Current Hematologic Malignancy Reports最新文献

Purpose of review: Myelofibrosis (MF) is a myeloproliferative neoplasm characterized by bone marrow fibrosis, megakaryocyte atypia, and inflammatory cytokine overproduction, resulting in progressive cytopenias, splenomegaly, and high symptom burden. Current backbone of care includes JAK inhibitor (JAKi) therapy, which offers limited benefits and significant discontinuation rates. Targeting the epigenetic modifiers bromodomain and extra-terminal domain (BET) proteins is a novel approach for harnessing the expression of genes involved in critical oncogenic signalling pathways implicated in MF and other malignancies. Here, we review preclinical and clinical data on Pelabresib (CPI-0610), an investigational oral small-molecule potent BET-inhibitor being explored in MF.

Recent findings: BET inhibition has been shown to target multiple MF driver mechanisms in preclinical studies, with synergistic results using combination therapy with JAKi. Pelabresib is currently being evaluated in the phase II MANIFEST study as monotherapy and in combination with ruxolitinib for MF. Interim data showed favourable responses in symptoms and spleen volume after 24 weeks of treatment, with correlated improvements in bone marrow fibrosis and mutant allele fraction reduction. Based on these encouraging results, the Phase III MANIFEST-2 study was initiated. Pelabresib offers a much-needed innovative treatment approach for patients with MF, either as monotherapy or in combination with the current standard of care.

Purpose of review: This review focuses on vascular complications associated with chronic myeloproliferative neoplasms (MPN) and more specifically aims to discuss the clinical and biological evidence supporting the existence of a link between clonal hematopoiesis, cardiovascular events (CVE), and solid cancer (SC).

Recent findings: The MPN natural history is driven by uncontrolled clonal myeloproliferation sustained by acquired somatic mutations in driver (JAK2, CALR, and MPL) and non-driver genes, involving epigenetic (e.g., TET2, DNMT3A) regulators, chromatin regulator genes (e.g., ASXL1, EZH2), and splicing machinery genes (e.g., SF3B1). The genomic alterations and additional thrombosis acquired risk factors are determinants for CVE. There is evidence that clonal hematopoiesis can elicit a chronic and systemic inflammation status that acts as driving force for the development of thrombosis, MPN evolution, and second cancer (SC). This notion may explain the mechanism that links arterial thrombosis in MPN patients and subsequent solid tumors. In the last decade, clonal hematopoiesis of indeterminate potential (CHIP) has been detected in the general population particularly in the elderly and initially found in myocardial infarction and stroke, rising the hypothesis that the inflammatory status CHIP-associated could confer predisposition to both cardiovascular diseases and cancer. In summary, clonal hematopoiesis in MPN and CHIP confer a predisposition to cardiovascular events and cancer through chronic and systemic inflammation. This acquisition could open new avenues for antithrombotic therapy both in MPNs and in general population by targeting both clonal hematopoiesis and inflammation.

Purpose of review: Long-term outcomes have significantly improved with treatment of chronic myeloid leukemia. With proper treatment, most patients will achieve similar survival rates compared to an age-matched population. Treatment-free remission is not attainable for over half of patients and chronic treatment carries with it unique challenges. We provide a pragmatic approach to the monitoring and management of chronic adverse effects (AEs).

Recent findings: In the presence of severe or intolerable AEs, switching tyrosine kinase inhibitors (TKIs) is reasonable but is not without risk. Dose reductions can be attempted when response is stable to reduce AE intensity. More frequent molecular monitoring with any change is essential. Treatment strategies must adapt to the personalized treatment goal of each patient. Long-term survival remains good even when response is less than a complete molecular response. Consider risks of new AEs when changing therapy and evaluate for dose reductions when appropriate.

Purpose of review: GATA2 deficiency is a haploinsufficiency syndrome associated with a wide spectrum of disease, including severe monocytopenia and B and NK lymphopenia, predisposition to myeloid malignancies, human papillomavirus infections, and infections with opportunistic organisms, particularly nontuberculous mycobacteria, herpes virus, and certain fungi. GATA2 mutations have variable penetrance and expressivity with imperfect genotype-phenotype correlations. However, approximately 75% of patients will develop a myeloid neoplasm at some point. Allogeneic hematopoietic cell transplantation (HCT) is the only currently available curative therapy. Here, we review the clinical manifestations of GATA2 deficiency, characterization of the hematologic abnormalities and progression to myeloid malignancy, and current HCT practices and outcomes.

Recent findings: Cytogenetic abnormalities are common with high rates of trisomy 8, monosomy 7, and unbalanced translocation der(1;7) and may suggest an underlying GATA2 deficiency in patients presenting with myelodysplastic syndrome (MDS). Mutations in ASXL1 and STAG2 are the most frequently encountered somatic mutations and are associated with lower survival probability. A recent report of 59 patients with GATA2 deficiency who underwent allogenic HCT with myeloablative, busulfan-based conditioning and post-transplant cyclophosphamide reported excellent overall and event-free survival of 85% and 82% with reversal of disease phenotype and low rates of graft versus host disease. Allogeneic HCT with myeloablative conditioning results in disease correction and should be considered for patients with a history of recurrent, disfiguring and/or severe infections, organ dysfunction, MDS with cytogenetic abnormalities, high-risk somatic mutations or transfusion dependence, or myeloid progression. Improved genotype/phenotype correlations are needed to allow for greater predictive capabilities.

Purpose of review: To discuss novel targeted therapies under investigation for treatment of myelodysplastic neoplasms (MDS).

Recent findings: Over the last few years, results of phase 3 trials assessing novel therapies for high-risk MDS have been largely disappointing. Pevonedistat (NEDD-8 inhibitor) and APR-246 (TP53 reactivator) both did not meet trial endpoints. However, early phase trials of BCL-2, TIM3, and CD47 inhibitors have shown exciting data and are currently under phase 3 investigation. Moreover, combination of hypomethylating agents (HMA) with novel therapies targeting the mutational (IDH, FLT3, spliceosome complex) or immune (PD-1/PDL-1, TIM-3, IRAK-4) pathways are being investigated in early phase clinical trials and have shown adequate safety and promising efficacy. Myelodysplastic neoplasms (MDS) are a group of hematopoietic neoplasms defined by cytopenias and morphological dysplasia. They are characterized by clonal proliferation of aberrant hematopoietic stem cells caused by recurrent genetic abnormalities. This leads to ineffective erythropoiesis, peripheral blood cytopenias, abnormal cell maturation, and a high risk of transformation into acute myeloid leukemia (AML). Allogeneic hematopoietic stem cell transplantation is the only curative therapy; however, it is not a suitable option for majority patients due to their age, comorbidities, and the high rate of treatment-related complications. HMAs remain the only FDA-approved treatment option for high-risk MDS. Due to intolerance, primary, and secondary resistance to HMA, there is a large unmet need to develop new safe and effective therapies for patients with MDS. In this review, we focus on the current management strategies and novel therapies in development for treatment of high-risk MDS.

Purpose of review: JAK inhibition is an effective means of controlling symptom burden and improving splenomegaly in patients with myeloproliferative neoplasms (MPNs). However, a majority of patients treated with JAK inhibition will have disease progression with long-term use. In In this review, we focus on the investigation of novel targeted agents beyond JAK inhibitors both in the chronic phase of disease and in the accelerated/blast phase of disease.

Recent findings: Relevant targeted therapies in MPNs include BET inhibitors, BCL inhibitors, LSD1 inhibitors, PI3K inhibitors, IDH inhibitors, telomerase inhibitors, and MDM2 inhibitor. Agents within these classes have been investigated either as monotherapy or in combination with a JAK inhibitor. We summarize the prospective data for these agents along with detailing the ongoing phase III trials incorporating these agents. While JAK inhibition has been a mainstay of therapy in MPNs, a majority of patients will have disease of progression. JAK inhibitors also have limited anti-clonal effect and do not impact the rate of progression to the blast phase of disease. The novel therapies detailed in this review not only show promise in ameliorating the symptom burden of MPNs but may be able to alter the natural history of disease.

Purpose of review: With improvement in survival after hematopoietic cell transplantation (HCT), it has become important to focus on the late complications experienced by the survivors that may lead to late mortality and morbidity to be able to provide patient-centered care across the transplant continuum. The goals of this article are to describe the status of literature on late complications in HCT survivors; offer a brief overview of the status of the screening, prevention, and management of these complications; and identify opportunities for future practice and research.

Recent findings: This is an exciting time for the field with increasing awareness about survivorship issues. Studies are moving beyond description to examining pathogenesis of these late complications and identifying biomarkers. The eventual goal is to promote changes in our transplant techniques to decrease the incidence of these complications as well as help develop interventions targeting these late effects. There is also an emphasis on improving health care delivery models to provide optimal post-HCT management for medical and psychosocial complications through close coordination between multiple stakeholders and leveraging technology to help address the barriers in delivery of care to fulfill the unmet needs in this area. The increasing population of HCT survivors with their burden of late effects underscores the need for concerted efforts to improve long-term medical and psychosocial outcomes for this group.

Purpose of review: Despite progress in the treatment of pediatric B-cell acute lymphoblastic leukemia (ALL) and PH + ALL, fewer advancements have been for older adults with PH-negative B-cell ALL. Treatment of this population is mired by higher incidence of poor risk biologic features, increased incidence of medical comorbidities, and higher rates of treatment-related mortality (TRM). Here, we review the difficulties in managing elderly patients with PH-negative ALL.

Recent findings: The development of novel agents has brought additional tools to the armamentarium of drugs and has changed the landscape of treatment. More recent clinical trials and future clinical trials focus on blinatumomab, inotuzomab ozogamicin (IO), and/or chimeric antigen receptor T-cell (CAR-T) either alone or integrated with dose-reduced chemotherapy regimens. The introduction of novel agents/therapies and incorporation into our current treatment paradigms may finally offer an avenue to improve the dismal outcomes seen in this population.

Purpose of review: Cutaneous T cell lymphomas (CTCLs) exhibit a wide variety of clinical features, histologic characteristics, and genetic drivers. We review novel molecular findings that inform our understanding of the pathogenesis of CTCL, with a focus on the tumor microenvironment (TME).

Recent findings: There is increasing evidence challenging the model of T_CM:mycosis fungoides (MF) and T_EM:Sézary syndrome (SS) phenotype. Phylogenetic analysis performed using whole-exome sequencing (WES) raises the possibility that MF can arise without a common ancestral T cell clone. The detection of ultraviolet (UV) marker signature 7 mutations in the blood of patients with SS raises questions about the role of UV exposure in CTCL pathogenesis. There is also increasing interest on the role of the TME in CTCL. Existing therapies such as the RXR retinoid bexarotene and the anti-CCR4 monoclonal antibody mogamulizumab may act through the CTCL TME by impacting the CCL22:CCR4 axis, while cancer-associated fibroblasts (CAFs) in the CTCL TME contribute to drug resistance, as well as a Th2 milieu and tumor growth via secretion of pro-tumorigenic cytokines. Staphylococcus aureus (SA) is a frequent cause of morbidity among CTCL patients. SA may positively select for malignant T cells through adaptive downregulation of alpha-toxin surface receptors and promotion of tumor growth via upregulation of the JAK/STAT pathway. Recent molecular advancements have contributed to our understanding of the pathogenesis of CTCL and shed light into the potential mechanisms of existing therapies. Further understanding of the CTCL TME may fuel the discovery of novel therapies for CTCL.

Purpose of review: Tyrosine kinase inhibitors (TKIs) are very successful for the treatment of chronic myeloid leukaemia (CML) but are not curative in most patients due to persistence of TKI-resistant leukaemia stem cells (LSCs). The bone marrow immune microenvironment (BME) provides protection to the LSC through multidimensional interactions, driving therapy resistance, and highlighting the need to circumvent these protective niches therapeutically. This review updates the evidence for interactions between CML cells and the immune microenvironment with a view to identifying targetable therapeutic vulnerabilities and describes what is known about the role of immune regulation in treatment-free remission (TFR).

Recent findings: Intracellular signalling downstream of the chemotactic CXCL12-CXCR4 axis, responsible for disrupted homing in CML, has been elucidated in LSCs, highlighting novel therapeutic opportunities. In addition, LSCs expressing CXCL12-cleaving surface protein CD26 were highly correlated with CML burden, building on existing evidence. Newer findings implicate the adhesion molecule CD44 in TKI resistance, while JAK/STAT-mediated resistance to TKIs may occur downstream of extrinsic signalling in the BME. Exosomal BME-LSC cross-communication has also been explored. Finally, further detail on the phenotypes of natural killer (NK) cells putatively involved in maintaining successful TFR has been published, and NK-based immunotherapies are discussed. Recent studies highlight and build on our understanding of the BME in CML persistence and TKI resistance, pinpointing therapeutically vulnerable interactions. Repurposing existing drugs and/or the development of novel inhibitors targeting these relationships may help to overcome these issues in TKI-resistant CML and be used as adjuvant therapy for sustained TFR.