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Key Points ift140 -deficient zebrafish exhibited phenotypes observed in mammals, including skeletal defects and kidney cysts. Beyond ciliogenesis, ift140 also regulated cell polarity and intracellular microtubule stability, potentially contributing to cystogenesis. Microhomology-mediated end joining–induced mosaic ift140 crispants enabled evaluation of cystogenesis in adult fish and F0-based screening for modifiers of kidney cysts. Background Genetic modifiers are believed to play an important role in the onset and severity of polycystic kidney disease, but identifying these modifiers has been challenging due to the lack of effective methodologies. Methods We generated zebrafish mutants of IFT140 , a skeletal ciliopathy gene and newly identified autosomal dominant polycystic kidney disease gene, to examine skeletal development and kidney cyst formation in larval and juvenile mutants. In addition, we used ift140 crispants, generated through efficient microhomology-mediated end joining–based genome editing, to compare phenotypes with mutants and conduct a pilot genetic modifier screen. Results ift140 mutants developed kidney cysts and bone defects similar to those seen in mammalian models. ift140 crispants recapitulated mutant phenotypes while bypassing the early lethality of the mutants, enabling the analysis of kidney cyst formation in adult fish. In addition to cilia defects, we identified nonciliary phenotypes, including disrupted cell polarity and aberrant cytoplasmic microtubule stabilization in kidney epithelial cells, as potential contributors to ift140 -associated cystogenesis. The ability to detect ift140 -associated kidney cysts with ease allowed us to develop an F0-based genetic screen to identify potential protective modifiers. A pilot screen of 16 genes previously implicated in dysregulated signaling pathways in autosomal dominant polycystic kidney disease revealed both known and novel modifiers, including mtor and ulk1a . We further found that inhibition of mtor and ulk1a reversed both cilia-related and non–cilia-related abnormalities in the kidney. Conclusions By establishing a zebrafish model of ift140 -associated cystic kidney disease, we recapitulated ift140 ’s ciliary role and uncovered a nonciliary function in kidney cystogenesis. Importantly, we demonstrated the feasibility of using ift140 mosaic crispants to evaluate cystogenesis in adult fish and to perform F0-based screening for identifying genetic modifiers of kidney cysts.

ABSTRACTBackgroundPercutaneous transluminal angioplasty and stenting (PTAS) in patients with carotid stenosis may have potential effects on brain parenchyma. However, current studies on parenchymal changes are scarce due to the need for advanced imaging modalities. Consequently, the alterations in brain parenchyma following PTAS remain an unsolved issue.PurposeTo investigate changes to the brain parenchyma using magnetic resonance elastography (MRE).Study TypeProspective.Population13 patients (6 women and 7 men; 39 MRI imaging sessions) with severe unilateral carotid stenosis patients indicated for PTAS were recruited between 2021 and 2024.Field Strength/SequenceNoncontrast MRI sequences including MRE (spin echo) were acquired using 3 T scanners.AssessmentAll patients underwent MRE before (preprocedural), within 24 h (early postprocedural) and 3 months after (delayed postprocedural) PTAS. Preprocedural and delayed postprocedural ultrasonographic peak systolic velocity (PSV) was recorded. MRE stiffness and damping ratio were evaluated via neural network inversion of the whole brain, in 14 gray matter (GM) and 12 white matter (WM) regions.Statistical TestsStiffness and damping ratio differences between each pair of MR sessions for each subject were identified by paired sample t tests. The correlations of stiffness and damping ratio with stenosis grade and ultrasonographic PSV dynamics were evaluated by Pearson correlation coefficients. The statistical significance was defined as p < 0.05.ResultsThe stiffness of lesion side insula, deep GM, and deep WM increased significantly from preprocedural to delayed postprocedural MRE. Increasing deep GM stiffness on the lesion side was positively correlated with the DSA stenosis grade significantly (r = 0.609). The lesion side insula stiffness increments were positively correlated with PSV decrements significantly (r = 0.664).Data ConclusionRegional brain stiffness increased 3 months after PTAS. Lesion side stiffness was positively correlated with stenosis grades in deep GM and PSV decrements in the insula.Evidence Level2.Technical EfficacyStage 2.

SLC26A9 is a Cl - channel and electrogenic Cl - -HCO 3 ‑ exchanger found in several human epithelia, including the lung, intestine / GI tract, and kidney. SLC26 proteins are defined by a C-terminal, cytoplasmic sulfate transporter / anti-σ-domain (STAS). In mammals, several STAS domains have protein-protein interactions with the regulatory-region of CFTR (R-CFTR), the Cl - channel associated with cystic fibrosis. However, the functional consequences, i.e., regulatory effects (up/downregulation), of STAS-to-R-CFTR binding seem to differ by SLC26 member. Our prior work showed that the SLC26A9:CFTR interaction decreases SLC26A9 channel and exchange activity. If SLC26A9-STAS was replaced with SLC26A6-STAS, no inhibition of SLC26A9 conductance occurred when interacting with R-CFTR (PMID 19643730). Complete deletion of SLC26A9-STAS removed Cl - conductance. Thus, we hypothesized that a disordered loop within STAS is the likely interaction area, and therefore deleted this STAS-disordered loop (ΔLoop) to test this region’s functionality. We used a voltage clamp to measure Cl - currents (IV; conductance G calculated) in Xenopus laevis oocytes (n=10 / construct) injected with cRNA of ΔLoop and subcomponent areas of SLC26A9. Each construct contained a 3xFLAG tag such that stained oocytes from these constructs allowed determination of membrane expression. ΔLoop has three subregions: K/R rich, Middle, S/T rich. Both ΔLoop and ΔLoop(K/R) increase Cl - currents (and conductance) by 5x greater comparted to wild-type SLC26A9. Five amino acid extension of ΔLoop (N- or C-terminal) produces Cl - currents equivalent to ΔLoop deletion. However, 10 amino acid extension of ΔLoop (N- or C- direction) produces currents equivalent to WT-SLC26A9. Membrane localization indicates that ΔLoop and regional deletion constructs have similar membrane abundance to WT, while boundary deletions inhibit channel trafficking to the membrane. As ΔLoop(S/T) slightly increased conductance, the ordered S/T-rich motif [T 620 SVSYITFS 628 ] was examined for possible phosphorylation effects by serial alanine substitution. Each alanine substitution in the S/T-rich motif decrease SLC26A9 Cl - conductance vs WT-SLC26A9. However, for S623A the conductance decrease was due to minimal plasma membrane expression rather than apparent change of channel activity. Together these data suggest that the disordered loop is multifaceted and can maintain low conductance (autoinhibition) or by potential phosphorylation. As cystic fibrosis (CF) results from loss-of-function, trafficking or degradation mutations, the robust Cl - conductance from elimination of SLC26A9 autoinhibitory, disordered loop, presents an opportunity to supplement or replace Cl - conductance in CF tissues and potentially patients. R25-DK101405 This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.

Abstract TDP-43 pathology is a defining feature of Limbic-Predominant Age-Related TDP-43 Encephalopathy neuropathologic change (LATE-NC) and is frequently comorbid with Alzheimer’s disease neuropathologic change (ADNC). However, the molecular consequences of co-occurring LATE-NC and ADNC pathology (TDP-43, β-amyloid, and tau protein pathologies) remain unclear. Here, we conducted a comparative biochemical, molecular, and proteomic analysis of hippocampal tissue from 90 individuals spanning control, LATE-NC, ADNC, and ADNC+LATE-NC groups to assess the impact of cryptic exon (CE) inclusion, phosphorylated TDP-43 pathology (pTDP-43), and AD-related pathologies (β-amyloid, and tau) on the proteome. ADNC+LATE-NC cases exhibited the highest burden of CE inclusion as quantified by measuring the levels of known TDP-43 regulated CEs within eight transcripts: STMN2, UNC13A, ELAVL3, KALRN, ARHGAP32, CAMK2B, PFKP, and SYT7 . While CE levels correlated with pTDP-43 pathology, they were more strongly correlated with each other, suggesting that the molecular signature of CE inclusion may serve as a more sensitive measure of TDP-43 dysfunction than pTDP-43 pathology alone. Unbiased classification based on the relative abundance of these eight CEs stratified individual cases into low, intermediate, and high CE burden subtypes, largely independent of β-amyloid and tau pathology. Proteome-wide correlation analysis revealed a bias toward reduced protein levels from genes harboring TDP-43-regulated CEs in cases with high cumulative CE burden. Notably, proteins significantly decreased under high CE burden included canonical STMN2, ELAVL3, and KALRN, as well as kinesin proteins that are genetically associated with amyotrophic lateral sclerosis. Co-expression network analysis identified both shared and distinct biological processes across CE subtypes and pathways associated with pTDP-43, tau, β-amyloid pathologies, and CE accumulation in the hippocampus. Protein modules associated with TDP-43 loss of function were prioritized by integrating proteomic data from TDP-43–depleted human neurons with the hippocampal co-expression network. Specifically, we observed decreased endosomal vesicle, microtubule-binding, and synaptic modules, alongside an increase in RNA-binding modules. These results provide new insights into the proteomic impact of CE burden across the spectrum of LATE and AD pathological severity, highlighting the molecular consequences of TDP-43 dysfunction in neurodegenerative disease

TPS11580 Background: Gastrointestinal stromal tumor (GIST) is the most common sarcoma of the gastrointestinal tract. KIT and platelet-derived growth factor receptor α ( PDGFRA ) mutations remain the key oncogenic drivers in the majority of patients with advanced GIST, with acquired secondary drug-resistant mutations contributing to the heterogeneity and complexity of the disease. The diversity of these resistance mutations allows escape from standard-of-care tyrosine kinase inhibitor (TKI) therapy, creating an unmet need for novel therapies that inhibit all clinically relevant GIST-driving mutations. DCC-3009 is an investigational, highly potent, and selective switch-control KIT and PDGFRA inhibitor designed to act against known clinically relevant primary and secondary GIST-driving mutations while limiting off-target effects. Preclinical data showed that DCC-3009 has strong antitumor effects in xenograft models driven by resistant KIT mutations, optimized solubility and oral bioavailability, and low risk of cytochrome P450 inhibition. Here, we describe an ongoing phase 1/2 study evaluating DCC-3009 as a monotherapy in patients with advanced GIST. Methods: This study is a multicohort, open-label, phase 1/2 trial evaluating the safety, tolerability, and efficacy of DCC-3009 in patients with advanced GIST (NCT06630234). This trial uses a modular approach, with each module defined according to the therapy (DCC-3009 alone or in combination with other anticancer agents) and divided into 2 parts (dose escalation and dose expansion). For inclusion in the DCC-3009 monotherapy dose escalation, adult patients (≥18 years) must have histologically or cytologically confirmed advanced GIST with documented KIT or PDGFRA mutation and progression on or intolerance to at least 1 approved TKI regimen in the advanced setting (imatinib if KIT -mutant). Patients must have at least 1 measurable lesion per modified Response Evaluation Criteria in Solid Tumors version 1.1 (mRECIST v1.1) and an Eastern Cooperative Oncology Group Performance Status of 0 or 1 at screening. Exclusion criteria include receiving systemic anticancer therapy (encompassing investigational agents) within 14 days or less than 5 half-lives, radiotherapy within 14 days prior to first dose of study drug, prior or concurrent malignancy requiring treatment or expected to need treatment for active cancer, known allergy or hypersensitivity to the study drug components or any of its excipients, and impaired oral absorption or malabsorption syndrome. Enrolled patients across monotherapy dose escalation will receive DCC-3009 orally in 28-day cycles. The primary outcome measures for monotherapy dose escalation include safety assessment. Secondary outcome measures include objective response rate, duration of response, and progression-free survival by mRECIST v1.1, as well as overall survival and pharmacokinetics. Clinical trial information: NCT06630234 .

Abstract Ischemic cardiomyopathy (ICM) is a leading cause of heart failure characterized by extensive remodeling of the cardiac extracellular matrix (ECM). While initially adaptive, ECM deposition following ischemic injury eventually turns maladaptive, promoting adverse cardiac remodeling. The strong link between the extent of fibrosis and adverse clinical outcomes has led to growing interest in ECM targeted therapies to prevent or reverse maladaptive cardiac remodeling in ICM; yet, the precise composition of the ECM in ICM remains poorly defined. In this study, we employed a sequential protein extraction enabled by the photocleavable surfactant Azo to enrich ECM proteins from left ventricular tissues of patients with end-stage ICM (n=16) and nonfailing donor hearts (n=16). High-resolution mass spectrometry-based quantitative proteomics identified and quantified over 6,000 unique protein groups, including 315 ECM proteins. We discovered significant upregulation of key ECM components, particularly glycoproteins, proteoglycans, collagens, and ECM regulators. Notably, LOXL1, FBLN1, and VCAN were among the most differentially expressed. Functional enrichment analyses revealed enhanced TGFβ signaling, integrin-mediated adhesion, and complement activation in ICM tissues, suggesting a feedback loop driving continued ECM deposition in the end-stage failing heart. Together, our findings provide a comprehensive proteomic landscape of ECM alterations in the end-stage ICM myocardium and identify promising molecular targets for therapeutic intervention.

10556 Background: The coexistence of interstitial lung diseases (ILD) and lung cancer (LC) presents a clinical challenge. ILD, including idiopathic pulmonary fibrosis (IPF) and non-IPF entities, is associated with an elevated risk of LC. However, the clinical features, treatment patterns, and survival outcomes of ILD-LC, especially IPF-LC, remain underexplored. We aimed to comprehensively evaluate survival outcomes and risk factors for mortality of ILD-LC patients based on a real-world long-term clinical cohort. Methods: A total of 1,341 eligible patients for this study were drawn from the Epidemiology and Genetics of Lung Cancer research program database (Mayo Clinic) including 96 IPF-LC, 111 Non-IPF ILD-LC, 99 ILD-only, and 1,035 propensity-matched LC-only patients (Controls). Data were collected on demographics, comorbidities, tumor features, treatment, and patient outcomes. Survival analyses used Kaplan-Meier methods; risk factors were assessed via Cox Proportional Hazards models. All comparisons reported below were statistically significant with p-values≤0.001 unless specified. Results: Among the 20,470 primary LC patients who were diagnosed from 1997 through 2016 and followed to 2021, 207 (1.0%) had ILD-LC, of which 96 (46.4%) had IPF. Comparing to Controls, ILD-LC patients were 4 years older at the time of LC diagnosis, 63.8% (vs. 52.8%) male, had a higher rate of former smokers (60.4% vs. 47.3%), a lower proportion of adenocarcinoma (37.7% vs. 57.5%), and a higher proportion of squamous cell (28.0% vs. 20.3%) and small cell carcinoma (13.5% vs. 8.4%). Although no significant differences in either LC stage or grade, ILD-LC patients had a significantly higher mortality rate (90.3% vs. 78.8%), particularly among IPF-LC patients (97.9% vs. 83.8%). ILD-LC patients were less likely to undergo surgery or receiving pharmacological treatments (73.9% vs. 93.5%). The median 5-year overall survival rate (OS, months) were 49.5 for Controls, 35.2 for Non-IPF ILD-LC patients, and 15.9 for IPF-LC patients. Analysis of six most common comorbidities revealed that pulmonary hypertension was associated with worse OS in ILD-LC patients compared to those without it (11.9% vs. 20.1%, P < 0.05); however unexpectedly, hypertension in ILD-LC patients was associated with better OS (21.3% vs. 14.4%) and emphysema in IPF-LC patients with better OS (7.9% vs. 3.4%, P < 0.05) when compared to those without the two comorbidities, respectively. Conclusions: This study highlights the poorer survival outcomes in ILD-LC patients, particularly IPF-LC patients, emphasizing the need for further investigation into optimized therapies and comorbidity management. Our findings also call for attention to two unexpected associations of hypertension and emphysema, warranting in-depth research on the possible biological and physiological mechanisms.

Abstract Rationale Amikacin liposome inhalation suspension (ALIS), as part of a combination antibacterial regimen, is currently the only FDA-approved treatment for patients with refractory Mycobacterium avium complex lung disease (rMACLD). MAC is the most common cause of nontuberculous mycobacterial lung disease (NTMLD). A real-world evidence study demonstrated significant decreases in hospitalizations from baseline over a 12-month follow-up period following ALIS initiation; however, study conclusions were limited by the absence of a comparator arm. In this study, we compared healthcare resource utilization in US patients who initiated ALIS versus non-ALIS antibiotic treatment for possible rMACLD. Methods This was a retrospective claims analysis using the Merative™ MarketScan® databases between 2016 and 2021. As no diagnosis codes for MACLD exist in claims, we defined 2 cohorts of patients receiving treatment for possible rMACLD as follows: 1) patients who initiated ≥28 days of continuous treatment with ALIS; and 2) patients who initiated ≥28 days of continuous treatment with ≥1 non-ALIS antibiotic used to treat rMACLD (i.e., parenteral aminoglycoside, clofazimine, fluoroquinolones, linezolid, tedizolid, or bedaquiline) ≥6 months after initiating treatment used for MACLD (i.e., with a combination of ≥2 antibiotics from a macrolide, ethambutol, and a rifamycin). The date of initiating treatment with ALIS or non-ALIS antibiotic for rMACLD was referred to as the index date. Other inclusion criteria: ≥1 diagnosis code for NTMLD anytime pre-index, ≥6 months continuous eligibility pre-index, and ≥12 months continuous eligibility post-index. Hospitalizations (all-cause, respiratory-related, NTMLD-related) and emergency room (ER) visits at 0-6 and 7-12 month post-index periods were compared with baseline (6 month pre-index period) per treatment arm. Results A total of 116 patients comprised the ALIS cohort and 63 patients the non-ALIS cohort. In the ALIS cohort, statistically significant reductions from baseline in all-cause, respiratory-related, and NTMLD-related hospitalizations were observed during the 7-12 month post-index period (Table). In contrast, the non-ALIS cohort did not show significant reductions from baseline in hospitalizations at follow-up. No statistically significant changes from baseline in ER visits were observed in either group. Conclusions Patients treated with ALIS for rMACLD had statistically significant reductions in hospitalizations from baseline during the 7-12 month post-index period, whereas no statistically significant improvements in hospitalizations were observed in the non-ALIS antibiotics group.

Abstract Tumor cells develop various strategies to evade immune surveillance, one of which involves altering the metabolic state of the tumor microenvironment. In response to metabolic stress in the tumor microenvironment, several tumor-infiltrating immune subsets upregulate CD36 to take up lipids. This leads to impaired antitumor immunity, as intratumoral regulatory T cells exhibit increased survival and suppressive activity, whereas CD8+ T cells become more susceptible to ferroptosis and exhaustion. In this study, we develop a humanized anti-CD36 IgG4 antibody, PLT012, against the lipid-binding domain of CD36 with excellent safety and favorable pharmacokinetic features in mice and cynomolgus monkeys. PLT012 alone or in combination with PD-L1 blockade or standard-of-care immunotherapy results in robust antitumor immunity in both immunotherapy-sensitive and -resistant hepatocellular carcinomas (HCC). Notably, PLT012 also reprograms the immune landscape of human HCC ex vivo. Our findings provide proof-of-concept evidence that PLT012 reprograms antitumor immunity in HCC, positioning it as a first-in-class immunotherapy targeting CD36. Significance: Despite the success of cancer immunotherapies, like immune checkpoint inhibitors, many patients still fail to demonstrate significant responses because of metabolic constraints in tumors. PLT012 rejuvenates antitumor immunity by targeting metabolic pathways to reprogram the immune landscape of liver cancer and liver metastasis, with potential to influence future HCC immunotherapy.