Citations

e16017 Background: Pancreatic ductal adenocarcinoma (PDAC) is the most common form of pancreatic cancer and remains one of the deadliest malignancies worldwide, largely due to late-stage diagnosis. Early-stage PDAC is frequently asymptomatic, limiting opportunities for timely detection and intervention. We aimed to develop prognostic models using routinely acquired pre-diagnostic clinical data to identify individuals at high risk for PDAC prior to clinical manifestation. Methods: We conducted a retrospective study of patients treated at Mayo Clinic sites in Rochester, MN; Phoenix, AZ; and Jacksonville, FL between January 2011 and February 2023. The cohort included 1,151 patients with PDAC and 3,745 noncancer controls. CT scans were standardized to axial abdominal acquisitions with slice thickness between 0.8–3.0 mm. Radiology reports were de-identified, normalized, and parsed into structured sections (Indications, Findings, Impression), with an additional pancreas-specific section aggregating pancreas-related sentences. Demographic and clinical variables, e.g., age, sex, race, etc., were encoded using a templated sentence representation. All textual inputs were embedded using a Sentence-BERT model. A multimodal deep learning survival model was developed to integrate CT imaging, radiology report embeddings, and demographic features. The model was trained using a negative log-likelihood loss to estimate patient-specific PDAC risk scores. Model performance was assessed using the concordance index (C-index). Internal validation included patients from MN and AZ sites, while external validation used the FL cohort. Results: We evaluated unimodal (imaging, text, and demographics) and multimodal inputs. Fusion of imaging, radiology report, and demographic features achieved the highest performance, with internal and external validation C-indices of 0.885 (95% CI, 0.856–0.908) and 0.751 (95% CI, 0.719–0.783), respectively. Subgroup analysis by tumor location demonstrated differential performance. For pancreatic head tumors, internal and external C-indices were 0.916 (95% CI, 0.841–0.960) and 0.778 (95% CI, 0.730–0.823). For pancreatic body tumors, C-indices were 0.954 (95% CI, 0.897–0.997) internally and 0.929 (95% CI, 0.897–0.953) externally. For pancreatic tail tumors, internal and external C-indices were 0.903 (95% CI, 0.830–0.974) and 0.789 (95% CI, 0.689–0.874). Conclusions: A multimodal deep survival model leveraging pre-diagnostic CT imaging, radiology report embeddings, and demographic data can effectively identify individuals at high risk for PDAC prior to clinical diagnosis. Differences in performance were observed across pancreatic head, body, and tail tumors. This approach highlights the potential of opportunistic cancer risk stratification from routine imaging to enable earlier detection and targeted intervention strategies.

Abstract Introduction Ultrasonic vaping devices like SURGE are marketed as safer alternatives to conventional coil-based electronic cigarettes like JUUL due to their lower operating temperatures. However, their impact on cardiovascular health has not been fully characterized. Methods Sprague–Dawley rats were exposed daily for 9 weeks to aerosol generated from SURGE, JUUL, or clean air. Heart rate variability was continuously monitored via implanted telemetry. Cardiac fibrosis was quantified using histological analysis. Temperature profiles of SURGE, JUUL, and Nautilus (a coil-based tank device) were recorded. Aerosol samples were analyzed for carbonyl compounds using high-performance liquid chromatography. Results Both SURGE and JUUL exposures significantly reduced heart rate variability (high frequency and total power) compared with air. JUUL exposure significantly increased cardiac fibrosis; SURGE showed a similar mean fibrosis level but greater variability, resulting in a non-significant difference. SURGE devices operated at lower peak temperatures (~131°C) than JUUL (~239°C) and Nautilus (~160–170°C). Despite having the lowest temperature, SURGE emitted higher levels of carbonyl compounds than JUUL, although still substantially lower than Nautilus. Conclusions Although SURGE operates without coils and at lower temperatures than coiled vaping devices, it generates higher levels of carbonyls than some coiled devices and impairs cardiac autonomic regulation, and it can cause cardiac fibrosis comparable with JUUL although with high variability; that is, SURGE does not reliably avoid the increase in fibrosis caused by conventional electronic cigarettes. These findings suggest that non-thermal mechanisms predominate in mediating cardiovascular toxicity associated with ultrasonic vaping, challenging the assumption that coil-free designs are inherently safer. Implications Despite its lower operating temperature and coil-free design, the SURGE ultrasonic vaping device impaired cardiac autonomic function and promoted fibrosis at a mean level comparable to that of JUUL. These findings challenge claims of reduced harm from coil-less vaping technologies and suggest that non-thermal mechanisms may drive toxicity. Regulatory evaluations should consider device emissions and physiological outcomes—not just hardware features. Physicians and policymakers should be aware that coil-less systems may still pose cardiovascular risks, and marketing these devices as inherently safer may mislead users and undermine tobacco harm reduction efforts.

Autoimmune diseases arise when B and T lymphocytes lose tolerance to self. Yet in most disorders, the underlying molecular determinants, including autoantibodies, epitopes and lymphocyte clones that drive tissue injury remain undefined. Rapid-onset obesity with hypothalamic dysfunction, hypoventilation and autonomic dysregulation (ROHHAD) is a rare and often fatal pediatric neuroendocrine syndrome with strong evidence of antigen-driven paraneoplastic autoimmunity, including association with the intracellular autoantigen ZSCAN1. However, the effector immune circuit and the epitope-level determinants operating within the hypothalamus and brainstem have remained unknown. To address this challenge in ROHHAD and more broadly in autoimmune disease, we developed the Autoimmune Epitope and immunoGlobulin/Immune-receptor identification System (AEGIS), an integrated framework that links immune repertoires to their cognate self-epitopes. AEGIS combines B cell and T cell receptor profiling from sites of tissue injury with high-resolution epitope mapping, direct sequencing of antigen-specific autoantibodies, in silico antibody-antigen folding, selection, and T cell antigen discovery. Applied to a deeply phenotyped child with ROHHAD, AEGIS revealed a compartmentalized, clonally restricted immune response in which brain-deposited IgG and expanded cerebrospinal fluid B cell and CD4 T cell clonotypes converged on shared ZSCAN1 epitopes, resolved to minimal determinants and peptide-MHC ligands. These findings provide a clone- and epitope-linked mechanistic map of ROHHAD autoimmunity and establish a generalizable framework for identifying candidate pathogenic clones and antigens across diverse autoimmune diseases.

Among patients with treatment-naive hepatocellular carcinoma, glass microsphere radiation segmentectomy before liver transplant achieved high rates of complete pathologic necrosis, which was positively associated with the number of optimized treatment parameter thresholds.

The major barrier to clinical translation of αCD137 immunotherapy is separating antitumor efficacy from hepatotoxicity driven by IFN-γ–producing CD8 T cells. We propose a strategy to limit toxicity by promoting contraction of excessively expanded CD8 T cells. We identify CD11c + KLRG1 + effector CD8 T cells (CD11c + T E ) as the primary source of IFN-γ, recirculating between blood and secondary lymphoid organs (SLOs), where they undergo apoptosis during contraction. We show that lymphotoxin β receptor (LTβR) signaling restrains this contraction. Mechanistically, lymphotoxin-expressing B cells activate LTβR in fibroblastic reticular cells (FRCs), suppressing apoptosis of CD11c + T E cells in the spleen and sustaining their systemic circulation and liver infiltration. Pharmacological LTβR blockade abrogates hepatotoxicity by reducing the accumulation of IFN-γ–producing CD11c + T E cells while preserving tumor-specific CD8 T cell responses. These findings identify LTβR as a key regulator of effector CD8 T cell persistence and support the use of LTβR antagonists to improve the safety of αCD137-based immunotherapy.

Abstract Medulloblastoma (MB) is one of the most prevalent malignant brain tumors in children, with tremendous cognitive and neuroendocrine disability among survivors. Group 3 (G3) MBs have poor overall survival at < 50%, higher frequency of metastasis, and no targeted therapies. Amplification of MYC and activation of TGFβ signaling are frequent in G3MB. Remarkably, some tumors have no reported mutations, suggesting roles for epigenetic mechanisms in driving disease. We have generated novel humanized models for G3MB by transducing neuroepithelial stem cells (NESC) derived from human induced pluripotent stem (iPSC) cells with TGFβ effectors alone and/or in combination with MYC, prioritizing combinations observed in patients. We determined that both MYC and TGFβ effectors drove tumor formation in vivo with the combination driving more aggressive tumors and higher frequency of metastasis. NESC-derived tumors clustered with human G3/G4MB, indicating our models recapitulated human disease. To decipher mechanisms of resistance, we integrated CUT&RUN for MYC genomic localization and histone PTMs with RNA-sequencing and discovered MYC-bound neural developmental genes repressed in MYC and TGFβR1-driven lines. Further interrogation identified JARID1B, a MYC binding partner, as a regulator of many of these repressed neural genes. We postulate that deregulation of MYC and context-specific targeting to the chromatin template culminates in transcriptional alterations that promote aggressive G3MB. To further investigating therapeutic vulnerabilities, we have performed a in vivo whole genome CRISPRi screen to reveal important drivers of malignancy, one of the first of it’s kind in brain tumors. We are functionally validating key candidate sgRNAs that were differentially significant in primary tumors and may also have key roles in driving metastasis. Excitingly, many sgRNAs identified from the screen were chromatin modifiers and may be important co-factors of MYC-mediated regulation on the epigenome. Collectively, our studies provide a critical framework for understanding mechanisms of resistance and the epigenetic landscape of MYC- and TGFβ-driven MB.

TPS646 Background: SSTR-targeted RPT has transformed the treatment landscape for NETs, significantly improving clinical outcomes in phase 3 studies versus other targeted therapies. Nevertheless, disease progression and renal toxicity after treatment highlight the need for further improvement. Use of the α-emitter 225 Ac as the radioactive component has shown promising results in clinical studies: initial data from ACTION-1 suggest promising efficacy for RYZ101, a first-in-class, highly potent α-emitting RPT, in patients with SSTR+ GEP-NETs progressing after 2–4 cycles of 177 Lu-somatostatin analogs. RYZ401 is a cyclic 6-amino acid SSTR-targeting peptide agonist conjugated to a DOTA chelator bound to 225 Ac. Preclinical data have shown an improved therapeutic window versus DOTATATE. RYZ401 has the potential to deliver higher radiation doses to tumors, with improved renal clearance and lower kidney absorbed dose, potentially eliminating the need for amino acid infusion. Methods: RYZ401-101 is a global, multicenter, phase 1, first-in-human, dose-escalation/-expansion study designed to determine the recommended phase 2 dose (RP2D) and optimal treatment regimen, safety and tolerability, and preliminary efficacy of RYZ401 in patients with NETs and other selected solid tumors expressing SSTRs. Key eligibility criteria: histologically confirmed metastatic or unresectable well-differentiated NETs; WHO grade 1–3 (Ki-67 ≤55%); ≥1 SSTR PET-positive measurable lesion; and disease progression after ≥1 prior treatment line. In dose escalation, 6–18 patients will receive escalating doses of RYZ401 (2.0–11.1 MBq IV Q6W × 2–4 cycles); no amino acid co-infusion is planned. In dose expansion, approximately 80 patients will receive RYZ401 at the RP2D, 40 patients with well-differentiated GEP-NETs (cohort A) and 40 with other SSTR+ tumors including non-GEP-NETs (cohort B). Primary endpoints: dose-limiting toxicities in weeks 1–4 of treatment (dose escalation) and safety (dose expansion). Secondary endpoints: safety, pharmacokinetics, and efficacy outcomes (dose escalation and expansion). RYZ401 dosimetry will be evaluated in a sub-study of 10−16 patients. Enrollment is ongoing in the USA. Clinical trial information: NCT07165132 .

TPS611 Background: GPC3 is an oncofetal protein expressed in up to 75% of hepatocellular carcinomas (HCCs) and associated with poor prognosis. Its selective expression in tumor and not in normal tissue makes it a promising target for radiopharmaceutical imaging and therapy (theranostics). The GPC3-selective diagnostic RYZ811 ([ 68 Ga]Ga-RAYZ-8009) and therapeutic α particle-emitting RYZ801 ([ 225 Ac]Ac-RAYZ-8009) are a theranostic pair. Previous studies show high uptake of RYZ811 in intrahepatic and extrahepatic HCCs, with low normal liver background uptake. In GPC3+ HCC mouse models, single administrations of RYZ801 significantly inhibited tumor growth. Methods: RYZ801-101 is a single-arm, open-label, phase 1/1b study of RYZ811 and RYZ801 in previously treated patients with GPC3+ unresectable HCC. The study has two parts: dose escalation (part 1) and dose expansion (part 2). Each part consists of two stages: RYZ811 imaging and RYZ801 treatment. The aim of imaging is to determine if RYZ811 safely and adequately identifies patients with GPC3+ tumors. The aim of treatment is to determine the safety, pharmacokinetics (PK), recommended phase 2 dose (RP2D; part 1), and preliminary antitumor activity (part 2) of RYZ801. Key eligibility criteria are: confirmed HCC; Barcelona Clinic Liver Cancer stage B or C; Child-Pugh A; ≥1 RECIST v1.1-measurable lesion (treatment stage); and disease progression after ≥1 systemic therapy in part 1 and 1 prior line in part 2. In part 1, approximately 60 patients will receive RYZ811 (185 MBq) in the imaging stage; up to 30 of these will receive escalating doses of RYZ801 (2.6–5.5 MBq × 4 doses) in the treatment stage. In part 2, approximately 80 patients will receive RYZ811 (185 MBq) in the imaging stage; up to 40 of these will receive RYZ801 at the RP2D in the treatment stage. Primary RYZ811 objectives are to assess the safety/tolerability and biodistribution of RYZ811. Secondary objectives are to determine absorbed doses (ADs) to organs and tissues and any association between RYZ811 uptake and RYZ801 efficacy. Primary RYZ801 objectives are to identify the RP2D and safety/tolerability of RYZ801. Secondary objectives are to assess PK, ADs to critical organs and tumors, and preliminary antitumor activity. Enrollment for Part 1 is ongoing in the USA. Clinical trial information: NCT06726161 .