metastases and primary tumors. CD226 on CD8+ T cells was not specifically coexpressed with other immune checkpoints, such as PD1, TIGIT, and TIM3, in liver metastases. Multivariate Cox regression analysis revealed CD226 expression on CD8+ T cells to be an independent prognostic factor (p = 0.003), along with CD3 density at invasion margins (p = 0.003) and TIGIT expression on CD4+ T cells (p = 0.019). CD155 was not associated with the prognostic value of CD226. Gene expression analysis in a validation dataset confirmed the prognostic value of CD226 in CRC liver metastases but not in primary tumors. Downregulation of CD226 on CD8+ TILs in the liver microenvironment was restored by IL15 treatment. Overall, CD226 expression on liver metastasis-infiltrating CD8+ T cells selectively contributes to immune surveillance of CRC liver metastases and has prognostic value for patients undergoing radical surgery.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Humanos , Linfócitos T CD8-Positivos , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/secundário , Prognóstico , Receptores Imunológicos/metabolismo , Microambiente Tumoral
3.
Oncoimmunology ; 11(1): 2144669, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36387055

RESUMO

Combining immunogenic cell death-inducing chemotherapies and PD-1 blockade can generate remarkable tumor responses. It is now well established that TGF-ß1 signaling is a major component of treatment resistance and contributes to the cancer-related immunosuppressive microenvironment. However, whether TGF-ß1 remains an obstacle to immune checkpoint inhibitor efficacy when immunotherapy is combined with chemotherapy is still to be determined. Several syngeneic murine models were used to investigate the role of TGF-ß1 neutralization on the combinations of immunogenic chemotherapy (FOLFOX: 5-fluorouracil and oxaliplatin) and anti-PD-1. Cancer-associated fibroblasts (CAF) and immune cells were isolated from CT26 and PancOH7 tumor-bearing mice treated with FOLFOX, anti-PD-1 ± anti-TGF-ß1 for bulk and single cell RNA sequencing and characterization. We showed that TGF-ß1 neutralization promotes the therapeutic efficacy of FOLFOX and anti-PD-1 combination and induces the recruitment of antigen-specific CD8+ T cells into the tumor. TGF-ß1 neutralization is required in addition to chemo-immunotherapy to promote inflammatory CAF infiltration, a chemokine production switch in CAF leading to decreased CXCL14 and increased CXCL9/10 production and subsequent antigen-specific T cell recruitment. The immune-suppressive effect of TGF-ß1 involves an epigenetic mechanism with chromatin remodeling of CXCL9 and CXCL10 promoters within CAF DNA in a G9a and EZH2-dependent fashion. Our results strengthen the role of TGF-ß1 in the organization of a tumor microenvironment enriched in myofibroblasts where chromatin remodeling prevents CXCL9/10 production and limits the efficacy of chemo-immunotherapy.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias , Camundongos , Animais , Fibroblastos Associados a Câncer/patologia , Linfócitos T CD8-Positivos , Imunoterapia/métodos , Quimiocinas/uso terapêutico , Neoplasias/tratamento farmacológico , Microambiente Tumoral
4.
Methods Mol Biol ; 2543: 167-178, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36087267

RESUMO

Proximity ligation in situ assay (PLISA) is a powerful method to quantify endogen protein-protein interactions in cells and simultaneously identify localization of these interactions. PLISA can be used to quantify autophagy flux and can as well be adapted to assess global autophagy (SQSTM1/P62-LC3B interaction) or specific autophagy, such as mitophagy (NIX-LC3B). Here, we describe a step-by-step method to monitor autophagy using PLISA in adherent cancer cells.


Assuntos
Autofagia , Neoplasias , Proteínas Relacionadas à Autofagia/metabolismo , Mitofagia , Proteína Sequestossoma-1/metabolismo
5.
J Virol ; 96(10): e0187521, 2022 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-35475668

RESUMO

Persistent infection with some mucosal α-genus human papillomaviruses (HPVs; the most prevalent one being HPV16) can induce cervical carcinoma, anogenital cancers, and a subset of head and neck squamous cell carcinoma (HNSCC). Cutaneous ß-genus HPVs (such as HPV5 and HPV8) associate with skin lesions that can progress into squamous cell carcinoma with sun exposure in Epidermodysplasia verruciformis patients and immunosuppressed patients. Here, we analyzed mechanisms used by E6 proteins from the α- and ß-genus to inhibit the interferon-ß (IFNB1) response. HPV16 E6 mediates this effect by a strong direct interaction with interferon regulatory factor 3 (IRF3). The binding site of E6 was localized within a flexible linker between the DNA-binding domain and the IRF-activation domain of IRF3 containing an LxxLL motif. The crystallographic structure of the complex between HPV16 E6 and the LxxLL motif of IRF3 was solved and compared with the structure of HPV16 E6 interacting with the LxxLL motif of the ubiquitin ligase E6AP. In contrast, cutaneous HPV5 and HPV8 E6 proteins bind to the IRF3-binding domain (IBiD) of the CREB-binding protein (CBP), a key transcriptional coactivator in IRF3-mediated IFN-ß expression. IMPORTANCE Persistent HPV infections can be associated with the development of several cancers. The ability to persist depends on the ability of the virus to escape the host immune system. The type I interferon (IFN) system is the first-line antiviral defense strategy. HPVs carry early proteins that can block the activation of IFN-I. Among mucosal α-genus HPV types, the HPV16 E6 protein has a remarkable property to strongly interact with the transcription factor IRF3. Instead, cutaneous HPV5 and HPV8 E6 proteins bind to the IRF3 cofactor CBP. These results highlight the versatility of E6 proteins to interact with different cellular targets. The interaction between the HPV16 E6 protein and IRF3 might contribute to the higher prevalence of HPV16 than that of other high-risk mucosal HPV types in HPV-associated cancers.


Assuntos
Fator Regulador 3 de Interferon , Interferon beta , Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Proteínas Repressoras , Papillomavirus Humano 16/metabolismo , Humanos , Fator Regulador 3 de Interferon/genética , Fator Regulador 3 de Interferon/metabolismo , Interferon beta/metabolismo , Mucosa/virologia , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Papillomaviridae/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Pele/virologia
6.
Nat Commun ; 13(1): 1076, 2022 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-35228537

RESUMO

Despite the high prevalence of both cervico-vaginal human papillomavirus (HPV) infection and bacterial vaginosis (BV) worldwide, their causal relationship remains unclear. While BV has been presumed to be a risk factor for HPV acquisition and related carcinogenesis for a long time, here, supported by both a large retrospective follow-up study (n = 6,085) and extensive in vivo data using the K14-HPV16 transgenic mouse model, we report a novel blueprint in which the opposite association also exists. Mechanistically, by interacting with several core members (NEMO, CK1 and ß-TrCP) of both NF-κB and Wnt/ß-catenin signaling pathways, we show that HPV E7 oncoprotein greatly inhibits host defense peptide expression. Physiologically secreted by the squamous mucosa lining the lower female genital tract, we demonstrate that some of these latter are fundamental factors governing host-microbial interactions. More specifically, several innate molecules down-regulated in case of HPV infection are hydrolyzed, internalized and used by the predominant Lactobacillus species as amino acid source sustaining their growth/survival. Collectively, this study reveals a new viral immune evasion strategy which, by its persistent/negative impact on lactic acid bacteria, ultimately causes the dysbiosis of vaginal microbiota.


Assuntos
Microbiota , Infecções por Papillomavirus , Vaginose Bacteriana , Aminoácidos , Animais , Feminino , Seguimentos , Lactobacillus/fisiologia , Camundongos , Microbiota/fisiologia , Mucosa , Peptídeos , Estudos Retrospectivos , Vagina/microbiologia , Vaginose Bacteriana/microbiologia
7.
Nat Commun ; 12(1): 6648, 2021 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-34789764

RESUMO

The U6 snRNA, the core catalytic component of the spliceosome, is extensively modified post-transcriptionally, with 2'-O-methylation being most common. However, how U6 2'-O-methylation is regulated remains largely unknown. Here we report that TFIP11, the human homolog of the yeast spliceosome disassembly factor Ntr1, localizes to nucleoli and Cajal Bodies and is essential for the 2'-O-methylation of U6. Mechanistically, we demonstrate that TFIP11 knockdown reduces the association of U6 snRNA with fibrillarin and associated snoRNAs, therefore altering U6 2'-O-methylation. We show U6 snRNA hypomethylation is associated with changes in assembly of the U4/U6.U5 tri-snRNP leading to defects in spliceosome assembly and alterations in splicing fidelity. Strikingly, this function of TFIP11 is independent of the RNA helicase DHX15, its known partner in yeast. In sum, our study demonstrates an unrecognized function for TFIP11 in U6 snRNP modification and U4/U6.U5 tri-snRNP assembly, identifying TFIP11 as a critical spliceosome assembly regulator.


Assuntos
Fatores de Processamento de RNA/metabolismo , Splicing de RNA/fisiologia , RNA Nuclear Pequeno/metabolismo , Ribonucleoproteína Nuclear Pequena U4-U6/metabolismo , Ribonucleoproteína Nuclear Pequena U5/metabolismo , Nucléolo Celular/metabolismo , Sobrevivência Celular , Corpos Enovelados/metabolismo , Células HeLa , Humanos , Metilação , Mitose , Proteínas Nucleares/metabolismo , Salpicos Nucleares/metabolismo , Ligação Proteica , Estabilidade Proteica , Precursores de RNA/metabolismo , Fatores de Processamento de RNA/genética , RNA Nucleolar Pequeno/metabolismo , Spliceossomos/metabolismo
8.
Biomedicines ; 9(10)2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34680418

RESUMO

EMT is a reversible cellular process that is linked to gene expression reprogramming, which allows for epithelial cells to undergo a phenotypic switch to acquire mesenchymal properties. EMT is associated with cancer progression and cancer therapeutic resistance and it is known that, during the EMT, many stress response pathways, such as autophagy and NMD, are dysregulated. Therefore, our goal was to study the regulation of ATG8 family members (GABARAP, GABARAPL1, LC3B) by the NMD and to identify molecular links between these two cellular processes that are involved in tumor development and metastasis formation. IHC experiments, which were conducted in a cohort of patients presenting lung adenocarcinomas, showed high GABARAPL1 and low UPF1 levels in EMT+ tumors. We observed increased levels of GABARAPL1 correlated with decreased levels of NMD factors in A549 cells in vitro. We then confirmed that GABARAPL1 mRNA was indeed targeted by the NMD in a 3'UTR-dependent manner and we identified four overlapping binding sites for UPF1 and eIF4A3 that are potentially involved in the recognition of this transcript by the NMD pathway. Our study suggests that 3'UTR-dependent NMD might be an important mechanism that is involved in the induction of autophagy and could represent a promising target in the development of new anti-cancer therapies.

9.
Biology (Basel) ; 10(10)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34681055

RESUMO

The pathway of selective autophagy, leading to a targeted elimination of specific intracellular components, is mediated by the ATG8 proteins, and has been previously suggested to be involved in the regulation of the Epithelial-mesenchymal transition (EMT) during cancer's etiology. However, the molecular factors and steps of selective autophagy occurring during EMT remain unclear. We therefore analyzed a cohort of lung adenocarcinoma tumors using transcriptome analysis and immunohistochemistry, and found that the expression of ATG8 genes is correlated with that of EMT-related genes, and that GABARAPL1 protein levels are increased in EMT+ tumors compared to EMT- ones. Similarly, the induction of EMT in the A549 lung adenocarcinoma cell line using TGF-ß/TNF-α led to a high increase in GABARAPL1 expression mediated by the EMT-related transcription factors of the SMAD family, whereas the other ATG8 genes were less modified. To determine the role of GABARAPL1 during EMT, we used the CRISPR/Cas9 technology in A549 and ACHN kidney adenocarcinoma cell lines to deplete GABARAPL1. We then observed that GABARAPL1 knockout induced EMT linked to a defect of GABARAPL1-mediated degradation of the SMAD proteins. These findings suggest that, during EMT, GABARAPL1 might intervene in an EMT-regulatory loop. Indeed, induction of EMT led to an increase in GABARAPL1 levels through the activation of the SMAD signaling pathway, and then GABARAPL1 induced the autophagy-selective degradation of SMAD proteins, leading to EMT inhibition.

10.
BMC Cancer ; 21(1): 1092, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34627187

RESUMO

BACKGROUND: In oncology, liquid biopsy is of major relevance from theranostic point of view. The searching for mutations in circulating tumor DNA (ctDNA) in case of colorectal cancers (CRCs) allows the optimization of patient care. In this context, independent of mutation status biomarkers are required for its detection to confirm the presence of ctDNA in liquid biopsies. Indeed, the hypermethylation of NPY and WIF1 genes appear to be an ideal biomarker for the specific detection of ctDNA in CRCs. The objective of this work is to develop the research of hypermethylation of NPY and WIF1 by Crystal Digital PCR™ for the detection of ctDNA in CRCs. METHODS: Detection of hypermethylated NPY and WIF1 was developed on Cristal digital PCR™. Biological validation was performed from a local cohort of 22 liquid biopsies and 23 tissue samples from patients with CRC. These patients were treated at the University Hospital of Besancon (France). RESULTS: The local cohort study confirmed that NPY and WIF1 were significantly hypermethylated in tumor tissues compared to adjacent non-tumor tissues (WIF1 p < 0.001; NPY p < 0.001; non-parametric Wilcoxon paired-series test). Histological characteristics, tumor stages or mutation status were not correlated to the methylation profiles. On the other hand, hypermethylation of NPY or WIF1 in liquid biopsy had a 95.5% [95%CI 77-100%] sensitivity and 100% [95%CI 69-100%] specificity. CONCLUSION: Using Crystal digital PCR™, this study shows that hypermethylation of NPY and WIF1 are constant specific biomarkers of CRCs regardless of a potential role in carcinogenesis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , DNA Tumoral Circulante/genética , Neoplasias Colorretais/genética , Metilação de DNA , Neuropeptídeo Y/genética , Reação em Cadeia da Polimerase/métodos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , DNA Tumoral Circulante/sangue , Neoplasias Colorretais/sangue , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/patologia , Intervalos de Confiança , Feminino , Marcadores Genéticos , Humanos , Biópsia Líquida , Masculino , Pessoa de Meia-Idade , Neuropeptídeo Y/metabolismo , Sensibilidade e Especificidade
11.
Front Immunol ; 12: 669992, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34262562

RESUMO

Evidences highlight the role of various CD4+ helper T cells (CD4+ Th) subpopulations in orchestrating the immune responses against cancers. Epigenetics takes an important part in the regulation of CD4+ Th polarization and plasticity. In this review, we described the epigenetic factors that govern CD4+ T cells differentiation and recruitment in the tumor microenvironment and their subsequent involvement in the antitumor immunity. Finally, we discussed how to manipulate tumor reactive CD4+ Th responses by epigenetic drugs to improve anticancer immunotherapy.


Assuntos
Antineoplásicos/uso terapêutico , Reprogramação Celular/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Imunoterapia Adotiva , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Neoplasias/terapia , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Linfócitos T Auxiliares-Indutores/transplante , Animais , Antineoplásicos/efeitos adversos , Diferenciação Celular/efeitos dos fármacos , Humanos , Imunoterapia Adotiva/efeitos adversos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo , Resultado do Tratamento , Microambiente Tumoral
12.
Biomolecules ; 11(6)2021 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-34067395

RESUMO

Epithelial to mesenchymal transition (EMT) is a process that allows epithelial cells to progressively acquire a reversible mesenchymal phenotype. Here, we recount the main events in the history of EMT. EMT was first studied during embryonic development. Nowadays, it is an important field in cancer research, studied all around the world by more and more scientists, because it was shown that EMT is involved in cancer aggressiveness in many different ways. The main features of EMT's involvement in embryonic development, fibrosis and cancers are briefly reviewed here.


Assuntos
Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário , Transição Epitelial-Mesenquimal , Neoplasias/metabolismo , Animais , Humanos
13.
J Transl Med ; 19(1): 265, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-34154602

RESUMO

BACKGROUND: Genetically engineered chimeric antigen receptor (CAR) T lymphocytes are promising therapeutic tools for cancer. Four CAR T cell drugs, including tisagenlecleucel (tisa-cel) and axicabtagene-ciloleucel (axi-cel), all targeting CD19, are currently approved for treating B cell malignancies. Flow cytometry (FC) remains the standard for monitoring CAR T cells using a recombinant biotinylated target protein. Nevertheless, there is a need for additional tools, and the challenge is to develop an easy, relevant, highly sensitive, reproducible, and inexpensive detection method. Molecular tools can meet this need to specifically monitor long-term persistent CAR T cells. METHODS: Based on 2 experimental CAR T cell constructs, IL-1RAP and CS1, we designed 2 quantitative digital droplet (ddPCR) PCR assays. By targeting the 4.1BB/CD3z (28BBz) or 28/CD3z (28z) junction area, we demonstrated that PCR assays can be applied to approved CD19 CAR T drugs. Both 28z and 28BBz ddPCR assays allow determination of the average vector copy number (VCN) per cell. We confirmed that the VCN is dependent on the multiplicity of infection and verified that the VCN of our experimental or GMP-like IL-1RAP CAR T cells met the requirement (< 5 VCN/cell) for delivery to the clinical department, similar to approved axi-cel or tisa-cel drugs. RESULTS: 28BBz and 28z ddPCR assays applied to 2 tumoral (acute myeloid leukemia (AML) or multiple myeloma (MM) xenograft humanized NSG mouse models allowed us to quantify the early expansion (up to day 30) of CAR T cells after injection. Interestingly, following initial expansion, when circulating CAR T cells were challenged with the tumor, we noted a second expansion phase. Investigation of the bone marrow, spleen and lung showed that CAR T cells disseminated more within these tissues in mice previously injected with leukemic cell lines. Finally, circulating CAR T cell ddPCR monitoring of R/R acute lymphoid leukemia or diffuse large B cell lymphoma (n = 10 for tisa-cel and n = 7 for axi-cel) patients treated with both approved CAR T cells allowed detection of early expansion, which was highly correlated with FC, as well as long-term persistence (up to 450 days), while FC failed to detect these events. CONCLUSION: Overall, we designed and validated 2 ddPCR assays allowing routine or preclinical monitoring of early- and long-term circulating approved or experimental CAR T cells, including our own IL-1RAP CAR T cells, which will be evaluated in an upcoming phase I clinical trial.


Assuntos
Variações do Número de Cópias de DNA , Linfoma Difuso de Grandes Células B , Animais , Antígenos CD19 , Xenoenxertos , Humanos , Imunoterapia Adotiva , Camundongos , Reação em Cadeia da Polimerase , Linfócitos T
14.
Cancer Res ; 81(13): 3664-3678, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33985973

RESUMO

Androgen deprivation therapy (ADT) is the standard of care for treatment of nonresectable prostate cancer. Despite high treatment efficiency, most patients ultimately develop lethal castration-resistant prostate cancer (CRPC). In this study, we performed a comparative proteomic analysis of three in vivo, androgen receptor (AR)-responsive orthograft models of matched hormone-naïve prostate cancer and CRPC. Differential proteomic analysis revealed that distinct molecular mechanisms, including amino acid (AA) and fatty acid metabolism, are involved in the response to ADT in the different models. Despite this heterogeneity, Schlafen family member 5 (SLFN5) was identified as an AR-regulated protein in CRPC. SLFN5 expression was high in CRPC tumors and correlated with poor patient outcome. In vivo, SLFN5 depletion strongly impaired tumor growth in castrated conditions. Mechanistically, SLFN5 interacted with ATF4 and regulated the expression of LAT1, an essential AA transporter. Consequently, SLFN5 depletion in CRPC cells decreased intracellular levels of essential AA and impaired mTORC1 signaling in a LAT1-dependent manner. These results confirm that these orthograft models recapitulate the high degree of heterogeneity observed in patients with CRPC and further highlight SLFN5 as a clinically relevant target for CRPC. SIGNIFICANCE: This study identifies SLFN5 as a novel regulator of the LAT1 amino acid transporter and an essential contributor to mTORC1 activity in castration-resistant prostate cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , Proteínas de Ciclo Celular/metabolismo , Regulação Neoplásica da Expressão Gênica , Transportador 1 de Aminoácidos Neutros Grandes/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , Serina-Treonina Quinases TOR/metabolismo , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/genética , Proteínas de Ciclo Celular/genética , Proliferação de Células , Humanos , Transportador 1 de Aminoácidos Neutros Grandes/genética , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Metaboloma , Camundongos , Camundongos Nus , Prognóstico , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/metabolismo , Proteoma , Taxa de Sobrevida , Serina-Treonina Quinases TOR/genética , Transcriptoma , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Cancer Immunol Res ; 9(3): 324-336, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33419764

RESUMO

It is clearly established that the immune system can affect cancer response to therapy. However, the influence of the tumor microenvironment (TME) on immune cells is not completely understood. In this respect, alternative splicing is increasingly described to affect the immune system. Here, we showed that the TME, via a TGFß-dependent mechanism, increased alternative splicing events and induced the expression of an alternative isoform of the IRF1 transcription factor (IRF1Δ7) in Th1 cells. We found that the SFPQ splicing factor (splicing factor, proline- and glutamine-rich) was responsible for the IRF1Δ7 production. We also showed, in both mice and humans, that the IRF1 alternative isoform altered the full-length IRF1 transcriptional activity on the Il12rb1 promoter, resulting in decreased IFNγ secretion in Th1 cells. Thus, the IRF1Δ7 isoform was increased in the TME, and inhibiting IRF1Δ7 expression could potentiate Th1 antitumor responses.


Assuntos
Fator Regulador 1 de Interferon/genética , Interferon gama/metabolismo , Neoplasias/imunologia , Processamento Alternativo , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica/imunologia , Técnicas de Silenciamento de Genes , Humanos , Fator Regulador 1 de Interferon/metabolismo , Camundongos , Neoplasias/genética , Neoplasias/patologia , Regiões Promotoras Genéticas , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Precursores de RNA/metabolismo , RNA Mensageiro/metabolismo , RNA-Seq , Receptores de Interleucina-12 , Células Th1/imunologia , Células Th1/metabolismo , Evasão Tumoral/genética , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
16.
Cancers (Basel) ; 12(12)2020 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-33291363

RESUMO

The role of Epigenetics in Epithelial Mesenchymal Transition (EMT) has recently emerged. Two epigenetic enzymes with paradoxical roles have previously been associated to EMT, EZH2 (Enhancer of Zeste 2 Polycomb Repressive Complex 2 (PRC2) Subunit), a lysine methyltranserase able to add the H3K27me3 mark, and the histone demethylase KDM6B (Lysine Demethylase 6B), which can remove the H3K27me3 mark. Nevertheless, it still remains unclear how these enzymes, with apparent opposite activities, could both promote EMT. In this study, we evaluated the function of these two enzymes using an EMT-inducible model, the lung cancer A549 cell line. ChIP-seq coupled with transcriptomic analysis showed that EZH2 and KDM6B were able to target and modulate the expression of different genes during EMT. Based on this analysis, we described INHBB, WTN5B, and ADAMTS6 as new EMT markers regulated by epigenetic modifications and directly implicated in EMT induction.

17.
Int J Mol Sci ; 21(20)2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33066397

RESUMO

Due to the spectacular number of studies focusing on epigenetics in the last few decades, and particularly for the last few years, the availability of a chronology of epigenetics appears essential. Indeed, our review places epigenetic events and the identification of the main epigenetic writers, readers and erasers on a historic scale. This review helps to understand the increasing knowledge in molecular and cellular biology, the development of new biochemical techniques and advances in epigenetics and, more importantly, the roles played by epigenetics in many physiological and pathological situations.


Assuntos
Epigênese Genética , Epigenômica/história , Animais , Metilação de DNA , História do Século XX , História do Século XXI , Humanos , Processamento de Proteína Pós-Traducional
18.
Nat Commun ; 11(1): 2508, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32427840

RESUMO

Despite the clinical success of Androgen Receptor (AR)-targeted therapies, reactivation of AR signalling remains the main driver of castration-resistant prostate cancer (CRPC) progression. In this study, we perform a comprehensive unbiased characterisation of LNCaP cells chronically exposed to multiple AR inhibitors (ARI). Combined proteomics and metabolomics analyses implicate an acquired metabolic phenotype common in ARI-resistant cells and associated with perturbed glucose and lipid metabolism. To exploit this phenotype, we delineate a subset of proteins consistently associated with ARI resistance and highlight mitochondrial 2,4-dienoyl-CoA reductase (DECR1), an auxiliary enzyme of beta-oxidation, as a clinically relevant biomarker for CRPC. Mechanistically, DECR1 participates in redox homeostasis by controlling the balance between saturated and unsaturated phospholipids. DECR1 knockout induces ER stress and sensitises CRPC cells to ferroptosis. In vivo, DECR1 deletion impairs lipid metabolism and reduces CRPC tumour growth, emphasizing the importance of DECR1 in the development of treatment resistance.


Assuntos
Metabolismo dos Lipídeos , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Neoplasias de Próstata Resistentes à Castração/enzimologia , Antagonistas de Receptores de Andrógenos/administração & dosagem , Progressão da Doença , Homeostase , Humanos , Masculino , Mitocôndrias/enzimologia , Mitocôndrias/genética , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Fosfolipídeos/metabolismo , Próstata/enzimologia , Próstata/metabolismo , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo
19.
Int J Mol Sci ; 21(5)2020 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-32121394

RESUMO

Th17 cells represent a subset of CD4+ T cells characterized by the master transcription factor RORγt and the production of IL-17. Epigenetic modifications such as post-translational histone modifications and DNA methylation play a key role in Th17 cell differentiation and high plasticity. Th17 cells are highly recruited in many types of cancer and can be associated with good or bad prognosis. Here, we will review the remodeling of the epigenome induced by the tumor microenvironment, which may explain Th17 cell predominance. We will also discuss the promising treatment perspectives of molecules targeting epigenetic enzymes to remodel a Th17-enriched tumor microenvironment.


Assuntos
Epigênese Genética , Neoplasias/imunologia , Células Th17/imunologia , Microambiente Tumoral/imunologia , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias/genética , Neoplasias/patologia , Células Th17/metabolismo , Células Th17/patologia
20.
Genes Cancer ; 11(3-4): 154-168, 2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33488952

RESUMO

Previous works have described that autophagy could be associated to both pro- and anti-cancer properties according to numerous factors, such as the gene considered, the step of autophagy involved or the cancer model used. These data might be explained by the fact that some autophagy-related genes may be involved in other cellular processes and therefore differently regulated according to the type or the grade of the tumor. Indeed, using different approaches of transcriptome analysis in breast cancers, and further confirmation using digital PCR, we identified a specific signature of autophagy gene expression associated to Luminal A or Triple Negative Breast Cancers (TNBC). Moreover, we confirmed that ATG5, an autophagy gene specifically expressed in TNBC, favored cell migration, whereas BECN1, an autophagy gene specifically associated with ER-positive breast cancers, induced opposite effects. We also showed that overall inhibition of autophagy promoted cell migration suggesting that the role of individual ATG genes in cancer phenotypes was not strictly dependent of their function during autophagy. Finally, our work led to the identification of TXNIP1 as a potential biomarker associated to autophagy induction in breast cancers. This gene could become an essential tool to quantify autophagy levels in fixed biopsies, sort tumors according to their autophagy levels and determine the best therapeutic treatment.

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