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Chronic lymphocytic leukemia (CLL) is a monoclonal B-cell lymphoproliferative disease with a high annual incidence in Western countries. As B-cell receptor (BCR) signaling and intrinsic apoptotic resistance play critical roles in the development and survival of CLL cells, therapeutic approaches targeting these pathways have been extensively investigated to tackle this incurable disease. Over the last decade, several Phase 3 trials have confirmed the superior efficacy of covalent Bruton tyrosine kinase inhibitors (cBTKis) and venetoclax, a selective B-cell lymphoma 2 (BCL2) inhibitor, over chemoimmunotherapy. This has been demonstrated in both the treatment-naïve and relapsed/refractory (RR) settings and includes patients with high-risk molecular features. However, these drugs are not curative, with patients continuing to relapse after treatment with both cBTKis and BCL2is, and the optimal treatment strategy for these patients has not been defined. Several novel agents with distinct mechanisms have recently been developed for CLL which have demonstrated efficacy in patients who have previously received cBTKis and BCL2i. In particular, novel BCR-signaling targeting agents have shown promising efficacy in early-phase clinical trials for RR-CLL. Furthermore, cancer immunotherapies such as bispecific antibodies and chimeric antigen receptor T-cells have also shown anti-tumor activity in patients with heavily pretreated RR-CLL. Personalised approaches with these novel agents and combination strategies based on the understanding of resistance mechanisms have the potential to overcome the clinical challenge of what to do next for a patient who has already had a cBTKi and venetoclax.
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MYC can be considered to be one of the most pressing and important targets for the development of novel anti-cancer therapies. This is due to its frequent dysregulation in tumors and due to the wide-ranging impact this dysregulation has on gene expression and cellular behavior. As a result, there have been numerous attempts to target MYC over the last few decades, both directly and indirectly, with mixed results. This article reviews the biology of MYC in the context of cancers and drug development. It discusses strategies aimed at targeting MYC directly, including those aimed at reducing its expression and blocking its function. In addition, the impact of MYC dysregulation on cellular biology is outlined, and how understanding this can underpin the development of approaches aimed at molecules and pathways regulated by MYC. In particular, the review focuses on the role that MYC plays in the regulation of metabolism, and the therapeutic avenues offered by inhibiting the metabolic pathways that are essential for the survival of MYC-transformed cells.
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The development of inhibitors of Bruton tyrosine kinase (BTK) and B-cell lymphoma 2 (BCL2) has resulted in a paradigm shift in the treatment of chronic lymphocytic leukaemia (CLL) over the last decade. Observations regarding the importance of B-cell receptor signalling for the survival and proliferation of CLL cells led to the development of the first-in-class BTK inhibitor (BTKi), ibrutinib, for the treatment of CLL. Despite being better tolerated than chemoimmunotherapy, ibrutinib does have side effects, some of which are due to the off-target inhibition of kinases other than BTK. As a result, more specific inhibitors of BTK were developed, such as acalabrutinib and zanubrutinib, which have demonstrated equivalent/enhanced efficacy and improved tolerability in large randomized clinical trials. Despite the increased specificity for BTK, side effects and treatment resistance remain therapeutic challenges. As these drugs all bind covalently to BTK, an alternative approach was to develop noncovalent inhibitors of BTK, including pirtobrutinib and nemtabrutinib. The alternative mechanisms of BTK-binding of these agents has the potential to overcome resistance mutations, something that has been borne out in early clinical trial data. A further step in the clinical development of BTK inhibition has been the introduction of BTK degraders, which remove BTK by ubiquitination and proteasomal degradation, in marked contrast to BTK inhibition. This article will review the evolution of BTK inhibition for CLL and offer future perspectives on the sequencing of an increasing number of different agents, and how this may be impacted on by mutations in BTK itself and other kinases.
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Breath analysis is a promising non-invasive method for the detection and management of lung cancer. Exhaled breath contains a complex mixture of volatile and non-volatile organic compounds that are produced as end-products of metabolism. Several studies have explored the patterns of these compounds and have postulated that a unique breath signature is emitted in the setting of lung cancer. Most studies have evaluated the use of gas chromatography and mass spectrometry to identify these unique breath signatures. With recent advances in the field of analytical chemistry and machine learning gaseous chemical sensing and identification devices have also been created to detect patterns of odorant molecules such as volatile organic compounds. These devices offer hope for a point-of-care test in the future. Several prospective studies have also explored the presence of specific genomic aberrations in the exhaled breath of patients with lung cancer as an alternative method for molecular analysis. Despite its potential, the use of breath analysis has largely been limited to translational research due to methodological issues, the lack of standardization or validation and the paucity of large multi-center studies. It is clear however that it offers a potentially non-invasive alternative to investigations such as tumor biopsy and blood sampling.
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Neoplasias Pulmonares , Compostos Orgânicos Voláteis , Humanos , Testes Respiratórios/métodos , Misturas Complexas , Neoplasias Pulmonares/patologia , Estudos Prospectivos , Compostos Orgânicos Voláteis/análiseRESUMO
It has been unclear what role metabolism is playing in the pathophysiology of chronic lymphocytic leukemia (CLL). One reason is that the study of CLL metabolism is challenging due to the resting nature of circulating CLL cells. Also, it is not clear if any of the genomic aberrations observed in this disease have any impact on metabolism. Here, we demonstrate that CLL cells in proliferation centers exhibit upregulation of several molecules involved in glycolysis and mitochondrial metabolism. Comparison of CXCR4/CD5 intraclonal cell subpopulations showed that these changes are paralleled by increases in the metabolic activity of the CXCR4lowCD5high fraction that have recently egressed from the lymph nodes. Notably, anti-IgM stimulation of CLL cells recapitulates many of these metabolic alterations, including increased glucose uptake, increased lactate production, induction of glycolytic enzymes, and increased respiratory reserve. Treatment of CLL cells with inhibitors of B-cell receptor (BCR) signaling blocked these anti-IgM-induced changes in vitro, which was mirrored by decreases in hexokinase 2 expression in CLL cells from ibrutinib-treated patients in vivo. Interestingly, several samples from patients with 17p-deletion manifested increased spontaneous aerobic glycolysis in the unstimulated state suggestive of a BCR-independent metabolic phenotype. We conclude that the proliferative fraction of CLL cells found in lymphoid tissues or the peripheral blood of CLL patients exhibit increased metabolic activity when compared with the bulk CLL-cell population. Although this is due to microenvironmental stimulatory signals such as BCR-engagement in most cases, increases in resting metabolic activity can be observed in cases with 17p-deletion.
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The synthesis of serine from glucose is a key metabolic pathway supporting cellular proliferation in healthy and malignant cells. Despite this, the role that this aspect of metabolism plays in germinal center biology and pathology is not known. Here, we performed a comprehensive characterization of the role of the serine synthesis pathway in germinal center B cells and lymphomas derived from these cells. We demonstrate that upregulation of a functional serine synthesis pathway is a metabolic hallmark of B cell activation and the germinal center reaction. Inhibition of phosphoglycerate dehydrogenase (PHGDH), the first and rate-limiting enzyme in this pathway, led to defective germinal formation and impaired high-affinity antibody production. In addition, overexpression of enzymes involved in serine synthesis was a characteristic of germinal center B cell-derived lymphomas, with high levels of expression being predictive of reduced overall survival in diffuse large B cell lymphoma. Inhibition of PHGDH induced apoptosis in lymphoma cells, reducing disease progression. These findings establish PHGDH as a critical player in humoral immunity and a clinically relevant target in lymphoma.
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Linfoma de Células B , Linfoma , Proliferação de Células , Centro Germinativo , Humanos , Linfoma/genética , Linfoma de Células B/genética , Fosfoglicerato Desidrogenase/genética , Fosfoglicerato Desidrogenase/metabolismo , Serina/metabolismoRESUMO
The coronavirus disease 2019 (COVID-19) pandemic has caused considerable global disruption to clinical practice. This article will review the impact that the pandemic has had on oncology clinical trials. It will assess the effect of the COVID-19 situation on the initial presentation and investigation of patients with suspected cancer. It will also review the impact of the pandemic on the subsequent management of cancer patients, and how clinical trial approval, recruitment, and conduct were affected during the pandemic. An intriguing aspect of the pandemic is that clinical trials investigating treatments for COVID-19 and vaccinations against the causative virus, SARS-CoV-2, have been approved and conducted at an unprecedented speed. In light of this, this review will also discuss the potential that this enhanced regulatory environment could have on the running of oncology clinical trials in the future.
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Outcomes for patients with hematologic malignancy infected with COVID-19 have not been aggregated. The objective of this study was to perform a systematic review and meta-analysis to estimate the risk of death and other important outcomes for these patients. We searched PubMed and EMBASE up to 20 August 2020 to identify reports of patients with hematologic malignancy and COVID-19. The primary outcome was a pooled mortality estimate, considering all patients and only hospitalized patients. Secondary outcomes included risk of intensive care unit admission and ventilation in hospitalized patients. Subgroup analyses included mortality stratified by age, treatment status, and malignancy subtype. Pooled prevalence, risk ratios (RRs), and 95% confidence intervals (CIs) were calculated using a random-effects model. Thirty-four adult and 5 pediatric studies (3377 patients) from Asia, Europe, and North America were included (14 of 34 adult studies included only hospitalized patients). Risk of death among adult patients was 34% (95% CI, 28-39; N = 3240) in this sample of predominantly hospitalized patients. Patients aged ≥60 years had a significantly higher risk of death than patients <60 years (RR, 1.82; 95% CI, 1.45-2.27; N = 1169). The risk of death in pediatric patients was 4% (95% CI, 1-9; N = 102). RR of death comparing patients with recent systemic anticancer therapy to no treatment was 1.17 (95% CI, 0.83-1.64; N = 736). Adult patients with hematologic malignancy and COVID-19, especially hospitalized patients, have a high risk of dying. Patients ≥60 years have significantly higher mortality; pediatric patients appear to be relatively spared. Recent cancer treatment does not appear to significantly increase the risk of death.
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COVID-19/complicações , Neoplasias Hematológicas/mortalidade , Hospitalização/estatística & dados numéricos , Unidades de Terapia Intensiva/estatística & dados numéricos , SARS-CoV-2/isolamento & purificação , COVID-19/transmissão , COVID-19/virologia , Neoplasias Hematológicas/terapia , Neoplasias Hematológicas/virologia , Humanos , Prognóstico , Taxa de SobrevidaAssuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/etiologia , Coronavirus/patogenicidade , Neoplasias Hematológicas/fisiopatologia , Pneumonia Viral/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19 , História do Século XXI , Humanos , Pessoa de Meia-Idade , Pandemias , SARS-CoV-2RESUMO
There have been significant advances in our understanding of the pathogenesis of chronic lymphocytic leukemia (CLL) over the last decade, which has been accompanied by a rapid increase in treatment options. Inhibitors of BCRsignaling such as ibrutinib and idelalisib, and pro-apoptotic agents such as ABT- 199 have shown great promise in initial clinical trials and have been at the forefront of recent developments. However, despite the encouraging early data, these agents do not appear to represent a "cure" for CLL and mechanisms of resistance to these agents have already been identified. In light of these considerations there remains a need for alternative treatment strategies. Lenalidomide, a second-generation derivative of thalidomide, has been demonstrated to have significant clinical activity in CLL. Its effect appears to be mediated by reduction of CLL-cell proliferation, improvement of anti-tumor immune responses and reduction of pro-tumoral factors in the CLL microenvironment. This review discusses our current understanding of the mechanism of action of lenalidomide on both healthy cells and in CLL. It also summarises the published clinical trial experience with this drug, and proposes an ongoing role for this agent in the CLL armamentarium.
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Inibidores da Angiogênese/uso terapêutico , Antineoplásicos/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Talidomida/análogos & derivados , Proliferação de Células/efeitos dos fármacos , Humanos , Lenalidomida , Leucemia Linfocítica Crônica de Células B/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Receptores de Antígenos de Linfócitos B/metabolismo , Talidomida/uso terapêuticoRESUMO
T-cell defects, immune suppression, and poor antitumor immune responses are hallmarks of chronic lymphocytic leukemia (CLL), and PD-1/PD-L1 inhibitory signaling has emerged as a major immunosuppressive mechanism. However, the effect of different microenvironments and the confounding influence of aging are poorly understood. The current study uses the Eµ-TCL1 mouse model, which replicates human T-cell defects, as a preclinical platform to longitudinally examine patterns of T-cell dysfunction alongside developing CLL and in different microenvironments, with a focus on PD-1/PD-L1 interactions. The development of CLL was significantly associated with changes in T-cell phenotype across all organs and function. Although partly mirrored in aging wild-type mice, CLL-specific T-cell changes were identified. Murine CLL cells highly expressed PD-L1 and PD-L2 in all organs, with high PD-L1 expression in the spleen. CD3(+)CD8(+) T cells from leukemic and aging healthy mice highly expressed PD-1, identifying aging as a confounder, but adoptive transfer experiments demonstrated CLL-specific PD-1 induction. Direct comparisons of PD-1 expression and function between aging CLL mice and controls identified PD-1(+) T cells in CLL as a heterogeneous population with variable effector function. This is highly relevant for therapeutic targeting of CD8(+) T cells, showing the potential of reprogramming and selective subset expansion to restore antitumor immunity.
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Envelhecimento/imunologia , Antígeno B7-H1/fisiologia , Linfócitos T CD8-Positivos/imunologia , Leucemia Linfocítica Crônica de Células B/imunologia , Receptor de Morte Celular Programada 1/fisiologia , Envelhecimento/genética , Animais , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Células Cultivadas , Modelos Animais de Doenças , Cadeias mu de Imunoglobulina/genética , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/patologia , Camundongos , Camundongos Transgênicos , Proteínas Proto-Oncogênicas/genética , Transdução de Sinais/imunologiaRESUMO
Over the past decade, there have been significant advances in our understanding of the pathogenesis of chronic lymphocytic leukemia (CLL), which has been accompanied by an explosion in treatment options. Although the combination of fludarabine, cyclophosphamide, and rituximab is the current frontline treatment of choice for fit patients, targeted therapies such ibrutinib, idelalisib, and ABT-199 are showing great promise in clinical trials. However, none of these drugs seems curative, and allogeneic hematopoietic stem cell transplantation remains the only strategy that produces durable clinical remissions in otherwise poor-risk disease. Immune reconstitution remains an enticing prospect in CLL, as malignant B cells should be particularly susceptible to a T cell-mediated attack. It has recently been demonstrated that the T-cell defect in CLL can be effectively overcome by both lenalidomide treatment and by adoptive transfer of chimeric antigen receptor T cells. A variety of other immunotherapies are in development, including CLL vaccines, CD40 ligand therapies, and monoclonal antibody immune checkpoint blockade. This review explores the nature of the immune defect in CLL and summarizes the recent developments in the immunotherapeutic field.
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Fatores Imunológicos/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Anticorpos Monoclonais/uso terapêutico , Ligante de CD40/uso terapêutico , Vacinas Anticâncer/imunologia , Humanos , Imunoterapia , Lenalidomida , Leucemia Linfocítica Crônica de Células B/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Talidomida/análogos & derivados , Talidomida/uso terapêuticoRESUMO
The leukocyte adhesion cascade is important in chronic lymphocytic leukemia (CLL), as it controls migration of malignant cells into the pro-survival lymph node microenvironment. Circulating trisomy 12 CLL cells have increased expression of the integrins CD11a and CD49d, as well as CD38, but the tissue expression of these and other molecules, and the functional and clinical sequelae of these changes have not been described. Here, we demonstrate that circulating trisomy 12 CLL cells also have increased expression of the integrins CD11b, CD18, CD29, and ITGB7, and the adhesion molecule CD323. Notably, there was reduced expression of CD11a, CD11b, and CD18 in trisomy 12 cases with NOTCH1 mutations compared with wild type. Trisomy 12 cells also exhibit upregulation of intracellular integrin signaling molecules CALDAG-GEFI, RAP1B, and Ras-related protein ligand, resulting in enhanced very late antigen-4 [VLA-4] directed adhesion and motility. CD38 expression in CLL has prognostic significance, but the increased CD38 expression in trisomy 12 CLL cells must be taken into account in this subgroup, and the threshold of CD38 positivity should be raised to 40% for this marker to retain its prognostic value. In conclusion, trisomy 12 CLL cells exhibit functional upregulation of integrin signaling, with ß2-integrin expression being modulated by NOTCH1 mutation status.
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Regulação Leucêmica da Expressão Gênica , Integrinas/biossíntese , Leucemia Linfocítica Crônica de Células B/metabolismo , Mutação , Proteínas de Neoplasias/metabolismo , Células Neoplásicas Circulantes/metabolismo , Receptor Notch1/metabolismo , Transdução de Sinais , Regulação para Cima , Idoso , Movimento Celular/genética , Cromossomos Humanos Par 12/genética , Cromossomos Humanos Par 12/metabolismo , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Humanos , Integrinas/genética , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Células Neoplásicas Circulantes/patologia , Receptor Notch1/genética , Trissomia/genética , Trissomia/patologia , Proteínas rap de Ligação ao GTP/genética , Proteínas rap de Ligação ao GTP/metabolismoRESUMO
In this issue of Blood, te Raa et al report that cytomegalovirus (CMV)-specific CD8+ T-cell function is preserved in chronic lymphocytic leukemia (CLL), on a background of global T-cell dysfunction.