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1.
Am J Clin Pathol ; 161(2): 170-176, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37904278

RESUMO

OBJECTIVES: Determination of bone marrow cellularity is a key part of bone marrow examination because it provides a small window into a patient's current state of hematopoietic well-being. Traditionally, bone marrow cellularity is estimated semiquantitatively through microscopic examination of core biopsy specimens harvested from the iliac crest of the pelvic bone. Bone marrow cellularity is then designated as hypercellular, normocellular, or hypocellular based on the patient's age. This assessment can have significant clinical impact, but the variation in the age-adjusted normocellularity range is not sufficiently characterized because of a lack of study data, especially in older patients (those older than 70 years of age). This study further established the normal range of bone marrow cellularity, particularly in older adults. METHODS: In this study, 570 benign staging and healthy donor bone marrows from patients 1 year to 93 years of age were analyzed for cellularity. RESULTS: Linear regression modeling demonstrates that cellularity in adults declines approximately 3% per decade, including after the seventh decade of life. The 90% reference interval for normocellularity in United States is 30% to 75% for those aged 18 to 90 years. CONCLUSIONS: The findings revealed a more stable and slower rate of decline in cellularity with age in adults than the widely used linear model of "100% minus the patient age in decades." Normocellularity is better modeled based on age group. In those younger than 20 years of age, normocellularity ranges from 45% to 85% (mean [SD], 65% [20%]), as defined by Friebert et al in 1998. Based on our study finding of a little less than 3% decline per decade of age, the following is our recommendation for normocellularity range: For individuals 20 to 40 years of age, it ranges from 40% to 70% (mean [SD], 55% [15%]); for individuals 40 to 60 years of age, it ranges from 35% to 65% (mean [SD], 50% [15%]); and for individuals older than 60 years of age, it ranges from 30% to 60% (mean [SD], 45% [15%]). Interestingly, those older than 70 years of age do not show a significant decrease from those aged 60 to 69 years.


Assuntos
Células da Medula Óssea , Medula Óssea , Humanos , Idoso , Adulto Jovem , Adulto , Lactente , Medula Óssea/patologia , Exame de Medula Óssea , Células da Medula Óssea/patologia , Biópsia com Agulha de Grande Calibre , Hiperplasia/patologia
2.
Blood Adv ; 7(7): 1146-1155, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-36375132

RESUMO

The CORAL study highlighted the need to develop novel salvage regimens in relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL) previously treated with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone. Carfilzomib (CFZ) can overcome rituximab chemotherapy resistance in lymphoma preclinical models by targeting the ubiquitin-proteasome system. We conducted an investigator initiated, single-center, open-label, prospective phase 1 study evaluating the safety and efficacy of CFZ in combination with rituximab, ifosfamide, carboplatin, and etoposide (C-R-ICE) in high-dose chemotherapy with autologous stem cell transplant (HDC-ASCT) eligible patients with R/R DLBCL (NCT01959698). In the dose-escalation phase, 18 patients were enrolled at 6 dose levels with no dose-limiting toxicities noted. CFZ 45 mg/m2 was selected as the recommended dose for expansion. Eleven additional patients were enrolled in the dose-expansion phase. Overall response rate (ORR) was 66% (48% CR; 17% PR); 52% patients underwent HDC-ASCT. An ORR of 85% was observed in patients with nongerminal center B-cell-like (non-GCB) DLBCL compared with only 13% in those with GCB DLBCL. Median progression-free survival (PFS) was 15.2 months (5.1 months, not reached [NR]), and median overall survival (OS) was 22.6 months (6.8 months, NR). Patients with non-GCB subtype had a significantly longer PFS (NR vs 6.6 months; P = .0001) and OS (NR vs 6.6 months; P = .001) than those with GCB subtype. C-R-ICE is well tolerated in patients with R/R DLBCL with toxicities comparable to rituximab, ifosfamide, carboplatin, and etoposide therapy. Our data show that patients with non-GCB DLBCL benefit significantly from incorporating CFZ into second-line therapy and HDC-ASCT.


Assuntos
Ifosfamida , Linfoma Difuso de Grandes Células B , Humanos , Rituximab , Ifosfamida/uso terapêutico , Carboplatina/uso terapêutico , Etoposídeo/efeitos adversos , Estudos Prospectivos , Anticorpos Monoclonais Murinos , Linfoma Difuso de Grandes Células B/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
3.
Hum Pathol ; 114: 19-27, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33964277

RESUMO

MYC rearrangement is a relatively rare genetic abnormality in follicular lymphoma (FL). In this study, we evaluated the relative frequency of MYC rearrangement in 522 cases of FL and studied their clinicopathologic, cytogenetic, and molecular characteristics. Fluorescence in situ hybridization studies for MYC (break-apart probe), MYC/IGH, IGH/BCL2, and BCL6 rearrangements were performed on tissue microarrays. Immunohistochemical stains for CD10, BCL2, BCL6, and MYC were performed and scored on MYC-rearranged cases. On 4 FL cases, a custom targeted panel of 356 genes was used for mutation analysis. Ten cases (1.9%) were positive for MYC rearrangement. Histologically, 6 of 10 cases were grade 1-2, and 4 cases were grade 3A. By immunohistochemistry, 9 of 9 tested cases were CD10+, all cases were BCL6+, and 9/10 cases were BCL2+. MYC protein staining was low in all cases tested. IGH/BCL2 rearrangement was detected in 5 of 9 cases, whereas BCL6 rearrangement was detected in 3 of 7 tested cases and 4 of 10 cases showed MYC/IGH rearrangement. The most commonly detected mutations in the MYC-positive cases included HLA-B, TNFRSF14, and KMT2D. MYC and/or B2M abnormalities were detected in 2 cases. In conclusion, MYC rearrangement is uncommon in FL and these cases do not appear to have specific histologic characteristics. Molecular analysis showed abnormalities in genes associated with transformation, namely MYC and B2M. Larger studies are needed to evaluate if MYC-rearrangement in FL has prognostic significance.


Assuntos
Biomarcadores Tumorais/genética , Rearranjo Gênico , Linfoma Folicular/genética , Proteínas Proto-Oncogênicas c-myc/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Análise Mutacional de DNA , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Linfoma Folicular/química , Linfoma Folicular/tratamento farmacológico , Linfoma Folicular/patologia , Masculino , Manitoba , Pessoa de Meia-Idade , Mutação , Prognóstico , Proteínas Proto-Oncogênicas c-myc/análise , Análise Serial de Tecidos , Estados Unidos
4.
BMC Health Serv Res ; 21(1): 379, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33892705

RESUMO

BACKGROUND: This study aimed to evaluate the cost-effectiveness of a breast cancer screening programme that incorporates genetic testing using breast cancer associated single nucleotide polymorphisms (SNPs), against the current biennial mammogram-only screening programme to aid in its implementation into the current programme in Singapore. METHODS: A Markov model was used to compare the costs and health outcomes of the current screening programme, against a polygenic risk-tailored screening programme, which can advise a long-term screening strategy depending on the individual's polygenic risk. The model took the perspective of the healthcare system, with a time horizon of 40 years, following women from the age of 35 to 74. Epidemiological and cost data were taken from Asian studies, and an annual discount rate of 3% was used. The model outcome was the incremental cost-effectiveness ratio (ICER), calculated from the difference in costs per quality-adjusted life year (QALY). Scenarios with varying risk thresholds for each polygenic risk group were examined. One-way and probabilistic sensitivity analyses were performed to assess parameter uncertainty. RESULTS: The ICER for a polygenic risk-tailored breast cancer screening programme, compared with the current biennial mammogram-only screening programme, was - 3713.80 SGD/QALY, with incremental costs < 0 and incremental effects > 0. The scenario analysis of different polygenic risk cutoffs showed that the ICERs remain negative, with all ICERs falling within the south-east quadrant of the cost-effectiveness plane, indicating that tailored screening is more cost effective than mammogram-only screening, with lower costs and higher QALYs to be gained. This suggests that a polygenic risk-tailored breast cancer screening programme is cost effective, entailing lower cost than the current mammogram-only programme, while causing no additional harm to women. CONCLUSION: Results from this cost-effectiveness analysis show that polygenic risk-tailored screening is cost effective with an ICER of - 3713.80 SGD/QALY. Tailored screening remains cost effective even across varying percentile cutoffs for each risk group. While the results look promising for incorporating polygenic risk into the current breast cancer screening programme, further studies should be conducted to address various limitations.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Análise Custo-Benefício , Detecção Precoce de Câncer , Feminino , Humanos , Mamografia , Anos de Vida Ajustados por Qualidade de Vida , Singapura/epidemiologia
5.
Cancer Immunol Res ; 8(6): 819-828, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32238380

RESUMO

Myeloid derived suppressor cells (MDSC) are a heterogeneous group of immature cells that accumulate in the peripheral blood and tumor microenvironment and are barriers to cancer therapy. MDSCs serve as prognostic biomarkers and are targets for therapy. On the basis of surface markers, three subsets of MDSCs have been defined in humans: granulocytic, monocytic, and early stage (e-MDSC). The markers attributed to e-MDSCs overlap with those of basophils, which are rare circulating myeloid cells with unrecognized roles in cancer. Thus, we asked whether e-MDSCs in circulation and the tumor microenvironment include basophils. On average, 58% of cells with e-MDSC surface markers in blood and 36% in ascites from patients with ovarian cancer were basophils based on CD123high expression and cytology, whereas cells with immature features were rare. Circulating and ascites basophils did not suppress proliferation of stimulated T cells, a key feature of MDSCs. Increased accumulation of basophils and basogranulin, a marker of basophil degranulation, were observed in ascites compared to serum in patients with newly diagnosed ovarian cancer. Basophils recruited to the tumor microenvironment may exacerbate fluid accumulation by their release of proinflammatory granular constituents that promote vascular leakage. No significant correlation was observed between peripheral basophil counts and survival in patients with ovarian cancer. Our results suggest that studies in which e-MDSCs were defined solely by surface markers should be reevaluated to exclude basophils. Both immaturity and suppression are criteria to define e-MDSCs in future studies.


Assuntos
Ascite/patologia , Basófilos/patologia , Biomarcadores Tumorais/sangue , Leucócitos Mononucleares/patologia , Células Supressoras Mieloides/patologia , Neoplasias Ovarianas/patologia , Microambiente Tumoral , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/cirurgia , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Taxa de Sobrevida , Células Tumorais Cultivadas
7.
Cell Mol Gastroenterol Hepatol ; 9(2): 295-312, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31606566

RESUMO

BACKGROUND AND AIMS: Tumor necrosis factor (TNF) is a major pathogenic effector and a therapeutic target in inflammatory bowel disease (IBD), yet the basis for TNF-induced intestinal epithelial cell (IEC) death is unknown, because TNF does not kill normal IECs. Here, we investigated how chronic nuclear factor (NF)- κB activation, which occurs in human IBD, promotes TNF-dependent IEC death in mice. METHODS: Human IBD specimens were stained for p65 and cleaved caspase-3. C57BL/6 mice with constitutively active IKKß in IEC (Ikkß(EE)IEC), Ripk1D138N/D138N knockin mice, and Ripk3-/- mice were injected with TNF or lipopolysaccharide. Enteroids were also isolated from these mice and challenged with TNF with or without RIPK1 and RIPK3 inhibitors or butylated hydroxyanisole. Ripoptosome-mediated caspase-8 activation was assessed by immunoprecipitation. RESULTS: NF-κB activation in human IBD correlated with appearance of cleaved caspase-3. Congruently, unlike normal mouse IECs that are TNF-resistant, IECs in Ikkß(EE)IEC mice and enteroids were susceptible to TNF-dependent apoptosis, which depended on the protein kinase function of RIPK1. Constitutively active IKKß facilitated ripoptosome formation, a RIPK1 signaling complex that mediates caspase-8 activation by TNF. Butylated hydroxyanisole treatment and RIPK1 inhibitors attenuated TNF-induced and ripoptosome-mediated caspase-8 activation and IEC death in vitro and in vivo. CONCLUSIONS: Contrary to common expectations, chronic NF-κB activation induced intestinal crypt apoptosis after TNF stimulation, resulting in severe mucosal erosion. RIPK1 kinase inhibitors selectively inhibited TNF destructive properties while preserving its survival and proliferative properties, which do not require RIPK1 kinase activity. RIPK1 kinase inhibition could be a potential treatment for IBD.


Assuntos
Apoptose/imunologia , Colite Ulcerativa/imunologia , Doença de Crohn/imunologia , Mucosa Intestinal/patologia , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Fator de Transcrição RelA/metabolismo , Adulto , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Células Cultivadas , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/patologia , Colo/efeitos dos fármacos , Colo/imunologia , Colo/patologia , Colonoscopia , Doença de Crohn/tratamento farmacológico , Doença de Crohn/patologia , Modelos Animais de Doenças , Células Epiteliais/imunologia , Células Epiteliais/patologia , Técnicas de Introdução de Genes , Humanos , Quinase I-kappa B/genética , Quinase I-kappa B/metabolismo , Íleo/imunologia , Íleo/patologia , Imidazóis/farmacologia , Imidazóis/uso terapêutico , Indóis/farmacologia , Indóis/uso terapêutico , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Camundongos Knockout , Organoides , Cultura Primária de Células , RNA-Seq , Proteína Serina-Treonina Quinases de Interação com Receptores/antagonistas & inibidores , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Fator de Necrose Tumoral alfa/metabolismo
8.
JCI Insight ; 4(5)2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30730851

RESUMO

Epithelial ovarian cancer (EOC) often presents with metastases and ascites. Granulocytic myeloid-derived suppressor cells are an immature population that impairs antitumor immunity. Since suppressive granulocytes in the ascites of patients with newly diagnosed EOC were morphologically mature, we hypothesized that PMN were rendered suppressive in the tumor microenvironment (TME). Circulating PMN from patients were not suppressive but acquired a suppressor phenotype (defined as ≥1 log10 reduction of anti-CD3/CD28-stimulated T cell proliferation) after ascites supernatant exposure. Ascites supernatants (20 of 31 supernatants) recapitulated the suppressor phenotype in PMN from healthy donors. T cell proliferation was restored with ascites removal and restimulation. PMN suppressors also inhibited T cell activation and cytokine production. PMN suppressors completely suppressed proliferation in naive, central memory, and effector memory T cells and in engineered tumor antigen-specific cytotoxic T lymphocytes, while antigen-specific cell lysis was unaffected. Inhibition of complement C3 activation and PMN effector functions, including CR3 signaling, protein synthesis, and vesicular trafficking, abrogated the PMN suppressor phenotype. Moreover, malignant effusions from patients with various metastatic cancers also induced the C3-dependent PMN suppressor phenotype. These results point to PMN impairing T cell expansion and activation in the TME and the potential for complement inhibition to abrogate this barrier to antitumor immunity.


Assuntos
Imunidade , Neutrófilos/imunologia , Neoplasias Ovarianas/imunologia , Linfócitos T/imunologia , Microambiente Tumoral/imunologia , Idoso , Antígenos CD28 , Proliferação de Células , Complemento C3 , Citocinas , Feminino , Granulócitos , Humanos , Ativação Linfocitária/imunologia , Muromonab-CD3 , Células Supressoras Mieloides/imunologia , Neoplasias Ovarianas/patologia
9.
Cancer Treat Res ; 176: 1-29, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30596211

RESUMO

PURPOSE: This review will describe and update readers on the recent changes in the 2017 WHO classification regarding peripheral T-cell lymphomas. RECENT FINDINGS: Signficant advances in molecular studies have resulted in revisions to the classification as well as introduction to provisional entities such as breast implant-associated ALCL and nodal PTCL with T-follicular helper phenotype. SUMMARY: Major advances in molecular and gene expression profiling has expanded our knowledge of these rare and aggressive diseases.


Assuntos
Células Matadoras Naturais , Linfoma de Células T Periférico , Perfilação da Expressão Gênica , Humanos , Linfoma de Células T Periférico/epidemiologia , Linfoma de Células T Periférico/imunologia , Linfoma de Células T Periférico/patologia
11.
Proc Natl Acad Sci U S A ; 115(39): E9192-E9200, 2018 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-30209212

RESUMO

Intestinal epithelial cell (IEC) death is a common feature of inflammatory bowel disease (IBD) that triggers inflammation by compromising barrier integrity. In many patients with IBD, epithelial damage and inflammation are TNF-dependent. Elevated TNF production in IBD is accompanied by increased expression of the TNFAIP3 gene, which encodes A20, a negative feedback regulator of NF-κB. A20 in intestinal epithelium from patients with IBD coincided with the presence of cleaved caspase-3, and A20 transgenic (Tg) mice, in which A20 is expressed from an IEC-specific promoter, were highly susceptible to TNF-induced IEC death, intestinal damage, and shock. A20-expressing intestinal organoids were also susceptible to TNF-induced death, demonstrating that enhanced TNF-induced apoptosis was a cell-autonomous property of A20. This effect was dependent on Receptor Interacting Protein Kinase 1 (RIPK1) activity, and A20 was found to associate with the Ripoptosome complex, potentiating its ability to activate caspase-8. A20-potentiated RIPK1-dependent apoptosis did not require the A20 deubiquitinase (DUB) domain and zinc finger 4 (ZnF4), which mediate NF-κB inhibition in fibroblasts, but was strictly dependent on ZnF7 and A20 dimerization. We suggest that A20 dimers bind linear ubiquitin to stabilize the Ripoptosome and potentiate its apoptosis-inducing activity.


Assuntos
Apoptose , Doenças Inflamatórias Intestinais/metabolismo , Mucosa Intestinal/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Caspase 3/genética , Caspase 3/metabolismo , Caspase 8/genética , Caspase 8/metabolismo , Humanos , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/patologia , Camundongos , Camundongos Transgênicos , NF-kappa B/genética , NF-kappa B/metabolismo , Multimerização Proteica , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/genética
12.
Nature ; 560(7717): 198-203, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30046112

RESUMO

Dysregulated NLRP3 inflammasome activity results in uncontrolled inflammation, which underlies many chronic diseases. Although mitochondrial damage is needed for the assembly and activation of the NLRP3 inflammasome, it is unclear how macrophages are able to respond to structurally diverse inflammasome-activating stimuli. Here we show that the synthesis of mitochondrial DNA (mtDNA), induced after the engagement of Toll-like receptors, is crucial for NLRP3 signalling. Toll-like receptors signal via the MyD88 and TRIF adaptors to trigger IRF1-dependent transcription of CMPK2, a rate-limiting enzyme that supplies deoxyribonucleotides for mtDNA synthesis. CMPK2-dependent mtDNA synthesis is necessary for the production of oxidized mtDNA fragments after exposure to NLRP3 activators. Cytosolic oxidized mtDNA associates with the NLRP3 inflammasome complex and is required for its activation. The dependence on CMPK2 catalytic activity provides opportunities for more effective control of NLRP3 inflammasome-associated diseases.


Assuntos
DNA Mitocondrial/biossíntese , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Animais , Biocatálise , Citosol/metabolismo , Fator Regulador 1 de Interferon/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Camundongos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Núcleosídeo-Fosfato Quinase/genética , Núcleosídeo-Fosfato Quinase/metabolismo , Oxirredução , Transdução de Sinais , Receptores Toll-Like/imunologia
13.
Cell Death Differ ; 24(5): 929-943, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28387757

RESUMO

Inflammation is frequently associated with initiation, progression, and metastasis of colorectal cancer (CRC). Here, we unveil a CRC-specific metastatic programme that is triggered via the transcriptional repressor, GFI1. Using data from a large cohort of clinical samples including inflammatory bowel disease and CRC, and a cellular model of CRC progression mediated by cross-talk between the cancer cell and the inflammatory microenvironment, we identified GFI1 as a gating regulator responsible for a constitutively activated signalling circuit that renders CRC cells competent for metastatic spread. Further analysis of mouse models with metastatic CRC and human clinical specimens reinforced the influence of GFI1 downregulation in promoting CRC metastatic spread. The novel role of GFI1 is uncovered for the first time in a human solid tumour such as CRC. Our results imply that GFI1 is a potential therapeutic target for interfering with inflammation-induced CRC progression and spread.


Assuntos
Neoplasias Colorretais/genética , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica , Doenças Inflamatórias Intestinais/genética , Neoplasias Hepáticas/genética , Fatores de Transcrição/genética , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/metabolismo , Progressão da Doença , Perfilação da Expressão Gênica , Células HT29 , Humanos , Inflamação , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundário , Metástase Linfática , Camundongos , Camundongos Nus , Invasividade Neoplásica , Transplante de Neoplasias , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Receptores de Prostaglandina E Subtipo EP2/genética , Receptores de Prostaglandina E Subtipo EP2/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Microambiente Tumoral/genética
14.
Cell ; 164(5): 896-910, 2016 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-26919428

RESUMO

Nuclear factor κB (NF-κB), a key activator of inflammation, primes the NLRP3-inflammasome for activation by inducing pro-IL-1ß and NLRP3 expression. NF-κB, however, also prevents excessive inflammation and restrains NLRP3-inflammasome activation through a poorly defined mechanism. We now show that NF-κB exerts its anti-inflammatory activity by inducing delayed accumulation of the autophagy receptor p62/SQSTM1. External NLRP3-activating stimuli trigger a form of mitochondrial (mt) damage that is caspase-1- and NLRP3-independent and causes release of direct NLRP3-inflammasome activators, including mtDNA and mtROS. Damaged mitochondria undergo Parkin-dependent ubiquitin conjugation and are specifically recognized by p62, which induces their mitophagic clearance. Macrophage-specific p62 ablation causes pronounced accumulation of damaged mitochondria and excessive IL-1ß-dependent inflammation, enhancing macrophage death. Therefore, the "NF-κB-p62-mitophagy" pathway is a macrophage-intrinsic regulatory loop through which NF-κB restrains its own inflammation-promoting activity and orchestrates a self-limiting host response that maintains homeostasis and favors tissue repair.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Choque Térmico/metabolismo , Inflamassomos/metabolismo , Mitocôndrias/metabolismo , Subunidade p50 de NF-kappa B/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Proteínas de Choque Térmico/genética , Interleucina-1beta/metabolismo , Lipopolissacarídeos/metabolismo , Macrófagos/metabolismo , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Proteína Sequestossoma-1 , Ubiquitina-Proteína Ligases/metabolismo
15.
Immunity ; 41(6): 1052-63, 2014 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-25526314

RESUMO

Interleukin-17A (IL-17A) is a pro-inflammatory cytokine linked to rapid malignant progression of colorectal cancer (CRC) and therapy resistance. IL-17A exerts its pro-tumorigenic activity through its type A receptor (IL-17RA). However, IL-17RA is expressed in many cell types, including hematopoietic, fibroblastoid, and epithelial cells, in the tumor microenvironment, and how IL-17RA engagement promotes colonic tumorigenesis is unknown. Here we show that IL-17RA signals directly within transformed colonic epithelial cells (enterocytes) to promote early tumor development. IL-17RA engagement activates ERK, p38 MAPK, and NF-κB signaling and promotes the proliferation of tumorigenic enterocytes that just lost expression of the APC tumor suppressor. Although IL-17RA signaling also controls the production of IL-6, this mechanism makes only a partial contribution to colonic tumorigenesis. Combined treatment with chemotherapy, which induces IL-17A expression, and an IL-17A neutralizing antibody enhanced the therapeutic responsiveness of established colon tumors. These findings establish IL-17A and IL-17RA as therapeutic targets in colorectal cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Colo/imunologia , Neoplasias Colorretais/imunologia , Enterócitos/fisiologia , Receptores de Interleucina-17/metabolismo , Focos de Criptas Aberrantes/genética , Animais , Anticorpos Bloqueadores/administração & dosagem , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Linhagem Celular Transformada , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/tratamento farmacológico , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/tratamento farmacológico , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Enterócitos/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fluoruracila/administração & dosagem , Humanos , Interleucina-17/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , NF-kappa B/metabolismo , Receptores de Interleucina-17/genética , Receptores de Interleucina-17/imunologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Tamoxifeno/administração & dosagem , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
16.
BMC Pulm Med ; 14: 187, 2014 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-25432663

RESUMO

BACKGROUND: Increased small airway resistance and decreased lung elasticity contribute to the airflow limitation in chronic obstructive pulmonary disease (COPD). The lesion that corresponds to loss of lung elasticity is emphysema; the small airway obstruction is due to inflammatory narrowing and obliteration. Despite their convergence in altered physiology, different mechanisms contribute to these processes. The relationships between gene expression and these specific phenotypes may be more revealing than comparison with lung function. METHODS: We measured the ratio of alveolar surface area to lung volume (SA/V) in lung tissue from 43 smokers. Two samples from 21 subjects, in which SA/V differed by >49 cm2/mL were profiled to select genes whose expression correlated with SA/V. Significant genes were tested for replication in the 22 remaining subjects. RESULTS: The level of expression of 181 transcripts was related to SA/V ( p < 0.05). When these genes were tested in the 22 remaining subjects as a replication, thirty of the 181 genes remained significantly associated with SA/V (P < 0.05) and the direction of association was the same in 164/181. Pathway and network analysis revealed enrichment of genes involved in protein ubiquitination, and western blotting showed altered expression of genes involved in protein ubiquitination in obstructed individuals. CONCLUSION: This study implicates modified protein ubiquitination and degradation as a potentially important pathway in the pathogenesis of emphysema.


Assuntos
Expressão Gênica , Pulmão/patologia , Alvéolos Pulmonares/patologia , Enfisema Pulmonar/genética , Ubiquitinação/genética , Idoso , Proteínas de Ligação a DNA/metabolismo , Regulação para Baixo , Proteínas F-Box/metabolismo , Feminino , Humanos , Medidas de Volume Pulmonar , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão/genética , Enfisema Pulmonar/metabolismo , Transdução de Sinais/genética , Fumar/fisiopatologia , Ubiquitina/metabolismo , Proteases Específicas de Ubiquitina/metabolismo , Regulação para Cima
18.
Autophagy ; 9(10): 1591-603, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23989536

RESUMO

The adaptor protein, sequestosome 1 (SQSTM1)/p62, plays an essential role in mediating selective autophagy. It serves as an autophagy receptor targeting ubiquitinated proteins to autophagosomes for degradation. In addition, it functions as a scaffold protein to regulate signaling pathways. Here we explored the interplay between coxsackievirus B3 (CVB3) and SQSTM1-mediated selective autophagy. We reported that SQSTM1 was cleaved at glycine 241 following CVB3 infection through the activity of viral protease 2A(pro). The resulting cleavage fragments of SQSTM1 were no longer the substrates of autophagy, and their ability to form protein aggregates was greatly decreased. Although the C-terminal truncation sustained the binding activity of SQSTM1 to microtubule-associated protein 1 light chain (LC3), it failed to interact with ubiquitinated proteins. It was also found that colocalization between the C-terminal fragment of SQSTM1 (SQSTM1-C) and LC3 and ubiquitin within the punctate structures was markedly disrupted. Moreover, we observed that SQSTM1-C retained the ability of SQSTM1 to stabilize antioxidant transcription factor NFE2L2 [nuclear factor (erythroid-derived 2)-like 2]; however, both the N-terminal fragment of SQSTM1 (SQSTM1-N) and SQSTM1-C lost the function of SQSTM1 in activating NFKB (the nuclear factor of kappa light polypeptide gene enhancer in B-cells) pathway. Collectively, our results suggest a novel model by which cleavage of SQSTM1 as a result of CVB3 infection impairs the function of SQSTM1 in selective autophagy and host defense signaling.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Autofagia/fisiologia , Transdução de Sinais/fisiologia , Autofagia/genética , Enterovirus Humano B/isolamento & purificação , Células HeLa , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Subunidade p50 de NF-kappa B/metabolismo , Fagossomos/metabolismo , Proteína Sequestossoma-1 , Fatores de Transcrição/metabolismo , Proteínas Ubiquitinadas/metabolismo
19.
FASEB J ; 27(7): 2777-87, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23572232

RESUMO

Coxsackievirus B3 (CVB3) is a causative agent of viral myocarditis, hepatitis, pancreatitis, and meningitis in humans. The adenosine-uridine (AU)-rich element RNA binding factor 1 (AUF1) is an integral component in the regulation of gene expression. AUF1 destabilizes mRNAs and targets them for degradation by binding to AU-rich elements in the 3' untranslated region (UTR) of mRNAs. The 3'-UTR of the CVB3 genome contains canonical AU-rich sequences, raising the possibility that CVB3 RNA may also be subjected to AUF1-mediated degradation. Here, we reported that CVB3 infection led to cytoplasmic redistribution and cleavage of AUF1. These events are independent of CVB3-induced caspase activation but require viral protein production. Overexpression of viral protease 2A reproduced CVB3-induced cytoplasmic redistribution of AUF1, while in vitro cleavage assay revealed that viral protease 3C contributed to AUF1 cleavage. Furthermore, we showed that knockdown of AUF1 facilitated viral RNA, protein, and progeny production, suggesting an antiviral property for AUF1 against CVB3 infection. Finally, an immunoprecipitation study demonstrated the physical interaction between AUF1 and the 3'-UTR of CVB3, potentially targeting CVB3 genome toward degradation. Together, our results suggest that cleavage of AUF1 may be a strategy employed by CVB3 to enhance the stability of its viral genome.


Assuntos
Citoplasma/metabolismo , Enterovirus Humano B/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas Grupo D/metabolismo , RNA Viral/metabolismo , Regiões 3' não Traduzidas/genética , Western Blotting , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Citocinas/genética , Citocinas/metabolismo , Citoplasma/virologia , Enterovirus Humano B/genética , Enterovirus Humano B/fisiologia , Expressão Gênica , Genoma Viral/genética , Células HeLa , Ribonucleoproteína Nuclear Heterogênea D0 , Ribonucleoproteínas Nucleares Heterogêneas Grupo D/genética , Interações Hospedeiro-Patógeno/genética , Humanos , Microscopia Confocal , Modelos Genéticos , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo , Ligação Proteica , Transporte Proteico , Proteólise , Interferência de RNA , Estabilidade de RNA , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Virais/genética , Proteínas Virais/metabolismo , Replicação Viral/genética
20.
Phys Med Biol ; 56(4): 1191-205, 2011 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-21285477

RESUMO

Dual-energy chest radiography has the potential to provide better diagnosis of lung disease by removing the bone signal from the image. Dynamic dual-energy radiography is now possible with the introduction of digital flat-panel detectors. The purpose of this study is to evaluate the feasibility of using dynamic dual-energy chest radiography for functional lung imaging and tumor motion assessment. The dual-energy system used in this study can acquire up to 15 frames of dual-energy images per second. A swine animal model was mechanically ventilated and imaged using the dual-energy system. Sequences of soft-tissue images were obtained using dual-energy subtraction. Time subtracted soft-tissue images were shown to be able to provide information on regional ventilation. Motion tracking of a lung anatomic feature (a branch of pulmonary artery) was performed based on an image cross-correlation algorithm. The tracking precision was found to be better than 1 mm. An adaptive correlation model was established between the above tracked motion and an external surrogate signal (temperature within the tracheal tube). This model is used to predict lung feature motion using the continuous surrogate signal and low frame rate dual-energy images (0.1-3.0 frames per second). The average RMS error of the prediction was (1.1 ± 0.3) mm. The dynamic dual energy was shown to be potentially useful for lung functional imaging such as regional ventilation and kinetic studies. It can also be used for lung tumor motion assessment and prediction during radiation therapy.


Assuntos
Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Movimento , Radiografia Torácica/métodos , Animais , Estudos de Viabilidade , Cinética , Pulmão/metabolismo , Pulmão/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/fisiopatologia , Radiografia Torácica/instrumentação
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