Biology subjects

Marcellino, B. K.

Publications and source records attributed to Marcellino, B. K..

4 recordsLinked to original sources

bioRxiv2026

TET2 and TP53 Mutations Cooperatively Modulate the Response to Inflammation to Promote Leukemic Transformation

TET2 is a commonly mutated gene in hematologic malignancies, including as an initiating event in clonal hematopoiesis (CH). Its mutation alters hematopoietic self-renewal, differentiation, and systemic inflammation responses. TP53 mutations co-occur with TET2 mutations and are also observed in patients with high-risk clonal hematopoiesis and hematologic malignancies. Using a murine model, we found that HSPCs with both mutations initially promoted a myeloproliferative phenotype. Over time these double mutant HSPCs acquire additional genomic alternations, leading to disease progression to acute leukemias including B-ALL. We observed enhanced inflammatory signatures at transformation and identified NLRP1 as a target of TP53 activation. Decreased response to an inflammatory cell death pathway in the setting of TP53 mutation allows cells to tolerate inflammatory stress. This pathway also modifies response to chemotherapies that induce protein translational stalling. Our results identify a hematopoietic stem cell stress response pathway with implications on adaptation to inflammation and chemotherapy tolerance. SignificanceTET2 and TP53 mutations co-operate leading to advanced hematologic malignancy. TET2 mutations promote an inflammatory environment and TP53 mutation supports tolerance to this inflammatory stress.

cancer biology↗

bioRxiv2025

Ontogeny Dictates Oncogenic Potential, Lineage Hierarchy, and Therapy Response in Pediatric Leukemia

Accumulating evidence links pediatric cancers to prenatal transformation events, yet the influence of the developmental stage on oncogenesis remains elusive. We investigated how hematopoietic stem cell developmental stages affect leukemic transformation, disease progression, and therapy response using a novel, humanized model of NUP98::NSD1-driven pediatric acute myeloid leukemia, that is particularly aggressive with WT1 co-mutations. Fetal-derived hematopoietic stem cells readily transform into leukemia, and WT1 mutations further enhance stemness and alter lineage hierarchy. In contrast, stem cells from later developmental stages become progressively resistant to transformation. Single-cell analyses revealed that fetal-origin leukemia stem cells exhibit greater quiescence and reliance on oxidative phosphorylation than their postnatal counterparts. These differences drive distinct therapeutic responses, despite identical oncogenic mutations. In patients, onco-fetal transcriptional programs correlate with worse outcomes. By targeting key vulnerabilities of fetal-origin leukemia cells, we identified combination therapies that significantly reduce aggressiveness, highlighting the critical role of ontogeny in pediatric cancer treatment.

cancer biology↗

bioRxiv2024

Metabolic Adaptations To Acute Glucose Uptake Inhibition Converge Upon Mitochondrial Respiration For Leukemia Cell Survival

One hallmark of cancer is the upregulation and dependency on glucose metabolism to fuel macromolecule biosynthesis and rapid proliferation. Despite significant pre-clinical effort to exploit this pathway, additional mechanistic insights are necessary to prioritize the diversity of metabolic adaptations upon acute loss of glucose metabolism. Here, we investigated a potent small molecule inhibitor to Class I glucose transporters, KL-11743, using glycolytic leukemia cell lines and patient-based model systems. Our results reveal that while several metabolic adaptations occur in response to acute glucose uptake inhibition, the most critical is increased mitochondrial oxidative phosphorylation. KL-11743 treatment efficiently blocks the majority of glucose uptake and glycolysis, yet markedly increases mitochondrial respiration via enhanced Complex I function. Compared to partial glucose uptake inhibition, dependency on mitochondrial respiration is less apparent suggesting robust blockage of glucose uptake is essential to create a metabolic vulnerability. When wild-type and oncogenic RAS patient-derived induced pluripotent stem cell acute myeloid leukemia (AML) models were examined, KL-11743 mediated induction of mitochondrial respiration and dependency for survival associated with oncogenic RAS. Furthermore, we examined the therapeutic potential of these observations by treating a cohort of primary AML patient samples with KL-11743 and witnessed similar dependency on mitochondrial respiration for sustained cellular survival. Together, these data highlight conserved adaptations to acute glucose uptake inhibition in diverse leukemic models and AML patient samples, and position mitochondrial respiration as a key determinant of treatment success.

cancer biology↗

bioRxiv2024

The reparative immunologic consequences of stem cell transplantation as a cellular therapy for refractory Crohn's disease

BackgroundTreatment strategies for Crohns disease (CD) suppress diverse inflammatory pathways but many patients remain refractory to treatment. Autologous hematopoietic stem cell transplantation (SCT) has emerged as a therapy for medically refractory CD. SCT was developed to rescue cancer patients from myelosuppressive chemotherapy but its use for CD and other immune diseases necessitates reimagining SCT as a cellular therapy that restores appropriately responsive immune cell populations from hematopoietic progenitors in the stem cell autograft (i.e. immune "reset"). Here we present a paradigm to understand SCT as a cellular therapy for immune diseases and reveal how SCT re-establishes cellular immunity utilizing high-dimensional cellular phenotyping and functional studies of the stem cell grafts. MethodsImmunophenotyping using CyTOF, single cell RNA sequencing (scRNA-seq) and T cell receptor (TCR) sequencing was performed on peripheral blood and intestinal tissue samples from refractory CD patients who underwent SCT. The stem cell graft from these patients was analyzed using flow cytometry and functionally interrogated using a murine model for engraftment. ResultsOur study revealed a remodeling of intestinal macrophages capable of supporting mucosal healing that was independently validated using multimodal studies of immune reconstitution events including CyTOF and scRNA-seq. Functional interrogation of hematopoietic stem cells (HSCs) using a xenograft model demonstrated that HSCs shape the timing of immune reconstitution, the selected reconstitution of specific cell lineages and potentially the clinical efficacy of SCT. ConclusionsThese studies indicate that SCT serves as a myeloid-directed cellular therapy re-establishing homeostatic intestinal macrophages that support intestinal healing and suggest refractory CD evolves from impairment of restorative functions in myeloid cells. Furthermore, we report heterogeneity among HSCs from CD patients which may drive SCT outcomes and suggests an unrecognized impact of CD pathophysiology on HSC in the marrow niche.

immunology↗