Addition of Navitoclax to Ongoing Ruxolitinib Therapy for Patients With Myelofibrosis With Progression or Suboptimal Response: Phase II Safety and Efficacy

Targeted Therapies in Myelofibrosis: Present Landscape, Ongoing Studies, and Future Perspectives

Myelofibrosis (MF) is a myeloproliferative neoplasm that is accompanied by driver JAK2, CALR, or MPL mutations in more than 90% of cases, leading to constitutive activation of the JAK-STAT pathway. MF is a multifaceted disease characterized by trilineage myeloid proliferation with prominent megakaryocyte atypia and bone marrow fibrosis, as well as splenomegaly, constitutional symptoms, ineffective erythropoiesis, extramedullary hematopoiesis, and a risk of leukemic progression and shortened survival. Therapy can range from observation alone in lower-risk and asymptomatic patients to allogeneic hematopoietic stem cell transplantation, which is the only potentially curative treatment capable of prolonging survival, although burdened by significant morbidity and mortality. The discovery of the JAK2 V617F mutation prompted the development of JAK inhibitors (JAKi) including the first-in-class JAK1/JAK2 inhibitor ruxolitinib and subsequent approval of fedratinib, pacritinib, and momelotinib. The latter has shown erythropoietic benefits by suppressing hepcidin expression via activin A receptor type 1 (ACVR1) inhibition, as well as reducing splenomegaly and symptoms. However, the current JAKi behave as anti-inflammatory drugs without a major impact on survival or disease progression. A better understanding of the genetics, mechanisms of fibrosis, cytopenia, and the role of inflammatory cytokines has led to the development of numerous therapeutic agents that target epigenetic regulation, signaling, telomerase, cell cycle, and apoptosis, nuclear export, and pro-fibrotic cytokines. Selective JAK2 V617F inhibitors and targeting of mutant CALR by immunotherapy are the most intriguing and promising approaches. This review focuses on approved and experimental treatments for MF, highlighting their biological background.

Basic and applied research progress of TRAIL in hematologic malignancies

Hematological malignancies encompass a diverse range of blood-related cancers characterized by abnormal blood cell production. These cancers, classified by the World Health Organization based on lineage, cell origin, and progression, provide a more comprehensive framework for understanding cancer biology. This classification has significantly advanced cancer research, particularly in genetic analyses for diagnosis and treatment. Despite recent clinical improvements, challenges, such as relapse, resistance, and high mortality, remain unresolved. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a protein that induces apoptosis in cancer cells without affecting normal cells, has emerged as a promising therapeutic target. However, its clinical efficacy is limited by factors, such as tumor heterogeneity and resistance to TRAIL signaling. This review examines the mechanisms of TRAIL in hematological malignancies, factors contributing to resistance, and the current state of preclinical and clinical research, highlighting potential strategies to enhance TRAIL-based therapies in blood cancers.

Vascular senescence and aging: mechanisms, clinical implications, and therapeutic prospects

The aging vasculature is characterized by endothelial dysfunction, arterial stiffness, and increased susceptibility to vascular pathologies. Central to these changes is the process of cellular senescence, where endothelial and vascular smooth muscle cells lose their replicative and functional capacity and adopt a pro-inflammatory secretory phenotype. This review provides an overview of the key mechanisms underlying vascular senescence, including the p53/p21 and p16/Rb pathways, the senescence-associated secretory phenotype (SASP), and oxidative stress, examines its contribution to cardiovascular diseases in older adults, and highlights emerging therapeutic strategies aimed at delaying or reversing these age-related vascular changes. In vascular cells, DNA damage, oxidative stress, and chronic inflammation associated with aging converge to amplify senescence. Clinically, vascular senescence is linked with hypertension, atherosclerosis, and increased overall cardiovascular risk. Several interventions, ranging from senolytics to lifestyle factors, show promise in mitigating these changes; however, long-term studies are needed. Given that vascular senescence is a pivotal driver of cardiovascular pathology in aging, targeting senescent cells or their secretory phenotype may potentially offer new avenues for preventing or attenuating age-related vascular diseases. This review presents an updated and integrative overview of vascular senescence, connecting fundamental cellular mechanisms with their clinical manifestations and highlighting the most promising therapeutic interventions.

Anti-senescence therapies: a new concept to address cardiovascular disease

Accumulation of senescent cells is an increasingly recognized factor in the development and progression of cardiovascular (CV) disease (CVD). Senescent cells of different types display a pro-inflammatory and matrix remodelling molecular programme, known as the 'senescence-associated secretory phenotype' (SASP), which has roots in (epi)genetic changes. Multiple therapeutic options (senolytics, anti-SASP senomorphics, and epigenetic reprogramming) that delete or ameliorate cellular senescence have recently emerged. Some drugs routinely used in the clinics also have anti-senescence effects. However, multiple challenges hinder the application of novel anti-senescence therapeutics in the clinical setting. Understanding the biology of cellular senescence, advantages and pitfalls of anti-senescence treatments, and patients who can profit from these interventions is necessary to introduce this novel therapeutic modality into the clinics. We provide a guide through the molecular machinery of senescent cells, systematize anti-senescence treatments, and propose a pathway towards senescence-adapted clinical trial design to aid future efforts.

A Critical Appraisal of the Utility of Targeting Therapy-Induced Senescence for Cancer Treatment

Cancer chemotherapy and radiotherapy are rarely successful in eliminating the entire tumor population, often leaving behind a subpopulation of senescent cells that can contribute to disease recurrence. These senescent tumor cells also secrete various chemokines and cytokines that may be tumor promoting and immunosuppressive. Recognition of the deleterious impact of therapy-induced senescence has led to the preclinical development of senolytic compounds that eliminate senescent cells, representing a potential strategy to enhance the efficacy of conventional and targeted anticancer therapy. However, it remains uncertain whether this strategy can or will be translated to the clinic. This review provides a summary of the recent preclinical literature supporting the use of senolytics as an adjunct for cancer treatment, discusses the limitations associated with their use in the current preclinical models, and provides perspectives on the clinical development of senolytics in cancer treatment regimens. Overall, preclinical studies support the potential of senolytics to enhance efficacy and prolong the antitumor activity of current standard-of-care cancer therapies that promote senescence. However, further work is needed to develop optimal senolytic agents with the appropriate combination of properties for clinical testing, specifically, activity in the context of therapy-induced senescence with acceptable tolerability.

SOHO State of the Art Updates and Next Questions | Updates on Myelofibrosis With Cytopenia

Myelofibrosis (MF) is a rare hematologic malignancy that is characterized by dysregulation of the JAK-STAT pathway resulting in fibrosis of the bone marrow, splenomegaly, and abnormalities in peripheral blood counts including anemia, leukocytosis, and thrombocytopenia. This disease has 2 phenotypic extremes - myeloproliferative and cytopenic. Cytopenic myelofibrosis presents with pronounced cytopenia and a different landscape of genetic mutations which results in worse clinical outcomes and a poor prognosis. Patients with cytopenic MF are at high risk of developing various complications like bleeding, infections, and transfusion dependency. Historically, the only Federal Drug Administration (FDA) approved therapy was ruxolitinib, a JAK1/2 inhibitor, which improved constitutional symptoms and splenomegaly, however, exacerbated anemia and thrombocytopenia.1,2 There were very few options for patients with anemia and thrombocytopenia, and supportive treatments for these problems lack efficacy. Fortunately, there are newer treatment options which may allow for treatment of the symptoms and splenomegaly in the setting of cytopenias and even improve cytopenias. This up-to-date review not only highlights the prevalent options in therapeutic marketplace, but also sheds light on the significant unmet need of addressing anemia and thrombocytopenia in cytopenic MF.

MOMP: A critical event in cell death regulation and anticancer treatment

Mitochondrial outer membrane permeabilization (MOMP) refers to the increase in permeability of the mitochondrial outer membrane, allowing proteins, DNA, and other molecules to pass through the intermembrane space into the cytosol. As a crucial event in the induction of apoptosis, MOMP plays a significant role in regulating various forms of cell death, including apoptosis, ferroptosis, and pyroptosis. Importantly, MOMP is not a binary process of "all-or-nothing." Under sub-lethal stress stimuli, cells may experience a phenomenon referred to as minority MOMP (miMOMP), where only a subset of mitochondria undergo functional impairment, thereby disrupting the normal life cycle of the cell. This can lead to pathological and physiological changes such as tumor formation, cellular senescence, innate immune dysfunction, and chronic inflammation. This review focuses on the diversity of MOMP events to elucidate how varying degrees of MOMP under different stress conditions influence cell fate. Additionally, it summarizes the current research progress on novel antitumor therapeutic strategies targeting MOMP in clinical contexts.

What are the therapeutic options for previously treated myelofibrosis?

INTRODUCTION

The disruption of the JAK/STAT signaling pathway is a defining feature of myelofibrosis (MF). The introduction of JAK inhibitors (JAKi) has transformed the therapeutic approach to MF, becoming essential to treatment and reshaping the management landscape. While JAKi are now the preferred first-line treatment for most patients, various management options are available for those who do not respond to initial therapy.

AREAS COVERED

This review focuses on management options for patients with MF, with particular emphasis on therapeutic strategies following the failure of first-line JAKi. It provides a comprehensive overview of the current treatment landscape, including alternative JAKi and other approaches. The review is based on an extensive literature search using available databases (PubMed, Cochrane …) and relevant web resources (clinicaltrials.gov).

EXPERT OPINION

Ruxolitinib benefits in MF often diminish after 3-4 years, with complications like thrombocytopenia and anemia. Three newer JAKi offer alternatives with similar efficacy and varied side effects. Stem cell transplantation is a curative option for a minority, ideally timed at peak response to JAKi. Research aims to enhance first-line treatments and restore responses in resistant patients. Future therapies may include novel combinations or immunotherapies targeting specific mutations, requiring collaboration between patient, clinical, and pharmaceutical communities.

Pharmacokinetics and Safety of Navitoclax in Hepatic Impairment

BACKGROUND AND OBJECTIVE

Navitoclax, an orally bioavailable B-cell lymphoma-2 (Bcl-2) family protein inhibitor, inhibits antiapoptotic Bcl-2 family proteins (with high affinity to Bcl-XL, Bcl-2, and Bcl-W). Navitoclax in combination with ruxolitinib has been investigated to treat patients with myelofibrosis (MF).

METHODS

Since navitoclax undergoes hepatic metabolism, we evaluated the pharmacokinetics (PK) and safety of single-dose navitoclax 50 mg in a phase 1 study in participants with mild (N = 6), moderate (N = 6), or severe (N = 1) hepatic impairment and matched participants with normal hepatic function (N = 7). All participants in this study were enrolled per Child-Pugh classification, with demographics matched per age, weight, and race.

RESULTS

Navitoclax maximum plasma concentration (Cmax), area under the plasma concentration-time curve for time zero to infinity (AUC0-∞), and terminal elimination half-life (t1/2) in participants with mild or moderate hepatic impairment were comparable to participants with normal hepatic function. The change in Cmax and AUC0-∞ values in participants with mild and moderate hepatic impairment were within 25% of normal hepatic function. Overall, 2/20 (10%) participants receiving a 50 mg single dose reported grade 1 treatment-emergent adverse events of nausea (N = 1) and diarrhea (N = 1).

CONCLUSIONS

In summary, no new safety issues were identified. On the basis of the pharmacokinetic results, no dose adjustment is required for patients with MF with mild or moderate hepatic impairment.

Real World Management of Cytopenias and Infections in Patients With Myelofibrosis Treated With Ruxolitinib

Introduction

Ruxolitinib was the first JAK2 inhibitor approved for the treatment of primary and secondary myelofibrosis. It is currently used worldwide as first-line therapy for advanced disease (intermediate-2 and high-risk) and is effective in polycythaemia vera (PV) and essential thrombocythaemia (ET), but not funded for this indication in many countries. Ruxolitinib has proven benefits with respect to symptom control, reduction in spleen size and prolongation of survival; however, it rarely induces a substantial reduction in allele burden and never provides a cure. Moreover, there are frequently encountered adverse effects and dosing issues that require careful management to optimise its therapeutic benefit.

Methods and Results

In this case-based review, we use seven informative common clinical scenarios to discuss appropriate investigation and management of cytopenias and infection issues.

Conclusions

We make recommendations based on 15 years of experience in using ruxolitinib and other JAK inhibitors for the treatment of myelofibrosis. We discuss when allogeneic haematopoietic stem cell transplantation (AHSCT) should be considered and some of the currently available alternative JAK inhibitors and trial options when AHSCT is not an option.

Construction and validation of a reliable disulfidptosis-related lncRNAs signature of the subtype, prognostic, and immune landscape in bladder cancer

BACKGROUND

Bladder cancer (BLCA) is one of the most frequently-diagnosed tumors globally. Disulfidptosis represents a critical framework for cell death mechanism in cancer therapy. Our study constructed a predictive model utilizing disulfidptosis-related lncRNAs (DRLs) to provide value in evaluating diagnosis, drug sensibility, and prognosis of BLCA patients.

METHODS

The study data of BLCA patients retrieved from TCGA-BLCA database. Cox and LASSO regression analysis were used to identify DRLs. Kaplan-Meier survival analysis, ROC curve, and nomograms were constructed to assess and forecast survival events. GSEA were performed to illustrate relevant enrichments results. Tumor mutation burden (TMB), immune status, and drug sensitivity were assessed. Muscle invasive bladder cancer (MIBC) tumor and tumor-adjacent normal tissues samples were collected in our department to validate the DRLs expression levels by RT-PCR.

RESULTS

Overall, nine DRLs (AL590428.1, LSAMP-AS1, LINC01184, LINC-PINT, AC023825.2, AC010331.1, AC009716.1, AC104785.1, AC008764.6) were identified. These DRLs were used to calculate risk scores and create a prognostic model. ROC revealed higher diagnostic efficiency of the model than other clinical characteristics. Nomogram was constructed using the risk scores, age, and tumor stage, which showed excellent predictive power and was verified by calibration graph. BLCA patients were further classified into high-risk group and low-risk group using median risk score as the cut-off value. The high-risk group showed lesser TMB levels and developed worse prognosis. GSEA of the high-risk group identified pathways associated with BLCA progression such as WNT signaling pathway. Immune cells including CD4+ and CD8+ T cells, and immune-related function like T cell co-stimulation also showed remarkable differences between two risk groups. Furthermore, IC50 values of twelve drugs such as Sorafenib, Nilotinib, and Navitoclax were significantly higher in the high-risk group. RT-PCR results revealed that 9 DRLs expression levels were statistically significant between tumor tissues samples and tumor-adjacent normal tissues samples. The expression trends of these DRLs in clinical tissues samples were the same as the findings in TCGA dataset.

CONCLUSION

Based on this study, it would be advisable to identify the key DRLs with potential prognostic value in BLCA to enhance the evaluation of clinical outcomes in this context.

High-content screening identifies ganoderic acid A as a senotherapeutic to prevent cellular senescence and extend healthspan in preclinical models

Accumulated senescent cells during the aging process are a key driver of functional decline and age-related disorders. Here, we identify ganoderic acid A (GAA) as a potent anti-senescent compound with low toxicity and favorable drug properties through high-content screening. GAA, a major natural component of Ganoderma lucidum, possesses broad-spectrum geroprotective activity across various species. In C. elegans, GAA treatment extends lifespan and healthspan as effectively as rapamycin. Administration of GAA also mitigates the accumulation of senescent cells and physiological decline in multiple organs of irradiation-stimulated premature aging mice, natural aged mice, and western diet-induced obese mice. Notably, GAA displays a capability to enhance physical function and adapts to conditional changes in metabolic demand as mice aged. Mechanistically, GAA directly binds to TCOF1 to maintain ribosome homeostasis and thereby alleviate cellular senescence. These findings suggest a feasible senotherapeutic strategy for protecting against cellular senescence and age-related pathologies.

The BCL2 family: from apoptosis mechanisms to new advances in targeted therapy

The B cell lymphoma 2 (BCL2) protein family critically controls apoptosis by regulating the release of cytochrome c from mitochondria. In this cutting-edge review, we summarize the basic biology regulating the BCL2 family including canonical and non-canonical functions, and highlight milestones from basic research to clinical applications in cancer and other pathophysiological conditions. We review laboratory and clinical development of BH3-mimetics as well as more recent approaches including proteolysis targeting chimeras (PROTACs), antibody-drug conjugates (ADCs) and tools targeting the BH4 domain of BCL2. The first BCL2-selective BH3-mimetic, venetoclax, showed remarkable efficacy with manageable toxicities and has transformed the treatment of several hematologic malignancies. Following its success, several chemically similar BCL2 inhibitors such as sonrotoclax and lisaftoclax are currently under clinical evaluation, alone and in combination. Genetic analysis highlights the importance of BCL-XL and MCL1 across different cancer types and the possible utility of BH3-mimetics targeting these proteins. However, the development of BH3-mimetics targeting BCL-XL or MCL1 has been more challenging, with on-target toxicities including thrombocytopenia for BCL-XL and cardiac toxicities for MCL1 inhibitors precluding clinical development. Tumor-specific BCL-XL or MCL1 inhibition may be achieved by novel targeting approaches using PROTACs or selective drug delivery strategies and would be transformational in many subtypes of malignancy. Taken together, we envision that the targeting of BCL2 proteins, while already a success story of translational research, may in the foreseeable future have broader clinical applicability and improve the treatment of multiple diseases.

Targeting glycolysis in esophageal squamous cell carcinoma: single-cell and multi-omics insights for risk stratification and personalized therapy

Background

Esophageal squamous cell carcinoma (ESCC) is closely linked to aberrant glycolytic metabolism, a hallmark of cancer progression, immune evasion, and therapy resistance. This study employs single-cell transcriptomics and multi-omics approaches to unravel glycolysis-mediated mechanisms in ESCC, with a focus on risk stratification and therapeutic opportunities.

Methods

Data from TCGA and GEO databases were integrated with single-cell RNA sequencing, bulk RNA sequencing, as well as clinical datasets to investigate glycolysis-associated cell subtypes and their clinical implications in ESCC. Analytical approaches encompassed cell subtype annotation, cell-cell communication network analysis, and gene regulatory network modeling. A glycolysis-related risk score model was built via non-negative matrix factorization (NMF) and Cox regression, and then experimentally verified through Western blotting. Drug sensitivity analyses were carried out to explore potential therapeutic strategies.

Results

Single-cell analysis identified epithelial cells as the dominant glycolysis-active subtype, and tumor tissues showed significantly higher glycolytic activity than adjacent normal tissues. Among malignant epithelial subpopulations, IGFBP3+Epi (IGFBP3-expressing epithelial cells) and LHX9+Epi (LHX9-expressing epithelial cells) had elevated glycolysis levels, which correlated with poor prognosis, immune suppression, and changes in the tumor microenvironment. The seven-gene glycolysis-based risk score model divided patients into high- and low-risk groups, demonstrating strong prognostic performance. Drug sensitivity analysis showed high-risk patients were more responsive to Navitoclax as well as Rapamycin, but low-risk ones were more sensitive to Afatinib and Erlotinib, highlighting the model's usefulness in guiding personalized treatment.

Conclusion

This research emphasizes the crucial role of glycolysis in ESCC progression a well as immune modulation, offering a novel glycolysis-related risk score model with significant prognostic and therapeutic implications. These findings provide a basis for risk-based stratification and tailored therapeutic strategies, advancing precision medicine in ESCC.

Model-Assisted Spleen Contouring for Assessing Splenomegaly in Myelofibrosis: A Fast and Reproducible Approach to Evaluate Progression and Treatment Response

Background/Objectives: Accurate and reproducible spleen volume measurements are essential for assessing treatment response and disease progression in myelofibrosis. This study evaluates techniques for measuring spleen volume on abdominal MRI. Methods: In 20 patients with bone marrow biopsy-proven myelofibrosis, 5 observers independently measured spleen volume on 3 abdominal MRI pulse sequences, 3D-spoiled gradient echo T1, axial single-shot fast spin echo (SSFSE) T2, and coronal SSFSE T2, using ellipsoidal approximation, manual contouring, and 3D nnU-Net model-assisted contouring comparing coefficients of variation. Changes in spleen volume were compared to all information to assess which measurement technique tracked disease progression with the greatest accuracy. Results: The coefficient of variation in spleen volume measurements averaging over 3 sequences was significantly lower for model-assisted contouring, 1.6% and manual contouring, 3.5%, compared to ellipsoidal estimation from 3 dimensions measured on axial and coronal T2 images, 15, p < 0.001. In 4 subjects with divergent treatment response predictions, model-assisted contouring was consistent with all information while ellipsoidal estimation was not. Manual contouring tracked similarly to model-assisted contouring but required more operator time. Conclusions: Model-assisted segmentations provide efficient and more reproducible spleen volume measurements compared to estimates of spleen volume from ellipsoidal approximations and improve objective determinations of clinical trial enrollment eligibility based upon spleen volume as well as assessments of treatment response.

Impact of Recent Translational and Therapeutic Developments on Clinical Course of BCR::ABL1-Positive and -Negative Myeloproliferative Neoplasms

Despite the study of BCR::ABL1-positive and -negative myeloproliferative neoplasms (MPNs) providing seminal insights into cancer biology, tumor evolution and precision oncology over the past half century, significant challenges remain. MPNs are clonal hematopoietic stem cell-derived neoplasms with heterogenous clinical phenotypes and a clonal architecture which impacts the often-complex underlying genetics and microenvironment. The major driving molecular abnormalities have been well characterized, but debate on their role as disease-initiating molecular lesions continues. The introduction of the ABL1 tyrosine kinase inhibitors have been extremely successful in the treatment of chronic myeloid leukemia with most patients having a near-normal life expectancy. Similar success has, however, not been achieved for BCR::ABL1-negative MPNs in terms of disease course modification and most patients remain incurable. In both disease categories, genomic instability seems to increase the risk of disease progression to accelerated/blast phase, which is resistant/refractory to conventional treatment and associated with a poor prognosis. To address some of these issues, the late John Goldman and Tariq Mughal founded a scientific and clinical platform in 2006, the Post-American Society of Hematology (ASH) MPN workshop, to appraise novel cancer biology, candidate therapeutic targets, treatments and other clinical challenges and pay tribute to all the many scientists and clinicians around the world instrumental to the progress made and continuing advances being made. This paper summarizes some of the recent data discussed at the 18th edition of the workshop and includes reference to some data presented or published after the workshop, including the 26th John Goldman CML conference.

A Comprehensive Insight into Apoptosis: Molecular Mechanisms, Signaling Pathways, and Modulating Therapeutics

Apoptosis, or programmed cell death, is a fundamental biological process essential for maintaining tissue homeostasis. Dysregulation of apoptosis is implicated in a variety of diseases, including cancer, neurodegenerative disorders, and autoimmune conditions. This review provides an in-depth insight into the molecular mechanisms and signaling pathways that regulate apoptosis, highlighting both intrinsic and extrinsic pathways. Additionally, the review explains the tumor microenvironment's influence on apoptosis and its implications for cancer therapy resistance. Understanding the complex interplay between apoptotic signaling and cellular responses is crucial for developing targeted therapies that can effectively manage diseases associated with apoptosis dysregulation. The effects of conventional therapeutics and alternative substances with natural sources such as herbal compounds, alongside vitamins, minerals, and trace elements on cellular homeostasis and disease pathogenesis have been thoroughly investigated. Moreover, recent advances in therapeutic strategies aimed at modulating apoptosis are discussed, with a focus on novel interventions such as nutrition bio shield dietary supplement. These emerging approaches offer potential benefits beyond conventional treatments by selectively targeting apoptotic pathways to inhibit cancer progression and metastasis. By integrating insights from recent studies, this review aims to enhance our understanding of apoptosis and guide future research in developing innovative therapeutic approaches.

Advances in Stem Cell Transplantation for Myelofibrosis

PURPOSE OF REVIEW

Allogeneic hematopoietic cell transplantation is the only potentially curative treatment for myelofibrosis. This review discusses issues not well-covered by existing guidelines: timing of transplant, pre-transplant spleen management and alternative donors; providing our approach to these situations.

RECENT FINDINGS

Research continues to allow better identification, by better risk stratification and advances in understanding likelihood of durable JAKi response, which patients are likely to derive benefit from upfront transplant versus those for whom delayed transplant may be more appropriate. Several options of JAKi therapy provide a non-surgical option for pre-HCT splenomegaly management, allowing some patients to avoid risks associated with splenectomy. Recent years have also seen a sharp spike in haploidentical donor transplants, along with narrowing of the gap in outcomes between donor types. Continuous enrollment in prospective studies or well-designed registries is required to generate the high-quality data needed to develop better decision tools for these scenarios.

Janus kinase inhibitor monotherapy and combination therapies for myelofibrosis: what's the current standard of care?

INTRODUCTION

JAK inhibitors (JAKi) have changed the treatment paradigm of myelofibrosis (MF). Currently, 4 JAKis are approved in the US as monotherapy (mono) to treat patients with MF. JAKis are also being studied in combination (combo) with novel agents. Herein, we review some of the key studies that evaluated JAKi as mono and combo in MF.

AREAS COVERED

We performed a Pubmed search for 'JAK inhibitors' and 'myelofibrosis' from 1/2010 to 12/2023. For mono, we included only the unique phase II/III studies of the approved JAKi. Selective studies that evaluated JAKi in combo with the novel agents were also included.

EXPERT OPINION

JAKis aim to provide clinical benefit to patients via spleen size reduction and MPN symptom improvement. In order to potentially increase clinical benefit for patients with MF, several novel agents are being partnered with ruxolitinib (RUX) with the ongoing hypothesis to augment greater measures of MF disease modification. The novel agents are either 'added-on' to RUX or as a combo in JAKi naïve patients. Also, the mutant-targeting era of therapies is now beginning with novel CALR-mutated, novel JAK2 V617F mutation-specific and type II JAK2i in the initial stages of drug development, representing a new approach to treatment.

Identifying disease-modifying potential in myelofibrosis clinical trials

ABSTRACT

The ultimate goal of bringing most new drugs to the clinic in hematologic malignancy is to improve overall survival. However, the use of surrogate end points for overall survival is increasingly considered standard practice, because a well validated surrogate end point can accelerate the outcome assessment and facilitate better clinical trial design. Established examples include monitoring minimal residual disease in chronic myeloid leukemia and acute leukemia, and metabolic response assessment in lymphoma. However, what happens when a clinical trial end point that is not a good surrogate for disease-modifying potential becomes ingrained as an expected outcome, and new agents are expected or required to meet this end point to demonstrate "efficacy"? Janus kinase (JAK) inhibitors for myelofibrosis (MF) have a specific impact on reducing symptom burden and splenomegaly but limited impact on the natural history of the disease. Since the introduction of ruxolitinib more than a decade ago there has been modest incremental success in clinical trials for MF but no major leap forward to alter the natural history of the disease. We argue that the clinical development of novel agents for MF will be accelerated by moving away from using end points that are specifically tailored to measure the beneficial effects of JAK inhibitors. We propose that specific measures of relevant disease burden, such as reduction in mutation burden as determined by molecular end points, should replace established end points. Careful reanalysis of existing data and trials in progress is needed to identify the most useful surrogate end points for future MF trials and better serve patient interest.

Relapse and resistance in acute myeloid leukemia post venetoclax: improving second lines therapy and combinations

INTRODUCTION

The combined use of the BCL-2 inhibitor venetoclax with azacitidine now is the standard of care for patients with acute myeloid leukemia (AML) unfit for intensive chemotherapy with outcomes exceeding those achieved with hypomethylating agents alone. Venetoclax in combination with intensive chemotherapy is also increasingly used both as frontline as well as salvage therapy. However, resistance to and relapse after venetoclax-based therapies are of major concern and outcomes after treatment failure remain poor.

AREAS COVERED

A comprehensive search was performed using PubMed database (up to April 2024). Studies evaluating venetoclax-based combination treatments in AML and studies assessing markers of response and resistance to venetoclax were investigated. We summarize the status of venetoclax-based therapies in the frontline and relapsed/refractory setting with focus on the main mechanisms of resistance to BCL-2 inhibition. Further, strategies to overcome resistance including combinatorial regimens of hypomethylating agent (HMA) + venetoclax + inhibitors targeting actionable mutations like IDH1/2 or FLT3-ITD and the introduction of novel agents like menin-inhibitors are addressed.

EXPERT OPINION

Although venetoclax is reshaping the treatment of unfit and fit AML patients, prognosis of patients after HMA/VEN failure remains dismal, and strategies to abrogate primary and secondary resistance are an unmet clinical need.

Peptide-Amphiphilic Nanoassemblies as a Responsive Senolytic Navigator for Targeted Removal of Senescent Cardiomyocytes to Ameliorate Heart Failure

Heart failure (HF) represents the terminal stage of numerous cardiovascular disorders and lacks effective therapeutic strategies. The accumulation of senescent cardiomyocytes is a cardinal characteristic of HF, contributing to myocardial dysfunction and deteriorating the myocardial microenvironment through the development of senescence-associated secretory phenotypes (SASPs), ultimately culminating in pathological remodeling. Senolytics, a promising therapeutic strategy that selectively induces apoptosis in senescent cells, faces challenges due to nonspecific effects, raising concerns for clinical implementation. In this study, we developed peptide-amphiphilic nanoassemblies as responsive drug navigators for targeted delivery. The modular nanoassemblies comprise a hydrophilic domain containing a CD9-binding peptide, a hydrophobic domain incorporating a reactive oxygen species (ROS)-responsive motif, and an alkyl tail for encapsulation of the senolytic ABT263. The CD9-targeted and ROS-responsive nanoassemblies (AP@ABT263) specifically recognized senescent cardiomyocytes and modulated the release of ABT263 in the presence of elevated intracellular ROS levels. AP@ABT263 treatment significantly enhanced the targeted delivery of ABT263 to senescent cells in both in vitro and in vivo while showing minimal toxicity to normal cardiomyocytes and other tissues. Our findings provide compelling evidence that AP@ABT263 efficiently eradicated senescent cardiomyocytes, enhanced cardiac function, and attenuated the deleterious effects of SASP, thereby preventing adverse cardiac remodeling. In summary, AP@ABT263 represents a highly promising approach for responsive and controlled drug release in senescent cardiomyocytes, providing valuable insights into the development of intelligent pharmaceutical interventions for the management of HF.

Emerging drug profile: JAK inhibitors

Dysregulated JAK/STAT hyperactivity is essential to the pathogenesis of myelofibrosis, and JAK inhibitors are the first-line treatment option for many patients. There are four FDA-approved JAK inhibitors for patients with myelofibrosis. Single-agent JAK inhibition can improve splenomegaly, symptom burden, cytopenias, and possibly survival in patients with myelofibrosis. Despite their efficacy, JAK inhibitors produce variable or short-lived responses, in part due to the large network of cooperating signaling pathways and downstream targets of JAK/STAT, which mediates upfront or acquired resistance to JAK inhibitors. Synergistic inhibition of JAK/STAT accessory pathways can increase the rates and duration of response for patients with myelofibrosis. Two recently reported, placebo-controlled phase III trials of novel agents added to JAK inhibition met their primary endpoint, and additional late-stage studies are ongoing. This paper will review role of dysregulated JAK/STAT signaling, biological plausible additional therapeutic targets and the recent advancements in combination strategies with JAK inhibitors for myelofibrosis.

Cellular senescence in metastatic prostate cancer: A therapeutic opportunity or challenge (Review)

The treatment of patients with metastatic prostate cancer (PCa) is considered to be a long‑standing challenge. Conventional treatments for metastatic PCa, such as radical prostatectomy, radiotherapy and androgen receptor‑targeted therapy, induce senescence of PCa cells to a certain extent. While senescent cells can impede tumor growth through the restriction of cell proliferation and increasing immune clearance, the senescent microenvironment may concurrently stimulate the secretion of a senescence‑associated secretory phenotype and diminish immune cell function, which promotes PCa recurrence and metastasis. Resistance to established therapies is the primary obstacle in treating metastatic PCa as it can lead to progression towards an incurable state of disease. Therefore, understanding the molecular mechanisms that underly the progression of PCa is crucial for the development of novel therapeutic approaches. The present study reviews the phenomenon of treatment‑induced senescence in PCa, the dual role of senescence in PCa treatments and the mechanisms through which senescence promotes PCa metastasis. Furthermore, the present review discusses potential therapeutic strategies to target the aforementioned processes with the aim of providing insights into the evolving therapeutic landscape for the treatment of metastatic PCa.

Liver and spleen shear-wave elastography in the diagnosis and severity staging of myeloproliferative diseases and myelofibrosis

AIMS

Spleen and liver stiffness, investigated by VCTE (Vibration-Controlled Transient Elastography), have been associated with marrow fibrosis in patients with myeloproliferative neoplasms (MPNs). Tissue stiffness can be assessed by shear wave point (pSWE) and bidimensional elastography (2DSWE). Spleen stiffness (SS) values were higher in Myelofibrosis (MF) and Polycythemia Vera (PV) compared to Essential Thrombocythemia (ET). We aimed to identify SWE differences between MPN patients and healthy volunteers; to evaluate specific SWE features in patients with MF, PV and ET; to establish a correlation with bone marrow fibrosis in patients with myeloproliferative disease.

METHODS

Patients with myeloproliferative disease and healthy volunteers performed evaluation of spleen and liver stiffness (LS) by pSWE and 2DSWE.

RESULTS

A total of 218 subjects were included: 143 with myeloproliferative disease (64 MF, 29.4%, 33 PV, 15.1% and 46 ET, 21.1%), and 75 (34.4%) healthy volunteers. Compared to volunteers, MF patients had greater spleen (pSWE 40.9 vs. 26.3 kPa, p < 0.001; 2DSWE 34.9 vs. 20.1 kPa, p < 0.001), and liver stiffness (pSWE 7.72 vs. 5.52 kPa, p < 0.001; 2DSWE 6.96 vs. 5.01 kPa, p < 0.001). In low (0-1) (n = 81, 60.4%) versus high-grade bone marrow fibrosis (2-3) (n = 42, 39.6%), is evident a higher median stiffness in patients with higher grades of fibrosis both for liver (pSWE 5.2 vs. 6.65 kPa; 2DSWE 5.1 vs. 6.05 kPa) and spleen (pSWE 27.2 vs. 37.9 kPa, 2DSWE 21.7 vs 30.75 kPa-p < 0.001 in both).

CONCLUSION

SWE evaluation distinguishes MF patients from HV and ET/PV and may help in MPN diagnosis. LS and SS values are associated with bone marrow fibrosis grade.

Navitoclax safety, tolerability, and effect on biomarkers of senescence and neurodegeneration in aged nonhuman primates

Alzheimer's disease (AD) is the most common global dementia and is universally fatal. Most late-stage AD disease-modifying therapies are intravenous and target amyloid beta (Aβ), with only modest effects on disease progression: there remains a high unmet need for convenient, safe, and effective therapeutics. Senescent cells (SC) and the senescence-associated secretory phenotype (SASP) drive AD pathology and increase with AD severity. Preclinical senolytic studies have shown improvements in neuroinflammation, tau, Aβ, and CNS damage; most were conducted in transgenic rodent models with uncertain human translational relevance. In this study, aged cynomolgus monkeys had significant elevation of biomarkers of senescence, SASP, and neurological damage. Intermittent treatment with the senolytic navitoclax induced modest reversible thrombocytopenia; no serious drug-related toxicity was noted. Navitoclax reduced several senescence and SASP biomarkers, with CSF concentrations sufficient for senolysis. Finally, navitoclax reduced TSPO-PET frontal cortex binding and showed trends of improvement in CSF biomarkers of neuroinflammation, neuronal damage, and synaptic dysfunction. Overall, navitoclax administration was safe and well tolerated in aged monkeys, inducing trends of biomarker changes relevant to human neurodegenerative disease.

Donor types and outcomes of transplantation in myelofibrosis: a CIBMTR study

ABSTRACT

We evaluate the impact of donor types on outcomes of hematopoietic cell transplantation (HCT) in myelofibrosis, using the Center for International Blood and Marrow Transplant Research registry data for HCTs done between 2013 and 2019. In all 1597 patients, the use of haploidentical donors increased from 3% in 2013 to 19% in 2019. In study-eligible 1032 patients who received peripheral blood grafts for chronic-phase myelofibrosis, 38% of recipients of haploidentical HCT were non-White/Caucasian. Matched sibling donor (MSD)-HCTs were associated with superior overall survival (OS) in the first 3 months (haploidentical hazard ratio [HR], 5.80 [95% confidence interval (CI), 2.52-13.35]; matched unrelated (MUD) HR, 4.50 [95% CI, 2.24-9.03]; mismatched unrelated HR, 5.13 [95% CI, 1.44-18.31]; P < .001). This difference in OS aligns with lower graft failure with MSD (haploidentical HR, 6.11 [95% CI, 2.98-12.54]; matched unrelated HR, 2.33 [95% CI, 1.20-4.51]; mismatched unrelated HR, 1.82 [95% CI, 0.58-5.72]). There was no significant difference in OS among haploidentical, MUD, and mismatched unrelated donor HCTs in the first 3 months. Donor type was not associated with differences in OS beyond 3 months after HCT, relapse, disease-free survival, or OS among patients who underwent HCT within 24 months of diagnosis. Patients who experienced graft failure had more advanced disease and commonly used nonmyeloablative conditioning. Although MSD-HCTs were superior, there is no significant difference in HCT outcomes from haploidentical and MUDs. These results establish haploidentical HCT with posttransplantation cyclophosphamide as a viable option in myelofibrosis, especially for ethnic minorities underrepresented in the donor registries.

LILRB2 inhibition enhances radiation sensitivity in non-small cell lung cancer by attenuating radiation-induced senescence

Radiotherapy (RT) in non-small cell lung cancer (NSCLC) triggers cellular senescence, complicating tumor microenvironments and affecting treatment outcomes. This study examines the role of lymphocyte immunoglobulin-like receptor B2 (LILRB2) in modulating RT-induced senescence and radiosensitivity in NSCLC. Through methodologies including irradiation, lentivirus transfection, and various molecular assays, we assessed LILRB2's expression and its impact on cellular senescence levels and tumor cell behaviors. Our findings reveal that RT upregulates LILRB2, facilitating senescence and a senescence-associated secretory phenotype (SASP), which in turn enhances tumor proliferation and resistance to radiation. Importantly, LILRB2 silencing attenuates these effects by inhibiting the JAK2/STAT3 pathway, significantly increasing radiosensitivity in NSCLC models. Clinical data correlate high LILRB2 expression with reduced RT response and poorer prognosis, suggesting LILRB2's pivotal role in RT-induced senescence and its potential as a therapeutic target to improve NSCLC radiosensitivity.

Myeloproliferative neoplasms in the adolescent and young adult population: A comprehensive review of the literature

Myeloproliferative neoplasms (MPN) are characterized by a clonal proliferation of myeloid lineage cells within the bone marrow. The classical BCR-ABL negative MPNs are comprised of polycythaemia vera, essential thrombocythaemia and primary myelofibrosis. Historically, the majority of MPNs are diagnosed in adults older than 60 years of age; however, in recent years, there has been recognition of MPNs in the adolescent and young adult (AYA) population. AYAs with MPN, typically defined as between the ages of 15 and 39 years old, may comprise up to 20% of patients diagnosed with MPN. They demonstrate unique patterns of driver mutations and thrombotic events and remain at risk for progression to more aggressive disease states. Given the likely long length of time they will live with their disease, there is a significant unmet need in identifying well-tolerated and effective treatment options for these patients, particularly with the advent of disease modification. In this review, we provide a comprehensive overview of the clinical features, disease course and management of AYA patients with MPN and, in doing so, highlight key characteristics that distinguish them from their older counterparts.

Myelofibrosis: Current unmet needs, emerging treatments, and future perspectives

The current standard-of-care for treatment of myelofibrosis (MF) comprises inhibitors of the Janus kinase (JAK)/signal transducers and activators (STAT) pathway; however, despite their ability to alleviate symptoms, they do not appear to modify underlying disease and have not demonstrated substantial survival benefit. Allogeneic-hematopoietic stem cell transplantation remains the only curative option for patients with MF but is limited to a subset of high-risk and fit patients. Early disease modification could positively affect disease trajectory for lower risk patients with MF as well as those with conditions that can precede MF, such as polycythemia vera and essential thrombocythemia. Here, the authors discuss critical unmet needs in the MF treatment paradigm, including: the need for safe, impactful therapies for lower risk patients, thus allowing intervention when success is most likely; better development of first-line therapies (likely highly novel or combination strategies) for intermediate-risk/higher risk patients; and approved drugs to manage cytopenia. Finally, a consensus definition of disease modification is needed that informs trial design, allowing the development of clinical end points that enable understanding of therapies and responses and that facilitate the development of therapies that work according to this definition. Through close collaboration between clinicians, patients, and the pharmaceutical industry, better efforts to define benefit and identify patients most likely to benefit from a particular combination or treatment strategy should enable the development of more effective and safe treatments to extend and improve quality of life for patients with MF.

Venetoclax therapy and emerging resistance mechanisms in acute myeloid leukaemia

Acute myeloid leukaemia (AML) is a highly aggressive and devastating malignancy of the bone marrow and blood. For decades, intensive chemotherapy has been the frontline treatment for AML but has yielded only poor patient outcomes as exemplified by a 5-year survival rate of < 30%, even in younger adults. As knowledge of the molecular underpinnings of AML has advanced, so too has the development new strategies with potential to improve the treatment of AML patients. To date the most promising of these targeted agents is the BH3-mimetic venetoclax which in combination with standard of care therapies, has manageable non-haematological toxicity and exhibits impressive efficacy. However, approximately 30% of AML patients fail to respond to venetoclax-based regimens and almost all treatment responders eventually relapse. Here, we review the emerging mechanisms of intrinsic and acquired venetoclax resistance in AML and highlight recent efforts to identify novel strategies to overcome resistance to venetoclax.

Recent advances in JAK2 inhibition for the treatment of myelofibrosis

INTRODUCTION

Myelofibrosis (MF) is a BCR-ABL-negative myeloproliferative neoplasm characterized by splenomegaly, constitutional symptoms, cytopenias, a potential for leukemic transformation, and increased mortality. Patients who are ineligible for stem cell transplant rely on pharmacologic therapies of noncurative intent, whose cornerstone consists of JAK inhibitors (JAKi). While current JAKi are efficacious in controlling symptoms and splenic volume, none meaningfully reduce clonal burden nor halt disease progression, and patients oftentimes develop JAKi intolerant, relapsed, or refractory MF. As such, there remains an urgent necessity for second-line options and novel therapies with disease-modifying properties.

AREAS COVERED

In this review, we delineate the mechanistic rationale, along with the latest safety and efficacy data, of investigational JAKi-based MF treatment strategies, with a focus on JAKi monotherapies and combinations of novel agents with approved JAKi. Our literature search consisted of extensive review of PubMed and clinicaltrials.gov.

EXPERT OPINION

A myriad of promising MF-directed therapies are in late-phase studies. Following their approval, treatment selection should be tailored to patient-specific treatment goals and disease characteristics, with an emphasis on combination therapies of JAKi with novel agents of differing mechanistic targets that possess anti-clonal properties, in attempt to alter disease course and concurrently limit dose-dependent JAKi toxicities.

SHP2 inhibition displays efficacy as a monotherapy and in combination with JAK2 inhibition in preclinical models of myeloproliferative neoplasms

Myeloproliferative neoplasms (MPNs), including polycythemia vera, essential thrombocytosis, and primary myelofibrosis, are clonal hematopoietic neoplasms driven by mutationally activated signaling by the JAK2 tyrosine kinase. Although JAK2 inhibitors can improve MPN patients' quality of life, they do not induce complete remission as disease-driving cells persistently survive therapy. ERK activation has been highlighted as contributing to JAK2 inhibitor persistent cell survival. As ERK is a component of signaling by activated RAS proteins and by JAK2 activation, we sought to inhibit RAS activation to enhance responses to JAK2 inhibition in preclinical MPN models. We found the SHP2 inhibitor RMC-4550 significantly enhanced growth inhibition of MPN cell lines in combination with the JAK2 inhibitor ruxolitinib, effectively preventing ruxolitinib persistent growth, and the growth and viability of established ruxolitinib persistent cells remained sensitive to SHP2 inhibition. Both SHP2 and JAK2 inhibition diminished cellular RAS-GTP levels, and their concomitant inhibition enhanced ERK inactivation and increased apoptosis. Inhibition of SHP2 inhibited the neoplastic growth of MPN patient hematopoietic progenitor cells and exhibited synergy with ruxolitinib. RMC-4550 antagonized MPN phenotypes and increased survival of an MPN mouse model driven by MPL-W515L. The combination of RMC-4550 and ruxolitinib, which was safe and tolerated in healthy mice, further inhibited disease compared to ruxolitinib monotherapy, including extending survival. Given SHP2 inhibitors are undergoing clinical evaluation in patients with solid tumors, our preclinical findings suggest that SHP2 is a candidate therapeutic target with potential for rapid translation to clinical assessment to improve current targeted therapies for MPN patients.

Evaluation of BH3 mimetics as a combination therapy with irradiation in head and neck squamous cell carcinoma

INTRODUCTION

Head and neck squamous cell carcinoma (HNSCC) is a common cancer with a five-year survival rate around 60%, indicating a need for new treatments. BH3 mimetics are small molecules that inhibit anti-apoptotic Bcl-2 family proteins, resulting in apoptosis induction.

METHODS

We performed a high-throughput screen using a Myogel matrix to identify the synergy between irradiation and the novel BH3 mimetics A-1155463, A-1331852, and navitoclax in 12 HNSCC cell lines, normal (NOF) and cancer-associated fibroblasts (CAF), and dysplastic keratinocytes (ODA). Next, we examined synergy in an apoptosis assay, followed by a clonogenic assay and a Myogel spheroid on selected HNSCC cell lines. Finally, we applied zebrafish larvae xenograft to validate the effects of navitoclax and A-1331852.

RESULTS

All three BH3 mimetics exhibited a strong synergy with irradiation in eight HNSCC cell lines and ODAs, but not in NOFs and CAFs. A-1155463 and A-1331852 induced apoptosis and reduced proliferation, and together with irradiation, significantly increased apoptosis and arrested proliferation. A-1331852 and navitoclax significantly decreased the clonogenicity compared with the control, and combination treatment led to a decreased clonogenicity compared with monotherapy or irradiation. However, unlike navitoclax or A-1155463, only A-1331852 significantly reduced cancer cell invasion. Furthermore, in spheroid and zebrafish, irradiation appeared ineffective and failed to significantly increase the drug effect. In the zebrafish, A-1331852 and navitoclax significantly reduced the tumor area and metastasis.

CONCLUSIONS

Our findings encourage the further preclinical investigation of BH3 mimetics, particularly A-1331852, as a single agent or combined with irradiation as a treatment for HNSCC.

Cellular senescence promotes meibomian gland dysfunction in a chronic graft-versus-host disease mouse model

PURPOSE

Aging is a well-established risk factor for meibomian gland dysfunction (MGD). We previously reported an accelerated cellular senescence phenomenon in the lacrimal glands of a murine model of chronic graft-versus-host disease (cGVHD). Herein, we aimed to elucidate the relationship between cellular senescence and MGD in cGVHD mice, utilizing the senolytic agent ABT-263.

METHODS

A cGVHD mouse model was established through allogeneic bone marrow transplantation (BMT) from B10.D2 to BALB/c mice. Subsequently, cGVHD mice were treated with either ABT-263 or vehicle. The eyelids of recipients were analyzed at 4-week intervals post-BMT in both groups.

RESULTS

Meibomian gland (MG) area was significantly smaller in cGVHD mice than in syngeneic control mice. ABT-263-treated mice retained a significantly larger MG area than their vehicle-treated counterparts. Pathological and immunohistochemical examinations revealed significant reductions in eyelid tissue inflammation and pathological fibrosis in the ABT-263 group compared to that in the vehicle-treated group. Additionally, expression of DNA damage markers, senescent cell markers, and senescence-associated secretory phenotype (SASP) factors was elevated in the eyelids of cGVHD mice compared with that in syngeneic mice. The expression of these cellular senescence-associated molecules was considerably suppressed in ABT-263-treated eyelids compared to that in vehicle-treated ones.

CONCLUSIONS

Cellular senescence, along with expression of SASP factors, exhibited increased activity in the eyelids, particularly in the MGs of cGVHD mice. ABT-263 mitigated the severity of MGD. These findings highlight the potential of targeting cellular senescence as an effective approach for MGD treatment in cGVHD.

Advances in pharmacotherapy for myelofibrosis: what is the current state of play?

INTRODUCTION

The introduction of the first JAK inhibitor (JAKi) ruxolitinib 10 years ago represented a pivotal advancement in myelofibrosis (MF) treatment, mostly in terms of spleen and symptoms response. Nowadays three more JAKi, fedratinib, pacritinib, and momelotinib, are available for both ruxolitinib-resistant and naïve patients. Moreover, many drugs are currently being investigated, both alone and in combination with JAKi.

AREAS COVERED

In this review we discuss the long-term data of ruxolitinib and more recent evidence coming from clinical trials of fedratinib, pacritinib, and momelotinib, used as first- or second-line MF therapy. More, focus is set on data from non-JAKi drugs, such as the quite extensively studied BET-inhibitors (pelabresib) and BCL-inhibitors (navitoclax), novel target therapies, and drugs aimed to improve anemia, still representing a major determinant of reduced survival in MF.

EXPERT OPINION

It's now evident that JAKi monotherapy, though clinically effective, is rarely able to change MF natural history; novel drugs are promising but long-term data are inevitably lacking. We feel that soon MF treatment will require clinicians to select the most appropriate JAKi inhibitor, based on patient characteristics, associating either front-line or in case of early suboptimal response, non-JAKi drugs with the aim to pursue disease modification.

Phase 2 study of add-on parsaclisib for patients with myelofibrosis and suboptimal response to ruxolitinib: final results

ABSTRACT

Ruxolitinib reduces spleen volume, improves symptoms, and increases survival in patients with intermediate- or high-risk myelofibrosis. However, suboptimal response may occur, potentially because of signaling via the phosphoinositide 3-kinase (PI3K)/protein kinase B pathway. This phase 2 study evaluated dosing, efficacy, and safety of add-on PI3Kδ inhibitor parsaclisib for patients with primary or secondary myelofibrosis with suboptimal response to ruxolitinib. Eligible patients remained on a stable ruxolitinib dose and received add-on parsaclisib 10 or 20 mg, once daily for 8 weeks, and once weekly thereafter (daily-to-weekly dosing; n = 32); or parsaclisib 5 or 20 mg, once daily for 8 weeks, then 5 mg once daily thereafter (all-daily dosing; n = 42). Proportion of patients achieving a ≥10% decrease in spleen volume at 12 weeks was 28% for daily-to-weekly dosing and 59.5% for all-daily dosing. Proportions of patients achieving ≥50% decrease at week 12 in Myelofibrosis Symptom Assessment Form and Myeloproliferative Neoplasms Symptom Assessment Form symptom scores were 14% and 18% for daily-to-weekly dosing, and 28% and 32% for all-daily dosing, respectively. Most common nonhematologic treatment-emergent adverse events were nausea (23%), diarrhea (22%), abdominal pain and fatigue (each 19%), and cough and dyspnea (each 18%). New-onset grade 3 and 4 thrombocytopenia were observed in 19% of patients, each dosed daily-to-weekly, and in 26% and 7% of patients dosed all-daily, respectively, managed with dose interruptions. Hemoglobin levels remained steady. The addition of parsaclisib to stable-dose ruxolitinib can reduce splenomegaly and improve symptoms, with manageable toxicity in patients with myelofibrosis with suboptimal response to ruxolitinib. This trial was registered at www.clinicaltrials.gov as #NCT02718300.

Small-molecule agents for cancer immunotherapy

Cancer immunotherapy, exemplified by the remarkable clinical benefits of the immune checkpoint blockade and chimeric antigen receptor T-cell therapy, is revolutionizing cancer therapy. They induce long-term tumor regression and overall survival benefit in many types of cancer. With the advances in our knowledge about the tumor immune microenvironment, remarkable progress has been made in the development of small-molecule drugs for immunotherapy. Small molecules targeting PRR-associated pathways, immune checkpoints, oncogenic signaling, metabolic pathways, cytokine/chemokine signaling, and immune-related kinases have been extensively investigated. Monotherapy of small-molecule immunotherapeutic drugs and their combinations with other antitumor modalities are under active clinical investigations to overcome immune tolerance and circumvent immune checkpoint inhibitor resistance. Here, we review the latest development of small-molecule agents for cancer immunotherapy by targeting defined pathways and highlighting their progress in recent clinical investigations.

Recruitment of BAG2 to DNAJ-PKAc scaffolds promotes cell survival and resistance to drug-induced apoptosis in fibrolamellar carcinoma

The DNAJ-PKAc fusion kinase is a defining feature of fibrolamellar carcinoma (FLC). FLC tumors are notoriously resistant to standard chemotherapies, with aberrant kinase activity assumed to be a contributing factor. By combining proximity proteomics, biochemical analyses, and live-cell photoactivation microscopy, we demonstrate that DNAJ-PKAc is not constrained by A-kinase anchoring proteins. Consequently, the fusion kinase phosphorylates a unique array of substrates, including proteins involved in translation and the anti-apoptotic factor Bcl-2-associated athanogene 2 (BAG2), a co-chaperone recruited to the fusion kinase through association with Hsp70. Tissue samples from patients with FLC exhibit increased levels of BAG2 in primary and metastatic tumors. Furthermore, drug studies implicate the DNAJ-PKAc/Hsp70/BAG2 axis in potentiating chemotherapeutic resistance. We find that the Bcl-2 inhibitor navitoclax enhances sensitivity to etoposide-induced apoptosis in cells expressing DNAJ-PKAc. Thus, our work indicates BAG2 as a marker for advanced FLC and a chemotherapeutic resistance factor in DNAJ-PKAc signaling scaffolds.

Changes in bone marrow fibrosis during momelotinib or ruxolitinib therapy do not correlate with efficacy outcomes in patients with myelofibrosis

Bone marrow fibrosis (BMF) is a pathological feature of myelofibrosis, with higher grades associated with poor prognosis. Limited data exist on the association between outcomes and BMF changes. We present BMF data from Janus kinase (JAK) inhibitor-naive patients from SIMPLIFY-1 (NCT01969838), a double-blind, randomized, phase 3 study of momelotinib vs ruxolitinib. Baseline and week 24 bone marrow biopsies were graded from 0 to 3 as per World Health Organization criteria. Other assessments included Total Symptom Score, spleen volume, transfusion independence status, and hemoglobin levels. Paired samples were available from 144 and 160 patients randomized to momelotinib and ruxolitinib. With momelotinib and ruxolitinib, transfusion independence was achieved by 87% and 44% of patients with BMF improvement of ≥1 grade and 76% and 56% of those with stable/worsening BMF; there was no association between BMF changes and transfusion independence for either arm (momelotinib, p = .350; ruxolitinib, p = .096). Regardless of BMF changes, hemoglobin levels also generally increased on momelotinib but decreased on ruxolitinib. In addition, no associations between BMF changes and spleen (momelotinib, p = .126; ruxolitinib, p = .407)/symptom (momelotinib, p = .617; ruxolitinib, p = .833) outcomes were noted, and no improvement in overall survival was observed with ≥1-grade BMF improvement (momelotinib, p = .395; ruxolitinib, p = .407). These data suggest that the anemia benefit of momelotinib is not linked to BMF changes, and question the use of BMF assessment as a surrogate marker for clinical benefit with JAK inhibitors.

Phase 1 trial of navitoclax and sorafenib in patients with relapsed or refractory solid tumors with hepatocellular carcinoma expansion cohort

Navitoclax (ABT-263) is an oral BCL2 homology-3 mimetic that binds with high affinity to pro-survival BCL2 proteins, resulting in apoptosis. Sorafenib, an oral multi kinase inhibitor also promotes apoptosis and inhibits tumor angiogenesis. The efficacy of either agent alone is limited; however, preclinical studies demonstrate synergy with the combination of navitoclax and sorafenib. In this phase 1 study, we evaluated the combination of navitoclax and sorafenib in a dose escalation cohort of patients with refractory solid tumors, with an expansion cohort in hepatocellular carcinoma (HCC). Maximum tolerated dose (MTD) was determined using the continual reassessment method. Navitoclax and sorafenib were administered continuously on days 1 through 21 of 21-day cycles. Ten patients were enrolled in the dose escalation cohort and 15 HCC patients were enrolled in the expansion cohort. Two dose levels were tested, and the MTD was navitoclax 150 mg daily plus sorafenib 400 mg twice daily. Among all patients, the most common grade 3 toxicity was thrombocytopenia (5 patients, 20%): there were no grade 4 or 5 toxicities. Patients received a median of 2 cycles (range 1-36 cycles) and all patients were off study treatment at data cut off. Six patients in the expansion cohort had stable disease, and there were no partial or complete responses. Drug-drug interaction between navitoclax and sorafenib was not observed. The combination of navitoclax and sorafenib did not increase induction of apoptosis compared with navitoclax alone. Navitoclax plus sorafenib is tolerable but showed limited efficacy in the HCC expansion cohort. These findings do not support further development of this combination for the treatment of advanced HCC. This phase I trial was conducted under ClinicalTrials.gov registry number NCT01364051.

Clinical advances in TNC delivery vectors and their conjugate agents

Tenascin C (TNC), a glycoprotein that is abundant in the tumor extracellular matrix (ECM), is strongly overexpressed in tumor tissues but virtually undetectable in most normal tissues. Many TNC antibodies, peptides, aptamers, and nanobodies have been investigated as delivery vectors, including 20A1, α-A2, α-A3, α-IIIB, α-D, BC-2, BC-4 BC-8, 81C6, ch81C6, F16, FHK, Ft, Ft-NP, G11, G11-iRGD, GBI-10, 19H12, J1/TN1, J1/TN2, J1/TN3, J1/TN4, J1/TN5, NJT3, NJT4, NJT6, P12, PL1, PL3, R6N, SMART, ST2146, ST2485, TN11, TN12, TNFnA1A2-Fc, TNfnA1D-Fc, TNfnBD-Fc, TNFnCD-Fc, TNfnD6-Fc, TNfn78-Fc, TTA1, TTA1.1, and TTA1.2. In particular, BC-2, BC-4, 81C6, ch81C6, F16, FHK, G11, PL1, PL3, R6N, ST2146, TN11, and TN12 have been tested in human tissues. G11-iRGD and simultaneous multiple aptamers and arginine-glycine-aspartic acid (RGD) targeting (SMART) may be assessed in clinical trials because G11, iRGD and AS1411 (SMART components) are already in clinical trials. Many TNC-conjugate agents, including antibody-drug conjugates (ADCs), antibody fragment-drug conjugates (FDCs), immune-stimulating antibody conjugates (ISACs), and radionuclide-drug conjugates (RDCs), have been investigated in preclinical and clinical trials. RDCs investigated in clinical trials include 111In-DTPA-BC-2, 131I-BC-2, 131I-BC-4, 90Y-BC4, 131I81C6, 131I-ch81C6, 211At-ch81C6, F16124I, 131I-tenatumomab, ST2146biot, FDC 131I-F16S1PF(ab')2, and ISAC F16IL2. ADCs (including FHK-SSL-Nav, FHK-NB-DOX, Ft-NP-PTX, and F16*-MMAE) and ISACs (IL12-R6N and 125I-G11-IL2) may enter clinical trials because they contain components of marketed treatments or agents that were investigated in previous clinical studies. This comprehensive review presents historical perspectives on clinical advances in TNC-conjugate agents to provide timely information to facilitate tumor-targeting drug development using TNC.

Treatment of anemia in myelofibrosis: focusing on novel therapeutic options

INTRODUCTION

Myelofibrosis is a clonal myeloproliferative neoplasm associated with the proliferation of hematopoietic stem cells, increased bone marrow fibrosis, extramedullary hematopoiesis, hepatosplenomegaly, abnormal cytokine production, and constitutional symptoms. These and many other factors contribute to the development of anemia in myelofibrosis patients.

AREAS COVERED

This review summarizes novel and promising treatments for anemia in myelofibrosis including transforming growth factor-β inhibitors luspatercept and KER-050, JAK inhibitors momelotinib, pacritinib, and jaktinib, BET inhibitors pelabresib and ABBV-744, antifibrotic PRM-151, BCL2/BCL-XL inhibitor navitoclax, and telomerase inhibitor imetelstat.

EXPERT OPINION

Standard approaches to treat myelofibrosis-related anemia have limited efficacy and are associated with toxicity. New drugs have shown positive results in myelofibrosis-associated anemia when used alone or in combination.

Targeting accelerated pulmonary ageing to treat chronic obstructive pulmonary disease-induced neuropathological comorbidities

Chronic obstructive pulmonary disease (COPD) is a major incurable health burden, ranking as the third leading cause of death worldwide, mainly driven by cigarette smoking. COPD is characterised by persistent airway inflammation, lung function decline and premature ageing with the presence of pulmonary senescent cells. This review proposes that cellular senescence, a state of stable cell cycle arrest linked to ageing, induced by inflammation and oxidative stress in COPD, extends beyond the lungs and affects the systemic circulation. This pulmonary senescent profile will reach other organs via extracellular vesicles contributing to brain inflammation and damage, and increasing the risk of neurological comorbidities, such as stroke, cerebral small vessel disease and Alzheimer's disease. The review explores the role of cellular senescence in COPD-associated brain conditions and investigates the relationship between cellular senescence and circadian rhythm in COPD. Additionally, it discusses potential therapies, including senomorphic and senolytic treatments, as novel strategies to halt or improve the progression of COPD.

ACVR1: A Novel Therapeutic Target to Treat Anemia in Myelofibrosis

Activin receptor type I (ACVR1) is a transmembrane kinase receptor belonging to bone morphogenic protein receptors (BMPs). ACVR1 plays an important role in hematopoiesis and anemia via the BMP6/ACVR1/SMAD pathway, which regulates expression of hepcidin, the master regulator of iron homeostasis. Elevated hepcidin levels are inversely associated with plasma iron levels, and chronic hepcidin expression leads to iron-restricted anemia. Anemia is one of the hallmarks of myelofibrosis (MF), a bone marrow (BM) malignancy characterized by BM scarring resulting in impaired hematopoiesis, splenomegaly, and systemic symptoms. Anemia and red blood cell transfusions negatively impact MF prognosis. Among the approved JAK inhibitors (ruxolitinib, fedratinib, momelotinib, and pacritinib) for MF, momelotinib and pacritinib are preferably used in cytopenic patients; both agents are potent ACVR1 inhibitors that suppress hepcidin expression via the BMP6/ACVR1/SMAD pathway and restore iron homeostasis/erythropoiesis. In September 2023, momelotinib was approved as a treatment for patients with MF and anemia. Zilurgisertib (ACVR1 inhibitor) and DISC-0974 (anti-hemojuvelin monoclonal antibody) are evaluated in early phase clinical trials in patients with MF and anemia. Luspatercept (ACVR2B ligand trap) is assessed in transfusion-dependent MF patients in a registrational phase 3 trial. Approved ACVR1 inhibitors and novel agents in development are poised to improve the outcomes of anemic MF patients.

Evolving landscape of JAK inhibition in myelofibrosis: monotherapy and combinations

Myeloproliferative neoplasms (MPNs) are characterized by clonal myeloproliferation in 1 or more of the hematopoietic stem cell lineages. Primary myelofibrosis (MF), post-polycythemia vera MF, and post-essential thrombocythemia MF have the worst prognosis and are characterized by the presence of cytokine-mediated symptom complex, splenomegaly, progressive marrow failure, and clonal instability, leading to leukemic transformation. The key therapeutic aims encompass the management of symptoms, splenomegaly, and anemia and the improvement of survivals. These therapeutic aims have evolved with the availability of Jak inhibitors and novel agents, making disease modification potentially achievable. Novel agents may potentially target MPN stem cells, epigenetic alterations, signaling pathways, and apoptotic pathways. In this case-based review, we outline our approach to the management of MF and discuss the therapeutic landscape of MF, highlighting the utility of Jak inhibitors and novel Jak inhibitor-based combinations.

Pharmacological modulation of vascular ageing: A review from VascAgeNet

Vascular ageing, characterized by structural and functional changes in blood vessels of which arterial stiffness and endothelial dysfunction are key components, is associated with increased risk of cardiovascular and other age-related diseases. As the global population continues to age, understanding the underlying mechanisms and developing effective therapeutic interventions to mitigate vascular ageing becomes crucial for improving cardiovascular health outcomes. Therefore, this review provides an overview of the current knowledge on pharmacological modulation of vascular ageing, highlighting key strategies and promising therapeutic targets. Several molecular pathways have been identified as central players in vascular ageing, including oxidative stress and inflammation, the renin-angiotensin-aldosterone system, cellular senescence, macroautophagy, extracellular matrix remodelling, calcification, and gasotransmitter-related signalling. Pharmacological and dietary interventions targeting these pathways have shown potential in ameliorating age-related vascular changes. Nevertheless, the development and application of drugs targeting vascular ageing is complicated by various inherent challenges and limitations, such as certain preclinical methodological considerations, interactions with exercise training and sex/gender-related differences, which should be taken into account. Overall, pharmacological modulation of endothelial dysfunction and arterial stiffness as hallmarks of vascular ageing, holds great promise for improving cardiovascular health in the ageing population. Nonetheless, further research is needed to fully elucidate the underlying mechanisms and optimize the efficacy and safety of these interventions for clinical translation.

Top advances of the year: Myeloproliferative neoplasms

The rapid pace of drug development in hematology has led to multiple approvals for myelofibrosis (MF) and polycythemia vera (PV) in recent years. Moreover, there are many innovative agents and combinations being explored for myeloproliferative neoplasms (MPNs). In the past year, there have been several advances in MF, PV, and essential thrombocythemia. In MF, investigational approaches are focusing on strategies to optimize inhibition of signal transduction (including JAK inhibition), modify epigenetics, enhance apoptosis, target DNA replication, transform host immunity, and/or alter the tumor microenvironment. In PV, ropeginterferon alfa-2b has been introduced to the market in the United States, and data continue to accumulate to support the safety and efficacy of this treatment. Hepcidin mimesis is also emerging as a novel way to treat erythrocytosis. In essential thrombocythemia, ropeginterferon alfa-2b is being evaluated, as are therapies to modify epigenetics and inhibit CALR. The enhanced focus on MPNs brings hope that our field can improve morbidity and mortality in this group of diseases.

New era for myelofibrosis treatment with novel agents beyond Janus kinase-inhibitor monotherapy: Focus on clinical development of BCL-XL /BCL-2 inhibition with navitoclax

Myelofibrosis is a heterogeneous myeloproliferative neoplasm characterized by chronic inflammation, progressive bone marrow failure, and hepatosplenic extramedullary hematopoiesis. Treatments like Janus kinase inhibitor monotherapy (e.g., ruxolitinib) provide significant spleen and symptom relief but demonstrate limited ability to lead to a durable disease modification. There is an urgent unmet medical need for treatments with a novel mechanism of action that can modify the underlying pathophysiology and affect the disease course of myelofibrosis. This review highlights the role of B-cell lymphoma (BCL) protein BCL-extra large (BCL-XL ) in disease pathogenesis and the potential role that navitoclax, a BCL-extra large/BCL-2 inhibitor, may have in myelofibrosis treatment.

Targeting apoptosis dysregulation in myeloid malignancies - The promise of a therapeutic revolution

In recent years, the therapeutic landscape of myeloid malignancies has been completely revolutionized by the introduction of several new drugs, targeting molecular alterations or pathways crucial for leukemia cells survival. Particularly, many agents targeting apoptosis have been investigated in both pre-clinical and clinical studies. For instance, venetoclax, a pro-apoptotic agent active on BCL-2 signaling, has been successfully used in the treatment of acute myeloid leukemia (AML). The impressive results achieved in this context have made the apoptotic pathway an attractive target also in other myeloid neoplasms, translating the experience of AML. Therefore, several drugs are now under investigation either as single or in combination strategies, due to their synergistic efficacy and capacity to overcome resistance. In this paper, we will review the mechanisms of apoptosis and the specific drugs currently used and under investigation for the treatment of myeloid neoplasia, identifying critical research necessities for the upcoming years.