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1.
Cell ; 158(1): 157-70, 2014 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-24976009

RESUMO

The Hippo transducers YAP/TAZ have been shown to play positive, as well as negative, roles in Wnt signaling, but the underlying mechanisms remain unclear. Here, we provide biochemical, functional, and genetic evidence that YAP and TAZ are integral components of the ß-catenin destruction complex that serves as cytoplasmic sink for YAP/TAZ. In Wnt-ON cells, YAP/TAZ are physically dislodged from the destruction complex, allowing their nuclear accumulation and activation of Wnt/YAP/TAZ-dependent biological effects. YAP/TAZ are required for intestinal crypt overgrowth induced by APC deficiency and for crypt regeneration ex vivo. In Wnt-OFF cells, YAP/TAZ are essential for ß-TrCP recruitment to the complex and ß-catenin inactivation. In Wnt-ON cells, release of YAP/TAZ from the complex is instrumental for Wnt/ß-catenin signaling. In line, the ß-catenin-dependent maintenance of ES cells in an undifferentiated state is sustained by loss of YAP/TAZ. This work reveals an unprecedented signaling framework relevant for organ size control, regeneration, and tumor suppression.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Fosfoproteínas/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Aciltransferases , Animais , Proteínas de Ciclo Celular , Linhagem Celular , Células-Tronco Embrionárias/metabolismo , Células HEK293 , Humanos , Camundongos , Modelos Biológicos , Proteínas de Sinalização YAP
2.
Nature ; 607(7920): 790-798, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35768505

RESUMO

Ageing is intimately connected to the induction of cell senescence1,2, but why this is so remains poorly understood. A key challenge is the identification of pathways that normally suppress senescence, are lost during ageing and are functionally relevant to oppose ageing3. Here we connected the structural and functional decline of ageing tissues to attenuated function of the master effectors of cellular mechanosignalling YAP and TAZ. YAP/TAZ activity declines during physiological ageing in stromal cells, and mimicking such decline through genetic inactivation of YAP/TAZ in these cells leads to accelerated ageing. Conversely, sustaining YAP function rejuvenates old cells and opposes the emergence of ageing-related traits associated with either physiological ageing or accelerated ageing triggered by a mechano-defective extracellular matrix. Ageing traits induced by inactivation of YAP/TAZ are preceded by induction of tissue senescence. This occurs because YAP/TAZ mechanotransduction suppresses cGAS-STING signalling, to the extent that inhibition of STING prevents tissue senescence and premature ageing-related tissue degeneration after YAP/TAZ inactivation. Mechanistically, YAP/TAZ-mediated control of cGAS-STING signalling relies on the unexpected role of YAP/TAZ in preserving nuclear envelope integrity, at least in part through direct transcriptional regulation of lamin B1 and ACTR2, the latter of which is involved in building the peri-nuclear actin cap. The findings demonstrate that declining YAP/TAZ mechanotransduction drives ageing by unleashing cGAS-STING signalling, a pillar of innate immunity. Thus, sustaining YAP/TAZ mechanosignalling or inhibiting STING may represent promising approaches for limiting senescence-associated inflammation and improving healthy ageing.


Assuntos
Envelhecimento , Proteínas de Membrana , Nucleotidiltransferases , Células Estromais , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Proteínas de Sinalização YAP , Proteína 2 Relacionada a Actina/metabolismo , Envelhecimento/metabolismo , Senescência Celular , Matriz Extracelular , Envelhecimento Saudável , Imunidade Inata , Lamina Tipo B/metabolismo , Mecanotransdução Celular/genética , Proteínas de Membrana/metabolismo , Membrana Nuclear/metabolismo , Nucleotidiltransferases/metabolismo , Transdução de Sinais , Células Estromais/metabolismo , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional/antagonistas & inibidores , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional/metabolismo , Proteínas de Sinalização YAP/antagonistas & inibidores , Proteínas de Sinalização YAP/metabolismo
3.
Cell ; 141(7): 1195-207, 2010 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-20603000

RESUMO

Although specific microRNAs (miRNAs) can be upregulated in cancer, global miRNA downregulation is a common trait of human malignancies. The mechanisms of this phenomenon and the advantages it affords remain poorly understood. Here we identify a microRNA family, miR-103/107, that attenuates miRNA biosynthesis by targeting Dicer, a key component of the miRNA processing machinery. In human breast cancer, high levels of miR-103/107 are associated with metastasis and poor outcome. Functionally, miR-103/107 confer migratory capacities in vitro and empower metastatic dissemination of otherwise nonaggressive cells in vivo. Inhibition of miR-103/107 opposes migration and metastasis of malignant cells. At the cellular level, a key event fostered by miR-103/107 is induction of epithelial-to-mesenchymal transition (EMT), attained by downregulating miR-200 levels. These findings suggest a new pathway by which Dicer inhibition drifts epithelial cancer toward a less-differentiated, mesenchymal fate to foster metastasis.


Assuntos
Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Metástase Neoplásica/genética , Ribonuclease III/genética , Animais , Neoplasias da Mama/diagnóstico , Linhagem Celular Tumoral , Movimento Celular , Regulação para Baixo , Feminino , Humanos , Camundongos , Prognóstico
4.
Cancer ; 130(13): 2272-2286, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38644692

RESUMO

BACKGROUND: Long-term daily use of aspirin reduces incidence and mortality due to colorectal cancer (CRC). This study aimed to analyze the effect of aspirin on the tumor microenvironment, systemic immunity, and on the healthy mucosa surrounding cancer. METHODS: Patients with a diagnosis of CRC operated on from 2015 to 2019 were retrospectively analyzed (METACCRE cohort). Expression of mRNA of immune surveillance-related genes (PD-L1, CD80, CD86, HLA I, and HLA II) in CRC primary cells treated with aspirin were extracted from Gene Expression Omnibus-deposited public database (GSE76583). The experiment was replicated in cell lines. The mucosal immune microenvironment of a subgroup of patients participating in the IMMUNOREACT1 (ClinicalTrials.gov NCT04915326) project was analyzed with immunohistochemistry and flow cytometry. RESULTS: In the METACCRE Cohort, 12% of 238 patients analyzed were aspirin users. Nodal metastasis was significantly less frequent (p = .008) and tumor-infiltrating lymphocyte infiltration was higher (p = .02) among aspirin users. In the CRC primary cells and selected cell lines, CD80 mRNA expression was increased following aspirin treatment (p = .001). In the healthy mucosa surrounding rectal cancer, the ratio of CD8/CD3 and epithelial cells expressing CD80 was higher in aspirin users (p = .027 and p = .034, respectively). CONCLUSIONS: These data suggested that regular aspirin use may have an active role in enhancing immunosurveillance against CRC.


Assuntos
Aspirina , Neoplasias Colorretais , Vigilância Imunológica , Linfócitos do Interstício Tumoral , Microambiente Tumoral , Humanos , Aspirina/uso terapêutico , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/genética , Feminino , Masculino , Microambiente Tumoral/imunologia , Idoso , Pessoa de Meia-Idade , Vigilância Imunológica/efeitos dos fármacos , Estudos Retrospectivos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Antígeno B7-1/metabolismo , Antígeno B7-1/genética , Antígeno B7-H1/metabolismo , Linhagem Celular Tumoral
5.
Cell ; 137(1): 87-98, 2009 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-19345189

RESUMO

TGFbeta ligands act as tumor suppressors in early stage tumors but are paradoxically diverted into potent prometastatic factors in advanced cancers. The molecular nature of this switch remains enigmatic. Here, we show that TGFbeta-dependent cell migration, invasion and metastasis are empowered by mutant-p53 and opposed by p63. Mechanistically, TGFbeta acts in concert with oncogenic Ras and mutant-p53 to induce the assembly of a mutant-p53/p63 protein complex in which Smads serve as essential platforms. Within this ternary complex, p63 functions are antagonized. Downstream of p63, we identified two candidate metastasis suppressor genes associated with metastasis risk in a large cohort of breast cancer patients. Thus, two common oncogenic lesions, mutant-p53 and Ras, selected in early neoplasms to promote growth and survival, also prefigure a cellular set-up with particular metastasis proclivity by TGFbeta-dependent inhibition of p63 function.


Assuntos
Metástase Neoplásica , Proteínas Smad/metabolismo , Transativadores/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Humanos , Camundongos , Mutação , Transplante de Neoplasias , Organismos Livres de Patógenos Específicos , Fatores de Transcrição , Proteína Supressora de Tumor p53/genética , Proteínas ras/metabolismo
6.
Br J Haematol ; 202(1): 147-152, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36916680

RESUMO

Accessory spleens (AcS) may play a relevant role in immune thrombocytopenia (ITP) and possibly contribute to ITP relapse following splenectomy. Little is known about the immune microenvironment of AcS in ITP. To address this issue, we compared the histological features of eight matched AcS and main spleen (MS) samples, obtained from adult patients with primary ITP. AcS and MS had overlapping immune architectural features and lymphoid composition, suggesting that similar immunologic events occur in AcS and MS of ITP. These findings may have implications for the potential mechanisms of AcS-mediated ITP relapse. Further studies are needed to confirm these results and to dissect spleen immunity in ITP.


Assuntos
Púrpura Trombocitopênica Idiopática , Esplenopatias , Trombocitopenia , Adulto , Humanos , Esplenectomia/métodos , Recidiva
7.
Br J Surg ; 110(11): 1490-1501, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37478362

RESUMO

BACKGROUND: Colon cancer in young patients is often associated with hereditary syndromes; however, in early-onset rectal cancer, mutations of these genes are rarely observed. The aim of this study was to analyse the features of the local immune microenvironment and the mutational pattern in early-onset rectal cancer. METHODS: Commonly mutated genes were analysed within a rectal cancer series from the University Hospital of Padova. Mutation frequency and immune gene expression in a cohort from The Cancer Genome Atlas ('TCGA') were compared and immune-cell infiltration levels in the healthy rectal mucosa adjacent to rectal cancers were evaluated in the IMMUNOlogical microenvironment in REctal AdenoCarcinoma Treatment 1 and 2 ('IMMUNOREACT') series. RESULTS: In the authors' series, the mutation frequency of BRAF, KRAS, and NRAS, as well as microsatellite instability frequency, were not different between early- and late-onset rectal cancer. In The Cancer Genome Atlas series, among the genes with the most considerable difference in mutation frequency between young and older patients, seven genes are involved in the immune response and CD69, CD3, and CD8ß expression was lower in early-onset rectal cancer. In the IMMUNOlogical microenvironment in REctal AdenoCarcinoma Treatment 1 and 2 series, young patients had a lower rate of CD4+ T cells, but higher T regulator infiltration in the rectal mucosa. CONCLUSION: Early-onset rectal cancer is rarely associated with common hereditary syndromes. The tumour microenvironment is characterized by a high frequency of mutations impairing the local immune surveillance mechanisms and low expression of immune editing-related genes. A constitutively low number of CD4 T cells associated with a high number of T regulators indicates an imbalance in the immune surveillance mechanisms.

8.
Br J Haematol ; 198(5): 916-922, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35701886

RESUMO

Thrombopoietin receptor agonists (TPO-RA) are a valid therapy for immune thrombocytopenia (ITP), due to megakaryocyte stimulation and (poorly characterised) immune-modulatory effects. The spleen is pivotal in the pathogenesis of ITP, yet little is known on its immune microenvironment and on effects of TPO-RA on this organ. To address these topics, we analysed 35 spleens removed for primary refractory ITP. Pre-splenectomy TPO-RA administration correlated with increased splenic regulatory T cells (Tregs), type 2 T-helper cells and histiocyte density and with reduced red pulp sinusoids. Surgical outcome was not associated with TPO-RA administration, other pre-splenectomy therapies and/or Treg density. In conclusion, TPO-RA affect the splenic microenvironment, but this has no impact on splenectomy outcome.


Assuntos
Púrpura Trombocitopênica Idiopática , Trombocitopenia , Humanos , Púrpura Trombocitopênica Idiopática/etiologia , Receptores Fc , Receptores de Trombopoetina/agonistas , Proteínas Recombinantes de Fusão , Baço/patologia , Linfócitos T Reguladores/patologia , Trombocitopenia/complicações , Trombopoetina/farmacologia , Trombopoetina/uso terapêutico
9.
Hepatology ; 72(3): 982-996, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31879968

RESUMO

BACKGROUND AND AIMS: Changes in single microRNA (miRNA) expression have been associated with chemo-resistance in biliary tract cancers (BTCs). However, a global assessment of the dynamic role of the microRNome has never been performed to identify potential therapeutic targets that are functionally relevant in the BTC cell response to chemotherapy. APPROACH AND RESULTS: High-throughput screening (HTS) of 997 locked nucleic acid miRNA inhibitors was performed in six cholangiocarcinoma cell lines treated with cisplatin and gemcitabine (CG) seeking changes in cell viability. Validation experiments were performed with mirVana probes. MicroRNA and gene expression was assessed by TaqMan assay, RNA-sequencing, and in situ hybridization in four independent cohorts of human BTCs. Knockout of microRNA was achieved by CRISPR-CAS9 in CCLP cells (MIR1249KO) and tested for effects on chemotherapy sensitivity in vitro and in vivo. HTS revealed that MIR1249 inhibition enhanced chemotherapy sensitivity across all cell lines. MIR1249 expression was increased in 41% of cases in human BTCs. In validation experiments, MIR1249 inhibition did not alter cell viability in untreated or dimethyl sulfoxide-treated cells; however, it did increase the CG effect. MIR1249 expression was increased in CD133+ biliary cancer cells freshly isolated from the stem cell niche of human BTCs as well as in CD133+ chemo-resistant CCLP cells. MIR1249 modulated the chemotherapy-induced enrichment of CD133+ cells by controlling their clonal expansion through the Wnt-regulator FZD8. MIR1249KO cells had impaired expansion of the CD133+ subclone and its enrichment after chemotherapy, reduced expression of cancer stem cell markers, and increased chemosensitivity. MIR1249KO xenograft BTC models showed tumor shrinkage after exposure to weekly CG, whereas wild-type models showed only stable disease over treatment. CONCLUSIONS: MIR1249 mediates resistance to CG in BTCs and may be tested as a target for therapeutics.


Assuntos
Neoplasias do Sistema Biliar , Colangiocarcinoma , Cisplatino/farmacologia , Desoxicitidina/análogos & derivados , MicroRNAs , Antineoplásicos/farmacologia , Neoplasias do Sistema Biliar/tratamento farmacológico , Neoplasias do Sistema Biliar/metabolismo , Neoplasias do Sistema Biliar/patologia , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/metabolismo , Colangiocarcinoma/patologia , Desoxicitidina/farmacologia , Descoberta de Drogas , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Ensaios de Triagem em Larga Escala/métodos , Humanos , MicroRNAs/antagonistas & inibidores , MicroRNAs/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
10.
Cancer Sci ; 110(5): 1552-1563, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30825353

RESUMO

Squamous cell carcinoma antigen-1 (SCCA1) overexpression is associated with poor prognosis and chemoresistance in several tumor types, however, the underlying mechanisms remain elusive. Here, we report SCCA1 in relation to the immune and peritumoral adipose tissue microenvironment in early and advanced esophageal adenocarcinoma (EAC). In our series of patients with EAC, free SCCA1 serum levels were associated with significantly worse overall survival, and SCCA1-IgM serum levels showed a trend to a worse overall survival. Serum SCCA1 and intratumoral SCCA1 were inversely correlated with immune activation markers. In agreement with these findings, SCCA1 induced the expression of the immune checkpoint molecule programmed death ligand-1 on monocytes and a direct correlation of these 2 molecules was observed in sequential tumor sections. Furthermore, SCCA1 mRNA expression within the tumor was inversely correlated with stem cell marker expression both within the tumor and in the peritumoral adipose tissue. In vitro, in EAC cell lines treated with different chemotherapeutic drugs, cell viability was significantly modified by SCCA1 presence, as cells overexpressing SCCA1 were significantly more resistant to cell death. In conclusion, poor prognosis in EAC overexpressing SCCA1 is due to reduced tumor chemosensitivity as well as intratumoral immunity impairment, likely induced by this molecule.


Assuntos
Adenocarcinoma/metabolismo , Antígenos de Neoplasias/sangue , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Resistencia a Medicamentos Antineoplásicos , Neoplasias Esofágicas/metabolismo , Serpinas/sangue , Adenocarcinoma/genética , Idoso , Antígenos de Neoplasias/genética , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular , Neoplasias Esofágicas/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Serpinas/genética , Análise de Sobrevida , Regulação para Cima
11.
Br J Cancer ; 121(3): 257-263, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31235864

RESUMO

BACKGROUND: Claudin-18 (CLDN18) is a highly specific tight junction protein of the gastric mucosa. An isoform of CLDN18, the Claudin 18.2, has recently emerged as an innovative drug target for metastatic gastric cancer. METHODS: We investigated the immunohistochemical profile of CLDN18, p53, p16, E-cadherin, MSH2, MSH6, MLH1, PSM2, HER2, and PDL-1 in a large series of 523 primary gastric carcinomas (GCs; n = 408) and gastro-oesophageal carcinomas (GECs; n = 115) and 135 matched and synchronous nodal metastases. The status of HER2 and EBER by means of chromogenic in situ hybridisation (CISH) was also evaluated. RESULTS: High membranous CLDN18 expression was present in 150/510 (29.4%) primary cases and in 45/132 (34.1%) metastases. An abnormal expression (i.e. nuclear and/or cytoplasmic) was observed in 115 (22.5%) primary cases and in 33 (25.0%) metastases. A 38.8% of the cases showed significant CLDN18 intratumoural variability among the different tissue microarray cores obtained from the same tumour. Positive membrane CLDN18 expression was statistically associated with non-antral GCs (p = 0.016), Lauren diffuse type (p = 0.009), and with EBV-associated cancers (p < 0.001). CONCLUSIONS: CLDN18 is frequently expressed in gastric and gastro-oesophageal cancers; further studies should investigate the prognostic significance of CLDN18 heterogeneity in order to implement its test into clinical practice.


Assuntos
Adenocarcinoma/química , Claudinas/análise , Neoplasias Gástricas/química , Análise Serial de Tecidos/métodos , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/análise , Neoplasias Gástricas/patologia
12.
Br J Cancer ; 121(7): 593-599, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31474758

RESUMO

BACKGROUND: V600EBRAF mutated metastatic colorectal cancer (mCRC) is a subtype (10%) with overall poor prognosis, but the clinical experience suggests a great heterogeneity in survival. It is still unexplored the real distribution of traditional and innovative biomarkers among V600EBRAF mutated mCRC and which is their role in the improvement of clinical prediction of survival outcomes. METHODS: Data and tissue specimens from 155 V600EBRAF mutated mCRC patients treated at eight Italian Units of Oncology were collected. Specimens were analysed by means of immunohistochemistry profiling performed on tissue microarrays. Primary endpoint was overall survival (OS). RESULTS: CDX2 loss conferred worse OS (HR = 1.72, 95%CI 1.03-2.86, p = 0.036), as well as high CK7 expression (HR = 2.17, 95%CI 1.10-4.29, p = 0.026). According to Consensus Molecular Subtypes (CMS), CMS1 patients had better OS compared to CMS2-3/CMS4 (HR = 0.37, 95%CI 0.19-0.71, p = 0.003). Samples showing less TILs had worse OS (HR = 1.72, 95%CI 1.16-2.56, p = 0.007). Progression-free survival analyses led to similar results. At multivariate analysis, CK7 and CMS subgrouping retained their significant correlation with OS. CONCLUSION: The present study provides new evidence on how several well-established biomarkers perform in a homogenousV600EBRAF mutated mCRC population, with important and independent information added to standard clinical prognosticators. These data could be useful to inform further translational research, for patients' stratification in clinical trials and in routine clinical practice to better estimate patients' prognosis.


Assuntos
Fator de Transcrição CDX2/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Queratina-7/metabolismo , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Biomarcadores Tumorais/metabolismo , Fator de Transcrição CDX2/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Proteínas do Citoesqueleto/metabolismo , Feminino , Deleção de Genes , Genes MCC , Humanos , Queratina-20/metabolismo , Linfócitos do Interstício Tumoral , Masculino , Pessoa de Meia-Idade , Proteína 2 Homóloga a MutS/metabolismo , Prognóstico , Análise Serial de Tecidos
13.
Gastroenterology ; 154(4): 1066-1079.e5, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29113809

RESUMO

BACKGROUND & AIMS: Cholangiocarcinomas (CCA) are resistant to chemotherapy, so new therapeutic agents are needed. We performed a screen to identify small-molecule compounds that are active against CCAs. Levels of microRNA 21 (MIR21 or miRNA21) are increased in CCAs. We investigated whether miRNA21 mediates resistance of CCA cells and organoids to HSP90 inhibitors. METHODS: We performed a high-throughput screen of 484 small-molecule compounds to identify those that reduced viability of 6 human CCA cell lines. We tested the effects of HSP90 inhibitors on cells with disruption of the MIR21 gene, cells incubated with MIR21 inhibitors, and stable cell lines with inducible expression of MIR21. We obtained CCA biopsies from patients, cultured them as organoids (patient-derived organoids). We assessed their architecture, mutation and gene expression patterns, response to compounds in culture, and when grown as subcutaneous xenograft tumors in mice. RESULTS: Cells with IDH1 and PBRM1 mutations had the highest level of sensitivity to histone deacetylase inhibitors. HSP90 inhibitors were effective in all cell lines, irrespective of mutations. Sensitivity of cells to HSP90 inhibitors correlated inversely with baseline level of MIR21. Disruption of MIR21 increased cell sensitivity to HSP90 inhibitors. CCA cells that expressed transgenic MIR21 were more resistant to HSP90 inhibitors than cells transfected with control vectors; inactivation of MIR21 in these cells restored sensitivity to these agents. MIR21 was shown to target the DnaJ heat shock protein family (Hsp40) member B5 (DNAJB5). Transgenic expression of DNAJB5 in CCA cells that overexpressed MIR21 re-sensitized them to HSP90 inhibitors. Sensitivity of patient-derived organoids to HSP90 inhibitors, in culture and when grown as xenograft tumors in mice, depended on expression of miRNA21. CONCLUSIONS: miRNA21 appears to mediate resistance of CCA cells to HSP90 inhibitors by reducing levels of DNAJB5. HSP90 inhibitors might be developed for the treatment of CCA and miRNA21 might be a marker of sensitivity to these agents.


Assuntos
Antineoplásicos/farmacologia , Neoplasias dos Ductos Biliares/tratamento farmacológico , Colangiocarcinoma/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , MicroRNAs/metabolismo , Animais , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/metabolismo , Neoplasias dos Ductos Biliares/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Colangiocarcinoma/genética , Colangiocarcinoma/metabolismo , Colangiocarcinoma/patologia , Proteínas de Ligação a DNA , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Choque Térmico HSP40/genética , Proteínas de Choque Térmico HSP40/metabolismo , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Isocitrato Desidrogenase/genética , Camundongos Endogâmicos NOD , Camundongos SCID , MicroRNAs/genética , Mutação , Proteínas Nucleares/genética , Organoides , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Fatores de Transcrição/genética , Transfecção , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Gut ; 66(7): 1268-1277, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27618837

RESUMO

OBJECTIVE: Transcribed-ultraconserved regions (T-UCR) are long non-coding RNAs which are conserved across species and are involved in carcinogenesis. We studied T-UCRs downstream of the Wnt/ß-catenin pathway in liver cancer. DESIGN: Hypomorphic Apc mice (Apcfl/fl) and thiocetamide (TAA)-treated rats developed Wnt/ß-catenin dependent hepatocarcinoma (HCC) and cholangiocarcinoma (CCA), respectively. T-UCR expression was assessed by microarray, real-time PCR and in situ hybridisation. RESULTS: Overexpression of the T-UCR uc.158- could differentiate Wnt/ß-catenin dependent HCC from normal liver and from ß-catenin negative diethylnitrosamine (DEN)-induced HCC. uc.158- was overexpressed in human HepG2 versus Huh7 cells in line with activation of the Wnt pathway. In vitro modulation of ß-catenin altered uc.158- expression in human malignant hepatocytes. uc.158- expression was increased in CTNNB1-mutated human HCCs compared with non-mutated human HCCs, and in human HCC with nuclear localisation of ß-catenin. uc.158- was increased in TAA rat CCA and reduced after treatment with Wnt/ß-catenin inhibitors. uc.158- expression was negative in human normal liver and biliary epithelia, while it was increased in human CCA in two different cohorts. Locked nucleic acid-mediated inhibition of uc.158- reduced anchorage cell growth, 3D-spheroid formation and spheroid-based cell migration, and increased apoptosis in HepG2 and SW1 cells. miR-193b was predicted to have binding sites within the uc.158- sequence. Modulation of uc.158- changed miR-193b expression in human malignant hepatocytes. Co-transfection of uc.158- inhibitor and anti-miR-193b rescued the effect of uc.158- inhibition on cell viability. CONCLUSIONS: We showed that uc.158- is activated by the Wnt pathway in liver cancers and drives their growth. Thus, it may represent a promising target for the development of novel therapeutics.


Assuntos
Neoplasias dos Ductos Biliares/metabolismo , Carcinoma Hepatocelular/metabolismo , Colangiocarcinoma/metabolismo , Sequência Conservada/genética , Neoplasias Hepáticas/metabolismo , RNA não Traduzido/genética , Via de Sinalização Wnt , Animais , Neoplasias dos Ductos Biliares/genética , Carcinoma Hepatocelular/genética , Colangiocarcinoma/genética , Regulação Neoplásica da Expressão Gênica/genética , Hepatócitos/metabolismo , Humanos , Neoplasias Hepáticas/genética , Camundongos Knockout , MicroRNAs/metabolismo , Neoplasias Experimentais , Transfecção , beta Catenina/genética , beta Catenina/metabolismo
15.
Br J Haematol ; 178(1): 81-93, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28419476

RESUMO

Cortactin (CTTN) is a substrate of the Src kinase Lyn that is known to play an actin cytoskeletal regulatory role involved in cell migration and cancer progression following its phosphorylation at Y421. We recently demonstrated that Cortactin is overexpressed in patients with chronic lymphocytic leukaemia (CLL). This work was aimed at defining the functional role of Cortactin in these patients. We found that Cortactin is variably expressed in CLL patients both in the peripheral blood and lymph nodes and that its expression correlates with the release of matrix metalloproteinase 9 (MMP-9) and the motility of neoplastic cells. Cortactin knockdown, by siRNA, induced a reduction in MMP-9 release as well as a decrease of migration capability of leukaemic B cells in vitro, also after chemotactic stimulus. Furthermore, Cortactin phosphorylation was lowered by the Src kinase-inhibitor PP2 with a consequent decrease of MMP-9 release in culture medium. An impaired migration, as compared to control experiments without Cortactin knockdown, was observed following CXCL12 triggering. Reduced Cortactin expression and phosphorylation were also detected both in vivo and in vitro after treatment with Ibrutinib, a Btk inhibitor. Our results highlight the role of Cortactin in CLL as a check-point molecule between the BCR and CXCR4 signalling pathways.


Assuntos
Pontos de Checagem do Ciclo Celular/fisiologia , Cortactina/fisiologia , Leucemia Linfocítica Crônica de Células B/metabolismo , Proteínas Proto-Oncogênicas c-bcr/fisiologia , Receptores CXCR4/fisiologia , Adenina/análogos & derivados , Adulto , Tirosina Quinase da Agamaglobulinemia , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Movimento Celular/fisiologia , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Pessoa de Meia-Idade , Proteínas de Neoplasias/fisiologia , Fosforilação/efeitos dos fármacos , Piperidinas , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirazóis/farmacologia , Pirazóis/uso terapêutico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Transdução de Sinais/fisiologia , Células Tumorais Cultivadas , Quinases da Família src/fisiologia
16.
Histopathology ; 71(3): 470-474, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28502094

RESUMO

AIMS: PD-1/PD-L1 checkpoint immunotherapy has been proposed recently as a promising treatment in relapsed/refractory disease, used eventually in combination with traditional chemotherapy in different cancer settings. To date, no data are available concerning PD-L1 expression in ampulla of Vater carcinoma and its pre-invasive lesions. METHODS AND RESULTS: We assessed the immunohistochemical expression of PD-L1 in a series of 26 ampullary adenocarcinomas, 50 ampullary dysplastic lesions and 10 normal duodenal mucosa samples. Moreover, in all cases DNA mismatch repair proteins status was investigated. PD-L1 was expressed in seven of 26 (26.9%) invasive carcinomas and three of 50 (6.0%) dysplastic samples. Most of the PD-L1-positive tumours (seven of 10) were intestinal-type and poorly differentiated (G3). The number of PD-L1-positive stromal lymphoid cells was significantly higher in dysplastic and invasive lesions than in the normal samples (P = 0.011). Nineteen dysplastic lesions and eight invasive carcinomas did not show any evident epithelial or stromal PD-L1 expression. Four of the carcinomas were mismatch repair-deficient and two of these were PD-L1-positive. Furthermore, mismatch repair-deficient lesions showed a significantly higher average of PD-L1-positive stromal lymphoid cells than those of neoplastic PD-L1-negative samples (62.8 versus 21.6; P < 0.001). CONCLUSIONS: The present results suggest a role of the PD-1/PD-L1 axis in ampullary adenocarcinomas, and therefore this may also prompt consideration of checkpoint immunotherapy as a novel promising treatment for these tumours.


Assuntos
Adenocarcinoma/patologia , Ampola Hepatopancreática/patologia , Antígeno B7-H1/biossíntese , Biomarcadores Tumorais/análise , Adenocarcinoma/imunologia , Adulto , Idoso , Ampola Hepatopancreática/imunologia , Antígeno B7-H1/análise , Biomarcadores Tumorais/imunologia , Carcinoma Ductal Pancreático/imunologia , Carcinoma Ductal Pancreático/patologia , Neoplasias do Ducto Colédoco/imunologia , Neoplasias do Ducto Colédoco/patologia , Neoplasias Duodenais/imunologia , Neoplasias Duodenais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/imunologia , Lesões Pré-Cancerosas/patologia
17.
J Pediatr Gastroenterol Nutr ; 62(5): 692-7, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26513623

RESUMO

OBJECTIVES: Hirschsprung's disease (HSCR) results from a malformation of the enteric nervous system. A congenital absence of intrinsic ganglion cells from the distal rectum and a variable length of the contiguous bowel is the required diagnostic feature of Hirschsprung's disease and total colonic aganglionosis (TCA). We evaluated the utility of a monoclonal antibody directed against glypican 3 (GPC-3), a membrane bound protein involved in regulation of the signaling of Wingless-types (WNTs), Hedgehogs (Hh), Fibroblast Growth Factors (FGFs), and Bone Morphogenetic Proteins (BMPs), in the detection of ganglion cells in formalin-fixed, paraffin-embedded tissue sections. METHODS: The presence/absence of ganglion cells was evaluated retrospectively by immunohistochemical staining for calretinin and GPC-3 in tissue specimens; a total of 15 patients who underwent colectomy (total or sub-total) for histologically proven aganglionosis (14 HSCR, 1 TCA) and 5 rectal suction biopsies (4HSCR-B, 1 TCA-B) were considered. Of the 20 considered cases, a total of 60 tissue specimens (3 for each patient) were selected. A total of 30 additional normal (N) colonic mucosa biopsy samples were also included. RESULTS: GPC-3 constantly identified ganglion cell bodies in all but 2 normal biopsies (with normal presentation of ganglion cells on hematoxylin and eosin (H&E) stain), and was negative in all 60 aganglionotic biopsies; these results were reflective of calretinin staining pattern. CONCLUSIONS: The present study indicates that monoclonal anti-GPC-3 might prove to be useful immunohistochemical marker in the identification of ganglion cells in paraffin-embedded rectal tissue specimens and suction biopsies. Further studies in larger series will contribute to demonstrate its utility as an ancillary marker in the histological assessment of HSCR aganglionosis.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Calbindina 2/metabolismo , Glipicanas/antagonistas & inibidores , Doença de Hirschsprung/patologia , Biomarcadores/metabolismo , Biópsia , Estudos de Casos e Controles , Feminino , Glipicanas/imunologia , Humanos , Lactente , Recém-Nascido , Masculino , Valor Preditivo dos Testes , Reto/patologia , Estudos Retrospectivos
18.
Am J Pathol ; 184(12): 3376-83, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25455689

RESUMO

Penile squamous cell carcinoma (PSCC) is a rare tumor associated with high-risk human papillomavirus (HR-HPV) infection in 30% to 60% of cases. Altered expression of miRNAs has been reported in HPV-related cervical and head and neck cancers, but such data have not been available for PSCC. We analyzed a series of 59 PSCCs and 8 condylomata for presence of HPV infection, for p16(INK4a), Ki-67, and p53 immunohistochemical expression, and for expression of a panel of cellular miRNAs (let-7c, miR-23b, miR-34a, miR-145, miR-146a, miR-196a, and miR-218) involved in HPV-related cancer. HR-HPV DNA (HPV16 in most cases) was detected in 17/59 (29%) PSCCs; all penile condylomata (8/8) were positive for low-risk HPV6 or HPV11. HR-HPV(+) PSCCs overexpressed p16(INK4a) in 88% cases and p53 in 35% of cases, whereas HR-HPV(-) PSCCs were positive for p16(INK4a) and p53 immunostaining in 9% and 44% of cases, respectively. Among the miRNAs investigated, expression of miR-218 was lower in PSCCs with HR-HPV infection and in p53(-) cancers. Hypermethylation of the promoter of the SLIT2 gene, which contains miR-218-1 in its intronic region, was frequently observed in PSCCs, mainly in those with low miR-218 expression. Epigenetic silencing of miR-218 is a common feature in HR-HPV(+) PSCCs and in HR-HPV(-) PSCCs without immunohistochemical detection of p53.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/virologia , Perfilação da Expressão Gênica , MicroRNAs/metabolismo , Neoplasias Penianas/metabolismo , Neoplasias Penianas/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/complicações , Metilação de DNA , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intercelular/genética , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/genética , Papillomaviridae , Infecções por Papillomavirus/complicações , Neoplasias Penianas/complicações
19.
Histopathology ; 67(4): 491-500, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25684546

RESUMO

AIMS: Laryngeal squamous cell carcinoma (LSCC) prognosis is definitely related to lymph node metastasis. Epithelial-mesenchymal transition (EMT) allows neoplastic cells to gain the plasticity and motility required for tumour progression and metastasis. The aim of this study was to investigate the role of EMT in the prognosis of LSCC. METHODS AND RESULTS: Immunohistochemical analysis of E-cadherin, N-cadherin, Snail, Slug, ZEB1, and ZEB2 was performed in 37 consecutive LSCC cases. Low E-cadherin levels and high Slug levels correlated with both disease recurrence (P = 0.02 and P =0.01, respectively) and shorter disease-free survival (DFS) (P = 0.04 and P = 0.02, respectively). Relative expression levels of CDH1, SNAI2, miR-1 and the miR-200 family were also evaluated. CDH1, miR-200a and miR-200c down-regulation and SNAI2 overexpression were significantly associated with disease recurrence (P = 0.03, P = 0.02, P = 0.04, and P = 0.04, respectively). CONCLUSIONS: EMT increases tumour recurrence risk and shortens DFS in LSCC. E-cadherin and Slug immunohistochemical analysis could be useful for identifying patients requiring more aggressive treatment after surgery.


Assuntos
Biomarcadores Tumorais/análise , Caderinas/biossíntese , Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias Laríngeas/patologia , Fatores de Transcrição/biossíntese , Idoso , Caderinas/análise , Carcinoma de Células Escamosas/mortalidade , Intervalo Livre de Doença , Transição Epitelial-Mesenquimal , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Imuno-Histoquímica , Neoplasias Laríngeas/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Prognóstico , Modelos de Riscos Proporcionais , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição da Família Snail , Carcinoma de Células Escamosas de Cabeça e Pescoço , Fatores de Transcrição/análise
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