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Corre, J.

Publications and source records attributed to Corre, J..

6 recordsLinked to original sources

Sequential acquisition of 1p31.1-p12 LOH and 1q Gain is a common double-hit event in relapsed/refractory myeloma

Therapy-driven genomic changes in multiple myeloma (MM) remain poorly defined. We analyzed whole-genome sequencing (WGS) data from relapsed/refractory MM (rrMM, N=386) and identified regional 1p31.1-p12 (hereafter 1pCEN, a region proximal to the centromere) loss-of-heterozygosity (LOH) as the only enriched aberration showing strong therapy-associated clonal selection (clonal timing rank fold-change = 3.7, P<2.2x10-16). This event showed enriched co-occurrence with 1qGain (OR = 2.3 (1.5-3.8), P=2x10-4) forming a recurrent "double-hit" in rrMM. To validate the clonal selection process, we examined three longitudinal cohorts (180 patients, 390 samples) and confirmed clonal expansion of 1pCEN and consistent prevalence of the 1pCEN+1q double-hit (20-24%). Survival analyses demonstrated significantly reduced progression-free survival in rrMM patients with this double-hit compared with those without. Comparison with a large newly diagnosed MM (ndMM) cohort confirmed previously-described 1p32 LOH is the prognostic locus at baseline, whereas 1pCEN is therapy-selected and largely independent of the 1p32 locus. Thus, 1pCEN+1q represents a recurrent double-hit event that clonally emerges in rrMM, conferring selective advantage under drug exposure and is distinct from the ndMM high-risk markers defined by current consensus guidelines. These findings nominate 1pCEN as a new genomic biomarker in rrMM and 1pCEN+1q may help patient stratification for therapeutic monitoring. Key PointsA therapy-driven common genomic double-hit (1p31.1-p12 LOH with 1q gain) clonally emerges in relapsed/refractory myeloma.

cancer biology↗

Expression profile of CASSIOPEIA patients refines prognostic value of MRD negativity in multiple myeloma

Long-term follow-up of the CASSIOPEIA trial (NCT02541383) demonstrated superior progression-free survival (PFS) with daratumumab, both in combination with bortezomib, thalidomide, and dexamethasone during induction and consolidation, and during maintenance therapy, in transplant- eligible patients newly diagnosed with multiple myeloma (MM). However, outcomes among CASSIOPEIA patients remain heterogeneous across treatment groups. Measurable residual disease (MRD) is a strong indicator of the depth and duration of therapeutic response and is independently associated with both PFS and overall survival (OS), but it does not fully capture the biological diversity of MM. We performed a risk prediction analysis based on transcriptomic subgroups in CASSIOPEIA patients. A subset of 628 patients was characterized using RNA sequencing and consensus clustering identified five transcriptomic subtypes of MM. Long-term follow-up allowed the definition of three transcriptomic risk categories, with estimated 72-month PFS rates of 70%, 51%, and 27% for low, intermediate, and high-risk groups, respectively, among patients who received daratumumab in at least one treatment phase. In these patients, MRD negativity rates after consolidation and six months later were significantly higher in the low and high-risk groups compared with the intermediate-risk group. In the high-risk group, MRD status was not associated with PFS or OS. This suggests that, although daratumumab administered during both the induction/consolidation and maintenance phases improves the clinical outcomes of patients with activation of NSD2 or overexpressing members of the MAF family, highly aggressive minor clones may rapidly expand. These findings emphasize the need for novel therapeutic strategies in this high-risk population.

cancer biology↗

Inflamed Natural Killer cells with adhesion defects are associated with a poor prognosis in Multiple Myeloma

The promising results obtained with immunotherapeutic approaches for multiple myeloma (MM) call for a better stratification of patients based on immune components. The most pressing being cytotoxic lymphocytes such as Natural Killer (NK) cells that are mandatory for MM surveillance and therapy. In this study, we performed a single cell RNA sequencing analysis of NK cells from 10 MM patients and 10 age/sex matched healthy donors (HD) that revealed important transcriptomic changes in NK cell landscape affecting both the bone marrow and peripheral blood compartment. The frequency of mature cytotoxic "CD56dim" NK cell subsets was reduced in MM patients at the advantage of late-stage NK cell subsets expressing NF{kappa}B and IFN-I inflammatory signatures. These NK cell subsets accumulating in MM patients were characterized by a low CD16 and CD226 expression and poor cytotoxic functions. MM CD16/CD226lo NK cells also had adhesion defects with reduced LFA-1 integrin activation and actin polymerization that may account for their limited effector functions in vitro. Finally, analysis of BM infiltrating NK cells in a retrospective cohort of 177 MM patients from the IFM 2009 trial demonstrated that a high frequency of NK cells and their low CD16 and CD226 expression were associated with a shorter overall survival. Thus, CD16/CD226lo NK cells with reduced effector functions accumulate along MM development and negatively impact patients clinical outcome. Given the growing interest in harnessing NK cells to treat myeloma, this improved knowledge around MM-associated NK cell dysfunction will stimulate the development of more efficient immunotherapeutic drugs against MM. Scientific category: Lymphoid Neoplasia; Immunobiology and Immunotherapy. KEY POINTSO_LIMM patients have increased CD16/CD226low NK cell subsets characterized by "inflammatory" signatures and reduced effector functions. C_LIO_LIThe frequency of CD16/CD226low NK cells correlate with MM patient clinical outcome C_LI

immunology↗

Unsupervized identification of prognostic copy-numberalterations using segmentation and lasso regularization

Identifying copy-number alteration with prognostic impact is typically done in a supervised approach, were candidate regions are user-selected (chomosome arms, oncogenes, etc). Yet CNA events may range from whole chromosome alterations to small focal amplifications or deletions, with no available approach to combine the potential prognostic impact of different aberration ranges. We propose and compare different statistical models to integrate the effects of multi-scale CNA events by exploiting the longitudinal structure of the genome, and assume that the survival distribution follows a Cox-proportional hazard model. These methods are adaptable to any cohorts screened for CNA by genome-wide assays such as CGH-array or whole-genome sequencing technologies, and with sufficient follow-up time. We show that combining a segmentation in the survival odds strategy with a lasso-regularization selection approach provides the best results in terms of recovering the true significant CNA regions as well as predicting survival outcomes. In particular, as shown on a 551 Multiple Myeloma patient cohort, this method allows to refine previously identified regions to exhibit potential novel driver genes.

bioinformatics↗

Yellow adipocytes comprise a new adipocyte sub-type present in human bone marrow

During energy demanding conditions, white adipocytes store triglycerides and release fatty acids through lipolysis. In contrast, bone marrow adipocytes (BM-Ad) increase in size during caloric restriction, suggesting this fat depot exhibits precise metabolic specificity. We found subcutaneous adipocytes (SC-Ad) and BM-Ad share morphological features, but possess distinct lipid metabolism. BM-Ad show enrichment in cholesterol-oriented metabolism that correlates with increased free cholesterol content, while proteins involved in lipolysis were downregulated. A strong down-regulation in expression of monoacylglycerol (MG) lipase was observed leading to an accumulation of major MG species and accordingly the basal and induced lipolytic responses were absent in BM-Ad. These features are not recapitulated in vitro using differentiated bone marrow mesenchymal stem cells. Since our data demonstrate that BM-Ad comprise a distinct class of adipocytes, we propose renaming them yellow adipocytes.

physiology↗

Dopamine neurons projecting to medial shell of the nucleus accumbens drive heroin reinforcement

The dopamine (DA) hypothesis posits the increase of mesolimbic dopamine levels as a defining commonality of addictive drugs, initially causing reinforcement, eventually leading to compulsive consumption. While much experimental evidence from psychostimulants supports this hypothesis, it has been challenged for opioid reinforcement. Here, we use genetically encoded DA and calcium indicators as well as cFos to reveal that heroin activates DA neurons located in the medial part of the VTA, preferentially projecting to the medial shell of the nucleus accumbens (NAc). Chemogenetic and optogenetic manipulations of VTA DA or GABA neurons establish a causal link to heroin reinforcement. Inhibition of DA neurons blocked heroin self-administration, while heroin inhibited optogenetic self-stimulation of DA neurons. Likewise, heroin occluded the self-inhibition of VTA GABA neurons. Together, these experiments support a model of disinhibition of a subset of VTA DA neurons in opioid reinforcement.

neuroscience↗