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Derieppe, M.-A.

Publications and source records attributed to Derieppe, M.-A..

4 recordsLinked to original sources

Microbiota-gut-brain axis modulation drives glioblastoma progression and therapy resistance

Glioblastoma is a highly aggressive brain tumour with poor prognosis, whose aetiology, progression, and therapeutic resistance remain incompletely understood. While the microbiota-gut-brain axis has emerged as a key regulator of neurological disorders, its role in glioblastoma biology and treatment response is still largely unexplored. Using a clinically relevant immunocompetent murine model combining glioblastoma stem cell implantation, dextran sodium sulfate-induced gut inflammation, and a full Stupp-like therapeutic protocol, we investigated bidirectional gut-brain communication in glioblastoma. Tumour growth and recurrence were monitored by bioluminescence imaging, tumour transcriptomic profiles were analysed by RNA sequencing, and brain and colon tissues were subjected to histological and molecular analyses. Gut microbiota composition was assessed by 16S rRNA sequencing, while systemic metabolites and cytokines were quantified in plasma. Cross-compartment association bioinformatic analyses were performed to correlate multi-organ readouts. Gut inflammation enhanced glioblastoma growth and promoted tumour recurrence following therapy. Tumour progression was associated with increased infiltration of immunosuppressive macrophages, whereas recurrence correlated with elevated oxidative DNA damage. Remarkably, glioblastoma exerted systemic immunomodulatory effects, attenuating intestinal and systemic inflammatory responses, and induced profound remodelling of gut microbiota composition and predicted metabolic function, including enrichment of Akkermansia and depletion of Lactobacillus. Systemic metabolic profiling was investigated as a route of communication within the gut-brain axis and revealed adaptations in DSS-treated mice associated with tumour burden and therapeutic response. Multi-compartment correlation and multivariable association analyses identified specific bacterial genera and circulating metabolites associated with tumour volume, intestinal inflammation, and genomic instability. These findings uncover a dynamic, bidirectional microbiota-gut-brain axis in glioblastoma and identify intestinal inflammation as a critical determinant of tumour progression and therapeutic outcome. Targeting gut disturbances and microbiota-associated metabolic pathways may represent novel strategies to modulate glioblastoma aggressiveness and treatment response.

cancer biology↗

TREM1+ regulatory myeloid cells expand in steatohepatitis-HCC and associate with poor prognosis and therapeutic resistance to anti-PD-1 blockade

Hepatocellular carcinoma (HCC) is an inflammation-associated cancer arising from viral and non-viral etiologies. Immune checkpoint blockade primarily benefits patients with viral HCC. Expansion of suppressive myeloid cells is a hallmark of chronic inflammation and cancer, but their heterogeneity in HCC is not fully resolved and might underlie immunotherapy resistance in the steatohepatitis setting. Here, we present a high resolution atlas of hepatic innate immune cells from patients with HCC that unravels a steatohepatitis contexture characterized by the emergence of high entropy myeloid cell states and myeloid-biased NK cell differentiation. We identify a discrete population of tumor-infiltrating myeloid cells, predominant in the steatohepatitis setting, that expresses a variety of myeloid lineage-affiliated genes, including granulocyte, macrophage and dendritic cell features, and can be identified in HCC tumors based on selective dual expression of TREM1 and CD163. Functional characterization reveals that TREM1+ CD163+ myeloid cells highly express TGF{beta} and IL-13RA, localize to HCC fibrotic lesions, and potently suppress T cell effector functions ex vivo, a function further potentiated by TREM1 engagement. We refer to this population as TREM1+ CD163+ regulatory myeloid cells (TREM1+CD163+ Mreg). Deconvolution analyses in large cohorts of patients with HCC and other solid tumors reveals that the density of TREM1+ CD163+ Mreg increases in advanced stages, associates with poor prognosis, and therapeutic resistance to PD-1 blockade. Our data support myeloid subset-targeted immunotherapies to treat HCC and identify TREM1 as a therapeutic target. HIGHLIGHTSO_LIAtlas of hepatic innate immune cells (100,000 transcriptomes) from patients with HCC C_LIO_LICore signatures to identify, discriminate and localize innate lymphoid and myeloid cells C_LIO_LIA population of TREM1+CD163+ myeloid cells, referred to as TREM1+CD163+ Mreg, expands in steatohepatitis HCC C_LIO_LITREM1+CD163+ Mreg express granulocyte- and macrophage/dendritic cell-lineage genes C_LIO_LITREM1+CD163+ Mreg potently suppress T cell effector functions, which is potentiated by TREM1 engagement by cognate ligands C_LIO_LITREM1+CD163+ Mreg produce high levels of TGF{beta} and populate fibrotic lesions C_LIO_LIThe density of TREM1+CD163+ Mreg increases in advanced HCC and associate with poor patient survival C_LIO_LIThe density of TREM1+CD163+ Mreg associates with resistance to immune checkpoint blockade in other solid tumors C_LI

immunology↗

Paternal multigenerational exposure to an obesogenic diet drives epigenetic predisposition to metabolic disorders

Obesity is a growing societal scourge responsible for approximately 4 million deaths worldwide. Recent studies have uncovered that paternal excessive weight induced by an unbalanced diet affects the metabolic health of offspring. These reports mainly employed single-generation male exposure. However, the consequences of multigenerational unbalanced diet feeding on the metabolic health of progeny remain largely unknown. Here, we show that maintaining paternal western diet feeding for five consecutive generations in mice induces a gradual enhancement in fat mass and related metabolic diseases over generations. Strikingly, chow-diet-fed progenies from these multigenerational western-diet-fed males develop a "healthy" overweight phenotype that is not reversed after 4 subsequent generations. Mechanistically, sperm RNA microinjection experiments into zygotes suggest that sperm RNAs are sufficient for establishment but not for long-term maintenance of epigenetic inheritance of metabolic pathologies. Progressive and permanent metabolic deregulation induced by successive paternal western-diet-fed generations may contribute to the worldwide epidemic of metabolic diseases.

genetics↗

A multi-layered systems approach for renal cell carcinoma

Renal cell carcinoma (RCC) still lacks prognostic and predictive biomarkers to monitor the disease and the response to therapy. The usual strategy in translational research is to start from human samples, to identify molecular markers and gene networks and then to functionally validate them in vitro and in animal models. We devised herein a completely opposite strategy from "mouse to man" by performing an aggressiveness screen and used functional genomics, imaging, clinical data and computational approaches in order to discover molecular pathways and players in renal cancer development and metastasis. Multiple cell lines for primary tumor growth, survival in the blood circulation and lung metastasis or metastatic spread from the primary tumor were generated and analyzed using a multi-layered approach which includes large-scale transcriptome, genome and methylome analyses. Transcriptome and methylome analyses demonstrated distinct clustering in three different groups. Remarkably, DNA sequencing did not show significant genomic variations in the different groups which indicates absence of clonal selection during the in vivo amplification process. Transcriptome analysis revealed distinct signatures of tumor aggressiveness which were validated in patient cohorts. Methylome analysis of full-length DNA allowed clustering of the same groups and revealed clinically relevant signatures. Furthermore, we identified SAA2 and CFB as soluble prognostic and predictive biomarkers of the therapeutic response. We also uncovered IL34 as another soluble prognostic biomarker and key regulator of renal cell carcinoma (RCC) progression. This was also functionally validated in vivo, and a mathematical model of IL34-dependent primary tumor growth and metastasis development was provided. These results indicate that such multilayered analysis in a RCC animal model leads to meaningful results that are of translational significance. One Sentence SummaryAn aggressiveness screen with multilayer systems analysis to identify signatures and biomarkers for renal cell carcinoma aggressiveness.

cancer biology↗