Pharmacological restriction of genomic binding sites redirects PU.1 pioneer transcription factor activity.

Transcription factor (TF) DNA-binding dynamics govern cell fate and identity. However, our ability to pharmacologically control TF localization is limited. Here we leverage chemically driven binding site restriction leading to robust and DNA-sequence-specific redistribution of PU.1, a pioneer TF pertinent to many hematopoietic malignancies. Through an innovative technique, 'CLICK-on-CUT&Tag', we characterize the hierarchy of de novo PU.1 motifs, predicting occupancy in the PU.1 cistrome under binding site restriction. Temporal and single-molecule studies of binding site restriction uncover the pioneering dynamics of native PU.1 and identify the paradoxical activation of an alternate target gene set driven by PU.1 localization to second-tier binding sites. These transcriptional changes were corroborated by genetic blockade and site-specific reporter assays. Binding site restriction and subsequent PU.1 network rewiring causes primary human leukemia cells to differentiate. In summary, pharmacologically induced TF redistribution can be harnessed to govern TF localization, actuate alternate gene networks and direct cell fate.

Exploring health disparities in diagnosing multiple myeloma.

BACKGROUND: Multiple myeloma (MM) is a plasma cell neoplasm, which accounts for 1-2% of cancers and approximately 17% of hematological malignancies in the United States each year. Fifty percent of patients with symptomatic MM have three or more primary care visits before being referred to a specialist, which is greater than any other cancer. A delay in the diagnosis of multiple myeloma has been shown to negatively impact the clinical course of the disease; patients with longer diagnostic intervals have been shown to experience shorter disease-free survival and higher rates of treatment-related complications. RESEARCH DESIGN AND METHODS: We performed a retrospective analysis of patients diagnosed with MM in our institution, to determine the time from the first detectable lab abnormality to the diagnosis of MM. RESULTS: We included 92 patients in this study. Fifty-two percent of patients had isolated anemia at the time of diagnosis. Twenty-nine percent of patients had a delay in diagnosis of ≥1 year, while 18% had a delay of ≥3 years. Nine patients in our cohort had anemia and an elevated serum total protein (31%). This group had the longest time to diagnosis with a median of 38 months. CONCLUSIONS: Our results did not show any difference in time to diagnosis by race, ethnicity, gender, or socioeconomic status.

A STAT3 Degrader Demonstrates Pre-clinical Efficacy in Venetoclax resistant Acute Myeloid Leukemia.

Acute myeloid leukemia (AML) is an aggressive hematologic malignancy that continues to have poor prognosis despite recent therapeutic advances. Venetoclax (Ven), a BCL2-inhibitor has shown a high response rate in AML; however, relapse is invariable due to mitochondrial dysregulation that includes upregulation of the antiapoptotic protein MCL1, a central mechanism of Ven resistance (Ven-res). We have previously demonstrated that the transcription factor STAT3 is upregulated in AML hematopoietic stem and progenitor cells (HSPCs) and can be effectively targeted to induce apoptosis of these aberrant cells. We now show that overexpression of STAT3 alone is sufficient to initiate a strong AML phenotype in a transgenic murine model. Phospho-proteomic data from Ven treated AML patients show a strong correlation of high total STAT3 and phospho-STAT3 [both p-STAT3(Y705) and p-STAT3(S727)] expression with worse survival and reduced remission duration. Additionally, significant upregulation of STAT3 was observed in Ven-res cell lines, in vivo models and primary patient samples. A novel and specific degrader of STAT3 demonstrated targeted reduction of total STAT3 and resulting inhibition of its active p-STAT3(Y705) and p-STAT3(S727) forms. Treatment with the STAT3 degrader induced apoptosis in parental and Ven-res AML cell lines and decreased mitochondrial depolarisation, and thereby dependency on MCL1 in Ven-res AML cell line, as observed by BH3 profiling assay. STAT3 degrader treatment also enhanced differentiation of myeloid and erythroid colonies in Ven-res peripheral blood mononuclear cells (PBMNCs). Upregulation of p-STAT3(S727) was also associated with pronounced mitochondrial structural and functional dysfunction in Ven-res cell lines, that were restored by STAT3 degradation. Treatment with a clinical-stage STAT3 degrader, KT-333 resulted in a significant reduction in STAT3 and MCL1 protein levels within two weeks of treatment in a cell derived xenograft model of Ven-res AML. Additionally, this treatment significant improvement in the survival of a Ven-res patient-derived xenograft in-vivo study. Degradation of STAT3 resulting in downregulation of MCL1 and improvements in global mitochondrial dysfunction suggests a novel mechanism of overcoming Ven-res in AML. Statement of Purpose: Five-year survival from AML is dismal at 30%. Our prior research demonstrated STAT3 over-expression in AML HSPC's to be associated with inferior survival. We now explore STAT3 over-expression in Ven-res AML, explain STAT3 mediated mitochondrial perturbations and describe a novel therapeutic strategy, STAT3 degradation to overcome Ven-res.

Immunophenotypic, genetic, and clinical characterization of adult T-cell leukemia/lymphoma: A single tertiary care center experience in the United States.

OBJECTIVES: Adult T-cell leukemia/lymphoma (ATLL) is an aggressive mature T-cell neoplasm caused by human T-cell lymphotropic virus type 1 (HTLV-1). Its most common immunophenotype is CD4+/CD7-/CD25+, although unusual immunophenotypes can occur and may lead to misdiagnosis. METHODS: The immunophenotypes, cytogenetics, molecular features, clinical presentations, treatment, and prognosis of 131 patients with ATLL were retrospectively studied in a large tertiary medical center in the United States. RESULTS: All cases showed loss of CD7 expression. While 82.4% of cases demonstrated CD4+, 17.6% exhibited unusual phenotypes, including CD4+/CD8+ (6.9%), CD4-/CD8- (2.3%), CD5- (3.1%), CD2-, and CD3-. The most common cytogenetics abnormalities included polysomy 3 (34.6%), translocation 1 (23.1%), and abnormalities found on chromosome 11 (30.8%) and chromosome 14 (26.9%). The common gene mutations identified by the next-generation sequencing study were TP53 (16.7%), TBL1XR1 (16.7%), EP300 (14.3%), and NOTCH1 (14.3%). TBL1XR1 mutation is associated with genetic instabilities. There was no significant difference between the clinical presentations of these 2 groups. CONCLUSIONS: Adult T-cell leukemia/lymphoma exhibits versatile immunophenotypic, cytogenetic, and molecular features. Simultaneous involvement of blood, lymph nodes, and other organs, along with hypercalcemia in a patient from an endemic area, necessitates HTLV-1 testing to avoid underdiagnosis of this dismal disease that might need aggressive chemotherapy followed by bone marrow transplant.

Testosterone therapy as a novel approach to the management of cytopenias in myelodysplastic neoplasms: a review of literature and case report.

PURPOSE: To explore the potential of testosterone therapy in managing cytopenias in myelodysplastic neoplasm and investigate the link between hypogonadism and hematologic malignancies. METHODS: A case of a patient with intermediate-risk myelodysplastic neoplasm and hypogonadism treated with testosterone replacement therapy is presented. Testosterone, prostate specific antigen, and erythropoietin levels were checked prior to therapy initiation and 3 months after. Blood counts were monitored over time. This is followed by a literature review of testosterone use in myelodysplastic neoplasm and the prevalence of hypogonadism in hematologic malignancies. RESULTS: The patient showed sustained improvement in anemia with testosterone therapy and reported subjective improvement in his weakness and fatigue. This improvement occurred even in the setting of an undetectable follow up erythropoietin level. His repeat prostate specific antigen levels remained low, while testosterone levels showed marked improvement. The literature review demonstrated positive response rates for testosterone in treating myelodysplastic neoplasm-related cytopenias, and showed a higher incidence of hypogonadism in hematologic malignancies. CONCLUSION: Our review suggests that the use of testosterone in low and intermediate-risk myelodysplastic neoplasm is underexplored and poses to have significant potential as a future therapeutic agent, after careful consideration of risks and benefits. In addition, the incidence of hypogonadism in myelodysplastic neoplasm and its potential impact on exacerbating cytopenias in myelodysplastic neoplasm warrants further investigation.

Socio-demographic determinants of myelofibrosis outcomes in an underserved center and the SEER national database.

The influence of demographic characteristics and social determinants on cancer outcomes is widely recognized in various malignancies but remains understudied in myelofibrosis (MF). This study aims to investigate social and demographic variables associated with MF survival. We retrospectively reviewed data of biopsy-proven MF patients from the Surveillance, Epidemiology and End Results (SEER) database (2000-2021) and Montefiore Medical Center (2000-2023), an underserved inner-city hospital. The SEER cohort included 5,403 MF patients and was predominantly Non-Hispanic (NH) White (82%) with a median age of 69 years. The age-adjusted incidence rate of MF was 0.32 cases per 100,000 person-years, increasing annually by 1.3% from 2000 to 2021. Two- and five- year overall survival rates were 69% and 42%, respectively. Worse cause-specific survival was associated with older age, male sex, and diagnosis before 2011 (year of Ruxolitinib approval). NH-Black ethnicity, unmarried status and lower median income were independent predictors of worse overall survival. The single-center analysis included 84 cases, with a median age of 66 years. NH-White patients comprised 37% of the sample, followed by NH-Black (28.5%). Two- and five- year overall survival rates were 90% and 61%, respectively, with NH-Black patients exhibiting the lowest median survival, although the difference was not statistically significant. Age was a significant predictor of worse survival in this cohort. NH-Black and Hispanic patients lived in areas with higher socioeconomic and demographic stress compared to NH-White patients. Overall, this study highlights the association of social and demographic factors with MF survival and emphasizes the need for equitable healthcare and further exploration of social-demographic factors affecting MF survival.

Immunotherapy-resistant acute lymphoblastic leukemia cells exhibit reduced CD19 and CD22 expression and BTK pathway dependency.

While therapies targeting CD19 by antibodies, chimeric antigen receptor T cells (CAR-T), and T cell engagers have improved the response rates in B cell malignancies, the emergence of resistant cell populations with low CD19 expression can lead to relapsed disease. We developed an in vitro model of adaptive resistance facilitated by chronic exposure of leukemia cells to a CD19 immunotoxin. Single-cell RNA-Seq (scRNA-Seq) showed an increase in transcriptionally distinct CD19lo populations among resistant cells. Mass cytometry demonstrated that CD22 was also decreased in these CD19lo-resistant cells. An assay for transposase-accessible chromatin with sequencing (ATAC-Seq) showed decreased chromatin accessibility at promoters of both CD19 and CD22 in the resistant cell populations. Combined loss of both CD19 and CD22 antigens was validated in samples from pediatric and young adult patients with B cell acute lymphoblastic leukemia (B-ALL) that relapsed after CD19 CAR-T-targeted therapy. Functionally, resistant cells were characterized by slower growth and lower basal levels of MEK activation. CD19lo resistant cells exhibited preserved B cell receptor signaling and were more sensitive to both Bruton's tyrosine kinase (BTK) and MEK inhibition. These data demonstrate that resistance to CD19 immunotherapies can result in decreased expression of both CD19 and CD22 and can result in dependency on BTK pathways.

Improving Unrelated Donor Equity: Assessing Mismatched Donor Opportunities with Real-World Data in a Minority-Predominant Cohort.

Recent advances in graft-versus-host disease (GVHD) prophylaxis including post-transplant cyclophosphamide (PTCy) and abatacept have significantly improved outcomes following HLA-mismatched allogenic hematopoietic stem cell transplantation (allo-HSCT) and have tremendous potential for reducing racial disparities in donor availability. A recent small study employing bone marrow as the source of stem cells showed similar outcomes after 5/8 versus 7/8 matches and is currently being tested in a larger study using peripheral blood stem cells. In this study, we examine real-world alternative donor HSCT options for a minority-predominant cohort in the Bronx, NY, focusing on the availability of lesser-matched (5/8 to 7/8) donors. Records of patients who underwent HLA typing at Montefiore Medical Center (2019 to 2022) were reviewed. The National Marrow Donor Program registry was queried to evaluate the availability of donors with at least 99% likelihood of HLA match at various levels (5/8, 6/8, 7/8, 8/8). Two hundred forty-one patients were included, 70% were non-White. Although the availability of ≥7/8 donors was less common in non-White patients, 100% of patients from each group had at least one or more 5/8 and 6/8 HLA-matched donors and more than 80% of these patients had >100 potential 5/8 and 6/8 HLA-matched donors. There was no statistical difference by race or ethnicity in the mean number of donors at 5/8 and 6/8 HLA-match levels. We demonstrate through real-world data that patients from diverse ethnic and racial backgrounds have access to 5/8 and 6/8 HLA-matched donors for allo-HSCT, potentially eliminating disparities in donor availability and allowing prioritization of other donor selection characteristics such as donor age, sex, ABO, and B leader matching. Further work is needed to study whether the use of mismatched donors offers a more potent graft-versus malignancy effect and optimal GVHD prophylaxis.

Impact of race and ethnicity on early mortality in multiple myeloma: a SEER analysis.

Over the past two decades, there have been significant advances in the treatment of multiple myeloma which has led to an improvement in overall survival (OS) (1,2). However, a notable proportion of patients continue to experience early mortality (EM), defined as two years from the time of diagnosis. This raises the possibility that improvements in myeloma survival have not extended equally to all groups. Using the latest data drawn from the Surveillance Epidemiology and End Results (SEER) database of patients in the United States spanning 2000-2019, we study impact of important sociodemographic factors on EM. Through regression modeling, we demonstrate that patients diagnosed from 2000-2005, of older age, male sex, and of certain racial minority status (non-Hispanic Black and Hispanic) have higher odds of EM. Of these factors, minority status contributed to worse 2-year overall survival as well. We evaluate whether income, as a surrogate to access to care, could potentially explain this finding, but find that race has a distinct relationship with EM that is not modified by income. This is further reinforced by subgroup analysis. After characterizing groups vulnerable to EM, we examine reasons for these disparities and potential avenues to address them.

Acute myeloid leukemias with JAK2/STAT mutations are associated with PD-L1 upregulation.

Even though overexpression of the immune checkpoint protein, programmed cell death ligand-1 (PD-L1), is observed in solid tumors, its expression patterns in acute myeloid leukemia remain understudied. As activation of the JAK/STAT pathway has been shown to enhance PD-L1 expression in preclinical models, we evaluated biopsies from AML patients with activating mutations in JAK2/STATs. PD-L1 expression was significantly upregulated in JAK2/STAT mutant cases when compared to JAK2 wildtype controls as demonstrated by PD-L1 immunohistochemistry staining and quantified using the combined positive score (CPS) system. There is significant overexpression of phosphorylated STAT3 expression in patients with oncogenic JAK2 activation and a positive correlation between p-STAT3 and PD-L1 expression. In conclusion, we demonstrate the CPS scoring system could be applied as a quantitative measure of PD-L1 expression in leukemias and that JAK2/STATs mutant AML can be potential candidates for checkpoint inhibitor trials.

A Metabolically Optimized, Noncytotoxic Low-Dose Weekly Decitabine/Venetoclax in MDS and AML.

PURPOSE: Venetoclax (VEN) added to the hypomethylating agents (HMA) decitabine or azacitidine is the new standard of care for elderly patients with acute myeloid leukemia (AML) and is being evaluated in myelodysplastic syndrome (MDS). Current dosing of HMA/VEN relies on leukemia suppression through cytotoxicity which also impacts normal hematopoiesis. A regimen using once-weekly low-dose decitabine (LDDec) has demonstrated activity in myeloid malignancies. To overcome the severe myelosuppression often seen with HMA/VEN, we evaluated a once-weekly dosing regimen of VEN and LDDec in elderly and/or frail patients who were felt less likely to tolerate severe myelosuppression. PATIENTS AND METHODS: This is a retrospective, single-center analysis of patients with AML, MDS, or chronic myelomonocytic leukemia treated with a once-weekly LDDec/VEN regimen. We also compare this regimen with a cohort treated with standard dosing HMA/VEN. RESULTS: In a retrospective cohort of 39 patients, the overall response rate for patients receiving LDDec/VEN for first-line AML and MDS was 88% and 64%, respectively. In patients with TP53 mutations, the composite complete response rate was 71% and the median overall survival was 10.7 months. When compared with 36 patients receiving standard dose HMA/VEN, the LDDec/VEN patients had a longer time on therapy (175 vs. 78 days; P = 0.014) and a trend toward a higher rate of transfusion independence (47% vs. 26%; P = 0.33). Neutropenic fever occurred in 31% of patients, with a median of one hospitalization at any point during treatment. CONCLUSIONS: This preliminary clinical experience, although retrospective, provides proof-of-activity of noncytotoxic DNA methyltransferase 1-targeting by allowing frequent, sustained drug exposure often not possible with standard HMA/VEN regimens.

Outcome of Stem Cell Transplantation in HTLV-1-Associated North American Adult T-Cell Leukemia/Lymphoma.

Adult T-cell leukemia/lymphoma (ATLL) remains challenging to treat and has dismal outcome. Allogeneic stem-cell transplantation (allo-SCT) has promising results, but data remain scarce. In this single-center retrospective analysis of 100 patients with ATLL from north America (67 acute, 22 lymphomatous), 17 underwent allo-SCT and 5 autologous SCT (ASCT), with a median follow-up of 65 months. Post-transplant 3-years relapse incidence (RI) and non-relapse mortality (NRM) were 51% and 37%, respectively, and 3-year progression-free survival (PFS) and overall survival (OS) were 31% and 35%, respectively. ASCT 1-year RI was 80% compared to 30% in allo-SCT (p = 0.03). After adjusting for immortal-time bias, allo-SCT had significantly improved OS (HR = 0.4, p = 0.01). In exploratory multivariate analysis, patients achieving first complete response and Karnofsky score ≥ 90 had significantly better outcomes, as did Black patients, compared to Hispanics, who had worse outcome. In transplanted patients, 14 died within 2 years, 4 of which ASCT recipients. Our data are the largest ATLL transplant cohort presented to date outside of Japan and Europe. We show that allo-SCT, but not ASCT, is a valid option in select ATLL patients, and can induce long term survival, with 40% of patients alive after more than 5 years.

Chimeric Antigen Receptor T-Cell Therapy for Patients With Multiple Myeloma-A Call for Equal Opportunity.

This Viewpoint examines the equity of US Food and Drug Administration approval and the clinical distribution of chimeric antigen receptor T-cell therapy for patients with multiple myeloma.

A Co-Management Model for Myeloid Malignancies That Evolved during the COVID-19 Pandemic.

INTRODUCTION: Myeloid malignancies are a heterogeneous group of clonal bone marrow disorders that are complex to manage in the community and therefore often referred to subspecialists at tertiary oncology referral centers. Many patients do not live in close proximity to tertiary referral centers and are unable to commute long distances due to age, comorbidities, and frailty. Interventions that minimize the travel time burden without compromising quality of care are an area of unmet need. We describe a cancer care delivery model for patients with myeloid malignancies that is built around telehealth and enables this vulnerable population access to care at an NCI-designated cancer center while receiving majority of their care close to home. METHODS AND MATERIALS: We report on a cohort of patients with myeloid malignancies who were co-managed by a general community oncologist and an academic leukemia subspecialist at Montefiore Einstein Cancer Center in New York. Patients were initially referred to our institute for a second opinion by community practices that are in partnership with Montefiore Health System, and initial visits were in-person or via telehealth. Treatment plans were made after discussion with patient's local community oncologist. Patients then continued to receive majority of their treatment and supportive care including transfusion support with their local oncologist, and follow-up visits were mainly via telehealth with the academic leukemia subspecialist. RESULTS: Our cohort of 12 patients had a median age of 81 years (range, 59-88 years). Patients remained on active treatment for a median time of 357 days (range, 154-557 days). Most of our patients had a performance status of ECOG 2 or higher. Three patients had myelodysplastic syndromes, 7 patients had acute myeloid leukemia, and 2 patients had myelofibrosis. The median number of hospitalizations over the total treatment time period was one. CONCLUSION: We demonstrate a shared academic and community care co-management model for the treatment of myeloid malignancies in elderly, frail patients using telehealth as a backbone with a very low hospitalization rate.

Lenalidomide and Eltrombopag for Treatment of Low- or Intermediate-Risk Myelodysplastic Syndrome: Result of a Phase II Clinical Trial.

PURPOSE: Thrombocytopenia is a serious complication of myelodysplastic syndromes (MDS) associated with an increased bleeding risk and worse prognosis. Eltrombopag (ELT), a thrombopoietin receptor agonist, can increase platelet counts and reverse anti-megakaryopoietic effects of lenalidomide (LEN) in preclinical studies. We hypothesized ELT would reduce the incidence of thrombocytopenia in MDS. PATIENTS AND METHODS: We conducted a Phase II multicenter trial of ELT and LEN in adult patients with low- or intermediate-1-risk MDS with symptomatic or transfusion-dependent anemia or thrombocytopenia (NCT01772420). Thrombocytopenic patients were started on ELT and subsequently treated with LEN after platelets were increased. Patients without thrombocytopenia were started on LEN monotherapy and treated with ELT if they became thrombocytopenic. RESULTS: Fifty-two patients were enrolled; mean age was 71 years (range 34-93). Overall response rate (ORR) in the intention-to-treat population was 35% (18/52). ELT monotherapy led to ORR of 33.3% (7/21), 29% achieving hematologic improvement (HI)-Platelets, and 24% bilineage responses. LEN monotherapy had 38% ORR (6/16) with all responders achieving HI-Erythroid. Fifteen patients received both ELT and LEN with ORR of 33.3%, 20% achieved HI-Erythroid, and 20% HI-Platelets with 13% bilineage responses. Median duration of response was 40 weeks for ELT (range 8-ongoing), 41 weeks (25-ongoing) for LEN, and 88 weeks (8.3-ongoing) for ELT/LEN. Non-hematologic grade 3-4 treatment-related adverse events were infrequent. Among patients on ELT, 2 had major bleeding events, 1 had a reversible increase in peripheral blasts, and 1 developed marrow fibrosis after 6 years on ELT. CONCLUSIONS: ELT and LEN are well tolerated and effective in achieving hematologic improvement in patients with low-/intermediate-risk MDS.