Citations

Introduction Spleen tyrosine kinase (SYK) is a non-receptor tyrosine kinase involved in immune signaling and has been implicated in tumor-intrinsic resistance to DNA-damaging therapies. Although SYK activity has been associated with poor outcomes in triple-negative breast cancer (TNBC), its role in resistance to combined radiotherapy and immune checkpoint blockade remains unclear. Methods SYK expression and clinical relevance were assessed across multiple breast cancer cohorts, including radiotherapy-treated datasets. Integrated transcriptomic analyses were used to characterize SYK-associated immune states. The functional effects of pharmacologic SYK inhibition were evaluated using in vitro assays and an immunocompetent bilateral 4T1 tumor model in female BALB/c mice treated with radiotherapy and PD-1 blockade. Treatment-associated immune remodeling was assessed by flow cytometry and transcriptomic profiling. Results Across multiple cohorts, elevated SYK expression, particularly in TNBC, was associated with inferior clinical outcomes and immune dysregulation. Pharmacologic SYK inhibition enhanced tumor responses to radiotherapy and PD-1 blockade at both irradiated and distant tumor sites. These effects were accompanied by coordinated remodeling of the tumor immune microenvironment, including suppression of neutrophil-associated signatures and reductions in immunosuppressive myeloid populations, including M2-like macrophages and myeloid-derived suppressor cells. Discussion Pharmacologic SYK inhibition enhances responses to radiotherapy and PD-1 blockade in preclinical TNBC models and is accompanied by remodeling of the immunosuppressive myeloid compartment. These findings support further investigation of SYK-targeted strategies to improve responses to combined radiotherapy and immune checkpoint blockade.

CD19-directed CAR T-cells (CTL019) can produce durable remissions in chronic lymphocytic leukemia (CLL), but therapeutic success depends on whether autologous T-cells expand, persist, and retain cytotoxic function after manufacturing. Failure of CLL T-cells is often attributed to exhaustion, although many dysfunctional CLL T-cells retain inflammatory cytokine production. We tested whether this paradox reflects immunosenescence, an aging-like program defined by costimulatory loss, DNA damage, inflammatory secretion, repertoire restriction, and proliferative arrest. In response-linked preinfusion CTL019 products, nonresponders and short partial responders had higher senescence and senescence-associated secretory phenotype (SASP) programs than the functional-responder group, comprising complete responders and partial responders with transformed disease. These programs were detectable before infusion and became more prominent during manufacture in susceptible products. They tracked with weak in vivo CAR T-cell expansion and were associated with inferior survival. Serum proteomics revealed a circulating, CLL-associated SASP-like inflammatory milieu in nonresponders. Flow cytometry and T-cell receptor (TCR) profiling showed that poor responders carried CD27⁻CD28⁻ and KLRG1⁺ CD8 T-cells at apheresis, lower product CD27, and reduced product TCR diversity. Research-manufactured CAR T-cells from treatment-naïve CLL samples displayed the same state, most prominently in CD4 CAR T-cells, with SA-β-gal, p16, p53, DNA damage, depletion of less-differentiated states, and senescence-enriched transcriptomes. Under repeated CD19 stimulation, CLL-derived products reached a proliferative ceiling, and p53-high products lost cytotoxic reserve. Ibrutinib improved proliferative fitness, attenuated senescence-associated features and SASP output in paired patient and direct-exposure assays, and enhanced CAR T-cell expansion in an ibrutinib-resistant CLL model. Together, these data identify immunosenescence as a measurable and functionally consequential barrier to CAR T-cell efficacy in CLL and a candidate for therapeutic modulation.

Abstract Anthracycline-induced cardiotoxicity (AIC) remains a dose-limiting complication of cancer treatment, often leading to irreversible heart failure, yet effective cardioprotective therapies remain limited. Graph-driven drug repurposing offers a rapid pathway to identify cardioprotective therapies, but different computational models often generate divergent candidate lists that exceed experimental validation capacity. We applied a novel "Union-then-Filter" framework to prioritize therapeutics for AIC using AI-based approaches and evaluated candidates in zebrafish models. Three state-of-the-art graph learning models (TxGNN, CompGCN, and RLR) were trained on the PrimeKG to generate an initial candidate pool. A Large Language Model (LLM) agent automated evidence synthesis across 4,286 PubMed abstracts for the top 50 drugs from each model. Candidates were stratified using dual decision criteria and filtered against existing clinical trials. The pipeline narrowed 150 initial candidates to four novel candidates: Cysteine, Dasatinib, Tranilast, and Tretinoin. Prospective in vivo validation was subsequently conducted using an adult AIC (aAIC) zebrafish model. Phenotypic screening via echocardiography revealed that Cysteine, Tranilast, and Tretinoin significantly restored ejection fraction (EF) (overall one-way ANOVA: \(\:F\left(\text{4,95}\right)=47.66,\:\:p<0.0001\); Tukey's post hoc: \(\:\:\:p<0.01\) for all three treatments vs. DOX+ control) and normalized cardiac remodeling markers in doxorubicin-treated subjects (Kruskal-Wallis: \(\:{\chi\:}^{2}\left(4\right)=17.21,\:\:p=0.0018\); Dunn’s post hoc: \(\:\:\:p<0.01\) for all three comparisons vs. DOX control). This study demonstrates the translational utility of an LLM-integrated AI pipeline for drug repurposing and highlights zebrafish AIC as an efficient bridge between in silico prediction and in vivo phenotypic validation in cardio-oncology.

Accumulation of DNA damage drives β-cell dysfunction, senescence, and death in type 1 and type 2 diabetes. Although α-cell dysfunction also contributes to disease pathology, α-cells remain remarkably resistant to senescence and increased cell death under diabetogenic stress. The mechanisms underlying these differential responses to diabetogenic stress, particularly differences in their DNA damage vulnerability, remain unclear. We demonstrate that replication introduces a window of genomic vulnerability in both α- and β-cells during neonatal growth, with α-cells exhibiting higher replication rates and DNA damage. We show that neonatal β-cells resolve DNA damage more efficiently during mitosis and favor error-free repair, whereas α-cells compensate for their greater DNA-damage vulnerability through increased cellular turnover. Using mouse models of overnutrition and diabetes, we show that β-cells exhibit greater vulnerability to terminal DNA damage and impaired repair capacity under diabetogenic stress, with compensatory replication amplifying this vulnerability. We demonstrate that developmental and postnatal epigenetic programs shape the differential DNA damage vulnerability of postnatal β- and α-cells. Loss of de novo DNA methyltransferase Dnmt3a in pancreatic progenitors selectively increases the DNA damage vulnerability of β-cells from neonatal growth through adulthood. Complementing this developmental process, enhancer analyses reveal lineage-specific DNA damage response regulatory landscapes that are remodeled in β-cells under metabolic stress. Collectively, our findings uncover novel developmental mechanisms that shape the distinct DNA damage responses of postnatal β- and α-cells during growth and diabetes. Article Highlights Mechanisms underlying the differential susceptibility of pancreatic β- and α-cells to diabetogenic stress remain unclear. We investigated whether replication, repair fidelity, and developmental epigenetic programs determine the vulnerability of postnatal β- and α-cells to DNA damage, a key driver of β-cell failure in diabetes. Replication introduces DNA damage vulnerability in both neonatal β- and α-cells, yet β-cells resolve damage more efficiently. Loss of DNA methyltransferase 3a in pancreatic progenitors selectively heightens β-cell DNA damage vulnerability that persists into adulthood. Moreover, diabetogenic stress preferentially compromises β-cell repair fidelity. These findings reveal how developmental programs shape β-cell resilience and may influence lifelong diabetes risk.

Our research uncovers a role for ATR in responding to ECM stiffness and promoting epithelial-to-mesenchymal transition (EMT) and metastasis. ATR, when deubiquitinated and upregulated by USP21 under enhanced ECM stiffness conditions, phosphorylates the nuclear protein SUN2, which promotes β-catenin nuclear translocation and EMT. ATM-mediated EMT promotes polymorphonuclear myeloid-derived suppressor cell recruitment and inhibits CD103 + dendritic cells, fostering an immunosuppressive tumor milieu. ATR inhibition disrupts this malignant cascade by promoting mesenchymal-to-epithelial transition to enhance antitumor immunity and mitigate metastases. Consistently, circulating HLA-DR + dendritic cells were also enhanced following treatment with the ATR inhibitor berzosertib in patients with therapeutically resistant early-stage breast cancer. Our data suggest that ATR-targeted therapy may be optimized by considering both DNA damage–dependent and EMT-inducing effects of ATR ATR promotes metastasis and immunosuppression through EMT process