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Burkitt lymphoma (BL) is an aggressive lymphoma type that is currently treated by intensive chemoimmunotherapy. Despite the favorable clinical outcome for most patients with BL, chemotherapy-related toxicity and disease relapse remain major clinical challenges, emphasizing the need for innovative therapies. Using genome-scale CRISPR-Cas9 screens, we identified B-cell receptor (BCR) signaling, specific transcriptional regulators, and one-carbon metabolism as vulnerabilities in BL. We focused on serine hydroxymethyltransferase 2 (SHMT2), a key enzyme in one-carbon metabolism. Inhibition of SHMT2 by either knockdown or pharmacological compounds induced anti-BL effects in vitro and in vivo. Mechanistically, SHMT2 inhibition led to a significant reduction of intracellular glycine and formate levels, which inhibited the mTOR pathway and thereby triggered autophagic degradation of the oncogenic transcription factor TCF3. Consequently, this led to a collapse of tonic BCR signaling, which is controlled by TCF3 and is essential for BL cell survival. In terms of clinical translation, we also identified drugs such as methotrexate that synergized with SHMT inhibitors. Overall, our study has uncovered the dependency landscape in BL, identified and validated SHMT2 as a drug target, and revealed a mechanistic link between SHMT2 and the transcriptional master regulator TCF3, opening up new perspectives for innovative therapies.
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Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Linfoma de Burkitt/tratamento farmacológico , Linfoma de Burkitt/metabolismo , Glicina Hidroximetiltransferase/antagonistas & inibidores , Glicina Hidroximetiltransferase/metabolismo , Animais , Linfoma de Burkitt/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Descoberta de Drogas , Formiatos/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Glicina/metabolismo , Glicina Hidroximetiltransferase/genética , Humanos , Camundongos , Terapia de Alvo Molecular , Proteólise/efeitos dos fármacosRESUMO
BACKGROUND: Acute myeloid leukaemia (AML) is treated with intensive induction chemotherapy (IT) in medically fit patients. In general, obesity was identified as a risk factor for all-cause mortality, and there is an ongoing debate on its impact on outcome and optimal dosing strategy in obese AML patients. METHODS: We conducted a registry study screening 7632 patients and assessed the impact of obesity in 1677 equally IT treated, newly diagnosed AML patients on the outcome (OS, EFS, CR1), comorbidities, toxicities and used dosing strategies. RESULTS: Obese patients (BMI ≥ 30) displayed a significant inferior median OS (29.44 vs. 47.94 months, P = 0.015) and CR1 rate (78.7% vs. 84.3%, P = 0.015) without differences in median EFS (7.8 vs. 9.89 months, P = 0.3) compared to non-obese patients (BMI < 30). The effect was predominantly observed in older (≥60 years) patients. Obesity was identified as an independent risk factor for death, and obese patients demonstrated higher rates of cardiovascular or metabolic comorbidities. No differences for OS, EFS, CR1 or treatment-related toxicities were observed by stratification according to used dosing strategy or dose reduction. CONCLUSIONS: In conclusion, this study identifies obesity as an independent risk factor for worse OS in older AML patients undergoing curative IT most likely due to obesity-related comorbidities and not to dosing strategy.
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Epstein-Barr virus (EBV) infects human B cells and reprograms them to allow virus replication and persistence. One key viral factor in this process is latent membrane protein 2A (LMP2A), which has been described as a B cell receptor (BCR) mimic promoting malignant transformation. However, how LMP2A signaling contributes to tumorigenesis remains elusive. By comparing LMP2A and BCR signaling in primary human B cells using phosphoproteomics and transcriptome profiling, we identified molecular mechanisms through which LMP2A affects B cell biology. Consistent with the literature, we found that LMP2A mimics a subset of BCR signaling events, including tyrosine phosphorylation of the kinase SYK, the calcium initiation complex consisting of BLNK, BTK, and PLCγ2, and its downstream transcription factor NFAT. However, the majority of LMP2A-induced signaling events markedly differed from those induced by BCR stimulation. These included differential phosphorylation of kinases, phosphatases, adaptor proteins, transcription factors such as nuclear factor κB (NF-κB) and TCF3, as well as widespread changes in the transcriptional output of LMP2A-expressing B cells. LMP2A affected apoptosis and cell-cycle checkpoints by dysregulating the expression of apoptosis regulators such as BCl-xL and the tumor suppressor retinoblastoma-associated protein 1 (RB1). LMP2A cooperated with MYC and mutant cyclin D3, two oncogenic drivers of Burkitt lymphoma, to promote proliferation and survival of primary human B cells by counteracting MYC-induced apoptosis and by inhibiting RB1 function, thereby promoting cell-cycle progression. Our results indicate that LMP2A is not a pure BCR mimic but rather rewires intracellular signaling in EBV-infected B cells that optimizes cell survival and proliferation, setting the stage for oncogenic transformation.
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Herpesvirus Humano 4/metabolismo , Receptores de Antígenos de Linfócitos B/metabolismo , Proteínas da Matriz Viral/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apoptose/fisiologia , Linfócitos B/metabolismo , Humanos , Proteínas de Membrana/metabolismo , NF-kappa B/metabolismo , Fatores de Transcrição NFATC/metabolismo , Fosforilação , Transdução de Sinais , Quinase Syk/metabolismoRESUMO
Bloodstream infections (BSI) are a frequent complication in patients with hematological and oncological diseases. However, the impact of different bacterial species causing BSI and of multiple BSI remains incompletely understood. We performed a retrospective study profiling 637 bacterial BSI episodes in hematological and oncological patients. Based on the 30-day (30d) overall survival (OS), we analyzed different types of multiple BSI and grouped BSI-associated bacteria into clusters followed by further assessment of clinical and infection-related characteristics. We discovered that polymicrobial BSI (different organisms on the first day of a BSI episode) and sequential BSI (another BSI before the respective BSI episode) were associated with a worse 30d OS. Different bacterial groups could be classified into three BSI outcome clusters based on 30d OS: favorable (FAV) including mainly common skin contaminants, Escherichia spp. and Streptococcus spp.; intermediate (INT) including mainly Enterococcus spp., vancomycin-resistant Enterococcus spp., and multidrug-resistant gram-negative bacteria (MDRGN); and adverse (ADV) including MDRGN with an additional carbapenem-resistance (MDRGN+CR). A polymicrobial or sequential BSI especially influenced the outcome in the combination of two INT cluster BSI. The presence of a polymicrobial BSI and the assignment into the BSI outcome clusters were identified as independent risk factors for 30d mortality in a Cox multivariate regression analysis. The assignment to a BSI outcome cluster and the differentiated perspective of multiple BSI open new insights into the prognosis of patients with BSI and should be further validated in other patient cohorts.
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Bacteriemia/complicações , Bacteriemia/microbiologia , Doenças Hematológicas/complicações , Neoplasias Hematológicas/complicações , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Análise de Sobrevida , Adulto JovemRESUMO
Enterococcus species are commensals of the human gastrointestinal tract with the ability to cause invasive infections. For patients with hematological diseases, enterococcal bloodstream infections (BSI) constitute a serious clinical complication which may even be aggravated if the pathogen is vancomycin-resistant. Therefore, we analyzed the course of BSI due to vancomycin-susceptible enterococci (VSE) in comparison to vancomycin-resistant enterococci (VRE) on patient survival. In this retrospective single-center study, BSI were caused by VRE in 47 patients and by VSE in 43 patients. Baseline patient characteristics were similar in both groups. Concerning infection-related characteristics, an increased CRP value and an increased rate of prior colonization with multidrug-resistant organisms were detected in the VRE BSI group. More enterococcal invasive infections were found in the VSE group. The primary endpoint, overall survival (OS) at 30 days after BSI, was significantly lower in patients with VRE BSI compared to patients with VSE BSI (74.5% vs. 90.7%, p = 0.039). In a multivariate regression analysis, VRE BSI and a Charlson comorbidity index higher than 4 were independent factors associated with 30-day mortality. Moreover, we found that VRE with an additional teicoplanin resistance showed a trend towards an even lower OS.
Assuntos
Gastroenteropatias , Infecções por Bactérias Gram-Positivas , Doenças Hematológicas , Enterococos Resistentes à Vancomicina , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Gastroenteropatias/etiologia , Gastroenteropatias/mortalidade , Gastroenteropatias/terapia , Infecções por Bactérias Gram-Positivas/etiologia , Infecções por Bactérias Gram-Positivas/mortalidade , Infecções por Bactérias Gram-Positivas/terapia , Doenças Hematológicas/complicações , Doenças Hematológicas/mortalidade , Doenças Hematológicas/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
BACKGROUND: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a curative treatment option for patients with acute myeloid leukemia (AML). During transplantation, patients undergo a period of severe neutropenia, which puts them at high risk for infectious complications. However, the impact of patient colonization with multidrug-resistant organisms (MDRO) on overall survival remains unclear. METHODS: In this retrospective, single-center study, the authors analyzed data from 264 patients with AML who underwent a first allo-HSCT between January 2006 and March 2016 at their institution. Primary endpoints were overall survival and nonrelapse-related mortality. RESULTS: One hundred forty-two of 264 patients (53.8%) were colonized by at least 1 MDRO, mainly with vancomycin-resistant Enterococcus faecalis/faecium (n = 122). The characteristics of colonized patients did not differ from those of MDRO-negative patients with respect to median age (53.5 vs 53 years), cytogenetic risk according to European LeukemiaNet criteria, remission status before allo-HSCT (first or second complete remission: 55.7% vs 60.7%, respectively; active disease: 44.4% vs 39.3%, respectively), donor type, or hematopoietic cell transplantation-comorbidity index (HCT-CI). Compared with noncolonized patients, MDRO-positive patients had an inferior probability of survival at 5 years (43.3% vs 65.5%; P = .002), primarily because of a higher cumulative incidence of nonrelapse-related mortality (33.9% vs 9.4%; P < .001). Death caused by infections occurred in 15.5% of colonized patients versus 4.9% of noncolonized patients. There was no difference in the cumulative incidence of relapse in MDRO-positive versus MDRO-negative patients (33.8% vs 42.1%, respectively; P = .798). CONCLUSIONS: The current data emphasize the importance of regular MDRO screenings and prompt further investigations into the impact of colonization with MDRO on the immune system after allo-HSCT. Cancer 2018;124:286-96. © 2017 American Cancer Society.
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Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda/terapia , Adulto , Idoso , Farmacorresistência Bacteriana Múltipla , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/isolamento & purificação , Feminino , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Leucemia Mieloide Aguda/microbiologia , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Transplante Homólogo , Resistência a VancomicinaRESUMO
Infections and especially blood stream infections (BSI) with gram-negative bacteria (GNB) represent a major threat for patients with hematological diseases undergoing chemotherapy and mainly contribute to morbidity and mortality. In this retrospective single-center study, we analyzed the impact of BSI with different gram-negative multidrug-resistant bacteria (MDRGN) compared to BSI with antibiotic susceptible gram-negative bacteria. Data of 109 patients with hematological malignancies and GNB BSI were analyzed with overall survival (OS) 30 days after BSI being the primary endpoint. BSI with non-fermentative gram-negative bacteria were found in 26.6% of all patients and 73.4% suffered from a BSI with an Enterobacteriaceae. Thirty-two of 109 patients suffered from BSI with MDRGN. Characteristics of MDRGN and non-MDRGN BSI patients did not differ besides the fact that significantly more patients received an immunosuppressive therapy in the MDRGN BSI group. OS (30 days after BSI) of patients with MDRGN BSI was significantly lower (85.6 vs. 55.9%; p < 0.001) compared to patients with non-MDRGN BSI. Patients with MDRGN BSI with non-fermentative pathogens had a worse OS after 30 days compared to MDRGN BSI with Enterobacteriaceae and the same holds true for non-MDRGN BSI. In multivariate analysis of MDRGN BSI, non-fermenters and ICU admission were independently associated with increased 30-day mortality. Our data demonstrate the negative impact of non-fermentative gram-negative pathogens causing BSI compared to Enterobacteriaceae in hematological patients and thereby underlining the heterogeneity of gram-negative BSI.
Assuntos
Farmacorresistência Bacteriana Múltipla , Infecções por Enterobacteriaceae , Enterobacteriaceae , Neoplasias Hematológicas , Terapia de Imunossupressão/efeitos adversos , Adolescente , Adulto , Idoso , Intervalo Livre de Doença , Infecções por Enterobacteriaceae/etiologia , Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/mortalidade , Feminino , Neoplasias Hematológicas/sangue , Neoplasias Hematológicas/microbiologia , Neoplasias Hematológicas/mortalidade , Neoplasias Hematológicas/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
BACKGROUND: In hematology and oncology, in particular in the setting of allogeneic hematopoietic stem cell transplantation (allo-HSCT), vancomycin-resistant Enterococcus spp. (VRE) colonization rates are high due to previous hospital stays and preceding antibiotic treatment and colonized patients have a lower overall survival (OS). OBJECTIVE: We reanalyzed our previously published cohort, to unravel which colonization timepoints before and during allo-HSCT might be predictive for the subsequent outcome. PATIENTS AND METHODS: We report about 268 patients with acute myeloid leukemia receiving an allo-HSCT between 2006 and 2016. RESULTS: We identified 129 never-colonized patients, 15 previously colonized patients (positive only before admission for allo-HSCT), 41 persistently colonized patients (positive before and at admission for allo-HSCT), and 83 newly colonized patients (positive only during allo-HSCT). Persistently and newly colonized patients had a worse 60 months OS due to increased incidence of non-relapse-related mortality (NRM) than never-colonized patients (OS: never-colonized: 61.0% vs persistently colonized: 43.5%; P = 0.023 vs newly colonized: 45.6%; P = 0.046). In contrast, OS and NRM of never-colonized and previously colonized patients as well as between persistently and newly colonized patients were similar. CONCLUSION: Patients can lose their VRE colonization status and acquisition of VRE during inpatient stay for allo-HSCT decreases survival to a similar extend as persistent colonization.
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A significant increase in infections caused by multidrug-resistant organisms (MDRO) has been observed in recent years, resulting in an increase of mortality in all fields of health care. Hematological patients are particularly affected by MDRO infections because of disease- and therapy-related immunosuppression. To determine the impact of colonization with MDRO on overall survival, we retrospectively analyzed data from patients undergoing autologous hematopoietic stem cell transplantation at our institution. In total, 184 patients were identified, mainly patients with lymphomas (n = 98, 53.3%), multiple myelomas (n = 80, 43.5%), germ cell cancers (n = 5, 2.7%), or acute myeloid leukemia (n = 1, .5%). Forty patients (21.7%) tested positive for MDRO colonization. At a median follow-up time of 21.5 months, the main causes of death were infection in colonized and disease progression in noncolonized patients. Nonrelapse mortality (NRM) was higher in patients who tested positive for MDRO than in the noncolonized group (25.4% versus 3%, P < .001). Interestingly, NRM in neutropenia after autologous transplantation did not differ between colonized and noncolonized patients. Colonized patients, however, had inferior overall survival after autologous transplantation in univariate (61.7% versus 73.3%, P = .005) as well as in multivariate analysis (hazard ratio, 2.463; 95% confidence interval, 1.311 to 4.626; P = .005). We conclude that the period after discharge from hospital after autologous transplantation seems critical and patients with MDRO colonization should be observed closely for infections in the post-transplantation period in outpatient care.
Assuntos
Infecções por Bactérias Gram-Negativas/terapia , Infecções por Bactérias Gram-Positivas/terapia , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas , Neutropenia/terapia , Adulto , Idoso , Análise de Variância , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana Múltipla , Feminino , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/mortalidade , Infecções por Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções por Bactérias Gram-Positivas/mortalidade , Neoplasias Hematológicas/imunologia , Neoplasias Hematológicas/microbiologia , Neoplasias Hematológicas/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Agonistas Mieloablativos/uso terapêutico , Neutropenia/imunologia , Neutropenia/microbiologia , Neutropenia/mortalidade , Estudos Retrospectivos , Análise de Sobrevida , Condicionamento Pré-Transplante/métodos , Transplante Autólogo , Transplante Homólogo , Resultado do TratamentoRESUMO
Natural killer (NK) cells are primary defenders against cancer precursors, but cancer cells can persist by evading immune surveillance. To investigate the genetic mechanisms underlying this evasion, we perform a genome-wide CRISPR screen using B lymphoblastoid cells. SPPL3, a peptidase that cleaves glycosyltransferases in the Golgi, emerges as a top hit facilitating evasion from NK cytotoxicity. SPPL3-deleted cells accumulate glycosyltransferases and complex N-glycans, disrupting not only binding of ligands to NK receptors but also binding of rituximab, a CD20 antibody approved for treating B cell cancers. Notably, inhibiting N-glycan maturation restores receptor binding and sensitivity to NK cells. A secondary CRISPR screen in SPPL3-deficient cells identifies B3GNT2, a transferase-mediating poly-LacNAc extension, as crucial for resistance. Mass spectrometry confirms enrichment of N-glycans bearing poly-LacNAc upon SPPL3 loss. Collectively, our study shows the essential role of SPPL3 and poly-LacNAc in cancer immune evasion, suggesting a promising target for cancer treatment.
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Células Matadoras Naturais , Polissacarídeos , Humanos , Polissacarídeos/metabolismo , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/imunologia , Amino Açúcares/metabolismo , Genômica/métodos , Rituximab/farmacologia , Rituximab/metabolismo , Linhagem Celular TumoralRESUMO
Tissue-specific differences in the expression of paralog genes, which are not essential in most cell types due to the buffering effect of the partner pair, can make for highly selective gene dependencies. To identify selective paralogous targets for acute myeloid leukemia (AML), we integrated the Cancer Dependency Map with numerous datasets characterizing protein-protein interactions, paralog relationships, and gene expression in cancer models. Here, we identified ATP1B3 as a context-specific, paralog-related dependency in AML. ATP1B3, the beta subunit of the sodium-potassium pump (Na/K-ATP pump), interacts with the alpha subunit ATP1A1 to form an essential complex for maintaining cellular homeostasis and membrane potential in all eukaryotic cells. When ATP1B3's paralog ATP1B1 is poorly expressed, elimination of ATP1B3 leads to the destabilization of the Na/K-ATP pump. ATP1B1 expression is regulated through epigenetic silencing in hematopoietic lineage cells both through histone and DNA methylation in the promoter region. Loss of ATP1B3 in AML cells induced cell death in vitro and reduced leukemia burden in vivo, which could be rescued by stabilizing ATP1A1 through overexpression of ATP1B1. ATP1B3 is thus a potential therapeutic target for AML and other hematologic malignancies with low expression of ATP1B1.
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Multiple myeloma (MM) is an incurable plasma cell malignancy that exploits transcriptional networks driven by IRF4. We employ a multi-omics approach to discover IRF4 vulnerabilities, integrating functional genomics screening, spatial proteomics, and global chromatin mapping. ARID1A, a member of the SWI/SNF chromatin remodeling complex, is required for IRF4 expression and functionally associates with IRF4 protein on chromatin. Deleting Arid1a in activated murine B cells disrupts IRF4-dependent transcriptional networks and blocks plasma cell differentiation. Targeting SWI/SNF activity leads to rapid loss of IRF4-target gene expression and quenches global amplification of oncogenic gene expression by MYC, resulting in profound toxicity to MM cells. Notably, MM patients with aggressive disease bear the signature of SWI/SNF activity, and SMARCA2/4 inhibitors remain effective in immunomodulatory drug (IMiD)-resistant MM cells. Moreover, combinations of SWI/SNF and MEK inhibitors demonstrate synergistic toxicity to MM cells, providing a promising strategy for relapsed/refractory disease.
Assuntos
Proteínas de Ligação a DNA , Fatores Reguladores de Interferon , Mieloma Múltiplo , Plasmócitos , Fatores de Transcrição , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , Fatores Reguladores de Interferon/metabolismo , Fatores Reguladores de Interferon/genética , Animais , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Humanos , Camundongos , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Plasmócitos/efeitos dos fármacos , Plasmócitos/metabolismo , Plasmócitos/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Linhagem Celular Tumoral , Diferenciação Celular/efeitos dos fármacosRESUMO
Glucocorticoids have been used for decades to treat lymphomas without an established mechanism of action. Using functional genomic, proteomic, and chemical screens, we discover that glucocorticoids inhibit oncogenic signaling by the B cell receptor (BCR), a recurrent feature of aggressive B cell malignancies, including diffuse large B cell lymphoma and Burkitt lymphoma. Glucocorticoids induce the glucocorticoid receptor (GR) to directly transactivate genes encoding negative regulators of BCR stability (LAPTM5; KLHL14) and the PI3 kinase pathway (INPP5D; DDIT4). GR directly represses transcription of CSK, a kinase that limits the activity of BCR-proximal Src-family kinases. CSK inhibition attenuates the constitutive BCR signaling of lymphomas by hyperactivating Src-family kinases, triggering their ubiquitination and degradation. With the knowledge that glucocorticoids disable oncogenic BCR signaling, they can now be deployed rationally to treat BCR-dependent aggressive lymphomas and used to construct mechanistically sound combination regimens with inhibitors of BTK, PI3 kinase, BCL2, and CSK.
Assuntos
Glucocorticoides , Receptores de Antígenos de Linfócitos B , Humanos , Glucocorticoides/farmacologia , Receptores de Antígenos de Linfócitos B/metabolismo , Animais , Transdução de Sinais/efeitos dos fármacos , Receptores de Glucocorticoides/metabolismo , Camundongos , Linhagem Celular Tumoral , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma de Burkitt/tratamento farmacológico , Linfoma de Burkitt/genética , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/patologia , Terapia de Alvo Molecular/métodos , Fosfatidilinositol 3-Quinases/metabolismo , Quinases da Família src/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacosRESUMO
Polatuzumab Vedotin (Pola-V) is an antibody-drug conjugate directed to the CD79B subunit of the B cell receptor (BCR). When combined with conventional immunochemotherapy, Pola-V improves outcomes in DLBCL. To identify determinants of Pola-V sensitivity, we used CRISPR-Cas9 screening for genes that modulated Pola-V toxicity for lymphomas or the surface expression of its target, CD79B. Our results reveal the striking impact of CD79B glycosylation on Pola-V epitope availability on the lymphoma cell surface and on Pola-V toxicity. Genetic, pharmacological, and enzymatic approaches that remove sialic acid from N-linked glycans enhanced lymphoma killing by Pola-V. Pola-V toxicity was also modulated by KLHL6, an E3 ubiquitin ligase that is recurrently inactivated in germinal center derived lymphomas. We reveal how KLHL6 targets CD79B for degradation in normal and malignant germinal center B cells, thereby determining expression of the surface BCR complex. Our findings suggest precision medicine strategies to optimize Pola-V as a lymphoma therapeutic.
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Diffuse large B cell lymphoma (DLBCL) is an aggressive, profoundly heterogeneous cancer, presenting a challenge for precision medicine. Bruton's tyrosine kinase (BTK) inhibitors block B cell receptor (BCR) signaling and are particularly effective in certain molecular subtypes of DLBCL that rely on chronic active BCR signaling to promote oncogenic NF-κB. The MCD genetic subtype, which often acquires mutations in the BCR subunit, CD79B, and in the innate immune adapter, MYD88L265P, typically resists chemotherapy but responds exceptionally to BTK inhibitors. However, the underlying mechanisms of response to BTK inhibitors are poorly understood. Herein, we find a non-canonical form of chronic selective autophagy in MCD DLBCL that targets ubiquitinated MYD88L265P for degradation in a TBK1-dependent manner. MCD tumors acquire genetic and epigenetic alterations that attenuate this autophagic tumor suppressive pathway. In contrast, BTK inhibitors promote autophagic degradation of MYD88L265P, thus explaining their exceptional clinical benefit in MCD DLBCL.
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Linfoma Difuso de Grandes Células B , Humanos , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Fator 88 de Diferenciação Mieloide/farmacologia , Transdução de Sinais , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , AutofagiaRESUMO
Diffuse large B-cell lymphoma (DLBCL) can be subdivided into the activated B-cell (ABC) and germinal center B cell-like (GCB) subtypes. Self-antigen engagement of B-cell receptors (BCR) in ABC tumors induces their clustering, thereby initiating chronic active signaling and activation of NF-κB and PI3 kinase. Constitutive BCR signaling is essential in some GCB tumors but primarily activates PI3 kinase. We devised genome-wide CRISPR-Cas9 screens to identify regulators of IRF4, a direct transcriptional target of NF-κB and an indicator of proximal BCR signaling in ABC DLBCL. Unexpectedly, inactivation of N-linked protein glycosylation by the oligosaccharyltransferase-B (OST-B) complex reduced IRF4 expression. OST-B inhibition of BCR glycosylation reduced BCR clustering and internalization while promoting its association with CD22, which attenuated PI3 kinase and NF-κB activation. By directly interfering with proximal BCR signaling, OST-B inactivation killed models of ABC and GCB DLBCL, supporting the development of selective OST-B inhibitors for the treatment of these aggressive cancers. SIGNIFICANCE: DLBCL depends on constitutive BCR activation and signaling. There are currently no therapeutics that target the BCR directly and attenuate its pathologic signaling. Here, we unraveled a therapeutically exploitable, OST-B-dependent glycosylation pathway that drives BCR organization and proximal BCR signaling. This article is highlighted in the In This Issue feature, p. 1749.
Assuntos
Linfoma Difuso de Grandes Células B , NF-kappa B , Humanos , NF-kappa B/metabolismo , Glicosilação , Transdução de Sinais , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Linhagem Celular TumoralRESUMO
Integrated analysis of genomes, transcriptomes, proteomes and drug responses of cancer cell lines (CCLs) is an emerging approach to uncover molecular mechanisms of drug action. We extend this paradigm to measuring proteome activity landscapes by acquiring and integrating quantitative data for 10,000 proteins and 55,000 phosphorylation sites (p-sites) from 125 CCLs. These data are used to contextualize proteins and p-sites and predict drug sensitivity. For example, we find that Progesterone Receptor (PGR) phosphorylation is associated with sensitivity to drugs modulating estrogen signaling such as Raloxifene. We also demonstrate that Adenylate kinase isoenzyme 1 (AK1) inactivates antimetabolites like Cytarabine. Consequently, high AK1 levels correlate with poor survival of Cytarabine-treated acute myeloid leukemia patients, qualifying AK1 as a patient stratification marker and possibly as a drug target. We provide an interactive web application termed ATLANTiC (http://atlantic.proteomics.wzw.tum.de), which enables the community to explore the thousands of novel functional associations generated by this work.
Assuntos
Antineoplásicos/farmacologia , Neoplasias/tratamento farmacológico , Proteoma/metabolismo , Adenilato Quinase/metabolismo , Animais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Biologia Computacional , Simulação por Computador , Citarabina/metabolismo , Citarabina/farmacologia , Desenvolvimento de Medicamentos , Genômica , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Neoplasias/metabolismo , Proteoma/genética , Proteômica , Cloridrato de Raloxifeno/metabolismo , Cloridrato de Raloxifeno/farmacologia , Receptores de Progesterona/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/fisiologiaRESUMO
OBJECTIVES: Clostridioides difficile infections (CDI) are common in autologous (auto-HSCT) or allogenic hematopoietic stem cell transplant (allo-HSCT) recipients. However, the impact of CDI on patient outcomes is controversial. We conducted this study to examine the impact of CDI on patient outcomes. METHODS: We performed a retrospective single-center study, including 191 lymphoma patients receiving an auto-HSCT and 276 acute myeloid leukemia (AML) patients receiving an allo-HSCT. The primary endpoint was overall survival (OS). Secondary endpoints were causes of death and, for the allo-HSCT cohort, GvHD- and relapse-free survival (GRFS). RESULTS: The prevalence of CDI was 17.6% in the AML allo-HSCT and 7.3% in the lymphoma auto-HSCT cohort. A higher prevalence of bloodstream infections, but no differences concerning OS or cause of death were found for patients with CDI in the auto-HSCT cohort. [AU] In the allo-HSCT cohort, OS and GRFS were similar between CDI and non-CDI patients. However, the leading cause of death was relapse among non-CDI patients, but it was infectious diseases in the CDI group with fewer deaths due to relapse. CONCLUSIONS: CDI was not associated with worse survival in patients receiving a hematopoietic stem cell transplantation, and there were even fewer relapse-related deaths in the AML allo-HSCT cohort.
Assuntos
Clostridioides difficile , Infecções por Clostridium/fisiopatologia , Transplante de Células-Tronco Hematopoéticas , Complicações Pós-Operatórias/microbiologia , Adolescente , Adulto , Idoso , Infecções por Clostridium/mortalidade , Estudos de Coortes , Feminino , Transplante de Células-Tronco Hematopoéticas/mortalidade , Humanos , Leucemia Mieloide Aguda/terapia , Linfoma/terapia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/fisiopatologia , Recidiva , Estudos Retrospectivos , Transplante Homólogo , Adulto JovemRESUMO
Non-clear cell renal cell carcinomas (nccRCC) are rare diseases with heterogeneous histopathologically and genetically defined entities. The clinical data on optimal systemic treatments of nccRCC is rather limited. In this review, the current World Health Organization (WHO) classification of nccRCC based on histopathologic and genetic findings is reported. Regarding systemic treatment options, the most commonly used agents are mTOR inhibitors like everolimus or temsirolimus, or tyrosine kinase inhibitors like sunitinib. 2 small randomized clinical trials with nccRCC comparing sunitinib with everolimus revealed a trend towards a better progression-free survival (PFS) and overall survival (OS) in favor of sunitinib. In RCC with predominant sarcomatoid features, both chemotherapy and targeted agents are reported without any preference for outcome. For subsequent lines of therapy, some case reports describe promising effects of PD-1 or PD-L1 inhibitors in nccRCC including sarcomatoid subtype and Bellini duct carcinoma. Currently, nccRCCs are treated similarly to clear cell RCC or, whenever possible, within clinical trials. Clinical trials with immune checkpoint inhibitors are ongoing.
Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Rim/patologia , Antineoplásicos Imunológicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/patologia , Receptores Coestimuladores e Inibidores de Linfócitos T/antagonistas & inibidores , Receptores Coestimuladores e Inibidores de Linfócitos T/imunologia , Humanos , Rim/imunologia , Neoplasias Renais/imunologia , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Intervalo Livre de Progressão , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Autologous hematopoietic stem cell transplantation (auto-HSCT) provides a potentially curative treatment option for relapsed and refractory lymphomas. Obesity displays an emerging epidemic risk factor for global mortality and is associated with an increased mortality in cancer patients. To date, the impact of obesity on the outcome of lymphoma patients undergoing auto-HSCT is understudied. We conducted a retrospective single-center study assessing 119 lymphoma patients who underwent auto-HSCT. Overall survival (OS) served as the primary endpoint whereas progression free survival (PFS), cumulative incidence of non-relapse related mortality (NRM) and cumulative incidence of relapse were analyzed as secondary endpoints. Obese patients (Body mass index, BMI≥30) had significantly lower OS (45.3% vs. 77.9%; p = 0.005) and PFS (29.8% vs. 67.2%; p<0.001) compared to non-obese patients at 48 months post-transplantation. The cumulative incidence of NRM displayed no significant differences while the cumulative incidence of relapse was significantly increased in patients with BMI≥30 (66.2% vs. 21.5%; p<0.001). Patients with a BMI<25 and overweight patients (BMI 25-30; 76.1% vs. 80.9%; p = 0.585), showed no significant difference in OS, whereas patients with BMI≥30 exhibited significant lower OS when compared to either of both groups (76.1% vs. 45.3%; p = .0.021 and 80.9% vs. 45.3%; p = 0.010). Furthermore, in a multivariate analysis, obesity was identified as an independent risk factor for death (Hazard ratio 2.231; 95% CI 1.024 to 4.860; p = 0.043). Further studies are needed to evaluate the reasons for the higher relapse rate causing higher mortality in obese patients.