6545 Background: TP53 -mutated AML is associated with early relapse and poor survival, highlighting the need to define p53-driven transcriptional programs that may reveal targetable therapeutic vulnerabilities. Systematic deconvolution of the TP53-associated transcriptome provides a critical framework to uncover dependencies associated with drug resistance. Methods: After IRB approval, 311 AML patients were screened; 93 (30%) with available NGS were included (32 TP53-mutated, 61 TP53-wild type). Bulk transcriptome data were available for 11 TP53+ and 13 TP53-WT cases. Overall survival was analyzed using Kaplan–Meier and multivariable Cox regression. Transcriptional modules predictive of TP53+ AML were identified using Random Forest and pathway enrichment via KEGG/Reactome with confirmation by ToppGene. Public single-cell RNA-seq datasets from the MIT Single Cell Portal were queried to assess whether low TP53 expression states recapitulate bulk TP53-mutated transcriptional programs. Results: OS was 168 and 624 days (d) in TP53+ and TP53 WT cases (HR = 4.2, p = 0.02). Only CK retained independent effect for OS (HR = 0.33, 95% CI = 0.13–0.82, p = 0.014) when accounting for TP53 mut status and age. TP53 mut status imprinted a deep transcriptomic signature (AUC = 0.94). Top upregulated genes included FHL2 (p = 4.0×10−6, FDR = 0.004), HMGA2 (p = 1.4×10−3, FDR = 0.02), ARHGEF12 (p = 5.2×10−3, FDR = 0.04), RYR3 (p = 2.1×10−3, FDR = 0.03), LRRC7 (p = 7.7×10−3, FDR = 0.05), ALDH1A1 (p = 1.4×10−3, FDR = 0.02). Top downregulated genes included CSF1 (p = 4.7×10−4, FDR = 0.007), CD34 (p = 1.2×10−3, FDR = 0.01). To uncover pathway-level shifts co-opted by TP53+ AML, we contrasted pathway-level projection against TP53 WT cases. Upregulated pathways included adhesion / stromal dependence (p = 0.0004; FDR = 0.0028), neurotrophin / calcium signaling / Ca2+-coupled survival (p = 0.0006, FDR = 0.0021). However, downregulated pathways included cytokine-cytokine receptor interaction (p = 4.7×10−4, FDR = 0.007) and myeloid differentiation (p = 1.2×10−3, FDR = 0.01) [Fig. 2]. Interestingly, in lineage-resolved single-cell reference, low TP53 GE was visually colocalized with perivascular/stromal cells exhibiting high FHL2 and THY1 (CD90) expression. This data reconfirms prior data suggesting that reduced TP53 function favors niche-adapted perivascular/MSC-like reprogramming (THY1-high) that protects “resistant AML clones” (Mizuno et al., ASH 2024). Conclusions: These findings unveil that TP53+ AML co-opts leukemic blasts toward a stromal-adhesive and neuronal-like state, allowing survival under metabolic and therapeutic stress. Reversing stromal adhesive / neuronal-like rewiring may attenuate TP53 + blasts hijacking on vascular niche that maintains relapse potential.

Introduction: Patients with aggressive hematologic malignancies have high rates of inpatient admissions. Specifically, patients receiving induction chemotherapy for acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) experience prolonged hospital stays due to the length of induction, transfusion dependence, and high risk of neutropenic fever. Traditional early discharge programs (EDP's) have been previously implemented to transition these patients to an outpatient setting prior to count recovery, but they have not provided care at home, rather relying on outpatient services and hospital readmissions. We developed a novel single-institution Hospital at Home (HaH) program with in-home biometric vitals monitoring, transfusion support, and inpatient-level medical care for patients with hematologic malignancies, including those undergoing acute leukemia induction. Methods: A HaH program was initiated at our tertiary academic cancer institute and safety-net hospital to allow early transition to a home environment with inpatient level services for patients with hematologic malignancies, including those receiving acute leukemia induction. Eligible patients were screened by inpatient Hematology, Hospital Medicine, and HaH teams; criteria for transition included absence of fever for 48 hours, less than daily blood transfusions, and a 24-hour caregiver. Residence distance within 45 minutes from the hospital was an initial criteria but was later waived as patients were able to transfer to an approved nearby hotel for ongoing care. Patients were monitored with a Biobeat biometric patch for continuous vitals monitoring (including blood pressure, heart rate, temperature, stroke volume, respiratory rate) that provided telemetry data in real time to the clinical team. Additionally, patients received at least twice daily visits by nursing staff, advance practice providers and/or physicians, which included phlebotomy, transfusion support, and IV infusions at home. We present data for 77 patients from 07/01/2024-06/30/2025 who were screened for the program. Results: 77 patients were screened for HaH and 36 (46.8%) were successfully transitioned to HaH. Reasons for enrollment failure were distance (36.6%), insurance (31.7%), patient acuity (14.6%), patient/family preference (14.6%), or multiple (4.9%). Of the 36 enrolled patients, 15 (41.7%) had ALL, 8 (22.2%) non-Hodgkin lymphoma (NHL), 7 AML (19.4%), 2 (5.5%) myeloma, 2 (5.5%) blast-phase chronic myeloid leukemia, and 2 (5.5%) had other hematologic malignancies. For the overall cohort, in-hospital length of stay (LOS) was 546 days, median inpatient LOS was 11 days (1-59), and median days enrolled in HaH was 5 (1-11). 183 inpatient bed-days were saved by HaH utilization (median 5 days per patient). Seven (19.4%) patients received platelet transfusions at home. Three (8.3%) patients were transferred to an approved hotel due to home distance outside the prespecified range. There were six (16.7%) unplanned readmissions, one for each of the following reasons: neutropenic fever (NF), cytokine release syndrome, hypoxia, abdominal pain, severe hypokalemia, and progressive leukemia. Thirty-day mortality was 0%. In the acute leukemia subgroup (n=24), in-hospital LOS was 409 days, median inpatient LOS was 16 days (1-59), and median days enrolled in HaH was 6 (1-11). 142 inpatient-bed days were saved by HaH utilization (median 6 days per patient). Four (16.7%) acute leukemia patients had unplanned readmissions, including one each for NF, hypoxia, severe hypokalemia, and progressive leukemia. Conclusions: This novel HaH program successfully provided inpatient-level care at home for patients with hematologic malignancies, including those undergoing acute leukemia induction. Continuous vitals monitoring devices were feasible and provided an additional measure of safety monitoring. Readmission rates were lower than those reported in other EDPs, and 30-day mortality was zero. Ongoing assessments will be conducted to identify additional eligible patients, determine rates of nosocomial infections at home, and improve access to inpatient-level care at home. This pilot project demonstrates a proof-of-concept for the safe delivery of high-level care for patients with hematologic malignancies, including acute leukemia induction, at home to improve bed capacity and allow increased access to care.

Background Immunotherapy is now an integral aspect of cancer therapy. Strategies employing adoptive cell therapy (ACT) have seen the establishment of chimeric antigen receptor (CAR)-T cells using peripheral blood lymphocytes as well as tumor-infiltrating lymphocytes (TILs) with significant clinical results. The bone marrow (BM) is an immunological niche housing T cells with specificity for previously encountered antigens, including tumor-associated antigens from certain solid cancers. This study sought to improve our understanding of tumor-specific BM T cells in the context of solid tumors by comparing them with TILs, and to assess whether there is a rationale for using the BM as a source of T cells for ACT against solid malignancies.Methods We used the murine B16 melanoma model examining both the endogenous OVA-specific T cell response using an OVA-specific tetramer or examining the OVA-specific response with OVA-specific transgenic CD8+ (OT-1) T cells. Specifically, we compared baseline intrinsic properties of TILs or BM T cells from tumor-bearing mice and their changes following adoptive transfer in the tumor and bone marrow (as well as other compartments when indicated).Results In tumor-bearing mice, endogenous tumor-specific T cells could be detected in the BM early in the course of tumor progression and possessed a more stem-cell-like and memory phenotype in an unsupervised cluster analysis compared with TILs which appeared more exhausted. The BM and tumor microenvironments significantly impact the fate of T cells. Naïve OT-1 transferred T cells acquired an exhausted phenotype in the tumor but maintained a more memory-like phenotype in the BM with tumor progression. Importantly, in a competitive transfer experiment, BM T cells infiltrated the tumor more efficiently than TILs, displayed a higher polyfunctionality with interleukin-2, interferon-γ, tumor necrosis factor-α production and showed greater persistence compared with TILs.Conclusions T cells from the BM appear superior to TILs as a source of cells for cellular therapy. They possess a memory-enriched phenotype and exhibit improved effector function, greater persistence within a tumor-bearing host, and the capacity for increased tumor infiltration. These data provide a foundation for further exploring the BM as a source of tumor-specific T cells for ACT in solid malignancies.

Abstract Purpose: Day 14 early bone marrow biopsies are routinely initiated to determine need for reinduction chemotherapy, but poorly predict true response and risk overtreatment. Day 21 (D21) bone marrow biopsies have been performed in the context of trials utilizing FLT3-targeted therapies in combination with induction chemotherapy (Stone et al. NEJM 2017). However, the utility of D21 bone marrow responses is not well defined. Methods: We retrospectively identified 26 newly diagnosed FLT3 mutant AML patients who underwent induction chemotherapy with midostaurin and Next Generation Sequencing (NGS) of bone marrow aspirate within a week of diagnosis. Results: 19/26 (73%) of patients had both D21 and response bone marrow biopsy. Of the remaining 7 patients, 4 patients did not have D21 bone marrow, 2 died of unrelated complications prior to response bone marrow, and 1 did not have recovery marrow available for assessment. Our cohort included 13 (50%) men with a median age of 57 years (range, 21 - 73 years). All patients had ECOG of 0 - 1. 96% of cases were de novo AML and 81% had normal cytogenetics. FLT3 ITD mutations were detected in 17 (65%) patients with a median FLT3 ITD ratio of 0.305 (range, 0.03 - 1) and median FLT3 VAF of 23.8% (range, 3.2 - 80.6%). 7 patients (26.9%) underwent additional allogeneic stem cell transplant. In the 19 patients evaluable for analysis, 13/13 (100%) patients with blast % ≤ 5 at D21 achieved a complete response (CR) based on recovery marrow. 4/6 (67%) patients with blast % > 5 at D21 which were considered to have residual disease based on pathology review (median blast % 11 (range, 6 - 17%) ultimately achieved a CR. The 2 patients that did not achieve a CR has a blast % of 29% and 9% on D21 marrow. Thus, the positive predictive value of D21 early bone marrow response corresponding with the response bone marrow was only 33% in our patient cohort. Of the 4 patients that did not have D21 marrow but had recovery marrows available for review, the CR rate was 100%. No other significant differences in initial disease characteristics were seen. There were no differences proportion of co-mutations in NPM1, DNMT3A, TP53, IDH2, and IDH1, and higher FLT3 ITD ratio nor FLT3 VAF corresponded with ability to clear D21 bone marrow. Additionally, there were no differences in minimal residual disease (MRD) and overall survival (OS) between the groups. Conclusions: Our study suggests early bone marrow response in the context of FLT3-mutant disease is not dependent on inherent disease characteristics and does not correspond to overall response to targeted induction chemotherapy. The utility of these marrows in is this population needs to be studied further in a larger cohort to better understand the clinical necessity to avoid unnecessary cost/procedures to patients and even more importantly unnecessary reinductions. Citation Format: Vincent Lok, Su Bin Hahn, Nikesh N. Shah, Daniel A. Kerr, Ivan M. Borrello, Eduardo M. Sotomayor, David M. Swoboda. Day 21 early bone marrow response does not offer high concordance with response bone marrow in the induction chemotherapy setting of FLT3 mutant acute myeloid leukemia [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3626.

The interplay between T-cell states of differentiation, dysfunction, and treatment response in acute myeloid leukemia (AML) remains unclear. Here, we leveraged a multimodal approach encompassing high-dimensional flow cytometry and single-cell transcriptomics and found that early memory CD8+ T cells are associated with therapy response and exhibit a bifurcation into two distinct terminal end states. One state is enriched for markers of activation, whereas the other expresses NK-like and senescence markers. The skewed clonal differentiation trajectory towards CD8+ senescence was also a hallmark indicative of therapy resistance. We validated these findings by generating an AML CD8+ single-cell atlas integrating our data and other independent datasets. Finally, our analysis revealed that an imbalance between CD8+ early memory and senescent-like cells is linked to AML treatment refractoriness and poor survival. Our study provides crucial insights into the dynamics of CD8+ T-cell differentiation and advances our understanding of CD8+ T-cell dysfunction in AML.-

PDF file - 70K, A, Serum levels of the indicated cytokines in patients with HNSCC and pleomorphic adenoma (non-cancer control). B, Comparison of serum TGF-beta1 levels in non-cancer controls and patients with HNSCC at the time of new diagnosis and at the time of recurrence. C, Comparison of serum levels of TGF-beta1 in patients with HPV-negative HNSCC at the time of diagnosis, and at two time points after the completion of treatment

Supplementary Figure 1 from Myeloid-Derived Suppressor Cells Promote Cross-Tolerance in B-Cell Lymphoma by Expanding Regulatory T Cells

Supplementary Table 1: Change in immune response by treatment group and HPV status for analyzed cohort n=32. Supplementary Table 2: Change in immune response by treatment group and HPV status for intent to treat cohort. Supplementary Table 3: Baseline Characteristics of the Intent to treat population. Supplementary Table 4: Pre and post changes in immune response outcomes between treatment arms (Intent to Treat cohort n=40). Supplementary Table 5 Correlations among changes in immune response outcomes in analyzed cohort. Supplementary Figure 1: Additional graphs of immune parameters. Supplementary Figure 2: Change in immune response by treatment group and HPV status. Supplementary Figure 3: Graphic relationship between immune response measures. Supplementary Figure 4 and 5: Gating strategy for the MDSC phenotype in this study defined as CD14+ or CD15+/CD33+/HLA-DRint/low/IL-4Ra+ as well as co-expression of CD14+/CD15+/ CD33+/HLA-DRint/low/IL-4Ra+. Supplementary Figure 6: Outliers from DTH assay are graphed on a larger scale for visualization. Supplementary Figure 7: Study Schema. Supplementary Figure 8: Correlation of BMI with change in primary immune response outcomes. Supplementary Figure 9: Correlations of BSA with change in primary immune response outcomes. Supplementary Figure 10: Correlations of BSA with change in primary immune response outcomes.

Supplementary figure 1. Gating strategy for MDSCs enumeration in the blood

Supplemental Figure 1. IQGAP1 levels correlate with disease progression and a poor prognosis;Supplemental Figure 2. IQGAP1 levels correlate with RAS pathway activation gene sets;Supplemental Figure 3. The impact of IQGAP1 WW peptide on cell cycle is reversible.

Supplementary figure 2. Tadalafil immunomodulatory properties in relation to body surface area, body mass index,or plasma volume

Supplementary figure 3. Tumor micro-environment modulation according to dose categories

PDF file - 256K, Clinical characteristics of patients with HNSCC

Supplementary Figure 5 from Myeloid-Derived Suppressor Cells Promote Cross-Tolerance in B-Cell Lymphoma by Expanding Regulatory T Cells

Supplementary Figure 2 from Myeloid-Derived Suppressor Cells Promote Cross-Tolerance in B-Cell Lymphoma by Expanding Regulatory T Cells

Supplementary methods. Description of the patients for the retrospective and the prospective study, list of inclusion and exclusion criteria, and detailed protocol for immunofluorescence analysis.

Supplementary Figure 3 from Myeloid-Derived Suppressor Cells Promote Cross-Tolerance in B-Cell Lymphoma by Expanding Regulatory T Cells

Despite recent advancement of treatment strategies in multiple myeloma (MM), patients with relapsed/refractory MM disease, particularly after triple-class refractoriness, continue to have poor prognosis. Chimeric antigen receptor (CAR-T) cells were developed and applied to improve outcomes in this setting, and two products, idecabtagene vicleucel and ciltacabtagene autoleucel, both targeting B-cell maturation antigen, have been approved by the Food and Drug Administration in the United States and European Medicines Agency in Europe. Both have shown unprecedented clinical outcomes with high response rate and prolonged progression-free survival and overall survival in this patient population with grim prognosis. Currently, further investigations are ongoing for CAR-T targeting different tumor antigens such as G protein-coupled receptor, class C, group 5, member D or with different combinations of intracellular signaling domains, as well as fourth-generation CAR-T with antigen-unrestricted inducible cytokines. Although CAR-T therapies hold hopes and enthusiasm from the myeloma community, several hurdles remain before these treatments become available for all patients in need. These barriers include CAR-T-cell manufacturing availability, access to administering centers, financial cost, caregivers' availability, and socioeconomic and racial disparities. Expanding clinical trial eligibility criteria and real-world data collection and analysis is crucial to understand the efficacy and safety of CAR-T in the patient cohort who tends to be excluded from current trials.

supplementary tables 1-5. Suppl.table 1: Retrospective case-control study: Patient characteristics: overall and by recurrence status; Suppl.table 2: Prospective Tadalafil study: Patients and tumor characteristics according to study arms; Suppl.table 3: Adverse Events (AE)by study arm; Suppl.table 4: Logistic regression analyses on the retrospective case-control study; Suppl.table 5: Effect of Tadalafil on blood CD4/CD8 ratio