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Durante, M.

Publications and source records attributed to Durante, M..

10 recordsLinked to original sources

Lymphoma response to chimeric antigen receptor T cell therapy is driven by endogenous tumor-reactive CD8⁺ T cells

CD19-directed chimeric antigen receptor T-cell (CAR-T) therapy induces durable remissions in a subset of patients with relapsed or refractory large B-cell lymphoma; however, most patients fail to respond or eventually relapse. By integrating whole-genome and transcriptome profiling of 54 patients with functional assays, syngeneic models, and mathematical modeling, we demonstrate that durable CAR-T efficacy requires cooperation between CAR-T cells and endogenous CD8 (eCD8) T cells recruited to join the attack on malignant cells. Tumors with biallelic loss of MHC class I or CD58 exhibited high genomic complexity, increased neoantigen burden, and resistance to CAR-T therapy. MHC-I-deficient lymphomas showed suboptimal response in immunocompetent hosts compared to wild type. Importantly, sustained responses in mice occurred only in the presence of eCD8 cells, whereas all CD8-depleted mice relapsed after initial CAR-T-mediated tumor regression. Patients and murine ELISPOT assays confirmed enhanced endogenous T-cell activation post-CAR-T. These findings reveal that CAR-T therapy functions not only as a cytotoxic modality but also as a catalyst for endogenous anti-tumor immunity.

cancer biology↗

Establishing label-free quantitative X-ray dose-response profiling by Holo-Tomographic Flow Cytometry

Flow cytometry (FC) offers multiparametric analysis capabilities that can quantify cellular damage after exposure to cytotoxic agents. Here, we present a comprehensive study establishing a label-free quantitative X-ray dose-response profiling using a novel FC modality based on 3D Quantitative Phase Imaging, termed Holo-Tomographic Flow Cytometry (HTFC). This approach enables fully label-free 3D refractive index (RI) measurements, allowing detailed and quantitative characterization of the biophysical properties and morphology of living cells exposed to X-rays. By analyzing datasets of 3D RI tomograms from cells irradiated at graded doses, we identify intracellular biophysical markers that define a robust X-ray dose-response curve. Validation against standard clonogenic survival assays on three model cancer cell lines reveal a high correlation (>90%). HTFC not only eliminates labeling and operator bias but also markedly reduces experimental time from 1-2 weeks to 24 hours, offering a fully automated and objective readout. While clonogenic survival remains the benchmark for radiosensitivity assessment, our findings establish HTFC as a powerful label-free platform for fast assessment of radiation damage. This technology paves the way for predictive biosensors that can capture patient-specific responses, thereby supporting the transition from conventional, uniform radiotherapy protocols to personalized treatment strategies.

biophysics↗

Plasma cell identity escape drives resistance to anti-BCMA T-cell-redirecting therapy in multiple myeloma

Chimeric antigen receptor T-cell (CART) and T-cell engager (TCE) therapies targeting B-cell maturation antigen (BCMA) are transforming the treatment landscape for relapsed multiple myeloma (MM). However, despite impressive initial response rates, most patients eventually relapse. To investigate this unmet medical need, we applied whole-genome sequencing (WGS) to MM cells from cohorts of 102 relapsed patients treated with anti-BCMA CART and TCE therapies. Several genomic alterations were associated with clinical outcomes, particularly primary refractoriness, including high genomic complexity and mutations in genes regulating plasma cell identity, which predicted resistance to therapy. Single-cell RNA sequencing further revealed that MM cells from refractory patients exhibited high proliferation signatures and reduced expression of TNFRSF17 (encoding BCMA), while were less enriched for plasma cell-associated transcriptional programs, a phenomenon we term "plasma cell identity escape." This profile was strongly associated with immune dysregulation of CD8 T cells including increased activation and exhaustion. This evolution of MM toward a more proliferative and lineage-divergent state, refractory to the anti-BCMA T-cell redirecting therapies, was functionally validated in preclinical MM mouse models. Collectively, our results comprehensively define the cellular and molecular mechanisms underlying primary resistance to anti-BCMA therapies.

cancer biology↗

CD38 biallelic loss is a recurrent mechanism of resistance to anti-CD38 antibodies in multiple myeloma.

Monoclonal antibodies targeting CD38 are a therapeutic mainstay in multiple myeloma (MM). While they have contributed to improved outcomes, most patients still experience disease relapse, and little is known about tumor-intrinsic mechanisms of resistance to these drugs. Antigen escape has been implicated as a mechanism of tumor cell evasion in immunotherapy. Yet, it is unknown whether MM cells can develop permanent resistance to anti-CD38 antibodies by acquiring genomic events leading to biallelic disruption of the CD38 gene locus. Here, by using whole genome and whole exome sequencing data from 701 newly diagnosed patients, 67 patients at relapse with naivety to anti-CD38 antibodies, and 50 patients collected at relapse following anti-CD38 antibodies. We report a loss of CD38 in 20% (10/50) of patients post-CD38 therapy, three of which exhibited a loss of both copies. Two of these cases showed convergent evolution where distinct subclones independently acquired similar advantageous variants. Functional studies on missense mutations involved in biallelic CD38 events revealed that two variants, L153H and C275Y, decreased binding affinity and antibody-dependent cellular cytotoxicity of the commercial antibodies Daratumumab and Isatuximab. However, a third mutation, R140G, conferred selective resistance to Daratumumab, while retaining sensitivity to Isatuximab. Clinically, patients with MM are often rechallenged with CD38 antibodies following disease progression and these data support a role for next generation sequencing to guide treatment selection.

cancer biology↗

Mutagenic impact and evolutionary influence of radiotherapy in hematologic malignancies

Ionizing radiotherapy (RT) is a widely used palliative and curative treatment strategy for malignancies. In solid tumors, RT-induced double strand breaks lead to the accumulation of indels, and their repair by non-homologous end-joining has been linked to the ID8 mutational signature in resistant cells. However, the extent of RT-induced DNA damage in hematologic malignancies and its impact on their evolution and interplay with commonly used chemotherapies has not yet been explored. Here, we interrogated 580 whole genome sequencing (WGS) from patients with large B-cell lymphoma, multiple myeloma, and myeloid neoplasms and identified ID8 only in relapsed disease. Yet, it was detected after exposure to both RT and mutagenic chemotherapy (i.e., platinum). Using WGS of single-cell colonies derived from treated lymphoma cells, we revealed a dose-response relationship between RT and platinum and ID8. Finally, using ID8 as a genomic barcode we demonstrate that a single RT-resistant cell may seed systemic relapse.

genomics↗

Induction of cytoplasmic dsDNA and cGAS-STING immune signaling after exposure of breast cancer cells to X-rays or high energetic carbon ions

Radiotherapy can trigger activation of the cGAS-STING axis via cytoplasmic dsDNA fragment induction. The activation of cGAS-STING initiates innate immune signaling mediated by interferon type-I that can contribute to eradicate the malignancy. The effect was shown to depend on the fractionation scheme employed. We hypothesized that the innate immune response can also depend on radiation quality because densely ionizing radiation, such as carbon ions, have different effects on DNA lesion quality. We show here that carbon ions induced a significantly higher yield of cytosolic dsDNA fragments per unit dose as compared to photons in an in vitro 4T1 breast cancer model. The higher efficiency also translated in expression and release of interferon-{beta} by the tumor cells. Cytoplasmic dsDNA fragments as well as interferon-{beta} release increased with doses up to 24 Gy and no differences for a fractionation scheme (3x8 Gy) were found as compared to the single high doses of photons. In conclusion, we found that the release of interferon-{beta} after radiation is increasing with the radiation dose up to 20 Gy and that carbon ions have the potential to elicit a strong innate immune signaling.

biophysics↗

FLASH Bragg-peak irradiation with a therapeutic carbon ion beam: first in vivo results

Background and purposeIn recent years, ultra-high dose rate (UHDR) irradiation has emerged as a promising innovative approach to cancer treatment. Characteristic feature of this regimen, commonly referred to as FLASH effect, demonstrated primarily for electrons, photons or protons, is the improved normal tissue sparing, while the tumor control is similar to the one of the conventional dose-rate (CDR) treatments. The FLASH mechanism is, however, unknown. One major question is whether this effect is maintained when using densely ionizing (high-LET) heavy nuclei. Materials and MethodsHere we report the effects of 20 Gy UHDR heavy ion irradiation in clinically relevant conditions, i.e., at high-LET in the spread-out Bragg peak (SOBP) of a 12C beam using an osteosarcoma mouse model. ResultsWe show that UHDR irradiation was less toxic in the normal tissue compared to CDR while maintaining tumor control. The immune activation was also comparable in UHDR and CDR groups. We observed that the gut microbiome was altered in mice injected with the tumor compared to healthy animals, but both UHDR and CDR exposures steered the metagenome toward a balanced state. ConclusionsThe results show that the FLASH effect is safe and effective in heavy ion therapy and provide an important benchmark for the current mechanistic FLASH models. Highlights- FLASH irradiation with SOBP carbon ions spares normal tissue in mouse - Tumor control, immune response, and gut microbioma changes are induced at the same extent both at conventional and ultra-high dose rate - FLASH carbon ion irradiation is a safe and effective alternative to conventional radiotherapy.

cancer biology↗

Timing antigenic escape in multiple myeloma treated with T-cell redirecting immunotherapies

Recent data highlight genomic events driving antigen escape as a recurring cause of chimeric antigen receptor T-cell (CAR-T) and bispecific T-cell engager (TCE) resistance in multiple myeloma (MM). Yet, it remains unclear if these events, leading to clonal dominance at progression, result from acquisition under treatment selection or selection of pre-existing undetectable clones. This differentiation gains importance as these immunotherapies progress to earlier lines of treatment, prompting the need for innovative diagnostic testing to detect these events early on. By reconstructing phylogenetic trees and exploring chemotherapy mutational signatures as temporal barcodes in 11 relapsed refractory MM patients with available whole genome sequencing data before and after CART/TCE treatment, we demonstrated that somatic antigen escape mechanisms for BCMA- and GPRC5D-targeting therapies are acquired post-diagnosis, likely during CART/TCE treatment. Longitudinal tracking of these mutations using digital PCR in 4 patients consistently showed that genomic events promoting antigen escape were not detectable during the initial months of therapy but began to emerge nearly 1 year post therapy initiation. This finding reduces the necessity for a diagnostic panel to identify these events before CART/TCE. Instead, it underscores the importance of surveillance and identifying patients at higher risk of acquiring these events. KEY POINTSO_LIGenomic events driving antigen escape are recurrent mechanisms of resistance to CART and T-cell engagers in multiple myeloma. C_LIO_LIUsing chemotherapy mutational signatures, we demonstrated that these events are most likely acquired during treatment. C_LI

genomics↗

Ionizing radiation responses are incidental to desiccation responses in the bdelloid rotifer Adineta vaga

BackgroundThe remarkable resistance to ionizing radiation found in anhydrobiotic organisms, such as some bacteria, tardigrades, and bdelloid rotifers has been hypothesized to be incidental to the desiccation resistance. Both stresses produce reactive oxygen species and cause damage to DNA and other macromolecules. However, this hypothesis has only been investigated in a few species. ResultsIn this study, we analyzed the transcriptomic response of the bdelloid rotifer Adineta vaga to desiccation and to low- (X-rays) and high- (Fe) LET radiation to highlight the molecular and genetic mechanisms triggered by both stresses. We identified numerous genes encoding antioxidants, but also chaperones, that are constitutively highly expressed, which may contribute to the protection of proteins against oxidative stress during desiccation and ionizing radiation. We also detected a transcriptomic response common to desiccation and ionizing radiation with the over-expression of genes mainly involved in DNA repair and protein modifications but also genes with unknown functions being bdelloid-specific. A distinct transcriptomic response specific to rehydration was also found, with the over-expression of genes mainly encoding Late Embryogenesis Abundant proteins, specific Heat Shock Proteins, and glucose repressive proteins. ConclusionsThese results suggest that the extreme resistance of bdelloid rotifers to radiation might indeed be a consequence of their capacity to resist complete desiccation. This study paves the way to functional genetic experiments on A. vaga targeting promising candidate proteins playing central roles in radiation and desiccation resistance.

molecular biology↗

FRESH™ 3D bioprinted cardiac tissue, a bioengineered platform for in-vitro toxicology and pharmacology

There is critical need for a predictive model of human cardiac physiology in the drug development process for assessment of compound toxicology and pharmacology. In vitro two-dimensional monolayer culture of cardiomyocytes provides biochemical and cellular readouts, and in vivo small and large animal models provide information on systemic cardiovascular response. However, there remains a significant gap in these models due to an incomplete recapitulation of adult human cardiovascular physiology, which results in more difficult safety interpretations. Recent efforts in developing in vitro models from engineered heart tissues have demonstrated potential for bridging this gap using human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM) in a three-dimensional tissue structure. Here we advance this paradigm by implementing FRESH 3D bioprinting to build human cardiac tissues in a medium throughput, well-plate format with controlled tissue architecture, tailored cellular composition, and native-like physiological function, specifically in its adrenergic agonist drug response. To do this, we combined hiPSC-CMs, endothelial cells and fibroblasts in a cellular bioink and FRESH 3D bioprinted this mixture in the format of a thin tissue strip stabilized on a tissue fixture. Our results confirmed that FRESH 3D bioprinted cardiac tissues could be fabricated directly in a 24-well plate format, were composed of dense and highly aligned hiPSC-CMs at >600 million cells/mL, and within 14 days demonstrated reproducible calcium transients and fast conduction velocity of [~]25 cm/s. Interrogation of these cardiac tissues with the {beta}-adrenergic receptor agonist isoproterenol showed native-like positive chronotropic and inotropic responses, a combination of responses that is not typically observed in 2D monolayer models or standard 3D engineered heart tissue approaches. These results confirm that FRESH 3D bioprinted cardiac tissues represents a novel in vitro platform that enables early in vitro pharmacology and toxicology screening.

bioengineering↗