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Frontiers in Oncology

Frontiers Media SA

Preprints posted in the last 30 days, ranked by how well they match Frontiers in Oncology's content profile, based on 95 papers previously published here. The average preprint has a 0.14% match score for this journal, so anything above that is already an above-average fit.

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Occurrence of Biased mTOR Signaling in Hepatocellular Carcinoma

Singh, R.; Patel, N.; Singh, N.; Mourya, P.; Shingade, A.; Mange, A.; Kaur, J.; Beloshe, S.; Dudhalkar, A.; Chavan, P.; Yengkhom, G. D.; Patkar, S.; Goel, M.; Ingle, A.; Tripathy, S. R.; Epari, S.; Arandkar, S.; Thorat, R.; Shetty, S.

2026-05-26 cancer biology 10.64898/2026.05.22.727188 medRxiv
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BackgroundmTOR signaling promotes cell growth and anabolic processes in all eukaryotes. Hyperactivation of mTOR signaling is associated with various cancers along with hepatocellular carcinoma (HCC). HCC is a highly lethal malignancy with multiple aetiologies such as viral infection, alcohol abuse, and metabolic dysfunction. Therapeutic options for HCC remain limited due to an incomplete understanding of oncogenic drivers and poorly characterized mechanisms of disease progression. MethodsVarious regimens of DEN and CCl4 carcinogen dosage were investigated on C57BL/6J mice to induce HCC. The histological analysis for fibrosis and serum markers for liver function were performed. Molecular analyses of oncogenic drivers were performed in the HCC tissues obtained from mice and HCC patients. The impact of inhibition of mTOR signaling was assessed on HCC progression. ResultsWe established a rapid DEN+CCl4 induced (DCI) HCC model in C57BL/6 mice to study disease progression longitudinally. The molecular analysis revealed upregulation of MAPK and downregulation of mTORC1-S6K-S6 signaling in HCC. However, other branches of mTOR such as mTORC1-ULK1, mTORC1-4EBP1, and mTORC2-PKC were upregulated due to the increased expression. Similar observations were found in tissues derived from HCC patients. Furthermore, inhibition of mTORC1 alone by Rapamycin did not reduce HCC progression but Torin 1 mediated inhibition of both mTORC1 and mTORC2 significantly reduced HCC progression. ConclusionsWe propose this biased mTOR signaling modulates mTOR activity towards specific downstream processes that are crucial for cancer cell growth and targeting both the mTOR complexes has better therapeutic potential in HCC. Impact and ImplicationsThis study provides a rapid pre-clinical model for understanding HCC progression and to explore various intervention strategies. The study reports a novel phenomenon of biased mTOR signaling where deregulation of downstream substrate levels modulates the mTOR activity towards the specific branches, the master regulator of cell growth and metabolism. Furthermore, the study suggests that the clinical investigations exploring the rapalogs against HCC should be cautiously considered depending on the aetiology and signaling status of HCC. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=125 SRC="FIGDIR/small/727188v1_ufig1.gif" ALT="Figure 1"> View larger version (20K): org.highwire.dtl.DTLVardef@58834forg.highwire.dtl.DTLVardef@114f43corg.highwire.dtl.DTLVardef@aea643org.highwire.dtl.DTLVardef@2596ce_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIDEN and CCl4 treatment generated a well-established HCC within 4 months. C_LIO_LILiver fibrosis and serum markers correlated with HCC progression. C_LIO_LIUpregulation of mTOR pathway substrates create biased mTOR signaling. C_LIO_LIDual inhibition of mTORC1 and mTORC2 reduced HCC progression significantly. C_LI

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Unveiling Gloriosine as a Dual-Acting Regulator of Glutamine Metabolism and Ferroptosis in Triple-Negative Breast Cancer: Insights from Network Pharmacology and Experimental Validation

Dey, B.; Chatterjee, E.; Bansode, A.; Goel, B.; Jain, S. K.; Naik, P. K.; Guru, S. K.

2026-05-19 cancer biology 10.64898/2026.05.17.725321 medRxiv
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BackgroundTriple-negative breast cancer (TNBC) is an aggressive subtype lacking well-defined molecular targets, leaving chemotherapy as the primary treatment despite drug resistance, systemic toxicity, and high recurrence rates. Therefore, the development of effective and less toxic therapeutic agents is essential. This study investigated the anti-cancer potential of gloriosine, a bioactive alkaloid with antiproliferative activity and low toxicity toward normal breast cells. MethodsPotential targets of gloriosine were predicted using SwissTargetPrediction, TargetNet, and PharmMapper, and overlapping genes related to TNBC and glutamine metabolism were selected. Protein-protein interaction networks, Gene Ontology, and KEGG pathway enrichment analyses were performed. Molecular docking evaluated binding affinity, followed by in vitro validation using cell viability, colony formation, and wound healing assays. ROS levels were measured by DCFDA and GSH assays, and ferroptosis was assessed by Western blot and FerroOrange staining in MDA{square}MB{square}231 cells. ResultsA total of 100 potential targets were identified, with 60 overlapping with TNBC and glutamine metabolism-related genes. Key targets included SRC, EGFR, mTOR, and HSP90AA1. Enrichment analyses indicated involvement in cancer progression, metabolic regulation, and resistance pathways, including central carbon metabolism, EGFR inhibitor resistance, and ErbB signaling. Gloriosine showed strong binding affinity toward hub targets. Experimental studies confirmed concentration-dependent inhibition of cell proliferation and migration. Mechanistically, gloriosine suppressed glutamine metabolism via GLS1 downregulation and induced ferroptosis, evidenced by increased ROS, glutathione depletion, GPX4 downregulation, and elevated intracellular iron levels. ConclusionsGloriosine exerts significant anti-cancer effects in TNBC through multi-target modulation and induction of ferroptosis, highlighting its potential as a promising therapeutic candidate. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=133 SRC="FIGDIR/small/725321v1_ufig1.gif" ALT="Figure 1"> View larger version (40K): org.highwire.dtl.DTLVardef@ce0ebcorg.highwire.dtl.DTLVardef@29603borg.highwire.dtl.DTLVardef@6d0025org.highwire.dtl.DTLVardef@249700_HPS_FORMAT_FIGEXP M_FIG C_FIG Flow chart of the network pharmacological and in vitro study of gloriosine

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Nationwide Trends and Outcomes in Major Gastrointestinal Cancer Surgery

espinoza, r. e. d. a.; Bastos, L. S. L.; Hamacher, S.; Salluh, J. I. F.; Bozza, F. A.

2026-05-27 oncology 10.64898/2026.05.26.26354087 medRxiv
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Background Complex gastrointestinal (GI) oncologic surgeries carry substantial perioperative risk, and nationwide outcomes in low- and middle-income countries (LMICs) are underreported. This study aimed to evaluate national trends in surgical volume, in-hospital mortality, and intensive care unit (ICU) utilization for major GI cancer surgery in Brazils Unified Health System (SUS) over a 14-year period. Methods A population-based analysis was performed using national administrative databases to identify all adult patients undergoing colectomy, gastrectomy, pancreatic resection or esophagectomy for cancer in the SUS from 2010-2023. Annual rates were age-standardized according to the WHO standard population. Temporal trends were assessed using Poisson regression to estimate average annual percent change (AAPC) with 95% confidence intervals (CIs). Results A total of 179,337 hospital admissions were analyzed (median age 63 years; 48% female). Colectomies accounted for 72% of cases, followed by gastrectomies (19%), pancreatic resections (5%), and esophagectomies (3%). Although crude surgical volume increased, population-adjusted rates declined overall (AAPC -2.09%; 95% CI -2.58 to -1.59), mainly due to reductions in gastrectomies and esophagectomies. Median hospital stay decreased from 9 to 7 days (AAPC -1.93%; 95% CI -2.79 to -1.06). Overall in-hospital mortality declined from 8.1% to 5.7% (AAPC -2.88%; 95% CI -4.15 to -1.59). ICU utilization rose from 37% to 43% of admissions (AAPC +1.31%; 95% CI 0.91 to 1.71). Conclusion Over 14 years, in-hospital mortality and length of stay for major gastrointestinal cancer surgery declined within Brazils universal public health system. These temporal trends occurred alongside expansion of accredited oncology services and increased ICU utilization, although causal relationships cannot be established from administrative data. These findings should be interpreted as hypothesis-generating and highlight the need for more granular hospital-level data in LMIC settings.

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Efficacy and Safety of Povidone Iodine versus Bleomycin for Pleurodesis in Malignant Pleural Effusions: A Systematic Review and Meta-Analysis

Salamullah, S.; Muhammad, M.; Habib, M.; Maulanisa, S. C.

2026-05-13 oncology 10.64898/2026.05.09.26352791 medRxiv
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Malignant pleural effusion (MPE) frequently complicates advanced cancer and impairs quality of life. Chemical pleurodesis with agents such as bleomycin or povidone iodine is widely used, but comparative efficacy and safety remain uncertain. Bleomycin is an established agent but is costly and less available, whereas povidone iodine is affordable and easily accessible. This study aimed to systematically compare the efficacy and safety of bleomycin versus povidone iodine for pleurodesis in patients with malignant pleural effusions. We conducted a systematic review and meta-analysis following PRISMA guidelines. PubMed, Semantic Scholar, and the Google Scholar were searched through May 20th 2025. Studies included randomized controlled trials and cohort studies comparing bleomycin and povidone iodine for pleurodesis in patients with MPE. Seven studies with 392 patients (174 in the povidone iodine group, 218 in the bleomycin group) were included. Success rates for pleurodesis ranged from 71.1% to 100% for povidone iodine and 66.7% to 95.2% for bleomycin. Meta-analysis showed no significant difference in efficacy (RR = 1.04, 95% CI: 0.94-1.15, p = 0.50; I2 = 43%). Both agents were well tolerated, with similar rates of mild adverse events. This study showed no significant bias. Povidone iodine and bleomycin are equally effective and safe for pleurodesis in MPE. Given its lower cost and greater accessibility, povidone iodine may be preferred, especially in resource-limited settings.

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Connecting Baseline Immune Exhaustion in Hot Tumors to Oral Cancer Recurrence and Nodal Metastasis

Shaikh, S.; Basu, S.; Hajihosseini, M.; Nandy, S. K.; Moorthy, M.; Arun, I.; Lali, B. S.; Arun, P.; Mukherjee, G.; Pyne, S.

2026-05-30 oncology 10.64898/2026.05.27.26354295 medRxiv
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Background: The use of immune checkpoint inhibitors (ICIs) in the treatment of cancer has rapidly expanded over the last decade. However, there are several knowledge gaps in understanding how tumor cells evade the immune system. There is paucity of data in HPV negative oral cancer, particularly of the gingivobuccal region. Understanding the mechanism of immune system evasion in this cancer is vital for improving patient outcomes. Methods: We characterized the baseline immune milieu of oral cancer using immunohistochemistry (IHC) on whole tumor sections from 124 cases. Tumors were classified as hot or cold and further stratified into high-risk and low-risk groups. High-risk patients included those with lymph node metastasis at diagnosis/recurrence or distant metastasis within 2 years of treatment completion. Patients without these features were categorized as low risk. Validation by RNA-Seq and Joint Enrichment Analysis of Oncogenic and Immunologic Pathways was carried out in a subset of 46 cases. Results: Hot high-risk tumors (by IHC) were distinguished by elevated PD-L1 expression and reduced NK-cell, PD1, and CTLA-4 expression. There was no difference in the expression levels of CD3+, CD8+, granzyme, or perforin compared to hot low-risk tumors, findings that align with the definition of hot tumors. RNA-Seq revealed a gene signature associated with exhausted T-cells in hot high-risk tumors. Gene and pathway analyses identified differential upregulation of isoform-specific TOX, TCF, CXCR, RUNX, IRF, BRD and BCL6 genes, implicating immune cell exhaustion and tumor aggressiveness. Significantly downregulated genes included PDCD1, HAVCR2, ZAP70, and STAT, indicative of a disabled immune microenvironment. These findings support that a state of immune exhaustion in HHR tumors is driven by progenitor exhausted T-cells and terminally exhausted T-cells; independent of PD1-TIM3. Conclusion: These findings suggest that combining TOX/TCF/BCL6 inhibitors with immune checkpoint inhibitors in the adjuvant setting might benefit patients with hot high-risk tumors. Given the results, testing for a targeted exhaustion-related gene panel at diagnosis is recommended for oral cancers to stratify tumors as high-risk or low-risk. Larger validation studies and clinical trials are now warranted.

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Pharmacological inhibition of deubiquitinase UCH-L1 by LDN57444 sensitises hepatocellular carcinoma to sorafenib by reverting drug-induced adaptive responses

Van De Vijver, E.; Decroix, K.; Burggraeve, D.; Van Wassenhove, P.; De Vos, Z.; Ampe, C.; Devisscher, L.; Van Vlierberghe, H.; Van Troys, M.

2026-05-19 cancer biology 10.64898/2026.05.15.725527 medRxiv
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Background and aimsTherapeutic outcomes for advanced hepatocellular carcinoma remain inadequate, despite recent advances using immunotherapy. Long-term effectiveness of systemic therapies, including second-line multi-tyrosine kinase inhibitor sorafenib, is limited by resistance mechanisms and adverse effects. Upregulated deubiquitinase UCH-L1 is frequently correlated with poor prognosis in cancers. Here, we investigated the therapeutic potential of combining pharmacological UCH-L1-inhibition with sorafenib in HCC. MethodsUCH-L1 expression was analysed in TCGA-LIHC data and patient-derived HCC tissues. Sorafenib and LDN57444 effects were evaluated in vitro in cytotoxicity and invasion assays. Gene and protein expression were examined by RT-qPCR, Western blotting and immunohistochemistry. In vivo efficacy of drug synergy was assessed in an orthotopic xenograft mouse HCC model. ResultsIn silico data-analysis revealed significantly higher UCH-L1 levels in patient HCC tumours versus non-tumour, associated with reduced overall survival. Low-dose sorafenib upregulated UCH-L1 in HCC cell line Hep3B. Paradoxically, this also promoted invasiveness and sustained MEK1/2-ERK1/2-pathway activation. Combining low-dose sorafenib with LDN57444 produced strong synergistic cytotoxicity in vitro, reverted MAPK-activation and suppressed invasion. Consistently, at low sorafenib dose co-treatment with LDN57444 completely inhibited tumour growth of Hep3B xenografts and enhanced sorafenib efficacy. ConclusionLDN57444 sensitises HCC cells to low-dose sorafenib by reverting drug-induced pro-oncogenic signalling and thereby strongly synergises with sorafenib to enhance anti-tumour efficacy in a HCC mouse model. This presents UCH-L1 as a player in treatment-induced adaptive response and supports further exploring UCH-L1-targeting in combination with sorafenib as therapeutic avenue for advanced HCC. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=144 SRC="FIGDIR/small/725527v1_ufig1.gif" ALT="Figure 1"> View larger version (37K): org.highwire.dtl.DTLVardef@176dc91org.highwire.dtl.DTLVardef@8acae8org.highwire.dtl.DTLVardef@f71bborg.highwire.dtl.DTLVardef@1f3c5aa_HPS_FORMAT_FIGEXP M_FIG C_FIG Lay summaryThis study explores a new treatment approach for hepatocellular carcinoma (HCC) by combining two drugs: LDN57444, which blocks the enzyme UCH-L1, and sorafenib, a FDA-approved multi-tyrosine kinase inhibitor. We evaluated the effect of this drug combination in vitro using a HCC cell line and in an mouse HCC-model. The drug combination displayed strong, synergy in lowering HCC cell viability, and greatly reduced invasiveness and in vivo tumour growth. LDN57444 sensitised HCC cells to low doses of sorafenib by preventing UCH-L1-mediated activation of pro-oncogenic signalling. These findings highlight the potential of this new drug combination for treating advanced HCC thereby potentially reducing side-effects and countering drug resistance. Impact and implicationsOur preclinical research introduces a novel combination strategy against advanced HCC that holds potential to improve existing therapies, particularly the second-line multi-tyrosine kinase inhibitor sorafenib. The proposed combination of sorafenib with an inhibitor of the deubiquitinase UCH-L1 not only enhances sorafenib efficacy but present promise to also counter resistance mechanisms. Moreover, because effective responses are achieved at lower drug doses, this may in addition reduce therapy-associated adverse effects further increasing potential impact. While sorafenib is FDA-approved, the UCH-L1 inhibitor LDN57444 needs further (clinical) development to bring our promising findings to full translational potential for HCC patients and physicians.

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Advancing Liver Cancer Precision Medicine with TARGET-SL

Gillman, R.; Dwyer, B. J.; Pasic, S.; Shirolkar, G. D.; Main, N.; The Liver Cancer Collaborative, ; Field, M. A.; Schmitz, U.; Hebbard, L.

2026-05-21 cancer biology 10.64898/2026.05.19.725819 medRxiv
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Background and AimsA major goal of personalised liver oncology is the ability to make targeted predictions about cancer-specific toxicity, however there are limited methods available. To address this, we validated the performance of our bioinformatics framework, TARGET-SL, through ex vivo drug screening. MethodsUsing TARGET-SL we predicted gain of function (GOF), loss of function (LOF) and synthetic lethal (SL) genetic events, and corresponding drug candidates. We validated drug predictions across hepatocellular carcinoma (HCC) cell lines, and a cohort of HCC and cholangiocarcinoma (CCA) patient-derived organoids (PDOs). ResultsFor HCC cells and PDOs we found 37.5% and 25% of the respective selected compounds induced unique target-specific growth inhibition based on genetic biomarkers, suggesting novel biomarker-driven drug sensitivities. ConclusionsOur analyses demonstrate TARGET-SLs potential to enhance personalized drug screening for liver cancer, by focusing on genetically informed targets. This will reduce experimental costs and accelerate the pace of therapeutic discovery. Impact and ImplicationsPrimary liver cancer (PLC) is a cancer with poor prognosis, and current therapies increase survival only for a minority of patients. Through the application of TARGET-SL we can predict, for each patient, the essential genes and corresponding small molecule inhibitors. These data support further investigation in larger patient cohorts and offer the possibility to specify new small molecule inhibitors and to repurpose current drugs for PLC treatment. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=81 SRC="FIGDIR/small/725819v1_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@10cb252org.highwire.dtl.DTLVardef@8f3049org.highwire.dtl.DTLVardef@ab4467org.highwire.dtl.DTLVardef@17f9d3_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LITARGET-SL can predict gene and drug sensitivities for cell lines and patient-derived organoids C_LIO_LIThis may reduce drug screening costs and accelerate the pace of therapeutic discovery. C_LIO_LITARGET-SL may assist in the repurposing of current drugs and their rapid translation for primary liver cancer C_LIO_LITARGET-SL is tumour-type agnostic, and therefore may have application in other cancers with poor prognosis C_LI

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Cancer Prevalence and Patterns in Kilifi County: A 10-year Retrospective Descriptive Study

Masha, M.; Mbugua, R. W.; Abdullahi, M.; Sheikh, N. A.; Omar, A.; Abdihamid, O.

2026-06-01 oncology 10.64898/2026.05.20.26353643 medRxiv
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Abstract Background Cancer is an increasing public health challenge in Kenya, particularly in rural and underserved regions where surveillance systems and diagnostic capacity remain limited. Kilifi County, located along the Kenyan coast, lacks a population-based cancer registry, and data on the local cancer burden is not available. This study aimed to characterize the demographic distribution of patients, cancer burden in the county, and management of cancer cases diagnosed at Kilifi County Referral Hospital (KCRH) over ten years. Methods This retrospective study analyzed the patterns of cancer in Kilifi County using patient records from KCRH during the study period (January 1, 2014, to January 1, 2024). Results A total of 101 patients with cancer were identified, 58% female, with a mean age of 54 years. Most patients were from Kilifi North (47%), with a high proportion reporting no formal occupation (41%) or farming (26%). Esophageal and cervical cancers were the most common (18% each), followed by breast and prostate cancers (5% each), with other malignancies occurring infrequently. Histopathology was the primary diagnostic modality (88%). Staging data were incomplete in 70% of cases; among documented cases, the majority presented with advanced disease (21% stage IV). Due to limited local treatment capacity, approximately half of the patients were referred to tertiary centers for chemotherapy, radiotherapy, or surgery. At data cut-off, 43% had died, 25% were on treatment, and 29% were lost to follow-up, with only 2% completing treatment or under follow-up. Conclusions This study demonstrates a substantial cancer burden in Kilifi County and highlights critical gaps in diagnostic capacity, staging, and continuity of care. Strengthening cancer surveillance systems, expanding diagnostic and treatment infrastructure, and establishing a population-based cancer registry are essential to improving cancer outcomes and advancing equitable care in rural Kenya

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PCSK9 Exhibits Novel Nuclear Localization in LSEC and Its Targeting with Bioinspired Nanoparticles Reduces Colorectal Liver Metastasis

Martin, A.; Duarte Garcia Escudero, M.; Garcia Garcia, H.; Banares, I.; Fontal, N.; Eguia, J.; Garcia Gallastegui, P.; Benito, A.; Saez, F.; Crende, O.; Sanchez Barreiro, A.; Marquez, J.; Khatib, A.-M.; Badiola, I.

2026-05-29 cancer biology 10.64898/2026.05.26.727886 medRxiv
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Background & AimsColorectal cancer liver metastasis is the leading cause of mortality in affected patients, with liver sinusoidal endothelial cells playing a pivotal role in metastatic niche formation. Proprotein convertase subtilisin/kexin type 9 has emerged as a regulator of tumor biology, but its function in the hepatic microenvironment remains poorly defined. This study aimed to characterize the role and subcellular localization of PCSK9 in liver sinusoidal endothelial cells and to evaluate the therapeutic potential of its endothelial-specific inhibition in colorectal liver metastasis. MethodsIn vitro studies were performed using human and murine liver sinusoidal endothelial cells stimulated with conditioned media from metastatic colorectal cancer cells and cancer stem cells. Subcellular localization was assessed by immunofluorescence, immunogold electron microscopy, and biochemical fractionation. Protein interactions were investigated using co-immunoprecipitation and proteomic analyses. For in vivo validation, a murine model of colorectal liver metastasis was generated by intrasplenic injection of tumor cells, followed by systemic administration of chondroitin sulfate-targeted nanoparticles delivering PCSK9 siRNA every 5 days for 18 days. ResultsPCSK9 was consistently expressed in liver sinusoidal endothelial cells and displayed a predominant nuclear localization, which increased upon tumor-induced activation. Proteomic integration identified multiple candidate interacting proteins involved in metabolic and tumor-related pathways. Targeted nanoparticle-mediated delivery achieved efficient PCSK9 silencing in vitro. In vivo, endothelial-specific PCSK9 inhibition significantly reduced liver metastatic tumor burden compared with control groups, whereas free siRNA showed no significant effect. ConclusionsPCSK9 exhibits a novel nuclear localization in liver sinusoidal endothelial cells and potentially interacts with proteins implicated in tumor mediated pathways. Selective inhibition of endothelial PCSK9 using targeted nanoparticles significantly reduces colorectal liver metastasis, highlighting a novel therapeutic strategy focused on the hepatic microenvironment. Impact and ImplicationsThis study provides mechanistic insight into how PCSK9 contributes to colorectal liver metastasis by identifying its novel nuclear localization and potential function in liver sinusoidal endothelial cells. These findings are important for researchers and clinicians seeking to understand microenvironment-driven metastasis and resistance to current therapies. The demonstration that endothelial-specific targeting of PCSK9 reduces metastatic burden suggests a new avenue for therapeutic development beyond systemic inhibition. Such strategies could be translated into precision nanomedicine approaches to improve outcomes in patients with metastatic colorectal cancer while minimizing off-target effects.

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Circulating immune signatures reveal targetable inflammatory pathways in anaplastic thyroid carcinoma

van Houten, P.; Schluter, T.; Sumpter, N.; Changoer, P.; van Emst, L.; Helder, L.; van Heck, J.; Martens, J.; Walraven, J.; Ottevanger, P.; Bonenkamp, H.; de Wilt, J.; Netea, M.; Jaeger, M.; Netea-Maier, R.

2026-05-21 cancer biology 10.64898/2026.05.19.726015 medRxiv
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Anaplastic thyroid carcinoma (ATC) is one of the most lethal malignancies. Immune dysregulation is believed to play an important role in ATC. Here, we aimed to characterize the systemic inflammation and the function of circulating immune cells of patients with ATC. First, we retrospectively assessed biochemical parameters of patients with ATC and observed that high systemic inflammation correlated with worse survival. Next, we prospectively investigated the inflammatory proteome, single-cell peripheral blood mononuclear cell transcriptome and epigenetic changes. Circulating concentrations of proinflammatory cytokines were increased in ATC patients. This proinflammatory profile was apparent at the level of gene transcription and chromatin accessibility, especially in monocytes. These findings were substantiated by an increased capacity of peripheral blood mononuclear cells of ATC patients to produce IL-6, IL-8 and lactate. As IL-6 is known to promote tumor cell survival, we assessed its capacity to influence ATC cell proliferation. Blocking IL-6/gp130/Jak/STAT3 pathway inhibited proliferation of ATC cell lines in vitro. In conclusion, these findings show that ATC is characterized by inappropriate systemic inflammation and epigenetic and transcriptional reprogramming of circulating monocytes. Proinflammatory cytokines released by monocytes support survival and proliferation of ATC tumor cells, suggesting a therapeutic potential of targeting this pathway in ATC patients.

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Brief Report-Combination Capmatinib and Trametinib in Metastatic MET-driven Non-Small Cell Lung Cancer

Brown, T. S.; Lara, M. S.; Jiang, F.; Garon, E. B.; Goldman, J. W.; Riess, J. W.; Blakely, C. M.

2026-05-21 oncology 10.64898/2026.05.19.26353265 medRxiv
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Abstract Introduction: MET tyrosine kinase (TKI) therapy has improved outcomes in patients with non-small cell lung cancer (NSCLC) harboring MET alterations. However, primary and acquired resistance ultimately limits durability of response. This study evaluated the safety and efficacy of the MET inhibitor capmatinib with the MEK inhibitor trametinib in patients with metastatic MET-driven NSCLC who had progressed on prior treatment with at least one MET inhibitor. Methods: A multicenter phase I study evaluated capmatinib in combination with trametinib in patients with advanced stage NSCLC harboring activating MET alterations and prior exposure to at least one MET TKI. A 3+3 dose-escalation design was employed to assess safety and tolerability of the combination. Results: Three patients (n = 3) were enrolled in the study and completed a median of 3 cycles of therapy. Dose-limiting toxicities, including rash, edema, and nausea, necessitated dose reductions in the first two patients and initiation of the third patient at a lower dose level. Ultimately, all patients discontinued therapy due to treatment-related adverse events. The study was terminated early due to poor accrual and TRAEs. No radiographic objective responses were observed. Conclusions: In this phase I trial, capmatinib plus trametinib was associated with significant treatment-related adverse events and treatment was discontinued in all participants. Based on these findings, further investigation of this combination of MET and MEK inhibitors is not recommended.

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Prevention of mRNA vaccine-induced anaphylaxis by peripheral cyclooxygenase inhibitors in an anti-PEG hyperimmune pig model: clinical relevance for nanomedicine-induced infusion reactions

Barta, B. A.; Radovits, T.; Dobos, A. B.; Spiesshofer, S.; Toth, A. G.; Kornev, G.; Gabizon, A.; Merkely, B.; Szebeni, J.

2026-05-29 immunology 10.64898/2026.05.27.727997 medRxiv
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Anti-polyethylene glycol (PEG) hyperimmune pigs, immunized against PEG, provide a sensitive experimental model for the rare anaphylactic reactions induced by mRNA-PEGylated lipid nanoparticle (LNP)-based COVID-19 vaccines, such as Comirnaty. These pseudo-allergic infusion reactions can usually be prevented or attenuated by multicomponent anti-inflammatory premedication regimens; however, no established protocol exists for mRNA-LNP-based COVID-19 vaccines. The aim of the present study was to identify an effective premedication strategy capable of preventing or attenuating these reactions in hypersensitive subjects, using the hyperimmune porcine model. We compared the protective effects of individual pretreatment components; dexamethasone, famotidine, levocetirizine, acetaminophen, diclofenac, indomethacin, by analyzing hemodynamic endpoints (systemic and pulmonary arterial pressure, pulse pressure). All tested compounds modulated Comirnaty-induced anaphylactic responses; however, only cyclooxygenase (COX) inhibitors provided complete protection against anaphylaxis and other abnormal processes. This finding is consistent with the low incidence of infusion reactions to cancer nanomedicines at the Shaare Zedek Oncology Center in Israel which uses COX-inhibitors as premedication. Given that most currently used human infusion-reaction prevention protocols do not include COX inhibitors, and that steroid-containing regimens may potentially counteract vaccine efficacy, our results suggest that COX inhibitors may offer a clinically effective standalone option or form the basis of simplified premedication regimens for preventing this life-threatening condition.

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Cancer Medicine Prices, Availability, and Affordability in Kisumu County, Kenya

OKETCH, J. O.; Amolo, S. A.; Onguru, D. O.

2026-05-28 oncology 10.64898/2026.05.27.26354206 medRxiv
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Background: The rising prices of cancer medicines have intensified concerns about treatment access and health system sustainability particularly in low- and middle-income settings. Systematic facility level evidence on what medicines is actually available, at what prices, and at what cost to patients remains scarce, constraining evidence-based policy reform. Methods: Using adapted WHO/Health action international methodology, we conducted a cross-sectional survey of 52 cancer medicines across five therapeutic classes at five health facilities in Kisumu County, Kenya. Availability was measured as the proportion of facilities stocking each medicine. Affordability was assessed using days' wages required for the lowest-paid government worker to purchase standard treatment regimens, calculated per one chemotherapy cycle and maximum possible cycles. Results: Overall medicine availability was 48.1%, with marked inter-facility variation. Affordability analysis revealed severe financial barriers. The breast cancer AC regimen required 19.6-47.4 days' wages per full course; cervical cancer cisplatin, 19.8-49.2 days' wages; colorectal FOLFOX, 80.0-303.6 days' wages; and prostate docetaxel reached 437 days' wages at the highest-cost facility. The Social Health Authority's (SHA) KES 550,000 annual ceiling adequately covered cytotoxic regimens for common cancers at competitive prices but was exceeded by 24-116% for HER2-positive breast cancer requiring trastuzumab, with further strain for recurrent cervical and metastatic prostate cancers. Conclusions: Cancer medicines in Kisumu County are inconsistently available and highly variable in price resulting in inequitable access. We call for urgent retail price markup regulation, expanded pooled procurement through KEMSA, inclusion of priority targeted therapies on the Kenya Essential Medicines List, and SHA benefit packages redesigned around full-course regimen costs.

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Intratumoral B7H3:CD3 Bispecific T-cell Engager Drives Localized T-cell Accumulation in Canine Sarcoma Patients

Suita, Y.; Ang, L. S.; Brasel, K.; Morris, S. M.; Girard, E. J.; Williams, A. M.; Chen, S. C.; Blumenthal, I.; Hottmann, N. M.; Heusser, J.; Mhyre, D. J.; DeForest, C. A.; Moore, P. F.; Price, J. P.; Fidel, J.; Olson, J. M.

2026-05-31 immunology 10.64898/2026.05.27.728355 medRxiv
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BackgroundBispecific T-cell Engagers (TCEs) targeting B7H3 (CD276) show promise for solid tumors but are limited by systemic toxicities and poor tumor penetration. Intratumoral (IT) delivery is proposed as a solution, but the safety and spatial pharmacodynamics (PD) remain poorly defined in these malignancies. Spontaneous canine tumors serve as a highly translatable model for human therapeutic development due to its clinical, genetic, and immunological similarities to human patients. This study evaluates the feasibility of an IT-delivered B7H3:CD3 TCE in a trial that enrolls companion dogs with solid tumors. MethodsWe engineered a canine B7H3:CD3 TCE and validated its ability to induce T-cell activation and T-cell mediated cytotoxicity in vitro on several B7H3-expressing canine tumor cell lines. Two STS canine patients received intratumoral columnar injections of the TCE and saline (internal control) at fixed distance of 1.5cm using a custom-engineered multi-needle assembly. Safety was evaluated by physical examinations and hematological and biochemical changes in peripheral blood. PD response was analyzed by H&E and immunohistochemistry. ResultsIn vitro assays validated the cytotoxicity of the B7H3:CD3 TCE on B7H3+ canine tumor cell lines. TCE IT administration (7.83 g / 148.2 pmol) was well tolerated with no adverse events greater than Grade 1 and no evidence of systemic cytokine release or organ toxicity. Immunohistochemistry of tumors collected 7 days after TCE administration revealed a significant five-fold increase in CD3+ T-cell density at the TCE injection site (within 0.5 cm radius) compared to internal saline controls. ConclusionsThis study demonstrated the feasibility of evaluating pharmacodynamic response to IT delivery of B7H3:CD3 TCE, namely local T-cell accumulation. T-cell localization around the TCE injection site supports our hypothesis that effective IT immunotherapy might require enhanced volumetric coverage using multi-needle injections and/or co-stimulatory strategies to convert T-cell localization into a robust, sustained anti-tumor response.

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Febuxostat enhances the anti-tumor efficacy of 2-fluoroadenine and 5-methylthioadenosine in MTAP-deleted cancer

Tang, B.; Lee, H.-O.; Krzikike, D.; Gupta, S.; Cai, K. Q.; kruger, w. D.

2026-05-21 cancer biology 10.64898/2026.05.19.726298 medRxiv
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BackgroundHomozygous deletion of the methylthioadenosine phosphorylase (MTAP) gene is a frequent genetic alteration in cancer. MTAP, which creates adenine from 5-methylthioadenosine (MTA), is constitutively expressed in all tissues throughout the body. Previously, we described a novel strategy to specifically target MTAP-deleted cancer cells by combining the antipurine prodrug 2-fluoroadenine (2FA) with MTA. In vitro, this combination efficiently killed MTAP- cancer cells, but in vivo the combination was much less effective in vivo. Here, we explored the role of xanthine oxidase (XO) in this process. Materials and MethodsVarious combinations of 2FA, MTA, and the xanthine oxidase inhibitor febuxostat (FX) were tested in various cancer cell lines grown in vitro and in mice. LC-MS/MS was used to examine the levels and ratio of intracellular 2-FA-containing nucleotides compared to adenine-containing nucleotides. Results and conclusionsThe treatment of cells with 2FA+MTA in vitro resulted in much higher 2FANP/ANP ratios than the same treatment in vivo. The addition of XO to culture media in vitro effectively abolished the killing by 2FA, and this effect was fully reversed by the addition of febuxostat (FX), a xanthine oxidase inhibitor. In vivo, the addition of FX to 2FA results in increased cell killing and toxicity and a 1000% increase in the amount of 2FA converted to 2-FA-monophosphate (2FAMP). Xenograft studies using MTAP- HT1080 and MiaPaCa-2 cell lines have shown that a 2FA/MTA/FX cocktail can cause tumor regression in vivo. These studies suggest that the combination of 2FA/MTA/FX should be explored as a treatment for MTAP- cancer.

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Pre-treatment biopsychosocial predictors of chemotherapy-induced peripheral neuropathy trajectories in people with breast cancer

Auger, C.-A.; Frasie, A.; Bouffard, M.; Therrien, F.; Beland, S.; Dionne, A.; Dworkin, R. H.; Gagliese, L.; Gewandter, J. S.; Jackson, P. L.; Lauzier, S.; Lemieux, J.; Savard, J.; Gauthier, L. R.

2026-05-17 oncology 10.64898/2026.05.13.26353023 medRxiv
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Purpose: Chemotherapy-induced peripheral neuropathy (CIPN) affects many people receiving taxane treatment for breast cancer. Symptom trajectories vary, with some recovering, and others experiencing persistent, or delayed worsening (coasting) symptoms. The prevalence and predictors of these trajectories remain unclear. This study identified the prevalence and biopsychosocial predictors of CIPN persistence, improvement, and coasting within three months post-treatment. Methods: This secondary analysis included participants treated with taxanes for stage I-III breast cancer who completed the Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity-4 (FACT/GOG-NTX-4) at baseline, post-chemotherapy, and three months later. A minimally important difference (MID) from baseline on the FACT/GOG-NTX-4 defined persistence, improvement, coasting, and no MID-CIPN (below the MID threshold at each assessment) trajectories. Baseline assessments included self-reported pain/well-being, sensory, balance, and lower limb physical functioning measures, and sociodemographic and treatment data were collected. Results: Among 102 participants (51.57{+/-}11.24 years), persistence occurred in 34.3%, improvement in 25.5%, coasting in 6.9%, and no MID-CIPN in 33.3%. Compared to no MID-CIPN, older age (OR=1.120; 95%CI: 1.026-1.222), higher expected pain (OR=1.630; 95%CI: 1.082-2.456), and cold hyperalgesia at the foot (OR=1.130; 95%CI: 1.018-1.254) predicted persistence. Lower fatigue predicted improvement (OR=0.904; 95%CI: 0.845-0.968). No predictors were identified for coasting. Conclusion: CIPN trajectories are heterogeneous. Age and pre-treatment pain expectations, cold hyperalgesia, and fatigue differentiate patients with persistent CIPN and those likely to improve from those with no CIPN. Implications for Cancer Survivors: Early identification of individuals at risk for persistent neurotoxicity may support risk stratification and guide targeted supportive care strategies.

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Inhibition of the Adenosine pathway activates the immune response against Mesothelioma.

Costa, C.; Gray, S.; Pinton, G.; Moro, L.; Del Grosso, E.; Bellan, C.; Addi, L.; Lombardi, R.; Bruzzese, f.; De Biase, D.; Pucci, B.; Di Gennaro, E.; Ascierto, P. A.; Gravina, G. L.; Mutti, L.

2026-05-13 cancer biology 10.64898/2026.05.08.722957 medRxiv
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BackgroundMesothelioma (Me) is an aggressive cancer with limited response to conventional therapies. The tumors harsh microenvironment contributes to immune escape and therapy resistance and the effects of ICIs on Me are still unclear. Adenosine, an immunosuppressive molecule produced from AMP by the enzyme CD73, accumulates in hypoxic tumor areas. Elevated CD73 and adenosine receptor A2B (A2Br) levels on Me cells are linked to worse patient outcomes, indicating their important role in disease progression and potential as targets for treatment. AimThis study characterizes the Me-ME (micro environment) and evaluates the efficacy of TT-4 (A2B inibitor) and AB680 (CD73 inibitor), alone or with aPD-1, using 3D models in vitro and in vivo. MethodsCD73 and A2B receptor levels were quantified in tumor and normal samples using qRT-PCR and IHC. Cells lines were treated with CoCl2 to mimic hypoxia, then CD73, A2Br and related markers were analyzed. MSTO-211H and REN cells were silenced for CD73, grown as spheroids and adenosine release was measured. Co-culture spheroids of MSTO-211H and Jurkat cells were treated with AMP and CD73 inhibitor, then analyzed for viability and immune markers. An orthotopic Me model was established by injecting AB1-B/c-LUC cells and monitored by in vivo imaging. Proteomic analysis of spheroids was conducted to identify proteins and pathways involved. ResultsHypoxia boosts CD73 and A2Br expression in Me cells, leading to adenosine production via CD73. In 3D co-cultures, AB680 lowered Me cell viability and enhanced activation of Jurkat T cells. In mice, combining aPD-1 therapy with A2Br or CD73 inhibitors strongly reduced tumor growth. Proteomics identified 93 proteins influenced by adenosine signaling through A2B. ConclusionTargeting the adenosine pathway alongside PD-1 blockade offers a promising new immunotherapy strategy for Me.

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Machine Learning Analysis to Define Cell Lineage in Leiomyosarcoma

van IJzendoorn, D. G. P.; Przybyl, J.; Hastie, T.; Bovee, J. V. M. G.; Matusiak, M.; van de Rijn, M.

2026-05-12 cancer biology 10.64898/2026.05.08.723931 medRxiv
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IntroductionCellular differentiation and lineage commitment are known to be associated with differences in DNA methylation. Leiomyosarcoma (LMS) is a tumor thought to originate from smooth muscle cells in the walls of vessels in the soft tissue (STLMS) or from the uterine myometrium (ULMS). Here, we identify the methylation signatures of normal smooth muscle cells from blood vessels and the uterine wall and compare these with those found in STLMS and ULMS. We hypothesized that these methylation signatures could be used to assign a smooth muscle subtype of origin to individual leiomyosarcomas, and that tumors of different origin would show biological differences with potential therapeutic relevance. MethodsTo define methylation profiles for smooth muscle from vessel walls versus those found in myometrium, EPIC methylation profiling was performed on DNA from 49 formalin-fixed paraffin-embedded (FFPE) normal smooth muscle samples. A supervised machine learning algorithm (Random Forest) was used to distinguish the methylation patterns of normal smooth muscle cells in vessel walls from those in the myometrium. The resulting classifier was applied to methylation data on 67 cases of LMS with corresponding bulk RNAseq data to identify which tumors showed a methylation signature most consistent with either blood vessel wall (LMSvessel) or myometrial smooth muscle (LMSwall). A custom signature matrix derived from scRNAseq data from 6 samples of LMS was used in CIBERSORTx analysis to compare the cellular composition of LMS cases with a vessel or uterine wall methylation signature. ResultsA high degree of correlation was found between the known site of origin for LMS (STLMS vs ULMS) and the methylation signature derived from different types of normal smooth muscle. LMSwall tumors compared to LMSvessel tumors had significantly higher activation of the PD-1 checkpoint pathway in RNAseq analysis. Digital flow cytometry by CIBERSORTx analysis showed an increased expression of transcriptomic signatures of several immune cell subtypes in LMSvessel tumors. ConclusionUsing a supervised machine learning approach we classified LMS samples as either showing a high similarity in methylation patterns to normal smooth muscle cells of either the vessel wall or the myometrium. We found a correlation between LMS showing either a "vessel" or "muscle wall" methylation signature and their site of origin, but notably we also identified some exceptions. When classified based on their methylation signature LMSwall and LMSvessel differed in their PD-1 pathway activation and in their predicted immune cell populations, suggesting potential implications for immunotherapeutic approaches.

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Determinants of cancer care delays in Kinshasa, Democratic Republic of the Congo (DRC)

Dusingize, J. C.; Zotova, N.; Kabarriti, R.; Sehrawat, K.; Babakazo, P.; Alisho, A. S.; Kasindi, F. L.; Yessoufou, I.; Yotebieng, M.

2026-05-26 oncology 10.64898/2026.05.19.26353550 medRxiv
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PURPOSE: Cancer outcomes in sub-Saharan Africa are driven by delayed diagnosis and treatment initiation. We evaluated the magnitude and determinants of diagnostic and treatment delays among cancer patients in Kinshasa, Democratic Republic of the Congo (DRC). METHODS: We conducted a hospital-based cross-sectional study of 460 adults with confirmed cancer at Nganda Hospital Center in Kinshasa, DRC. Two outcomes were assessed: delay from symptom onset to diagnosis and delay from diagnosis to treatment initiation. Log-normal regression models were fitted for each outcome to estimate adjusted geometric mean ratios (aGMRs) and 95% confidence intervals (CIs). Covariates included demographic, socioeconomic, clinical, behavioral, and stigma-related factors. RESULTS: The median age was 55 years, and 76.2% of participants were women. Overall, 55.0% of participants experienced symptom-to-diagnosis delays >6 months, and 49.4% experienced diagnosis-to-treatment delays >3 months. Older age was associated with longer diagnostic delay (aGMR 1.55, 95% CI 1.03-2.31) and treatment delay (1.51, 1.07-2.14). Unemployment was strongly associated with both diagnostic delay (1.68, 1.15-2.47) and treatment delay (2.27, 1.54-3.33), as was hepatitis B co-infection (1.88, 1.06-3.34 and 2.42, 1.15-5.11, respectively). Longer diagnostic delay was additionally associated with informal trading (1.99, 1.21-3.28), taxi or motorbike transport (1.92, 1.25-2.94), and smoking history (2.25, 1.03-4.91), while high cancer-stereotype stigma was associated with longer treatment delay (1.56, 1.04-2.34). CONCLUSION: Substantial delays exist across the DRC cancer care continuum, driven by socioeconomic vulnerability, transport barriers, hepatitis B co-infection, and cancer-related stigma. These findings highlight the need for integrated interventions to improve timely diagnosis and treatment initiation, including strengthening financial protection, decentralizing cancer services, and reducing stigma in cancer care.

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Multiomic dissection of HR+/HER2- invasive lobular breast carcinoma reveals mobilized yet dysfunctional anti-tumor immunity shaped by tumor-stroma crosstalk and impaired antigen presentation

Picard, M.; Finetti, P.; Guille, A.; Lumet, G.; Mescam, L.; Boudin, L.; Goncalves, A.; Bertucci, F.; Mamessier, E.

2026-05-29 cancer biology 10.64898/2026.05.28.728418 medRxiv
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ContextImmunotherapy based on immune checkpoint inhibitors (ICI) revolutionized the treatment of triple-negative (TN) breast carcinomas (BC), but remains more challenging in HR+/HER2- BCs. Because invasive lobular carcinomas (ILC) generally exhibit low immune infiltration, ICIs were largely overlooked in this pathological type. The only clinical trial of ICIs dedicated to ILCs showed disappointing results, notably in HR+/HER2- cases. The immune landscape of HR+/HER2- ILCs has been poorly described. High level of tumor-infiltrating lymphocytes (TIL) was associated with worse prognosis in HR+/HER2- ILCs. A better characterization of the immune landscape of HR+/HER2- ILCs could clarify the poor efficiency of ICIs and the negative prognostic value of TILs, and reveal complementary targets able to increase immunotherapy efficiency. MethodWe comprehensively characterized the immune landscape of HR+/HER2- ILCs, comparatively to HR+/HER2- invasive ductal carcinomas (IDC), by applying multi-omics and multi-scale analysis (gene expression at the bulk and single-cell levels, and protein-based spatial analysis) to clinical samples. ResultsWhile the overall level of immune infiltration was comparable between both pathological types, the quality of immune infiltrate differed markedly. Comparatively to HR+/HER2- IDCs, HR+/HER2- ILCs were enriched in immune cells and tertiary lymphoid structures with anti-tumor potential, presented more spatial proximity between cancer cells and CD8+ cytotoxic T cells, and stronger theorical vulnerability to ICIs. However, in HR+/HER2- ILCs, anti-tumor response was defective; CD8+ cytotoxic T cells failed to fully unleash their cytotoxic function and CD4+ helper T cells evidenced a pro-tumoral and naive phenotype. Furthermore, antigen-presenting compartment was defective, altogether embedded in a stronger immunosuppressive environment, enriched in immunoregulatory cancer-associated fibroblasts (iCAF). ConclusionThis study contributes to explain the lesser efficiency of PD-1/PD-L1-based ICIs in HR+/HER2-ILCs by comparison with HR+/HER2- IDCs, by shedding light on a complex ecosystem where tumor cells shape a distinctive stroma that contribute to prevent anti-tumor immune response activation. Altogether, our findings further support the rationale for combining iCAF-targeting strategy with an ad hoc immunotherapy (such as an anti-VTCN1/B7-H4 antibody-drug conjugates for example). Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=150 SRC="FIGDIR/small/728418v1_ufig1.gif" ALT="Figure 1"> View larger version (26K): org.highwire.dtl.DTLVardef@c62294org.highwire.dtl.DTLVardef@86392org.highwire.dtl.DTLVardef@c10748org.highwire.dtl.DTLVardef@c543da_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_ST_ABSWHAT IS ALREADY KNOWN ON THIS TOPICC_ST_ABSO_LIImmune cells infiltrate both HR+/HER2- IDC and HR+/HER2- ILC tumors, but current ICIs are less effective in HR+/HER2- ILCs than HR+/HER2- IDCs. C_LI WHAT THIS STUDY ADDSO_LIThe anti-tumor immune response is mobilized but not effective in HR+/HER2- ILCs. C_LIO_LIA complex ecosystem - composed of immunoregulatory cancer-associated fibroblasts, high levels of TGFa, prostaglandin, acidosis, and a lack of antigen-presenting cells - prevents anti-tumor CD8+ cytotoxic T cell activation in HR+/HER2- ILCs. C_LI HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE, OR POLICYO_LITargeting the PD-1/PD-L1 axis is not the appropriate therapeutic strategy for HR+/HER2- ILCs. A more complex approach should be considered, notably those combining other immune-based strategies and iCAF targeting, which may offer a better chance to eradicate HR+/HER2- ILC tumor cells. C_LI