Category Archives: Scientific contents

Undifferentiated pleomorphic sarcoma (UPS) is one of the most common—and most aggressive—subtypes of soft tissue sarcoma (STS). Despite optimal treatment in localized stages, nearly half of patients ultimately develop metastatic disease, which drives poor outcomes.

To better understand the mechanisms underlying UPS metastasis, a team led by Prof. Antoine Italiano (Institut Bergonié, University of Bordeaux, INSERM U1312 BRIC) performed an integrated multi-omics analysis of paired primary and metastatic UPS samples, followed by functional validation in relevant patient-derived models.

Spatial biology (Explicyte)

As part of this work, Explicyte performed spatial transcriptomic profiling using the GeoMx Digital Spatial Profiler (Whole Transcriptome Atlas; >18K genes). The spatial analyses were conducted on 3 paired primary tumors and matched metastases enabling a direct comparison of tumor and microenvironmental programs across disease stages.

Key observations included:

• Upregulation of hypoxia, glycolysis, and EMT-related programs in metastases, consistent with a more aggressive, metastasis-associated biology.


• Enrichment of endothelial-cell signatures in metastatic samples, suggesting increased angiogenesis compared with primary tumors.


• Higher immune infiltration in primary tumors (including CD8+ T cells, NK cells, and memory B cells), supporting the notion of a more immune-suppressive / immune-excluded state in metastatic lesions.

To further support these findings, we confirmed a reduction in CD8+ T-cell infiltration in metastases using a multiplex immunohistofluorescence (mIHF) panel in five paired primary/metastatic cases.

Bulk RNAseq

In parallel, the team analyzed paired primary and metastatic tumor samples from 13 patients using bulk RNA-seq to capture global transcriptomic changes associated with metastatic progression. This analysis confirmed an enrichment of metastasis-associated pathways and identified 690 genes significantly altered between primary tumors and metastases. Among the top candidates, ADORA2B emerged as particularly compelling because:

• ADORA2B encodes a G protein–coupled adenosine receptor (A2B) implicated in metastatic progression in several epithelial cancers,


• ADORA2B is drug­gable, with inhibitors already being evaluated in clinical development programs.

Using public and third-party sarcoma datasets, the team further showed that ADORA2B is overexpressed in UPS and is associated with features of an immune-suppressive microenvironment in metastatic UPS—supporting ADORA2B as a promising therapeutic target in this indication.

Functional validation

To test whether ADORA2B plays a causal role in UPS aggressiveness, the authors generated ADORA2B knockout models using CRISPR-Cas9 in two patient-derived UPS cell lines.

• Transcriptomic profiling of ADORA2B-knockout cells confirmed downregulation of key pathways involved in metastatic biology.


• Functional assays demonstrated that ADORA2B loss reduces UPS cell proliferation, migration, and invasion, supporting a direct role in tumor aggressiveness.

The in vivo impact was then evaluated in Rag2-/- γc-/- mice:

• In an orthotopic model, tumors derived from ADORA2B-knockout cells showed markedly impaired growth, leading to significantly smaller, low-proliferating tumors compared with controls.


• In a forced metastasis model (tail-vein injection), ADORA2B-knockout cells produced substantially fewer metastases, translating into a striking survival benefit (100% survival in the knockout arm vs 0% in controls in this experimental setting).

Finally, the team evaluated a dual ADORA2A/ADORA2B inhibitor, M1069 (EMD Serono), currently assessed in early-phase trials. In vitro, M1069 reduced proliferation and invasion in UPS models, providing pharmacological support for the genetic findings.

Impact

Overall, this work identifies ADORA2B as a critical regulator of primary tumor growth and metastatic dissemination in UPS. It also highlights the therapeutic promise of targeting the adenosine axis, and specifically ADORA2B, as a strategy to disrupt metastatic progression and improve outcomes in this rare and aggressive cancer.

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This research received funding from the Agence Nationale de la Recherche  (“France 2030” / ANR 21 RHUS 0010).

We're glad to announce the publication of an immunology paper led by our colleagues at ImmunoConcEpT (CNRS/Université de Bordeaux) in Science Advances: "Immune control of functional memory CD8 T cells in normal-appearing vitiligo skin."

Using single-cell and spatial transcriptomics profiling of vitiligo patient biopsies, the team demonstrates that similar CD8+ T-cell clusters infiltrate both lesional and non-lesional skin. The difference lies in the “regulatory layer”: normal-appearing skin is characterized by an enrichment in immune regulatory pathways (increased Treg infiltration and higher PD-1 expression on CD8+ T cells), consistent with tighter regulation of inflammation.

Building on the Phase 2 BARVIT trial (NCT04822584), which showed a clinical benefit of baricitinib combined with phototherapy for repigmentation, ImmunoConcEpT partnered with Explicyte to perform a paired pre/post immune profiling of skin biopsies using our automated multiplex IF workflow.

Our multiplex IF data support the proposed mechanism; after 9 months of treatment, non-lesional skin exhibits:

• reduced CD8+ T-cell infiltration
• increased PD-1 on CD8+ T cells and PD-L1 on dendritic cells
• an increased FOXP3+ / CD8+ T-cell ratio

Together, these results highlight the critical role of immune regulatory mechanisms to prevent inflammation & depigmentation in vitiligo.

> Read the article

New paper out in Cancer Cell ! This collaboration with the Memorial Sloan Kettering Cancer Center (MSKCC), led by David Knorr and colleagues, shows that an Fc-optimized CD40 agonist (2141-V11), delivered intratumorally, can induce tertiary lymphoid structures (TLS) and drive systemic antitumor immunity—with complete responses reported in melanoma and breast cancer.

Beyond the headline result, these findings reinforce a key idea: TLS can be pursued as a therapeutic objective—with the right engineering and delivery, CD40 agonism can reprogram the tumor microenvironment into a self-sustaining immune ecosystem.

Explicyte supported this work with multiplex IHF staining, enabling direct visualization of TLS formation in tumor tissue. This study highlights how our translational research platform helps partners measure and interpret the impact of new immunomodulatory agents—from TLS induction and maturation to dendritic-cell activation, HEV density, and chemokine programs—leveraging spatial biology + multiplex IHF with integrated analytics.

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Soft-tissue sarcomas (STS) usually resist immune-checkpoint blockade because their micro-environment is both poorly immunogenic and actively immunosuppressive. To convert these “cold” into “hotter,” immune-responsive tumors, the phase II REGOMMUNE trial —led by Prof. Antoine Italiano at Institut Bergonié and Gustave Roussy—combined the multi-kinase anti-angiogenic agent regorafenib with the anti-PD-L1 antibody avelumab.

Between 2019 and 2021, 50 patients with advanced STS lacking mature tertiary lymphoid structures (TLS) were enrolled to test whether this strategy could boost immune-cell infiltration and improve anti-tumour activity.

 

Key findings published in Signal Transduction & Targeted Therapy

Modest efficacy, manageable safety

• Efficacy:  Of the 43 TLS-negative patients who were assessable, the objective response rate was 11.4 % (all partial responses), whereas 50 % progressed on treatment. Median progression-free survival was 1.8 months.


• Safety: Forty-nine patients received at least one dose of either regorafenib or avelumab and were included in the safety analysis. Toxicities were generally low-grade and controllable; importantly, no treatment-related deaths occurred, indicating that the combination is well tolerated.

 

Plasma proteomics: stronger immune signals but red flags for checkpoint resistance

Associated to this study through the RHU CONDOR, Explicyte profiled paired plasma samples (baseline → Cycle 2 Day 1) from 32 STS patients receiving regorafenib + avelumab with the Olink Explore HT panel (5300 proteins):

• Immune-cell influx: Gene-ontology analysis of up-regulated proteins showed marked enrichment of CD8⁺ T-cell and B-cell signatures.


• Soluble PD-L1 surge: Soluble PD-L1 (CD274) —a known negative predictor of response to PD-(L)1 blockade—was the most strongly up-regulated protein.


• Tryptophan depletion: complementary metabolomics showed a pronounced drop in circulating L-tryptophan, a metabolic hallmark of immune activation.

 

Digital pathology: deeper—yet still not optimal—immune engagement

Explicyte ran multiplex immunofluorescence on paired biopsies from seven STS patients (pre- vs. Cycle 2 Day 1), corroborating the plasma data but also exposing barriers to efficacy:

• More lymphocytes: Intratumoral CD8⁺ T-cell and CD20⁺ B-cell densities rose in respectively 6 and 4 patients, yet progressive disease occurred in patients with the highest increases in CD8+ T and B cell density, showing that infiltration alone is insufficient to trigger clinical benefit.


• No TLS formation: Lymphocytes failed to organise into productive immune niches.


• Immunosuppressive myeloid niche: The density of M2-polarised macrophages increased, likely damping cytotoxic activity.


• Adaptive PD-1 up-shift: Post-treatment T cells displayed higher PD-1 expression, suggesting re-engagement of the PD-1/PD-L1 axis and a mechanism of resistance to avelumab.

 

Read the full paper