Search Results (111)

Chronic lymphocytic leukemia (CLL) is the most common leukemia in adults. It is characterized by the clonal proliferation of mature B cells. The tumor microenvironment (TME) seems to play a crucial role in the survival and proliferation of tumor cells. Multiple new classes of drugs had been approved for the management of patients with CLL, reshaping the treatment paradigm. The most important classes are Bruton’s tyrosine kinase (BTK) inhibitors and BCL-2 inhibitors. Both of them are approved as a first-line treatment in patients with CLL requiring treatment. The role of BTK and BCL-2 in the signaling pathways of the TME is very important. The aim of this review is to summarize the major components of the TME and the available data regarding targeted therapies in CLL. Full article

Bruton Tyrosine Kinase (BTK) has emerged as a critical mediator in the pathophysiology of neuroinflammation associated with neurodegenerative diseases. BTK, a non-receptor tyrosine kinase predominantly expressed in cells of the hematopoietic lineage, modulates B-cell receptor signaling and innate immune responses, including microglial activation. Recent evidence implicates aberrant BTK signaling in the exacerbation of neuroinflammatory cascades contributing to neuronal damage in disorders such as Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, ischemic stroke, and Huntington’s disease. Pharmacological inhibition of BTK has shown promise in attenuating microglial-mediated neurotoxicity, reducing pro-inflammatory cytokine release, and promoting neuroprotection in preclinical models. BTK inhibitors, originally developed for hematological malignancies, demonstrate favorable blood–brain barrier penetration and immunomodulatory effects relevant to central nervous system pathology. This therapeutic approach may counteract detrimental neuroimmune interactions without broadly suppressing systemic immunity, thus preserving host defense. Ongoing clinical trials are evaluating the safety and efficacy of BTK inhibitors in patients with neurodegenerative conditions, with preliminary results indicating potential benefits in slowing disease progression and improving neurological outcomes. This review consolidates current knowledge on BTK signaling in neurodegeneration and highlights the rationale for BTK inhibition as a novel, targeted therapeutic strategy to modulate neuroinflammation and mitigate neurodegenerative processes. Full article

Pediatric-onset multiple sclerosis (POMS) is a rare yet increasingly recognized demyelinating disease of the central nervous system, characterized by a highly inflammatory disease course and an elevated relapse rate compared to adult-onset MS (AOMS). Given the unique immunopathogenesis of POMS, recent therapeutic strategies have shifted toward early initiation of high-efficacy disease-modifying therapies (DMTs) to minimize irreversible neurological damage. Among these, B-cell-targeting therapies, particularly anti-CD20 monoclonal antibodies, have shown efficacy in adult MS and are emerging as promising candidates for POMS treatment. The present review summarizes the current knowledge of the role of B-cells in POMS pathophysiology and evaluates the therapeutic potential of anti-CD-20 agents. It also highlights ongoing clinical trials and future perspectives, including novel B-cell-directed approaches such as anti-CD19 therapies, Bruton’s tyrosine kinase (BTK) inhibitors, and BAFF-targeting agents. Full article

Chronic Lymphocytic Leukemia (CLL) is a highly heterogeneous tumor. Although targeted therapies such as Bruton’s Tyrosine Kinase (BTK) inhibitors and B-cell lymphoma-2 (Bcl-2) inhibitors have significantly improved patient outcomes in CLL, the disease remains incurable. A critical aspect of CLL progression is its transformation from an indolent tumor to a high-grade malignancy, a process known as Richter’s Transformation (RT) or Richter Syndrome. Treatment options for RT are very limited, and patient prognosis is often poor. The molecular mechanisms driving RT are not yet fully elucidated. This review aims to summarize recent advances in research aimed at uncovering the mechanisms underlying RT in CLL. By integrating findings from genetics, signaling pathways, epigenetics, and the tumor microenvironment, this review seeks to provide insights that could guide further basic research into RT and inform the development of novel therapeutic strategies to improve patient outcomes. Full article

Bruton’s tyrosine kinase (BTK) is a key signaling molecule involved in both hematological malignancies and solid tumors. In B-cell malignancies such as chronic lymphocytic leukemia (CLL) and non-Hodgkin lymphoma (NHL), BTK mediates B-cell receptor signaling, promoting tumor survival and proliferation, leading to the development of BTK inhibitors like ibrutinib that improve patient outcomes. In solid tumors, BTK isoforms, particularly p65BTK, contribute to tumor growth and therapy resistance, with inhibition showing promise in cancers like colorectal, ovarian, and non-small cell lung cancer. BTK also influences the tumor microenvironment by modulating immune cells such as myeloid-derived suppressor cells and tumor-associated macrophages, aiding immune evasion. BTK inhibition can enhance anti-tumor immunity and reduce inflammation-driven tumor progression. Additionally, BTK contributes to tumor angiogenesis, with inhibitors like ibrutinib showing anti-angiogenic effects. Beyond cancer, BTK is linked to aging, where its modulation may reduce senescent cell accumulation and preserve cognitive function. This review explores BTK’s dual role, focusing on its oncogenic effects and potential impact on aging processes. We also discuss the use of BTK inhibitors in cancer treatment and their potential to address age-related concerns, providing a deeper understanding of BTK as a therapeutic target and mediator in the complex relationship between cancer and aging. Full article

Multiple sclerosis (MS) is an autoimmune demyelinating disease of the central nervous system. The therapeutic landscape for MS has evolved significantly since the 1990s, with the development of more than 20 different disease-modifying therapies (DMTs). These therapies effectively manage relapses and inflammation, but most have failed to meaningfully prevent disease progression. While classically understood as a T cell-mediated condition, the most effective DMTs in slowing progression also target B cells. Novel classes of MS therapies in development, including anti-CD40L monoclonal antibodies, CD19 chimeric antigen receptor (CAR) T cells, and Bruton’s tyrosine kinase (BTK) inhibitors show greater capacity to target and eliminate B cells in the brain/CNS, as well as impacting T-cell and innate immune compartments. These approaches may help tackle the disease at its immunopathological core, addressing both peripheral and central immune responses that drive MS progression. Another emerging therapeutic strategy is to use bispecific antibodies, which have the potential for dual-targeting various disease aspects such as immune activation and neurodegeneration. As such, the next generation of MS therapies may be the first to reduce both inflammatory demyelination and disease progression in a clinically meaningful way. Their ability to target specific immune cell populations while minimizing broad immune suppression could also lead to better safety profiles. Here, we explore the biological rationale, advantages, limitations, and clinical progress of these emerging immunotherapies for relapsing–remitting and progressive forms of MS. Full article

Effective available treatment options for patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) who relapse after becoming refractory to both a covalent Bruton Tyrosine Kinase inhibitor (cBTKi) and a B cell leukemia/lymphoma 2 inhibitor (BCL2i) remain limited, and prognosis is very poor. Emerging areas of drug development include cellular therapies such as chimeric antigen receptor T-cell therapy and bispecific antibodies. However, cost, accessibility, toxicity, and the need for either prolonged or repeated hospitalization prevent universal application of these therapies. Given this area of unmet clinical need, we present this review article on Bruton Tyrosine Kinase (BTK) degraders in patients with CLL/SLL. We focus on their development as a drug class, the up-to-date clinical data available, as well as future directions. BTK protein degraders are a novel drug class with an alternate mechanism of action (MOA), compared to cBTKis and non-covalent BTKis (ncBTKis), causing ubiquitination of BTK, thereby leading to its degradation through the proteasome. Encouraging pre-clinical data show that this MOA allows BTK protein degraders to overcome common BTK mutations. We focus on four agents which are under investigation in B-cell malignancies in early clinical trials: BGB-16673, NX-2127, NX-5948, and AC676. Preliminary data suggest a comparable safety and toxicity profile between agents across this drug class with many patients on phase 1 trials deriving durable clinical benefit. Optimal sequencing of BTK degraders in the therapeutic landscape of CLL/SLL treatment is yet to be established. Further trials investigating these agents in combination with other targeted CLL agents may help to further understand their applicability. An effective, tolerable oral class of drugs would be invaluable in the treatment of patients with multiply relapsed CLL/SLL. Full article

Pathway inhibitors targeting Bruton tyrosine kinase (BTK) and B-cell lymphoma-2 (BCL-2) have dramatically changed the treatment landscape for both treatment-naïve and relapsed/refractory chronic lymphocytic leukemia (CLL). However, with increased utilization, a growing number of patients will experience progressive disease on both agents. This subgroup of “double refractory” patients has limited treatment options and poor prognosis. Chimeric antigen receptor (CAR)-T cells have transformed the treatment of relapsed/refractory B-cell malignancies. Although the earliest success of CAR-T cell therapy was in CLL, the clinical application of this modality has lagged until the recent approval of the first CAR-T cell product for CLL. In this review, we describe the current treatment options for upfront and subsequent therapies and the unmet need for novel agents highlighted by the burgeoning role and challenges of CAR-T cell therapy. Full article

Chronic lymphocytic leukemia (CLL) treatment has undergone a significant evolution with a shift from historical chemotherapeutic regimens to targeted therapies such as Bruton tyrosine kinase (BTK) and BCL-2 inhibitors. These advancements have been associated with a notable improvement in survival rates with a transformation of CLL into a chronic and manageable condition for most persons with this disease. However, as a consequence of improved outcomes, long-term CLL survivors now face emergent challenges which include a risk of infections, cardiovascular complications, and secondary malignancies. In this changed scenario, holistic models of care are essential to address emergent health risks. Such models of care for CLL patients require a multidisciplinary approach that integrates CLL treatment with the proactive management of frailty, comorbidities, and psychosocial well-being to enhance both survival and quality of life (QoL). CLL predominantly affects older persons, many of whom present with concurrent frailty and comorbidities that may complicate CLL treatment and impact QoL. Comprehensive geriatric assessments (GA) may play a critical role in the identification of persons at a heightened risk of treatment-related toxicity and may help guide rational therapy selection, particularly in very frail persons. In addition to the assessment of hematological responses, the prospective assessment of patient-reported outcomes (PROs) and frailty metrics may offer a more nuanced understanding of the global treatment benefits. A survivorship-focused care model is crucial to address the multifaceted needs of CLL patients with the extension of patient care into the broader domain of long-term health maintenance with associated improvements in QoL. Full article

Background: Chronic lymphocytic leukaemia (CLL) is the most common form of leukaemia among adults, particularly in Western nations. The introduction of Bruton’s tyrosine kinase (BTK) inhibitors as a treatment of CLL, namely, ibrutinib, which is a first-generation BTK inhibitor, has significantly improved the treatment landscape for CLL. However, ibrutinib has been associated with an increased risk of atrial fibrillation (AF) and hypertension. Real-world studies that compare the cardiovascular safety of ibrutinib with bendamustine plus anti-CD20 monoclonal antibody are not widely available. Methods: A retrospective cohort analysis using the TriNetX platform identified two patient groups: one treated with ibrutinib and the other with bendamustine and an anti-CD20 antibody. Propensity score matching balanced their demographic and clinical characteristics. The outcomes evaluated included the all-cause mortality and new-onset AF/flutter, hypertension, heart failure, ventricular arrhythmias, and bleeding. Results: No significant difference was observed in the all-cause mortality between the two cohorts. However, ibrutinib was associated with a higher risk of AF/flutter (HR 1.89, 95% CI 1.36–2.62; p < 0.05) and hypertension (HR 1.22, 95% CI 1.01–1.47; p = 0.04). Other outcomes, such as heart failure, ventricular arrhythmias, and bleeding, were not different between the cohorts. Conclusions: Ibrutinib remains a valuable option for the treatment of CLL, but is associated with significant cardiovascular risks, leading to it being superseded by the newer generation of BTKis, which offer less cardiovascular toxicities. These results highlight the TriNetX platform’s reliability as a real-world data source for validating clinical trial findings and highlight the importance of incorporating cardio-oncology into treatment plans for CLL patients with significant comorbidities. Full article

Chronic lymphocytic leukemia (CLL) is characterized by the accumulation of B cells due to constitutive B-cell receptor (BCR) signaling, leading to apoptosis resistance and increased proliferation. This study evaluates the effects of the Bruton Tyrosine Kinase (BTK) inhibitor ibrutinib on the molecular composition, clonality, and kinetics of B cells during treatment in CLL patients. Employing a multi-omics approach of up to 3.2 years of follow-up, we analyzed data from 24 CLL patients, specifically focusing on nine patients treated with ibrutinib monotherapy. In this study, clonal stability was observed within the ibrutinib-treated group following an effective initial clinical response, where clonotype frequencies of residual CLL cells remained high and stable, ranging from 74.9% at 1.5 years to 87.7% at approximately 3 years. In contrast, patients treated with the B-cell lymphoma 2 (BCL2) inhibitor venetoclax exhibited substantial reductions in clonal frequencies, approaching molecular eradication. Deep whole-exome sequencing revealed minimal genomic progression in the ibrutinib group, maintaining somatic drivers and variant allele frequencies (VAF) above 0.2 throughout treatment. At the single-cell level, the NF-κB pathway inhibition and apoptotic signals were detected or even augmented during treatment in ibrutinib-treated patients. These findings may corroborate the role of ibrutinib in stabilizing the genomic landscape of CLL cells, preventing significant genomic evolution despite maintaining a high clonal burden within the residual B-cell compartment. Full article

Overexpression of the anti-apoptotic protein BCL-2 is a key factor in the pathogenesis of chronic lymphocytic leukemia (CLL) and is associated with poor clinical outcomes. Therapeutic activation of apoptosis in cancer cells using the BCL-2 inhibitor (BCL2i) venetoclax has shown remarkable efficacy in clinical trials, both as monotherapy and combination regimens. However, patients with CLL experience a highly variable clinical course, facing significant challenges in advanced stages due to disease relapse and the emergence of resistant clones. Resistance mechanisms include acquired BCL-2 mutations, alteration of pro-apoptotic and anti-apoptotic proteins, metabolic reprogramming, epigenetic changes, and aberrant signaling pathways. To address this complex disease and improve progression-free survival, strategies targeting multiple signaling pathways and mechanisms have been explored. Randomized clinical trials of venetoclax in combination with Bruton tyrosine kinase (BTK) inhibitors or CD20 monoclonal antibodies have significantly outperformed traditional chemoimmunotherapy in both treatment-naïve and relapsed patients, achieving undetectable minimal residual disease (uMRD) and durable remissions. This review explores the intricate balance between BCL-2 family proteins and their role in the intrinsic apoptosis pathway, discusses venetoclax resistance mechanisms, and highlights the evolving role of venetoclax and other BCL2i-based combination therapies in CLL treatment. Full article

Bruton’s tyrosine kinase (BTK), a cytoplasmic tyrosine kinase, plays a pivotal role in B cell biology and function. As an essential component of the B cell receptor (BCR) signaling pathway, BTK is expressed not only in B cells but also in myeloid cells, including monocytes/macrophages, dendritic cells, neutrophils, and mast cells. BTK inhibitors (BTKis) have revolutionized the treatment of chronic lymphocytic leukemia (CLL) and other B cell malignancies. Besides their well-characterized role in inhibiting BCR signaling, BTKis also exert significant immunological influences outside the tumor cell that extend their therapeutic potential and impact on the immune system in different ways. This work elucidates the immunomodulatory mechanisms associated with BTK inhibition, focusing on CLL and other clinical contexts. We discuss how BTK inhibition affects various immune cells, including B cells, T cells, and macrophages. The effects of BTKis on the profiles of cytokines, also fundamental parts of the tumor microenvironment (TME), are summarized here as well. This review also appraises the implications of these immunomodulatory actions in the management of autoimmune diseases and infections. Summarizing the dual role of BTK inhibition in modulating malignant lymphocyte and immune cell functions, this paper highlights the broader potential clinical use of compounds targeting BTK. Full article

B-cell lymphoid malignancies are a heterogeneous group of hematologic cancers, where Bruton’s tyrosine kinase (BTK) inhibitors have received FDA approval for several subtypes. The first-in-class covalent BTK inhibitor, Ibrutinib, binds to the C481 amino acid residue to block the BTK enzyme and prevent the downstream signaling. Resistance to covalent BTK inhibitors (BTKi) can occur through mutations at the BTK binding site (C481S) but also other BTK sites and the phospholipase C gamma 2 (PLCγ2) resulting in downstream signaling. To bypass the C481S mutation, non-covalent BTKi, such as Pirtobrutinib, were developed and are active against both wild-type and the C481S mutation. In this review, we discuss the molecular and genetic mechanisms which contribute to acquisition of resistance to covalent and non-covalent BTKi. In addition, we discuss the new emerging class of BTK degraders, which utilize the evolution of proteolysis-targeting chimeras (PROTACs) to degrade the BTK protein and constitute an important avenue of overcoming resistance. The moving landscape of resistance to BTKi and the development of new therapeutic strategies highlight the ongoing advances being made towards the pursuit of a cure for B-cell lymphoid malignancies. Full article

Chronic lymphocytic leukemia (CLL) is a B-cell-derived hematologic malignancy whose progression depends on active B-cell receptor (BCR) signaling. Despite the spectacular efficacy of Ibrutinib, an irreversible inhibitor of Bruton tyrosine kinase (BTK), resistance can develop in CLL patients, and alternative therapeutic strategies are therefore required. Cancer immunotherapy has revolutionized cancer care and may be an attractive approach in this context. We speculated that characterizing the immune responses of CLL patients may highlight putative immunotherapeutic targets. Here, we used high-dimensional spectral flow cytometry to compare the distribution and phenotype of non-B-cell immune populations in the circulating blood of CLL patients treated with Ibrutinib displaying a complete response or secondary progression. Although no drastic changes were observed in the composition of their immune subsets, the Ibrutinib-resistant group showed increased cycling of CD8+ T cells, leading to their overabundance at the expense of dendritic cells. In addition, the expression of 11 different surface checkpoints was similar regardless of response status. Together, this suggests that CLL relapse upon Ibrutinib treatment may not lead to major alterations in the peripheral immune response. Full article