Theranostics

Current treatment of IDH-wildtype glioblastoma (GBM) relies on the first-line chemotherapy-temozolomide. Although MGMT methylation is routinely conducted to predict chemosensitivity, its efficacy is often compromised. Thus, there is an urgent need to discover more accurate prognostic biomarkers. Cholesteryl ester (CE) has been recently recognized as a key feature of GBM, however, its role in GBM prognosis remains poorly understood. We first employed label-free stimulated Raman scattering (SRS) imaging to quantitatively analyze CE level in intact tumor tissues obtained from IDH-wildtype GBM patients. Our result revealed significantly prolonged 2-year overall survival (OS) in patients with CE level [&ge;] 40% compared to those with CE level < 40%. CE outperformed MGMT methylation for 2-year OS prognosis (AUC: 0.836 vs. 0.763). Importantly, CE also achieved superior prognostic performance over MGMT methylation on an independent cohort, with higher sensitivity (0.856 vs. 0.667), specificity (0.833 vs. 0.583), NPV (1.00 vs. 0.667), PPV (0.833 vs. 0.583). Given synergistic effects between CE and MGMT methylation, we developed a prognostic model combining these two biomarkers. Specially, machine learning (XGBoost) model exhibited optimal performance in the training cohort (AUC: 0.920), and maintained its superior performance on the independent cohort (sensitivity: 0.946, specificity: 0.873, NPV: 1.00; PPV: 0.917). Mechanistically, integrative analysis of TCGA database linked poor prognosis to the coordinated upregulation of genes involved in cholesterol efflux, hydrolysis, transport, and inhibition of de novo synthesis, unraveling a possible underlying mechanism between poor prognosis and cholesterol metabolism. This work identified CE as a prognostic biomarker for IDH-wildtype GBM.

Breast cancer is the most common malignancy in women, with triple-negative breast cancer (TNBC) representing the most aggressive subtype and carrying a poor metastatic prognosis. Metastasis requires tumor cells to cross the endothelial barrier, a process facilitated by tumor-derived extracellular vesicles (EVs), which can disrupt vascular integrity. Fluid shear stress (FSS), generated by blood flow, shapes endothelial physiology and may influence EV uptake, yet the mechanisms underlying TNBC-derived small EV (sEV) internalization remain unclear. Here, we investigated TNBC sEV-endothelial interactions using combined in silico and in vitro approaches. Human umbilical vein endothelial cells (HUVECs) were cultured under static or FSS conditions (20 dyn/cm{superscript 2}), followed by proteomic profiling and protein-protein interaction analyses with sEV proteomes. Uptake assays employed pharmacological inhibition (Dynasore, M{beta}CD, Pitstop2), Caveolin-1 (CAV-1) and Clathrin Heavy Chain (CLHC), siRNA-mediated knockdown, and junctional interaction analyses via confocal microscopy and co-immunoprecipitation. FSS downregulated proliferation- and angiogenesis-associated proteins while upregulating adhesion and cytoskeletal regulators assessed by proteomics. Network analysis identified clathrin- and caveolin-mediated endocytosis (CME and CavME), integrins, and early endosomes as central mediators of sEV uptake. Functionally, uptake was reduced by Pitstop2, M{beta}CD, and CAV-1/CLHC knockdown under static conditions, but silencing paradoxically enhanced uptake under FSS, suggesting compensatory flow-dependent pathways. Notably, under FSS, sEVs accumulated at endothelial junctions, colocalizing with VE-CAD and associating with CLDN5, indicating a potential disruption mechanism of adherens and tight junctions and consequent endothelial permeability. These findings identify CME and CavME as key uptake routes while underscoring FSS as a critical determinant of endothelial-tumor EV interactions. By revealing junctional targeting of sEVs, this work provides new mechanistic insight into vascular remodeling during metastasis and highlights EV pathways as potential therapeutic targets in TNBC. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=104 SRC="FIGDIR/small/721946v1_ufig1.gif" ALT="Figure 1"> View larger version (25K): org.highwire.dtl.DTLVardef@f91c5org.highwire.dtl.DTLVardef@2b4dc8org.highwire.dtl.DTLVardef@ff94f1org.highwire.dtl.DTLVardef@18b714b_HPS_FORMAT_FIGEXP M_FIG C_FIG Uptake and localization of sEVs on HUVEC under (a) static and (b) fluid shear-stress conditions. sEVs: Small Extracellular Vesicles. CME: Clathrin-mediated Endocytosis. CavME: Caveolin-mediated Endocytosis. CLDN5: Claudin-5. VE-CAD: Vascular Endothelial Cadherin. FSS: Fluid shear-stress.

Immune checkpoint inhibitors (ICI) have revolutionized cancer therapy, yet response rates remain suboptimal across many solid tumors, and resistance mechanisms, particularly those involving glycans, are not fully understood. Recent studies have identified sialic acid-containing glycans and their interactions with Siglec receptors on tumor-associated macrophages as an important contributor to immune suppression within the tumor microenvironment (TME). Targeting this sialic acid-Siglec axis by glycan engineering with sialidases and other glycosidases has shown therapeutic potential in preclinical models. However, safe and effective delivery of sialidases to tumors remains a challenge. Here, we present a novel approach using adeno-associated virus (AAV)-mediated therapy to deliver sialidases (AAVSia) and other glycosidases, including fucosidase, directly to the TME. Intratumoral administration of AAVSia in mouse models resulted in significant tumor growth reduction, enhanced survival, and robust systemic antitumor immunity through improved cross-presentation and dendritic cell activation. Furthermore, combining local sialidase expression with fucosidase treatment and classical PD-1 blockade allowed a synergistic effect, amplifying antitumor response. Our findings highlight the therapeutic promise of glycoengineering the TME using local delivery systems and support the development of combination strategies to overcome glycan-mediated resistance in cancer immunotherapy. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=129 SRC="FIGDIR/small/720097v1_ufig1.gif" ALT="Figure 1"> View larger version (34K): org.highwire.dtl.DTLVardef@dc9d72org.highwire.dtl.DTLVardef@1e4e455org.highwire.dtl.DTLVardef@4a8f93org.highwire.dtl.DTLVardef@11813a3_HPS_FORMAT_FIGEXP M_FIG C_FIG

Radiotherapy is widely used in the management of brain tumors; however, it is often associated with delayed adverse effects, including cognitive decline and depression-like behavior. These effects are thought to arise, in part, from suppressed hippocampal neurogenesis, altered neuronal architecture, and microglial dysfunction. Despite this, the precise mechanisms underlying irradiation-induced cognitive deficits, as well as effective therapeutic interventions, remain poorly understood. In the present study, six-month-old male mice were subjected to a single 9 Gy dose of cranial irradiation, followed by behavioral assessments several weeks post-exposure. We observed that cranial irradiation significantly impaired hippocampal-, prefrontal cortex-, and cortical-dependent memory functions. Notably, treatment with dehydrozingerone (DH), a curcumin analog (50 mg/kg, oral administration for two weeks), markedly prevented these cognitive deficits. At the molecular level, irradiation disrupted the activity of key enzymes involved in the tricarboxylic acid (TCA) cycle and the glutamate-glutamine/GABA cycle, both of which were restored following DH treatment. Furthermore, irradiation induced dysregulation of genes and proteins associated with glycolysis (Atp2b1, mt-Nd2, mt-Atp6), mitochondrial energetics (mt-Atp8, mt-Cytb), glucose transport (Slc4a5), insulin resistance (Etnppl), lipid metabolism (Pla2g3, Plin4), and inflammation (Ighg2c), all of which were significantly normalized by DH. Importantly, DH also prevented irradiation-induced loss of cell-type-specific glucose transporter expression, including GLUT3 in neurons and GLUT5 in microglia. In conclusion, our findings suggest that DH is a promising therapeutic candidate for mitigating irradiation-induced energy deficits and cognitive impairments, likely through modulation of metabolic and mitochondrial pathways.

Colony stimulating factor 1 receptor (CSF1R) is a tyrosine kinase receptor that is expressed exclusively in microglia within the CNS. Its endogenous ligands, colony stimulating factor-1 (CSF1) and interleukin-34 (IL-34), are released from neurons, positioning CSF1R as a key mediator receptor of neuron-glia communication. CSF1R is considered not only a potential drug target, but also a biomarker of neuroinflammation. From that perspective, selective radioligands for neuroimaging are of great interest for imaging neuroinflammation and determining drug occupancy. In this study, we have validated the binding characteristics of a CSF1R inhibitor, 4-((5-MethOxy-6-((5-methoxypyridin-2-yl)methoxy)pyridin-3-yl)methyl)-2-(1-methyl-1H-pyrazol-4-yl)pyrimidine (5-MOP) as a novel CSF1R radioligand, by performing in vitro saturation binding experiments in human and murine tissues. 5-MOP was found to be selective for CSF1R among a broad range of kinases. Autoradiography revealed that [3H]5-MOP binds with high affinity (KD = 9.8 nM) to a single saturable binding site in human meningioma tissues, and this binding was displaced with known CSF1R inhibitors, including CPPC, sCSF1inh and GW-2580. In contrast, CPPC, which has been extensively used as a CSF1R radioligand showed substantial cross-reactivity to other brain kinases, including Trk A/B/C, and [3H]CPPC could only be displaced with CPPC itself, not by other ligands, including 5-MOP. These results identify [3H]5-MOP as the most selective radioligand currently available, enabling accurate detection of drug occupancy and activated microglia. Significance of the studyThis study identifies and validates a novel selective radioligand that binds CSF1R with high selectivity and low nanomolar affinity. Because CSF1R is selectively expressed in activated microglia, this radioligand could be useful for detecting neuroinflammatory activity.

Resistance to targeted therapy in HER2-positive breast cancer remains a clinical challenge, especially for patients with relapsed or metastatic disease. Particularly, persistent activation of hypoxia-inducible factor 1 (HIF-1) signalling is well documented in the context of trastuzumab and trastuzumab emtansine resistance. To achieve a deeper understanding of how HIF-1 activity modulates the response to anti-HER2 treatment, we functionally characterized a cellular model of hypoxia-induced drug resistance for HER2-positive breast cancer using shotgun proteomics. By global phosphoproteomics profiling, the Rac1 pathway was identified as one of the most enriched signalling networks under hypoxia. Furthermore, the selective Rac1 blockade with the 1A-116 small-molecule inhibitor sensitised HER2-positive cells to trastuzumab in both 2D and 3D culture systems. Altogether, our findings demonstrate that hypoxic conditions induce the resistance of HER2-positive breast cancer cells to targeted therapy and suggest the therapeutic potential of Rac1 inhibition to enhance trastuzumab efficacy. HighlightsO_LIHypoxic conditions induce trastuzumab resistance in HER2-positive breast cancer. C_LIO_LIRac1 signalling was mapped under hypoxia by phosphoproteomics profiling. C_LIO_LIRac1 inhibition sensitises HER2-positive cells to trastuzumab. C_LI

Pioneering research is adapting chimeric antigen receptors (CARs) from oncology to Alzheimers disease (AD) by targeting amyloid beta (A{beta}). Newer synthetic receptor systems can go beyond, transforming cells into targeted biological drug factories that can couple A{beta} detection to synthesis and secretion of genetically encoded therapeutics. Among candidate systems, T cells Redirected for Universal Cytokine Killing (TRUCK), synthetic Notch (synNotch), and Synthetic Intramembrane Proteolysis Receptors (SNIPR) have shown promise in oncology. Here, we adapt these platforms to AD using a shared A{beta}-targeting binding domain derived from Aducanumab (Aduhelm), coupled to inducible expression cassettes driving identical transgenes: secreted Metridia luciferase (MetLuc) and a Lecanemab (Leqembi)-based chimeric human-mouse antibody (chLecanemab). To validate these systems in vitro, Jurkat clones expressing each receptor were treated with oligomer-enriched A{beta} (A{beta}O) to model AD, and receptor output was quantified by media MetLuc levels and chLecanemab colocalization with A{beta} aggregates. For TRUCK systems, we show the A{beta}-targeting CAR successfully activated Jurkat cells by flow cytometry. We also show that six Nuclear Factor of Activated T-cells (NFAT) tandem repeat response elements (6xNFAT) paired with either minimal interleukin-2, synthetic TATA box, or minimal cytomegalovirus promoters resulted in functional regulatory regions. Despite this, all TRUCK variants failed to significantly upregulate MetLuc in response to A{beta}O. In contrast, both synNotch and SNIPR responded robustly to A{beta}O, with SNIPR outperforming synNotch in both MetLuc and chLecanemab production. These findings establish SNIPR and synNotch as promising platforms for future research on cell-based targeted therapeutic delivery in AD.

Clot resistance to pharmacological thrombolysis remains a critical challenge in ischemic stroke (IS) management. Thrombus heterogeneity, particularly the presence of thrombolysis-resistant domains composed of dense fibrin and non-fibrin components, including neutrophil extracellular traps (NETs), significantly limits the efficacy of recombinant tissue-type plasminogen activator (r-tPA) and its variant, Tenecteplase (TNK). Consequently, novel therapeutic strategies are urgently required. Emerging evidence suggests that co-administration of deoxyribonuclease I (DNase I) with r-tPA can degrade DNA fibers and enhance clot lysis. In this study, we optimized a previously developed theranostic agent--iron oxide microparticles coated with polydopamine--by dual-grafting both r-tPA and DNase to target resistant thrombi. Using functional ultrasound imaging (fUS) during the acute phase of IS, we demonstrated accelerated reperfusion with this dual-functionalized platform in a r-tPA resistant IS model. Furthermore, MRI analysis confirmed a significant reduction in lesion volume at 24 hours, correlating with improved functional recovery five days post-ischemia.

Multipotent mesenchymal stem cells (MSCs) including bone marrow stromal cells (BMSCs) have shown analgesic efficacy in recent years. Studies suggested that the therapeutic effect of MSCs was mediated by their secreted small extracellular vesicles (sEVs) mainly exosomes. The present study evaluated the antihyperalgesic effect of BMSC-related sEVs in a mouse model of neuropathic pain involving chronic constriction injury of the infraorbital nerve (CCI-ION). Our separation protocol generated EV particles mostly sized in the range of exosomes (30-170 nm) and express exosome marker proteins CD9, CD81, and Tsg101, suggesting their endosome origin. We show that intravenous injection of BMSC-related sEVs attenuated pain hypersensitivity induced by CCI-ION as indicated by decreased mechanical hypersensitivity (von Frey test) and reduced aversion to noxious stimulation (conditioned place avoidance test). The antihyperalgesic effect of sEVs was observed in both female and male animals, and the effect was dose-dependent. sEVs from NAIVE serum-treated BMSC cultures produced short-lasting antihyperalgesia in male but not female mice, suggesting a subtle sex difference. The antihyperalgesia of sEVs from BMSC culture was blocked by the pretreatment of the culture with GM4869, the antagonist of exosome secretion, suggesting that the effect was not related to other co-isolated soluble mediators but mediated by MSC-derived exosomes. Interestingly, the prior injury condition in which sEVs were isolated favors the pain-relieving effect of sEVs. sEVs isolated from the serum of BMSC-treated animals receiving tendon ligation (TL) injury attenuated hyperalgesia for 24 h, while sEVs from the serum of BMSC-treated NAIVE animals only attenuated hyperalgesia at 3 h after injection. sEVs from the BMSC culture treated with the serum of TL rats were antihyperalgesic, but sEVs from the BMSC culture treated with the serum of naive animals were ineffective. Our results indicate that BMSC-related sEVs produced antihyperalgesia similar to that produced by BMSCs. The results suggest that the interactions between BMSCs and injury conditions are crucially important for producing efficacious sEVs/exosomes and support that the effect of sEVs could be optimized by priming BMSCs with injury-related conditions.

Chimeric antigen receptor (CAR) T-cell therapy has shown remarkable efficacy in hematological malignancies, yet its efficacy in solid tumours remains limited by poor persistence and progressive exhaustion within the tumour microenvironment. These barriers may be particularly pronounced in emerging in vivo CAR-T therapies, in which transient transgene expression and insufficient control over T-cell differentiation restrict the generation of durable antitumour immunity. Here, we report a primary lymphoid tissue-targeting lipid nanoparticle (pLNP), that directs in vivo CAR-T programming to the thymus and lymphoid tissues, thereby increasing the proportion of stem-like CAR-T cells and promoting durable, exhaustion-resistant antitumour responses. After antibody conjugation, pLNP enabled in vivo CAR expression in developing T cells, generating CAR-T cells enriched in naive and stem cell-like memory phenotypes with prolonged persistence. To reinforce this, we co-administered interleukin-7 (IL-7) mRNA, which increased stem-like CAR-T populations, favoured progenitor exhausted T (Tpex) cells over terminally exhausted states, and enhanced cytotoxic function without overt inflammatory amplification. This stemness-promoting strategy also improved responsiveness to immune checkpoint blockade, producing synergistic antitumour effects with anti-PD-1 therapy, reducing LNP dose requirements, and inducing durable tumour regression with prolonged survival in both subcutaneous and orthotopic DLL3-positive small-cell lung cancer models. Similar enhancement of in vivo CAR-T efficacy was also observed in aged mice with thymic involution. Together, these findings illustrated that primary lymphoid tissue-directed in vivo CAR-T programming is a potential strategy to overcome insufficient persistence and progressive exhaustion in solid tumours.

Osteosarcoma (OS) is the most prevalent primary bone malignancy in children and adolescents; however, therapeutic outcomes remain suboptimal due to tumor heterogeneity, chemoresistance, and inadequate immune activation. Doxorubicin (Dox), the standard therapy that induces immunogenic cell death, has its efficacy compromised by the immunosuppressive tumor microenvironment (TME). While interleukin-12 (IL-12) can activate and recruit various immune cells, making it an attractive combination partner, its systemic delivery is severely limited by dose-limiting toxicity. We have previously reported that intravenous injection of A3 collagen binding domain (CBD) of von Willebrand Factor preferentially accumulates into the TME of various tumor models enriched in collagen I and III. Furthermore, CBD-fused IL-12 (CBD-IL-12) demonstrated superior therapeutic effects against various cancer models compared to unmodified IL-12 due to its collagen-targeted delivery and the resulting tumor-localized inflammation. Given that the OS TME also exhibits higher collagen I and III expression compared to normal bone, we hypothesized that a CBD-IL-12 fusion protein could showcase potent anti-tumor efficacy in OS via tumor-specific accumulation. Here, we demonstrated that CBD-IL-12 exhibited 4-fold enhanced tumor accumulation compared to unmodified IL-12 and increased cytotoxic T cell infiltration by 2.2-fold within the immune-cold microenvironment in a mouse model of OS. The combination of CBD-IL-12 with Dox significantly prolonged median survival in two independent murine OS models. This coordinated approach utilizing Dox coupled with precision-targeted IL-12 immunotherapy represents a clinically translatable strategy that overcomes the inherent limitations of single-agent treatments for OS. HighlightO_LICollagen-targeted IL-12 increases tumor accumulation in osteosarcoma. C_LIO_LIThe collagen-targeted IL-12 synergizes with doxorubicin in osteosarcoma models. C_LIO_LICombination therapy enhances T cell differentiation and activates innate immunity. C_LI

The anticancer efficacy of radiotherapy (RT) is limited by acquired radioresistance (RR). Here, we aim to characterize prolonged responses of breast carcinoma cells to hypofractionated irradiation (hFI). To this end, murine mammary 4T1 tumor cells (4T1WT) were subjected to a clinically oriented hFI protocol (56 Gy cumulative dose) to select radioresistant cells in vitro (4T1RS). Furthermore, hFI of subcutaneously growing 4T1CTR tumors (hFI; 24 Gy cumulative dose) was performed to radioselected 4T1IR cells in vivo. Following single irradiation in vitro, radioselected 4T1RS cells revealed increased proliferation, attenuated G2/M arrest and reduced apoptosis as compared to parental 4T1WT cells. Moreover, 4T1RS cells showed increased expression of DNA-damage response (DDR)-related proteins (pKAP1, pCHK2, {gamma}H2AX) and improved DSB repair efficiency as demonstrated by nuclear {gamma}H2AX foci analyses. The mRNA expression of factors regulating cell cycle progression, DDR, apoptosis and oxidative stress was substantially different between both cell variants in vitro. Ten days after hFI of in vivo growing tumors, residual DNA damage and apoptosis were increased in the radioselected 4T1IR tumors, whereas proliferation was reduced as compared to non-irradiated 4T1CTR control tumors. Both irradiated and non-irradiated tumors revealed complex differences in the mRNA expression profile of susceptibility- and metastasis related genes, including GADD45a, DUSP1, CDKN1a and NQO1 as well as CD44 and Rho-related factors, respectively. Moreover, hFI stimulated the infiltration of MPO-positive immune cells into tumor tissue while the presence of CD3-positive cells was reduced in the tumor area. In addition, hFI in vivo resulted in a dysregulated mRNA expression of various immune cell markers, Rho-regulatory factors, tissue remodeling molecules and cell adhesion factors. Summarizing, we identified long-lasting adaptive changes following hFI in vitro and in vivo that are associated with DNA replication, DNA repair, senescence and apoptosis as well as immune cell infiltration and tissue remodeling.

Based on the success in pre-clinical models, methods that reduce sialylation in tumors have progressed to clinical trials, as this improves anti-tumor cellular responses. Immune responses against cancer can also be mediated by soluble, non-cellular mechanisms, such as the complement system. Dysregulation of the complement cascade and hypersialylation are hallmarks found across tumor types. Sialic acids are known to interact with complement proteins. However, the downstream pathways involved in the regulation of the complement cascade when reducing sialylation in tumors remain unclear. Here, using human melanoma cell lines and patient samples, we show that metabolic or enzymatic targeting of sialylation directly increases the activation of the complement, enhancing C3 opsonization of tumor cells and the formation of the membrane attack complex. This is mediated by the classical pathway of the complement system, in line with increased binding of immunoglobulins to tumor cells when sialylation is impaired. Our work positions the complement cascade as a relevant anti-tumor response playing a role when sialylation is targeted for cancer treatment. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=99 SRC="FIGDIR/small/723302v1_ufig1.gif" ALT="Figure 1"> View larger version (20K): org.highwire.dtl.DTLVardef@8ef68forg.highwire.dtl.DTLVardef@1dd30d4org.highwire.dtl.DTLVardef@b0c9ecorg.highwire.dtl.DTLVardef@98cc49_HPS_FORMAT_FIGEXP M_FIG C_FIG

Skeletal muscle possesses remarkable regenerative capacity. However, in limb-girdle muscular dystrophy-2F (LGMD2F), this capacity is compromised by persistent innate immune activation, whose transcriptional landscape remains unexplored. In parallel, (-)-Epicatechin has emerged as a promising compound with beneficial effects on muscle and notable anti-inflammatory properties. We therefore used (-)-Epicatechin treatment to test whether it can alleviate LGMD2F-associated transcriptional and immune dysregulation. Here we provide the first transcriptomic characterization of LGMD2F using the Sgcd-/- mouse model, along with the first RNA-sequencing-based evaluation of (-)-Epicatechin treatment. We profiled two functionally distinct muscles -- the soleus and EDL -- through bulk RNA-sequencing coupled with immune cell-deconvolution. Sgcd-/- muscles exhibited marked transcriptional dysregulation, more pronounced in the soleus and associated with enhanced innate immune signaling. (-)-Epicatechin induced a muscle- and genotype-dependent transcriptional response: in wild-type animals, the EDL displayed the highest number of differentially expressed transcripts, whereas in Sgcd-/- mice, the soleus showed the most prominent response. This shift was accompanied by downregulation of Toll-like receptor and RIG-I-like receptor pathways, along with suppression of NF-{kappa}B2 and interferon-stimulated genes. Together, these findings identify innate immune overactivation as a central feature of LGMD2F and reveal (-)-Epicatechin as a context-dependent modulator of muscle-specific transcriptional responses.

Lung is a major site of metastases for many primary cancers associated with poor outcomes. A central challenge in cancer immunotherapy is overcoming tumor immune evasion, which limits effective antitumor responses. Here, we investigated whether combinatorial mRNA-encoded cytokine therapy can overcome tumor immune evasion by coordinately engaging innate and adaptive immunity, using murine models of pulmonary metastases. We employed intravenously administered cationic nucleoside-modified mRNA-lipoplexes (RNA-LPX) for targeted delivery of mRNA-encoded cytokines to the lung. The cytokine mix containing interferon-, half-life extended interleukin (IL)-7, and a half-life extended IL-2 variant with reduced CD25-binding modulated the tumor immune microenvironment resulting in a potent and broad anti-tumor response and prolonged survival with good tolerability at the conditions tested. Using cell depletion experiments, we demonstrated that both T and natural killer (NK) cells are crucial mediators of the observed anti-tumor efficacy of the cytokine RNA mix, which induced activation and effector function of NK and T cells, coupled with reduced regulatory T cells (Treg) numbers and Treg activation in the lung. Importantly, antitumor efficacy was maintained in models of impaired antigen presentation, including loss of an immunodominant tumor antigen and MHC class I deficiency, where NK cells served as the primary effectors. The cytokine RNA mix induced immune cell activation in the primary human lung tumor culture, suggesting potential for translational application. Collectively, these findings demonstrate that combinatorial cytokine therapy can drive both antigen-dependent and antigen-independent tumor control for the treatment of lung metastases.

Atopic dermatitis (AD) is a highly prevalent, relapse-remitting, inflammatory skin disease, the hallmark symptom of which is chronic itch. Mechanisms underlying AD itch are multifactorial, involving various cells, receptors, and mediators. Developing a physiologically relevant, human model system for AD itch research and drug development is crucial. To this end, human induced pluripotent stem cell-derived sensory neurons (iPSCSNs) were cultured with human primary keratinocytes to form deconstructed skin models. Using Ca2+-imaging in a direct contact, 2.5D co-culturing format, which mimics natural skin innervation and permits both paracrine exchange and juxtacrine signaling, iPSCSNs exhibited functional TRPA1 responses not seen in monotypic iPSCSN cultures or in iPSCSNs conditioned with keratinocyte medium. Different AD-associated cytokines were used to stimulate the co-culture systems to mimic an inflamed lesional skin environment, whereby TNF was found to increase iPSCSN chemosensitivity. Finally, both TRPA1 and JAK1/2 inhibition reduced iPSCSN responses to pruritogens (TSLP, IL-31), thus supporting TRPA1 as a therapeutic target for AD itch in humans. This study demonstrates that human deconstructed skin models can be a useful tool in AD and broader pruritus research. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=181 SRC="FIGDIR/small/724000v1_ufig1.gif" ALT="Figure 1"> View larger version (35K): org.highwire.dtl.DTLVardef@11c0c9borg.highwire.dtl.DTLVardef@7fa518org.highwire.dtl.DTLVardef@2fe7a2org.highwire.dtl.DTLVardef@1105fa7_HPS_FORMAT_FIGEXP M_FIG C_FIG

Spinal cord injury (SCI) is a devastating neurological condition with limited regenerative capacity. Stem cell-based approaches have emerged as promising strategies due to their neuroprotective and immunomodulatory properties, largely mediated by small extracellular vesicles (sEVs) and their molecular cargo, including miRNAs. In this study, we aimed to evaluate the neuroprotective and anti-apoptotic potential of sEVs derived from SPC-01 and iMR-90 neural stem cell sources using an in vitro rat model of SCI. sEVs were isolated from conditioned media and characterized by multi-angle dynamic light scattering and Western blot analysis. Organotypic spinal cord slices (SCS) were used as an in vitro SCI model, with injury induced at 18-20 days, followed by immediate sEV application. After 72 h, tissue samples were collected and tissue was analyzed for markers of apoptosis, cytoskeletal integrity, and survival-related signaling pathways. Results show that SCI induced cytoskeletal disruption and increased apoptotic markers. Treatment with sEVs mitigated these changes, reducing injury-associated protein levels toward baseline. Both SPC-01- and iMR-90-derived sEVs exerted comparable neuroprotective effects, accompanied by decreased PTEN expression, enhanced STAT3 phosphorylation, and increased levels of the anti-apoptotic protein Bcl-xL. In parallel, reduced Nogo-A expression and normalization of RhoA suggested improved cytoskeletal stability and attenuation of inhibitory signaling. Together, these findings demonstrate that neural stem cell-derived sEVs promote early neuroprotective responses in vitro by modulating key signaling pathways, reducing apoptosis, and stabilizing cytoskeletal dynamics, supporting their potential as a cell-free therapeutic strategy for SCI.

Lysosomal trafficking and homeostasis are biological functions that are pivotal for DRG neurons, given their metabolic demands and extremely long axons. Previous studies indicate that lysosomal signaling is altered in a mouse model of chemotherapy-induced peripheral neuropathy (CIPN) and that blocking mitogen activated protein kinase-associated kinase (MNK1/2) signaling can alleviate pain behaviors in CIPN. Here, we investigated lysosome dynamics and lysosome-associated signaling in a mouse model of CIPN induced by paclitaxel (PTX), a chemotherapeutic agent used for various types of cancer. Using spinning disk super-resolution microscope (SPINSR), we demonstrate that PTX treatment in vivo causes reduced lysosome motility observed in vitro. PTX likewise drives the accumulation of Sequestosome 1 (SQSTM1), also known as P62, in cultured mouse DRG neurons, indicating lysosomal dysfunction in DRG neurons. The transcription factor EB (TFEB), a master regulator of lysosomal biogenesis, was also upregulated in the nucleus of cultured mouse DRG neurons treated with PTX. In line with this, increased lysosomal-associated membrane protein 1 (LAMP1) expression was observed in PTX-treated mice. Given that our previous work demonstrated PTX treatment increases MNK1/2-eIF4E signaling in DRG neurons, we examined whether MNK1/2 inhibition could rescue lysosomal dysfunction. Treatment with Tomivosertib (eFT508), a potent MNK1/2 inhibitor, restored P62 levels in DRG neurons of PTX-treated mice and reduced TFEB in DRG treated in vitro. To establish translation relevance, we further show that PTX elevates phosphorylated eiF4E (p-eIF4E) in human DRG neurons, and concurrent eFT508 administration attenuates this effect. Collectively, these findings indicated that PTX disrupts lysosome trafficking and biogenesis, and that MNK inhibition with eFT508 restores lysosomal signaling and can serve as a neuroprotective strategy for CIPN.

Background: Immune-oncology has revolutionized cancer treatment, but some patients fail to benefit due to primary resistance and tumour-immune evasion. Extracellular vesicles (EVs) are secreted by both tumour and immune cells and mediate communication between cancer cells and the immune system. Our study used proteomic profiling of circulating EVs collected from NSCLC patients treated with immune checkpoint inhibitors (ICI) to identify predictive biomarkers of response as well as immune evasion mechanisms related to treatment resistance. Methods: EVs were isolated from plasma collected prior to ICI treatment using peptide-affinity purification and high-throughput proteomics was performed using Proximal Extension Assay. Differentially expressed EV proteins between durable (DR) and non-durable responders (NDR) were identified and evaluated using Cox proportional hazards regression, survival analysis, sex-stratified analysis, as well as pathway and network analysis. Results: Proteomics analysis identified 116 differentially expressed EV proteins between DR and NDR. NDR was characterized by enrichment of inflammatory, angiogenic, and immune-suppressive EV proteins, such as IL1RL1, TFRC, IL6ST, galectins, TNF superfamily death receptors, chemokines, and PCSK9. Pathway analysis revealed enrichment of angiogenesis, chemotaxis, ECM remodeling, and neutrophil degranulation associated with poor progression-free survival (PFS). In contrast, DR to ICI treatment was associated with EV proteins related to T- and B-cell activation and adaptive immunity. Sex-related differences in abundance and association with PFS was observed for certain EV proteins, including IL1RL1 and TFRC. A six protein EV model (IL1RL1, TFRC, ERI1, CCN5, IGFBPL1, and TNFRSF13C) demonstrated good prognostic performance for identifying NDR (AUC = 0.907) and stratified patients into three discrete risk groups. Conclusions: High-plex EV proteomics revealed biologically coherent tumour-immune signaling programs that are associated with ICI treatment resistance. Profiling circulating EVs may improve our understanding of EV-mediated immune evasion mechanisms and identify protein signatures that reflect the tumour immune microenvironment and predict response to immune checkpoint blockade.

Leukocyte immunoglobulin-like receptor B4 (LILRB4, ILT3) is an inhibitory immune checkpoint expressed on myeloid cells, where it contributes to immunosuppression within the tumor microenvironment. Secretogranin 2 (SCG2) has recently been identified as a functional ligand of LILRB4, yet small molecule modulators of this interaction remain unexplored. Here, we report the development of a high-throughput time-resolved fluorescence resonance energy transfer (TR-FRET) assay to interrogate the LILRB4 (ILT3)-SCG2 interaction. The assay demonstrated robust performance and was validated using a blocking anti-LILRB4 antibody, consistent with orthogonal ELISA measurements. Pilot screening of chemical libraries identified 23 primary hits, of which two compounds, BMS-813160 and PSB-603, showed reproducible, dose-dependent inhibition with TR-FRET IC50 values of 26.7 {+/-} 1.03 {micro}M and 37.2 {+/-} 2.14 {micro}M, respectively. Activity was confirmed by ELISA, supporting the robustness of the assay. This platform enables high-throughput discovery of first-in-class small molecule modulators of the LILRB4-SCG2 immune checkpoint and provides a foundation for targeting myeloid-driven immunosuppression.