RESUMO
BACKGROUND: Triplet or quadruplet therapies incorporating proteasome inhibitors, immunomodulators, and anti-CD38 antibodies have led to prolonged survival among patients with newly diagnosed multiple myeloma; however, most patients have a relapse. Frontline lenalidomide therapy has increased the number of patients with lenalidomide-refractory disease at the time of the first relapse. METHODS: In this phase 3, randomized, open-label trial, we evaluated belantamab mafodotin, pomalidomide, and dexamethasone (BPd), as compared with pomalidomide, bortezomib, and dexamethasone (PVd), in lenalidomide-exposed patients who had relapsed or refractory myeloma after at least one line of therapy. The primary end point was progression-free survival. Disease response and safety were also assessed. RESULTS: A total of 302 patients underwent randomization; 155 were assigned to the BPd group, and 147 to the PVd group. At a median follow-up of 21.8 months (range, <0.1 to 39.2), the 12-month estimated progression-free survival with BPd was 71% (95% confidence interval [CI], 63 to 78), as compared with 51% (95% CI, 42 to 60) with PVd (hazard ratio for disease progression or death, 0.52; 95% CI, 0.37 to 0.73; P<0.001). Data on overall survival were immature. The percentage of patients with a response to treatment (partial response or better) was 77% (95% CI, 70 to 84) in the BPd group and 72% (95% CI, 64 to 79) in the PVd group; 40% (95% CI, 32 to 48) and 16% (95% CI, 11 to 23), respectively, had a complete response or better. Grade 3 or higher adverse events occurred in 94% of the patients in the BPd group and 76% of those in the PVd group. Ocular events occurred in 89% of the patients who received BPd (grade 3 or 4 in 43%) and 30% of those who received PVd (grade 3 or 4 in 2%); ocular events in the BPd group were managed with belantamab mafodotin dose modification. Ocular events led to treatment discontinuation in 9% of the patients in the BPd group and in no patients in the PVd group. CONCLUSIONS: Among lenalidomide-exposed patients with relapsed or refractory myeloma, BPd conferred a significantly greater benefit than PVd with respect to progression-free survival, as well as deeper, more durable responses. Ocular events were common but were controllable by belantamab mafodotin dose modification. (Funded by GSK; DREAMM-8 ClinicalTrials.gov number, NCT04484623; EudraCT number, 2018-004354-21.).
Assuntos
Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Dexametasona , Mieloma Múltiplo , Intervalo Livre de Progressão , Talidomida , Humanos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/mortalidade , Dexametasona/efeitos adversos , Dexametasona/uso terapêutico , Dexametasona/administração & dosagem , Talidomida/análogos & derivados , Talidomida/efeitos adversos , Talidomida/uso terapêutico , Talidomida/administração & dosagem , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Adulto , Idoso de 80 Anos ou mais , Bortezomib/efeitos adversos , Bortezomib/uso terapêutico , Bortezomib/administração & dosagem , Lenalidomida/efeitos adversos , Lenalidomida/uso terapêutico , Lenalidomida/administração & dosagem , Estimativa de Kaplan-Meier , RecidivaRESUMO
Molibresib is an orally bioavailable, selective, small molecule BET protein inhibitor. Results from a first time in human study in solid tumors resulted in the selection of a 75 mg once daily dose of the besylate formulation of molibresib as the recommended Phase 2 dose (RP2D). Here we present the results of Part 2 of our study, investigating safety, pharmacokinetics, pharmacodynamics and clinical activity of molibresib at the RP2D for nuclear protein in testis carcinoma (NC), small cell lung cancer, castration-resistant prostate cancer (CRPC), triple-negative breast cancer, estrogen receptor-positive breast cancer and gastrointestinal stromal tumor. The primary safety endpoints were incidence of adverse events (AEs) and serious AEs; the primary efficacy endpoint was overall response rate. Secondary endpoints included plasma concentrations and gene set enrichment analysis (GSEA). Molibresib 75 mg once daily demonstrated no unexpected toxicities. The most common treatment-related AEs (any grade) were thrombocytopenia (64%), nausea (43%) and decreased appetite (37%); 83% of patients required dose interruptions and 29% required dose reductions due to AEs. Antitumor activity was observed in NC and CRPC (one confirmed partial response each, with observed reductions in tumor size), although predefined clinically meaningful response rates were not met for any tumor type. Total active moiety median plasma concentrations after single and repeated administration were similar across tumor cohorts. GSEA revealed that gene expression changes with molibresib varied by patient, response status and tumor type. Investigations into combinatorial approaches that use BET inhibition to eliminate resistance to other targeted therapies are warranted.
Assuntos
Benzodiazepinas/uso terapêutico , Neoplasias/tratamento farmacológico , Proteínas Nucleares/metabolismo , Neoplasias Testiculares/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Benzodiazepinas/administração & dosagem , Benzodiazepinas/efeitos adversos , Benzodiazepinas/farmacocinética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/antagonistas & inibidores , Receptores de Superfície Celular/antagonistas & inibidores , Adulto JovemRESUMO
Belantamab mafodotin (belamaf) is a BCMA-targeted antibody-drug conjugate recently approved as monotherapy for adults with relapsed/refractory multiple myeloma who have received ≥4 prior therapies. Belamaf binds to BCMA and eliminates myeloma cells by multimodal mechanisms of action. The cytotoxic and potential immunomodulatory properties of belamaf have led to novel combination studies with other anticancer therapies. Here, we describe the rationale and design of DREAMM-5, an ongoing Phase I/II platform study evaluating the safety and efficacy of belamaf combined with novel agents, including GSK3174998 (OX40 agonist), feladilimab (an ICOS; GSK3359609), nirogacestat (a gamma-secretase inhibitor; PF-03084014) and dostarlimab (a PD-1 blocker) versus belamaf monotherapy for patients with relapsed/refractory multiple myeloma. Clinical trial registration: NCT04126200 (ClinicalTrials.gov).
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígeno de Maturação de Linfócitos B/antagonistas & inibidores , Mieloma Múltiplo/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Receptores OX40/antagonistas & inibidores , Projetos de Pesquisa/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/administração & dosagem , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como Assunto , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Mieloma Múltiplo/imunologia , Mieloma Múltiplo/patologia , Recidiva Local de Neoplasia/imunologia , Recidiva Local de Neoplasia/patologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Tetra-Hidronaftalenos/administração & dosagem , Valina/administração & dosagem , Valina/análogos & derivados , Adulto JovemRESUMO
Current frontline therapies for newly diagnosed multiple myeloma patients have significantly prolonged progression-free survival (PFS). This has led to interest in minimal residual disease negativity (MRDng) as an efficacy-response biomarker and possible surrogate endpoint. A meta-analysis was conducted to explore the surrogacy of MRD for PFS and quantify the relationship between MRDng rates and PFS at the trial level. A systematic search was conducted on phase II and III trials reporting MRDng rates along with median PFS (mPFS) or PFS hazard ratios (HR). Weighted linear regressions were conducted relating mPFS to MRDng rates, and relating PFS HRs to either odds ratios (OR) or rate differences (RD) for MRDng in comparative trials. A total of 14 trials were available for the mPFS analysis. log(MRDng rate) was moderately associated with log (mPFS), with a slope of ß = 0.37 (95% CI, 0.26 to 0.48) and R2 = 0.62. A total of 13 trials were available for the PFS HR analysis. Treatment effects on MRDng rates were correlated with the corresponding effects on PFS: log (PFS HR) and log (MRDng OR) had a moderate association with ß = -0.36 (95% CI, -0.56 to -0.17) and R2 = 0.53 (95% CI, 0.21 to 0.77); log (PFS HR) and the MRDng RD had a stronger association with slope ß = -0.03 (95% CI, -0.04 to -0.02) and R2 = 0.67 (95% CI, 0.31 to 0.86). MRDng rates moderately associate with PFS outcomes. MRDng RDs are more strongly associated with HRs than MRDng ORs, with evidence suggestive of potential surrogacy.
Assuntos
Mieloma Múltiplo , Humanos , Mieloma Múltiplo/terapia , Intervalo Livre de Progressão , Neoplasia Residual , Resultado do Tratamento , Intervalo Livre de Doença , BiomarcadoresRESUMO
Belantamab mafodotin, a B-cell maturation antigen-targeting antibody-drug conjugate (ADC), was investigated in Japanese patients with relapsed/refractory multiple myeloma in Part 1 of the phase I DREAMM-11 study. Patients who had received ≥ 2 prior lines of therapy including a proteasome inhibitor and immunomodulatory agent were eligible. Eight patients received belantamab mafodotin monotherapy at 2.5 mg/kg (n = 4) or 3.4 mg/kg (n = 4) by intravenous infusion every 3 weeks on day 1 of each cycle until disease progression or unacceptable toxicity. Primary objectives were tolerability and safety, and secondary objectives included pharmacokinetics (PK) and efficacy. The most common Grade ≥ 3 adverse event was thrombocytopenia/platelet count decreased (2.5 mg/kg cohort, 100% [4/4]; 3.4 mg/kg cohort, 75% [3/4]), and no dose-limiting toxicities were observed. Ocular events, including keratopathy findings, were observed in most patients (2.5 mg/kg cohort, 100% [4/4]; 3.4 mg/kg cohort, 75% [3/4]) and were managed with dose modifications. All resolved within the study period. Overall response rates were 50% (2/4) in the 2.5 mg/kg cohort and 25% (1/4) in the 3.4 mg/kg cohort. Although PK profiles in Japanese patients varied, individual exposures overlapped with previous results in Western populations. Belantamab mafodotin monotherapy was generally well-tolerated and demonstrated clinical activity at both doses.
Assuntos
Mieloma Múltiplo , Humanos , Mieloma Múltiplo/tratamento farmacológico , População do Leste Asiático , Anticorpos Monoclonais Humanizados/uso terapêutico , Inibidores de ProteassomaRESUMO
PURPOSE: Molibresib is a selective, small molecule inhibitor of the bromodomain and extra-terminal (BET) protein family. This was an open-label, two-part, Phase I/II study investigating molibresib monotherapy for the treatment of hematological malignancies (NCT01943851). PATIENTS AND METHODS: Part 1 (dose escalation) determined the recommended Phase 2 dose (RP2D) of molibresib in patients with acute myeloid leukemia (AML), Non-Hodgkin lymphoma (NHL), or multiple myeloma. Part 2 (dose expansion) investigated the safety and efficacy of molibresib at the RP2D in patients with relapsed/refractory myelodysplastic syndrome (MDS; as well as AML evolved from antecedent MDS) or cutaneous T-cell lymphoma (CTCL). The primary endpoint in Part 1 was safety and the primary endpoint in Part 2 was objective response rate (ORR). RESULTS: There were 111 patients enrolled (87 in Part 1, 24 in Part 2). Molibresib RP2Ds of 75 mg daily (for MDS) and 60 mg daily (for CTCL) were selected. Most common Grade 3+ adverse events included thrombocytopenia (37%), anemia (15%), and febrile neutropenia (15%). Six patients achieved complete responses [3 in Part 1 (2 AML, 1 NHL), 3 in Part 2 (MDS)], and 7 patients achieved partial responses [6 in Part 1 (4 AML, 2 NHL), 1 in Part 2 (MDS)]. The ORRs for Part 1, Part 2, and the total study population were 10% [95% confidence interval (CI), 4.8-18.7], 25% (95% CI, 7.3-52.4), and 13% (95% CI, 6.9-20.6), respectively. CONCLUSIONS: While antitumor activity was observed with molibresib, use was limited by gastrointestinal and thrombocytopenia toxicities. Investigations of molibresib as part of combination regimens may be warranted.
Assuntos
Neoplasias Hematológicas , Leucemia Mieloide Aguda , Linfoma não Hodgkin , Trombocitopenia , Humanos , Linfoma não Hodgkin/tratamento farmacológico , Neoplasias Hematológicas/tratamento farmacológico , Leucemia Mieloide Aguda/tratamento farmacológicoRESUMO
Molibresib (GSK525762), an orally bioavailable small molecule with 2 major equipotent active metabolites, is being developed for the treatment of cancers. Molibresib is a substrate of cytochrome P450 (CYP) 3A4 and P-glycoprotein (P-gp). To enable administering safe doses of molibresib to healthy volunteers, this 2-part randomized, open-label, crossover drug-drug interaction trial was conducted as an adaptive design study using physiologically based pharmacokinetic (PBPK) modeling and simulation to predict the lowest doses of molibresib that could be safely administered alone (10 mg) or with itraconazole and rifampicin (strong inhibitors and inducers of CYP3A and P-gp, respectively). PBPK simulation guided the molibresib dose (5 mg) to be administered along with itraconazole in part 1. Itraconazole increased total exposure (AUC) of molibresib by 4.15-fold with a 66% increase in Cmax , whereas the total AUC and Cmax for the 2 major active metabolites of molibresib decreased by about 70% and 87%, respectively. A second PBPK simulation was conducted with part 1 data to also include the active metabolites to update the recommendation for the molibresib dose (20 mg) with rifampicin. With rifampicin, the AUC and Cmax of molibresib decreased by approximately 91% and 80%, respectively, whereas the AUC of the 2 active metabolites decreased to a lesser extent (8%), with a 2-fold increase in Cmax . The results of this study confirmed the in vitro data that molibresib is a substrate for CYP3A4. The adaptive design, including Simcyp simulations, allowed evaluation of 2 drug interactions of an oncology drug in a single trial, thus minimizing time and exposures administered to healthy subjects.
Assuntos
Benzodiazepinas/farmacocinética , Indutores do Citocromo P-450 CYP3A/farmacologia , Inibidores do Citocromo P-450 CYP3A/farmacologia , Itraconazol/farmacologia , Rifampina/farmacologia , Adulto , Área Sob a Curva , Estudos Cross-Over , Relação Dose-Resposta a Droga , Interações Medicamentosas , Feminino , Voluntários Saudáveis , Humanos , Taxa de Depuração Metabólica , Pessoa de Meia-IdadeRESUMO
Non-genetic drug resistance is increasingly recognised in various cancers. Molecular insights into this process are lacking and it is unknown whether stable non-genetic resistance can be overcome. Using single cell RNA-sequencing of paired drug naïve and resistant AML patient samples and cellular barcoding in a unique mouse model of non-genetic resistance, here we demonstrate that transcriptional plasticity drives stable epigenetic resistance. With a CRISPR-Cas9 screen we identify regulators of enhancer function as important modulators of the resistant cell state. We show that inhibition of Lsd1 (Kdm1a) is able to overcome stable epigenetic resistance by facilitating the binding of the pioneer factor, Pu.1 and cofactor, Irf8, to nucleate new enhancers that regulate the expression of key survival genes. This enhancer switching results in the re-distribution of transcriptional co-activators, including Brd4, and provides the opportunity to disable their activity and overcome epigenetic resistance. Together these findings highlight key principles to help counteract non-genetic drug resistance.
Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Leucemia Mieloide Aguda/tratamento farmacológico , Transativadores/antagonistas & inibidores , Animais , Antineoplásicos/uso terapêutico , Medula Óssea/patologia , Sistemas CRISPR-Cas/genética , Linhagem Celular Tumoral , Epigênese Genética/efeitos dos fármacos , Feminino , Células HEK293 , Humanos , Estimativa de Kaplan-Meier , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/patologia , Camundongos , Camundongos Endogâmicos C57BL , Análise de Sequência de RNA , Análise de Célula Única , Transativadores/genética , Transativadores/metabolismo , Transcrição Gênica/efeitos dos fármacos , Resultado do Tratamento , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Mammalian septins constitute a family of at least 12 GTP-binding proteins that can form hetero-oligomers and that are sometimes found in association with actin or microtubule filaments. However, their functions are not understood. Using RNA interference, we found that suppression of septin expression in HeLa cells caused a pronounced increase in microtubule stability. Mass spectroscopic analysis of proteins coprecipitating with Sept6 identified the microtubule-associated protein MAP4 as a septin binding partner. A small, proline-rich region in the C-terminal half of MAP4 bound directly to a Sept 2:6:7 heterotrimer, and to the Sept2 monomer. The trimer blocked the ability of this MAP4 fragment to bind and bundle microtubules in vitro. In intact cells, MAP4 was required for the stabilization of microtubules induced by septin depletion. Moreover, septin depletion increased the number of cells with abnormal nuclei, and this effect was blocked by gene silencing of MAP4. These data identify a novel molecular function for septins in mammalian cells: the modulation of microtubule dynamics through interaction with MAP4.
Assuntos
Proteínas de Ciclo Celular/fisiologia , Proteínas de Ligação ao GTP/fisiologia , Proteínas Associadas aos Microtúbulos/fisiologia , Microtúbulos/fisiologia , Monoéster Fosfórico Hidrolases/fisiologia , Sequência de Aminoácidos , Proteínas de Ciclo Celular/genética , Proteínas do Citoesqueleto , Dimerização , Proteínas de Ligação ao GTP/genética , Células HeLa , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/efeitos dos fármacos , Mitose , Dados de Sequência Molecular , Monoéster Fosfórico Hidrolases/genética , Ligação Proteica , RNA Interferente Pequeno/genética , SeptinasRESUMO
The interactions between serum response factor (SRF) and CArG elements are critical for smooth muscle cell (SMC) marker gene transcription. However, the mechanisms whereby SRF, which is expressed ubiquitously, contributes to SMC-specific transcription are unknown. Myocardin was recently cloned as a coactivator of SRF in the heart, but its role in regulating CArG-dependent expression of SMC differentiation marker genes has not been clearly elucidated. In this study, we examined the expression and the function of myocardin in SMCs. In adult mice, myocardin mRNA was expressed in multiple smooth muscle (SM) tissues including the aorta, bladder, stomach, intestine, and colon, as well as the heart. Myocardin was also expressed in cultured rat aortic SMCs and A404 SMC precursor cells. Of particular interest, expression of myocardin was induced during differentiation of A404 cells, although it was not expressed in parental P19 cells from which A404 cells were derived. Cotransfection studies in SMCs revealed that myocardin induced the activity of multiple SMC marker gene promoters including SM alpha-actin, SM-myosin heavy chain, and SM22alpha by 9- to 60-fold in a CArG-dependent manner, whereas myocardin short interfering RNA markedly decreased activity of these promoters. Moreover, adenovirus-mediated overexpression of a dominant-negative form of myocardin significantly suppressed expression of endogenous SMC marker genes, whereas adenovirus-mediated overexpression of wild-type myocardin increased expression. Taken together, results provide compelling evidence that myocardin plays a key role as a transcriptional coactivator of SMC marker genes through CArG-dependent mechanisms.
Assuntos
Músculo Liso Vascular/metabolismo , Proteínas Nucleares/genética , Elementos de Resposta/genética , Transativadores/genética , Transcrição Gênica/genética , Células 3T3 , Animais , Biomarcadores , Linhagem Celular , Células Cultivadas , Ensaio de Desvio de Mobilidade Eletroforética , Expressão Gênica , Regulação da Expressão Gênica , Vetores Genéticos/genética , Camundongos , Músculo Liso Vascular/citologia , Mutação , Miocárdio/citologia , Miocárdio/metabolismo , Proteínas Nucleares/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/fisiologia , Ratos , Elementos de Resposta/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Resposta Sérica/metabolismo , Transativadores/fisiologia , TransfecçãoRESUMO
UNLABELLED: Next-generation sequencing was used to identify Notch mutations in a large collection of diverse solid tumors. NOTCH1 and NOTCH2 rearrangements leading to constitutive receptor activation were confined to triple-negative breast cancers (TNBC; 6 of 66 tumors). TNBC cell lines with NOTCH1 rearrangements associated with high levels of activated NOTCH1 (N1-ICD) were sensitive to the gamma-secretase inhibitor (GSI) MRK-003, both alone and in combination with paclitaxel, in vitro and in vivo, whereas cell lines with NOTCH2 rearrangements were resistant to GSI. Immunohistochemical staining of N1-ICD in TNBC xenografts correlated with responsiveness, and expression levels of the direct Notch target gene HES4 correlated with outcome in patients with TNBC. Activating NOTCH1 point mutations were also identified in other solid tumors, including adenoid cystic carcinoma (ACC). Notably, ACC primary tumor xenografts with activating NOTCH1 mutations and high N1-ICD levels were sensitive to GSI, whereas N1-ICD-low tumors without NOTCH1 mutations were resistant. SIGNIFICANCE: NOTCH1 mutations, immunohistochemical staining for activated NOTCH1, and HES4 expression are biomarkers that can be used to identify solid tumors that are likely to respond to GSI-based therapies.
Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Antineoplásicos/farmacologia , Carcinoma Adenoide Cístico/genética , Inibidores de Proteases/farmacologia , Neoplasias de Mama Triplo Negativas/genética , Animais , Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Apoptose/genética , Biomarcadores , Carcinoma Adenoide Cístico/tratamento farmacológico , Carcinoma Adenoide Cístico/metabolismo , Linhagem Celular Tumoral , Senescência Celular/efeitos dos fármacos , Óxidos S-Cíclicos/farmacologia , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/genética , Exoma , Feminino , Regulação Neoplásica da Expressão Gênica , Rearranjo Gênico , Genes myc , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Modelos Moleculares , Mutação , Prognóstico , Inibidores de Proteases/administração & dosagem , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Receptores Notch/antagonistas & inibidores , Receptores Notch/química , Receptores Notch/genética , Receptores Notch/metabolismo , Transdução de Sinais/efeitos dos fármacos , Tiadiazóis/farmacologia , Resultado do Tratamento , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Post-transplant lymphoproliferative disorder (PTLD) is a complication of organ transplantation. The risk of developing PTLD varies depending on a number of factors, including the organ transplanted and the degree of immunosuppression used. METHODS: We report a retrospective analysis of 35 patients with PTLD treated at our center after lung transplantation. Of 705 patients who received allografts, 34 (4.8%) developed PTLD. One patient underwent transplantation elsewhere and was treated at our center. RESULTS: PTLD involved the allograft in 49% of our patients and the gastrointestinal (GI) tract lumen in 23%. Histologically, 39% of tumors were monomorphic and 48% polymorphic. The time to presentation defined the location and histology of disease. Of 17 patients diagnosed within 11 months of transplantation, PTLD involved the allograft in 12 (71%) and the GI tract in 1 (p = 0.01). This "early" PTLD was 85% polymorphic (p = 0.006). Conversely, of the 18 patients diagnosed more than 11 months after transplant, the lung was involved in 5 (28%) and the GI tract in 7 (39%; p = 0.01). "Late" PTLD was 71% monomorphic (p = 0.006). Median overall survival after diagnosis was 18.57 months. Overall survival did not differ between all lung transplant recipients and those who developed PTLD. CONCLUSIONS: PTLD is an uncommon complication after lung transplantation, and its incidence declined remarkably in the era of modern immunosuppression. We report several factors that are important for predisposition toward, progression of, and treatment of PTLD after lung transplantation.
Assuntos
Transplante de Pulmão/efeitos adversos , Transplante de Pulmão/imunologia , Transtornos Linfoproliferativos/epidemiologia , Transtornos Linfoproliferativos/patologia , Adulto , Idoso , Feminino , Seguimentos , Trato Gastrointestinal/patologia , Humanos , Terapia de Imunossupressão , Incidência , Estimativa de Kaplan-Meier , Pulmão/patologia , Transplante de Pulmão/mortalidade , Transtornos Linfoproliferativos/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Taxa de SobrevidaRESUMO
Mammalian septins are GTP-binding proteins the functions of which are not well understood. Knockdown of SEPT2, 6, and 7 causes stress fibers to disintegrate and cells to lose polarity. We now show that this phenotype is induced by nuclear accumulation of the adaptor protein NCK, as the effects can be reversed or induced by cytoplasmic or nuclear NCK, respectively. NCK is carried into the nucleus by SOCS7 (suppressor of cytokine signaling 7), which possesses nuclear import/export signals. SOCS7 interacts with septins and NCK through distinct domains. DNA damage induces actin and septin rearrangement and rapid nuclear accumulation of NCK and SOCS7. Moreover, NCK expression is essential for cell-cycle arrest. The septin-SOCS7-NCK axis intersects with the canonical DNA damage cascade downstream of ATM/ATR and is essential for p53 Ser15 phosphorylation. These data illuminate an unanticipated connection between septins, SOCS7, NCK signaling, and the DNA damage response.
Assuntos
Actinas/metabolismo , Proteínas de Ciclo Celular/metabolismo , Ciclo Celular , Núcleo Celular/metabolismo , Dano ao DNA , Proteínas de Ligação ao GTP/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Oncogênicas/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Transporte Ativo do Núcleo Celular , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas Mutadas de Ataxia Telangiectasia , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/efeitos da radiação , Proteínas de Ciclo Celular/genética , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/efeitos da radiação , Proliferação de Células , Forma Celular , Citoplasma/metabolismo , Proteínas do Citoesqueleto , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação ao GTP/genética , Células HeLa , Humanos , Hidroxiureia/farmacologia , Camundongos , Camundongos Knockout , Mitomicina/farmacologia , Complexos Multiproteicos/metabolismo , Mutagênicos/farmacologia , Proteínas Nucleares/genética , Proteínas Oncogênicas/genética , Fenótipo , Monoéster Fosfórico Hidrolases/genética , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Septinas , Transdução de Sinais , Proteínas Supressoras da Sinalização de Citocina/genética , Fatores de Tempo , Transfecção , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Raios UltravioletaRESUMO
Septins constitute a family of guanine nucleotide-binding proteins that were first discovered in the yeast Saccharomyces cerevisiae but are also present in many other eukaryotes. In yeast they congregate at the bud neck and are required for cell division. Their function in metazoan cells is uncertain, but they have been implicated in exocytosis and cytokinesis. Septins have been purified from cells as hetero-oligomeric filaments, but their mechanism of assembly is unknown. Further studies have been limited by the difficulty in expressing functional septin proteins in bacteria. We now show that stable, soluble septin heterodimers can be produced by co-expression from bicistronic vectors in bacteria and that the co-expression of three septins results in their assembly into filaments. Pre-assembled dimers and trimers bind guanine nucleotide and show a slow GTPase activity. The assembly of a heterodimer from monomers in vitro is accompanied by GTP hydrolysis. Borg3, a downstream effector of the Cdc42 GTPase, binds specifically to a septin heterodimer composed of Sept6 and Sept7 and to the Sept2/6/7 trimer, but not to septin monomers or to other heterodimers. Septins associate through their C-terminal coiled-coil domains, and Borg3 appears to recognize the interface between these domains in Sept6 and Sept7.