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1.
Mol Ther Methods Clin Dev ; 32(1): 101212, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38455264

RESUMO

T cells expressing anti-CD19 chimeric antigen receptors (CARs) have activity against chronic lymphocytic leukemia (CLL), but complete response rates range from 18% to 29%, so improvement is needed. Peripheral blood mononuclear cells (PBMCs) of CLL patients often contain high levels of CLL cells that can interfere with CAR T cell production, and T cells from CLL patients are prone to exhaustion and other functional defects. We previously developed an anti-CD19 CAR designated Hu19-CD828Z. Hu19-CD828Z has a binding domain derived from a fully human antibody and a CD28 costimulatory domain. We aimed to develop an optimized process for producing Hu19-CD828Z-expressing T cells (Hu19-CAR T) from PBMC of CLL patients. We determined that supplementing Hu19-CAR-T cultures with interleukin (IL)-7 + IL-15 had advantages over using IL-2, including greater accumulation of Hu19-CAR T cells during in vitro proliferation assays. We determined that positive selection with anti-CD4 and anti-CD8 magnetic beads was the optimal method of T cell purification because this method resulted in high T cell purity. We determined that anti-CD3/CD28 paramagnetic beads were the optimal T cell activation reagent. Finally, we developed a current good manufacturing practices-compliant clinical-scale protocol for producing Hu19-CAR T from PBMC of CLL patients. These Hu19-CAR T exhibited a full range of in vitro functions and eliminated leukemia from mice.

2.
Mol Ther ; 32(2): 503-526, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38155568

RESUMO

Multiple myeloma (MM) is a rarely curable malignancy of plasma cells. MM expresses B cell maturation antigen (BCMA). We developed a fully human anti-BCMA chimeric antigen receptor (CAR) with a heavy-chain-only antigen-recognition domain, a 4-1BB domain, and a CD3ζ domain. The CAR was designated FHVH33-CD8BBZ. We conducted the first-in-humans clinical trial of T cells expressing FHVH33-CD8BBZ (FHVH-T). Twenty-five patients with relapsed MM were treated. The stringent complete response rate (sCR) was 52%. Median progression-free survival (PFS) was 78 weeks. Of 24 evaluable patients, 6 (25%) had a maximum cytokine-release syndrome (CRS) grade of 3; no patients had CRS of greater than grade 3. Most anti-MM activity occurred within 2-4 weeks of FHVH-T infusion as shown by decreases in the rapidly changing MM markers serum free light chains, urine light chains, and bone marrow plasma cells. Blood CAR+ cell levels peaked during the time that MM elimination was occurring, between 7 and 15 days after FHVH-T infusion. C-C chemokine receptor type 7 (CCR7) expression on infusion CD4+ FHVH-T correlated with peak blood FHVH-T levels. Single-cell RNA sequencing revealed a shift toward more differentiated FHVH-T after infusion. Anti-CAR antibody responses were detected in 4 of 12 patients assessed. FHVH-T has powerful, rapid, and durable anti-MM activity.


Assuntos
Mieloma Múltiplo , Receptores de Antígenos Quiméricos , Humanos , Mieloma Múltiplo/genética , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T , Imunoterapia Adotiva , Medula Óssea/metabolismo
3.
Mol Ther Oncolytics ; 30: 132-149, 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37654973

RESUMO

To address CD19 loss from lymphoma after anti-CD19 chimeric antigen receptor (CAR) T cell therapy, we designed a bicistronic construct encoding an anti-CD19 CAR and an anti-CD20 CAR. We detected deletions from the expected bicistronic construct sequence in a minority of transcripts by mRNA sequencing. Loss of bicistronic construct transgene DNA was also detected. Deletions of sequence were present at much higher frequencies in transduced T cell mRNA versus gamma-retroviral vector RNA. We concluded that these deletions were caused by intramolecular template switching of the reverse transcriptase enzyme during reverse transcription of gamma-retroviral vector RNA into transgene DNA of transduced T cells. Intramolecular template switching was driven by repeated regions of highly similar nucleic acid sequence within CAR sequences. We optimized the sequence of the bicistronic CAR construct to reduce repeated regions of highly similar sequences. This optimization nearly eliminated sequence deletions. This work shows that repeated regions of highly similar nucleic acid sequence must be avoided in complex CAR constructs. We further optimized the bicistronic construct by lengthening the linker of the anti-CD20 single-chain variable fragment. This modification increased CD20-specific interleukin-2 release and reduced CD20-specific activation-induced cell death. We selected an optimized anti-CD19/CD20 bicistronic construct for clinical development.

4.
Leuk Lymphoma ; 63(8): 1849-1860, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35389319

RESUMO

Prolonged myelosuppression after chimeric antigen receptor (CAR) T-cell therapy is common and poorly understood. A retrospective analysis of 43 patients was conducted to investigate factors contributing to CAR T-cell-related cytopenias. Thirty-five patients were evaluable for analysis of delayed cytopenias occurring after initial hematologic recovery. Time to hematologic recovery (TTHR) was defined as number of days after CAR T-cell infusion for recovery to hemoglobin ≥8.0 g/dL, platelets ≥50.0 k/µL, and neutrophil count ≥1.0 k/µL without transfusions or growth factors for 7 days. Baseline percent bone marrow (BM) malignancy involvement correlated with TTHR (p = .0047). Patients with grades 3-4 cytokine-release syndrome (CRS) had longer TTHR than those with grades 0-2 CRS (p = .0479). Patients who developed prolonged or delayed cytopenias after anti-BCMA CAR T cells had a higher percentage of BM aspirate CAR+ cells at 2 months (n = 10; p = .0159).


Assuntos
Anemia , Leucopenia , Trombocitopenia , Anemia/etiologia , Humanos , Imunoterapia Adotiva/efeitos adversos , Estudos Retrospectivos , Fatores de Risco , Linfócitos T , Trombocitopenia/etiologia
5.
Hum Gene Ther ; 32(13-14): 730-743, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33287637

RESUMO

Chimeric antigen receptors (CARs) are artificial fusion proteins that incorporate antigen-recognition domains and T cell signaling domains. CD30 is a cell surface protein expressed on Hodgkin's lymphoma, some T cell lymphomas, and some B cell lymphomas. CD30 has a restricted expression pattern in normal cells, so CD30 has good potential as a clinical target for CAR T cells. We compared three different anti-CD30 CAR designs incorporating a single-chain variable fragment derived from the 5F11 fully human monoclonal antibody. 5F11-28Z has hinge, transmembrane, and costimulatory domains from CD28 and a CD3ζ T cell activation domain. 5F11-CD828Z has hinge and transmembrane domains from CD8α, a CD28 costimulatory domain, and a CD3ζ T cell activation domain. 5F11-CD8BBZ is identical to 5F11-CD828Z, except for the replacement of the CD28 moiety with a 4-1BB moiety. We found that T cells expressing 5F11-CD8BBZ had lower levels of CD30-specific degranulation and cytokine release compared with CD28-containing CARs. When compared to the CD28-containing CARs, T cells expressing 5F11-CD8BBZ had higher levels of nonspecific functional activity, including degranulation, cytokine release, and proliferation, when stimulated with CD30-negative target cells. We established tumors in nod-scid common gamma-chain deficient (NSG) mice and treated the tumors with T cells expressing different CARs. T cells expressing 5F11-28Z were most effective at eradicating tumors. T cells expressing 5F11-CD828Z had intermediate effectiveness, and T cells expressing 5F11-CD8BBZ were least effective. CD30+ T cells are lost from cultures of T cells containing 5F11-28Z-expressing T cells. This indicated the killing of CD30+ T cells by the 5F11-28Z-expressing T cells. Despite this, the number of T cells in the cultures consistently accumulated to numbers needed for use in a clinical trial. Based on all in vitro and murine experiments comparing the different CARs, we selected 5F11-28Z for further development, and we have initiated a clinical trial testing 5F11-28Z T cells.


Assuntos
Receptores de Antígenos Quiméricos , Anticorpos de Cadeia Única , Animais , Antígenos CD28/genética , Humanos , Imunoterapia Adotiva , Camundongos , Camundongos SCID , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos Quiméricos/genética , Linfócitos T , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Mol Ther ; 29(2): 702-717, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33129371

RESUMO

Chimeric antigen receptors (CARs) are fusion proteins that contain antigen-recognition domains and T cell signaling domains. Signaling lymphocytic-activation molecule F7 (SLAMF7) is a promising target for CAR T cell therapies of the plasma cell malignancy multiple myeloma (MM) because SLAMF7 is expressed by MM but not normal nonhematopoietic cells. We designed CARs targeting SLAMF7. We transduced human T cells with anti-SLAMF7 CARs containing either CD28 or 4-1BB costimulatory domains. T cells expressing CD28-containing CARs or 4-1BB-containing CARs recognized SLAMF7 in vitro. SLAMF7-specific cytokine release was higher for T cells expressing CARs with CD28 versus 4-1BB domains. In murine solid tumor and disseminated tumor models, anti-tumor activity of T cells was superior with CD28-containing CARs versus 4-1BB-containing CARs. Because of SLAMF7 expression on some normal leukocytes, especially natural killer cells that control certain viral infections, the inclusion of a suicide gene with an anti-SLAMF7 CAR is prudent. We designed a construct with a CD28-containing anti-SLAMF7 CAR and a suicide gene. The suicide gene encoded a dimerization domain fused to a caspase-9 domain. T cells expressing the anti-SLAMF7 CAR plus suicide-gene construct specifically recognized SLAMF7 in vitro and eliminated tumors from mice. T cells expressing this construct were eliminated on demand by administering the dimerizing agent AP1903 (rimiducid).


Assuntos
Expressão Gênica , Genes Transgênicos Suicidas/genética , Imunoterapia Adotiva , Receptores de Antígenos Quiméricos/imunologia , Família de Moléculas de Sinalização da Ativação Linfocitária/antagonistas & inibidores , Linfócitos T/imunologia , Linfócitos T/metabolismo , Animais , Modelos Animais de Doenças , Humanos , Imunoterapia Adotiva/métodos , Camundongos , Mieloma Múltiplo/imunologia , Mieloma Múltiplo/terapia , Receptores de Antígenos Quiméricos/genética , Família de Moléculas de Sinalização da Ativação Linfocitária/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Nat Commun ; 11(1): 911, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-32060262

RESUMO

Embryonal rhabdomyosarcoma (ERMS) is a childhood cancer that expresses myogenic master regulatory factor MYOD but fails to differentiate. Here, we show that the zinc finger transcription factor CASZ1 up-regulates MYOD signature genes and induces skeletal muscle differentiation in normal myoblasts and ERMS. The oncogenic activation of the RAS-MEK pathway suppresses CASZ1 expression in ERMS. ChIP-seq, ATAC-seq and RNA-seq experiments reveal that CASZ1 directly up-regulates skeletal muscle genes and represses non-muscle genes through affecting regional epigenetic modifications, chromatin accessibility and super-enhancer establishment. Next generation sequencing of primary RMS tumors identified a single nucleotide variant in the CASZ1 coding region that potentially contributes to ERMS tumorigenesis. Taken together, loss of CASZ1 activity, due to RAS-MEK signaling or genetic alteration, impairs ERMS differentiation, contributing to RMS tumorigenesis.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Desenvolvimento Muscular , Músculo Esquelético/metabolismo , Proteína MyoD/metabolismo , Miogenina/metabolismo , Rabdomiossarcoma Embrionário/metabolismo , Fatores de Transcrição/metabolismo , Animais , Carcinogênese , Proteínas de Ligação a DNA/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos SCID , Proteína MyoD/genética , Mioblastos/citologia , Mioblastos/metabolismo , Miogenina/genética , Rabdomiossarcoma Embrionário/genética , Rabdomiossarcoma Embrionário/fisiopatologia , Fatores de Transcrição/genética
9.
Nat Commun ; 11(1): 283, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31941907

RESUMO

Chimeric antigen receptor (CAR)-expressing T cells targeting B-cell maturation antigen (BCMA) have activity against multiple myeloma, but improvements in anti-BCMA CARs are needed. We demonstrated recipient anti-CAR T-cell responses against a murine single-chain variable fragment (scFv) used clinically in anti-BCMA CARs. To bypass potential anti-CAR immunogenicity and to reduce CAR binding domain size, here we designed CARs with antigen-recognition domains consisting of only a fully human heavy-chain variable domain without a light-chain domain. A CAR designated FHVH33-CD8BBZ contains a fully human heavy-chain variable domain (FHVH) plus 4-1BB and CD3ζ domains. T cells expressing FHVH33-CD8BBZ exhibit similar cytokine release, degranulation, and mouse tumor eradication as a CAR that is identical except for substitution of a scFv for FHVH33. Inclusion of 4-1BB is critical for reducing activation-induced cell death and promoting survival of T cells expressing FHVH33-containing CARs. Our results indicate that heavy-chain-only anti-BCMA CARs are suitable for evaluation in a clinical trial.


Assuntos
Cadeias Pesadas de Imunoglobulinas/metabolismo , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/imunologia , Linfócitos T/imunologia , Animais , Antígeno de Maturação de Linfócitos B/imunologia , Linhagem Celular Tumoral , Sobrevivência Celular , Células Cultivadas , Humanos , Leucócitos Mononucleares/imunologia , Camundongos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/imunologia , Domínios Proteicos/genética , Domínios Proteicos/imunologia , Engenharia de Proteínas , Receptores de Antígenos Quiméricos/metabolismo , Receptores de Fator de Crescimento Neural/genética , Receptores de Fator de Crescimento Neural/imunologia , Anticorpos de Cadeia Única/genética , Anticorpos de Cadeia Única/imunologia , Anticorpos de Cadeia Única/metabolismo
10.
Nat Med ; 26(2): 270-280, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31959992

RESUMO

Anti-CD19 chimeric antigen receptor (CAR)-expressing T cells are an effective treatment for B-cell lymphoma, but often cause neurologic toxicity. We treated 20 patients with B-cell lymphoma on a phase I, first-in-human clinical trial of T cells expressing the new anti-CD19 CAR Hu19-CD828Z (NCT02659943). The primary objective was to assess safety and feasibility of Hu19-CD828Z T-cell therapy. Secondary objectives included assessments of blood levels of CAR T cells, anti-lymphoma activity, second infusions and immunogenicity. All objectives were met. Fifty-five percent of patients who received Hu19-CD828Z T cells obtained complete remission. Hu19-CD828Z T cells had clinical anti-lymphoma activity similar to that of T cells expressing FMC63-28Z, an anti-CD19 CAR tested previously by our group, which contains murine binding domains and is used in axicabtagene ciloleucel. However, severe neurologic toxicity occurred in only 5% of patients who received Hu19-CD828Z T cells, whereas 50% of patients who received FMC63-28Z T cells experienced this degree of toxicity (P = 0.0017). T cells expressing Hu19-CD828Z released lower levels of cytokines than T cells expressing FMC63-28Z. Lower levels of cytokines were detected in blood from patients who received Hu19-CD828Z T cells than in blood from those who received FMC63-28Z T cells, which could explain the lower level of neurologic toxicity associated with Hu19-CD828Z. Levels of cytokines released by CAR-expressing T cells particularly depended on the hinge and transmembrane domains included in the CAR design.


Assuntos
Antígenos CD19/imunologia , Imunoterapia Adotiva , Linfoma de Células B/imunologia , Linfoma de Células B/terapia , Receptores de Antígenos Quiméricos/imunologia , Adolescente , Adulto , Idoso , Citocinas/metabolismo , Estudos de Viabilidade , Feminino , Humanos , Células K562 , Masculino , Pessoa de Meia-Idade , Fenótipo , Domínios Proteicos , Indução de Remissão , Adulto Jovem
11.
J Clin Oncol ; 36(22): 2267-2280, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29812997

RESUMO

Purpose Therapies with novel mechanisms of action are needed for multiple myeloma (MM). T cells can be genetically modified to express chimeric antigen receptors (CARs), which are artificial proteins that target T cells to antigens. B-cell maturation antigen (BCMA) is expressed by normal and malignant plasma cells but not normal essential cells. We conducted the first-in-humans clinical trial, to our knowledge, of T cells expressing a CAR targeting BCMA (CAR-BCMA). Patients and Methods Sixteen patients received 9 × 106 CAR-BCMA T cells/kg at the highest dose level of the trial; we are reporting results of these 16 patients. The patients had a median of 9.5 prior lines of MM therapy. Sixty-three percent of patients had MM refractory to the last treatment regimen before protocol enrollment. T cells were transduced with a γ-retroviral vector encoding CAR-BCMA. Patients received CAR-BCMA T cells after a conditioning chemotherapy regimen of cyclophosphamide and fludarabine. Results The overall response rate was 81%, with 63% very good partial response or complete response. Median event-free survival was 31 weeks. Responses included eradication of extensive bone marrow myeloma and resolution of soft-tissue plasmacytomas. All 11 patients who obtained an anti-MM response of partial response or better and had MM evaluable for minimal residual disease obtained bone marrow minimal residual disease-negative status. High peak blood CAR+ cell levels were associated with anti-MM responses. Cytokine-release syndrome toxicities were severe in some cases but were reversible. Blood CAR-BCMA T cells were predominantly highly differentiated CD8+ T cells 6 to 9 days after infusion. BCMA antigen loss from MM was observed. Conclusion CAR-BCMA T cells had substantial activity against heavily treated relapsed/refractory MM. Our results should encourage additional development of CAR T-cell therapies for MM.


Assuntos
Antígeno de Maturação de Linfócitos B/imunologia , Imunoterapia Adotiva/métodos , Mieloma Múltiplo/terapia , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/imunologia , Linfócitos T/transplante , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígeno de Maturação de Linfócitos B/genética , Ciclofosfamida/administração & dosagem , Citocinas/sangue , Citocinas/imunologia , Humanos , Mieloma Múltiplo/sangue , Mieloma Múltiplo/imunologia , Prognóstico , Receptores de Antígenos Quiméricos/sangue , Linfócitos T/imunologia , Condicionamento Pré-Transplante , Vidarabina/administração & dosagem , Vidarabina/análogos & derivados
12.
J Clin Invest ; 128(1): 446-462, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29202477

RESUMO

Pharmacologically difficult targets, such as MYC transcription factors, represent a major challenge in cancer therapy. For the childhood cancer neuroblastoma, amplification of the oncogene MYCN is associated with high-risk disease and poor prognosis. Here, we deployed genome-scale CRISPR-Cas9 screening of MYCN-amplified neuroblastoma and found a preferential dependency on genes encoding the polycomb repressive complex 2 (PRC2) components EZH2, EED, and SUZ12. Genetic and pharmacological suppression of EZH2 inhibited neuroblastoma growth in vitro and in vivo. Moreover, compared with neuroblastomas without MYCN amplification, MYCN-amplified neuroblastomas expressed higher levels of EZH2. ChIP analysis showed that MYCN binds at the EZH2 promoter, thereby directly driving expression. Transcriptomic and epigenetic analysis, as well as genetic rescue experiments, revealed that EZH2 represses neuronal differentiation in neuroblastoma in a PRC2-dependent manner. Moreover, MYCN-amplified and high-risk primary tumors from patients with neuroblastoma exhibited strong repression of EZH2-regulated genes. Additionally, overexpression of IGFBP3, a direct EZH2 target, suppressed neuroblastoma growth in vitro and in vivo. We further observed strong synergy between histone deacetylase inhibitors and EZH2 inhibitors. Together, these observations demonstrate that MYCN upregulates EZH2, leading to inactivation of a tumor suppressor program in neuroblastoma, and support testing EZH2 inhibitors in patients with MYCN-amplified neuroblastoma.


Assuntos
Sistemas CRISPR-Cas , Diferenciação Celular , Proteína Potenciadora do Homólogo 2 de Zeste , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica , Proteína Proto-Oncogênica N-Myc , Neuroblastoma , Regulação para Cima , Linhagem Celular Tumoral , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Humanos , Proteína Proto-Oncogênica N-Myc/biossíntese , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/genética , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Neurônios/metabolismo , Neurônios/patologia
13.
Mol Ther ; 25(10): 2245-2253, 2017 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-28803861

RESUMO

T cells expressing anti-CD19 chimeric antigen receptors (CARs) can induce complete remissions (CRs) of diffuse large B cell lymphoma (DLBCL). The long-term durability of these remissions is unknown. We administered anti-CD19 CAR T cells preceded by cyclophosphamide and fludarabine conditioning chemotherapy to patients with relapsed DLBCL. Five of the seven evaluable patients obtained CRs. Four of the five CRs had long-term durability with durations of remission of 56, 51, 44, and 38 months; to date, none of these four cases of lymphomas have relapsed. Importantly, CRs continued after recovery of non-malignant polyclonal B cells in three of four patients with long-term complete remissions. In these three patients, recovery of CD19+ polyclonal B cells took place 28, 38, and 28 months prior to the last follow-up, and each of these three patients remained in CR at the last follow-up. Non-malignant CD19+ B cell recovery with continuing CRs demonstrated that remissions of DLBCL can continue after the disappearance of functionally effective anti-CD19 CAR T cell populations. Patients had a low incidence of severe infections despite long periods of B cell depletion and hypogammaglobulinemia. Only one hospitalization for an infection occurred among the four patients with long-term CRs. Anti-CD19 CAR T cells caused long-term remissions of chemotherapy-refractory DLBCL without substantial chronic toxicities.


Assuntos
Antígenos CD19/imunologia , Linfoma Difuso de Grandes Células B/terapia , Receptores de Antígenos de Linfócitos T/imunologia , Adulto , Linfócitos B/imunologia , Ciclofosfamida/uso terapêutico , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Imunoterapia Adotiva/métodos , Linfoma Difuso de Grandes Células B/sangue , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/imunologia , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologia , Vidarabina/análogos & derivados , Vidarabina/uso terapêutico
14.
Cancer Cell ; 31(1): 50-63, 2017 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-28073004

RESUMO

Given the paucity of druggable mutations in high-risk neuroblastoma (NB), we undertook chromatin-focused small interfering RNA and chemical screens to uncover epigenetic regulators critical for the differentiation block in high-risk NB. High-content Opera imaging identified 53 genes whose loss of expression led to a decrease in NB cell proliferation and 16 also induced differentiation. From these, the secondary chemical screen identified SETD8, the H4K20me1 methyltransferase, as a druggable NB target. Functional studies revealed that SETD8 ablation rescued the pro-apoptotic and cell-cycle arrest functions of p53 by decreasing p53K382me1, leading to activation of the p53 canonical pathway. In pre-clinical xenograft NB models, genetic or pharmacological (UNC0379) SETD8 inhibition conferred a significant survival advantage, providing evidence for SETD8 as a therapeutic target in NB.


Assuntos
Epigênese Genética , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Neuroblastoma/tratamento farmacológico , RNA Interferente Pequeno/genética , Proteína Supressora de Tumor p53/fisiologia , Diferenciação Celular , Proliferação de Células , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/fisiologia , Humanos , Neuroblastoma/genética , Neuroblastoma/patologia , Quinazolinas/farmacologia , Proteína Supressora de Tumor p53/análise
15.
Clin Cancer Res ; 23(7): 1771-1784, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27797972

RESUMO

Purpose: Neuroblastoma is a pediatric tumor of peripheral sympathoadrenal neuroblasts. The long-term event-free survival of children with high-risk neuroblastoma is still poor despite the improvements with current multimodality treatment protocols. Activated JAK/STAT3 pathway plays an important role in many human cancers, suggesting that targeting STAT3 is a promising strategy for treating high-risk neuroblastoma.Experimental Design: To evaluate the biologic consequences of specific targeting of STAT3 in neuroblastoma, we assessed the effect of tetracycline (Tet)-inducible STAT3 shRNA and the generation 2.5 antisense oligonucleotide AZD9150 which targets STAT3 in three representative neuroblastoma cell line models (AS, NGP, and IMR32).Results: Our data indicated that Tet-inducible STAT3 shRNA and AZD9150 inhibited endogenous STAT3 and STAT3 target genes. Tet-inducible STAT3 shRNA and AZD9150 decreased cell growth and tumorigenicity. In vivo, STAT3 inhibition by Tet-inducible STAT3 shRNA or AZD9150 alone had little effect on growth of established tumors. However, when treated xenograft tumor cells were reimplanted into mice, there was a significant decrease in secondary tumors in the mice receiving AZD9150-treated tumor cells compared with the mice receiving ntASO-treated tumor cells. This indicates that inhibition of STAT3 decreases the tumor-initiating potential of neuroblastoma cells. Furthermore, inhibition of STAT3 significantly increased neuroblastoma cell sensitivity to cisplatin and decreased tumor growth and increased the survival of tumor-bearing mice in vivoConclusions: Our study supports the development of strategies targeting STAT3 inhibition in combination with conventional chemotherapy for patients with high-risk neuroblastoma. Clin Cancer Res; 23(7); 1771-84. ©2016 AACR.


Assuntos
Neuroblastoma/tratamento farmacológico , Oligonucleotídeos Antissenso/administração & dosagem , Oligonucleotídeos/administração & dosagem , Fator de Transcrição STAT3/genética , Animais , Protocolos de Quimioterapia Combinada Antineoplásica , Apoptose/efeitos dos fármacos , Carcinogênese/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cisplatino/administração & dosagem , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Neuroblastoma/genética , Neuroblastoma/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Oncotarget ; 6(29): 27628-40, 2015 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-26296975

RESUMO

The zinc finger transcription factor CASZ1 has been found to control neural fate-determination in flies, regulate murine and frog cardiac development, control murine retinal cell progenitor expansion and function as a tumor suppressor gene in humans. However, the molecular mechanism by which CASZ1 regulates gene transcription to exert these diverse biological functions has not been described. Here we identify co-factors that are recruited by CASZ1b to regulate gene transcription using co-immunoprecipitation (co-IP) and mass spectrometry assays. We find that CASZ1b binds to the nucleosome remodeling and histone deacetylase (NuRD) complex, histones and DNA repair proteins. Mutagenesis of the CASZ1b protein assay demonstrates that the N-terminus of CASZ1b is required for NuRD binding, and a poly(ADP-ribose) binding motif in the CASZ1b protein is required for histone H3 and DNA repair proteins binding. The N-terminus of CASZ1b fused to an artificial DNA-binding domain (GAL4DBD) causes a significant repression of transcription (5xUAS-luciferase assay), which could be blocked by treatment with an HDAC inhibitor. Realtime PCR results show that the transcriptional activity of CASZ1b mutants that abrogate NuRD or histone H3/DNA binding is significantly decreased. This indicates a model in which CASZ1b binds to chromatin and recruits NuRD complexes to orchestrate epigenetic-mediated transcriptional programs.


Assuntos
Reparo do DNA , Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica , Histonas/metabolismo , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Fatores de Transcrição/metabolismo , Motivos de Aminoácidos , Animais , Linhagem Celular , Epigênese Genética , Células HEK293 , Humanos , Imunoprecipitação , Espectrometria de Massas , Camundongos , Mutagênese , Mutação , Nucleossomos/química , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Recombinantes de Fusão/metabolismo , Dedos de Zinco
17.
Optom Vis Sci ; 92(3): 365-74, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25599339

RESUMO

PURPOSE: To document the degree to which Canadian optometrists are involved in the provision of low-vision (LV) care and their referral patterns. To investigate the barriers to providing optometric low-vision services (LVS). METHODS: Practicing optometrists across Canada were randomly sampled and invited to participate in a questionnaire that included questions on personal profile, primary practice profile, levels of LV care offered, patterns of referral, and barriers to provision of LV care. Questions included a combination of multiple choice and open-ended formats, and included hypothetical cases. RESULTS: A total of 459 optometrists responded (response rate, 24.8%). Optometrists estimated that 1% (range, 0 to 100%) of their patients were LV patients yet also estimated that 10% of their patients had acuity equal to or worse than 20/40. Thirty-five percent of respondents indicated that their primary practice offered LV care, 75.6% would manage a patient with minimum disability and simple goals themselves, whereas 10.7% would manage a patient with more than minimal visual disability who needed more specialized LV devices (e.g., telescopes, electronic aids, and custom-designed microscopes); 84.3% of optometrists would assess for basic magnification and lighting in a hypothetical patient with early age-related macular degeneration, whereas 15% would undertake full LV rehabilitation in advanced age-related macular degeneration. Optometrists commonly referred to CNIB (formerly the Canadian National Institute for the Blind), yet only 10.7% of respondents almost always received a written report after referral. Those who would not undertake LV assessment stated that they lacked the knowledge, equipment, or experience; that LV assessment is too time consuming; and that the cost is too prohibitive. CONCLUSIONS: This is the first comprehensive study of LVS provision by optometrists in Canada. In order for optometrists to become more involved in LVS, there is a need for more LV education, provincial health coverage of optometric LVS, and better collaboration communication between LV providers.


Assuntos
Atenção à Saúde/estatística & dados numéricos , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Optometria/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Baixa Visão/reabilitação , Adulto , Idoso , Canadá/epidemiologia , Feminino , Pesquisa sobre Serviços de Saúde , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Programas Nacionais de Saúde , Encaminhamento e Consulta/estatística & dados numéricos , Auxiliares Sensoriais , Inquéritos e Questionários
18.
Can J Ophthalmol ; 48(6): 458-62, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24314403

RESUMO

OBJECTIVE: To review the literature regarding barriers that hinder access to low-vision (LV) care from the perspective of individuals with vision impairment. DESIGN: Literature review. METHODS: PubMed and Scopus were used to identify relevant cross-sectional studies of awareness of, and barriers to, LV rehabilitation. Studies were included if they met the following criteria: (i) year of publication within the past 20 years (between 1992 and 2012), and (ii) participants of the study included individuals with vision impairment. Fourteen studies met the criteria for inclusion and were included in this review. RESULTS: Barriers to accessing low-vision service (LVS), from the perspective of individuals with vision impairment, included the following: misconceptions of LVSs, miscommunication by eye care professionals, lack of awareness, location and transportation, the need to appear independent, negative societal views, influence of family and friends, insufficient visual impairment to warrant services, cost of LVS, and reduced perception of vision loss relative to other losses in life. Other factors that were associated with lower use of LVS included income level, comorbidities, and education level. CONCLUSIONS: The reasons for not accessing LV rehabilitation are complex, and some may be more easily addressed than others. A heightened awareness of LV rehabilitation may be achieved with better communication by eye care professionals and with public education. The stigma associated with the usage of LV aids and admitting a disability still seems to exist, but may be reduced by increasing societal understanding of LV.


Assuntos
Comunicação , Custos de Cuidados de Saúde , Conhecimentos, Atitudes e Prática em Saúde , Acessibilidade aos Serviços de Saúde , Educação de Pacientes como Assunto , Baixa Visão/reabilitação , Pessoas com Deficiência Visual/psicologia , Atenção à Saúde , Humanos , Oftalmologia , Optometria
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