Publications by authors named "Letouze E"

The CRCINA inaugural symposium, a meeting on tumor and immune ecosystems, took place in the vibrant and picturesque city of Nantes. The meeting gathered world-renowned experts in cancer biology and immunology. It showcased the most advanced science on mechanisms driving cellular heterogeneity, plasticity, and signaling in normal and cancer cellular ecosystems, which contribute to cancer development, progression, and therapeutic resistance.

View Article and Find Full Text PDF
Article Synopsis
  • Hepatoblastomas show varied cell types that affect patient outcomes, but the reasons for this diversity are not well understood.
  • Researchers employed a single-cell analysis to explore the molecular factors contributing to these different cell states, revealing a spectrum of differentiation between liver cell types.
  • They discovered that specific genetic subclones within tumors exhibit unique levels of cellular flexibility, with certain subclones being more aggressive and responsive to chemotherapy due to the overexpression of specific genes.
View Article and Find Full Text PDF

Bispecific T-cell engagers (TCEs) are revolutionizing patient care in multiple myeloma (MM). These monoclonal antibodies, that redirect T cells against cancer cells, are now approved for the treatment of triple-class exposed relapsed/refractory MM (RRMM). They are currently tested in earlier lines of the disease, including in first line.

View Article and Find Full Text PDF

Pediatric liver tumors are very rare tumors with the most common diagnosis being hepatoblastoma. While hepatoblastomas are predominantly sporadic, around 15% of cases develop as part of predisposition syndromes such as Beckwith-Wiedemann (11p15.5 locus altered).

View Article and Find Full Text PDF

Bispecific antibodies targeting GPRC5D demonstrated promising efficacy in multiple myeloma, but acquired resistance usually occurs within a few months. Using a single-nucleus multi-omic strategy in three patients from the MYRACLE cohort (ClinicalTrials.gov registration: NCT03807128 ), we identified two resistance mechanisms, by bi-allelic genetic inactivation of GPRC5D or by long-range epigenetic silencing of its promoter and enhancer regions.

View Article and Find Full Text PDF

Somatic mutations can disrupt splicing regulatory elements and have dramatic effects on cancer genes, yet the functional consequences of mutations located in extended splice regions is difficult to predict. Here, we use a deep neural network (SpliceAI) to characterize the landscape of splice-altering mutations in cancer. In our in-house series of 401 liver cancers, SpliceAI uncovers 1244 cryptic splice mutations, located outside essential splice sites, that validate at a high rate (66%) in matched RNA-seq data.

View Article and Find Full Text PDF

While the fighting in the Syrian civil war has mostly stopped, an estimated 5.6 million Syrians remain living in neighboring countries. Of these, an estimated 1.

View Article and Find Full Text PDF

Unlabelled: Intercensal estimates of access to electricity and clean cooking fuels at policy planning microregions in a country are essential for understanding their evolution and tracking progress towards Sustainable Development Goals (SDG) 7. Surveys are prohibitively expensive to get such intercensal microestimates. Existing works, mainly, focus on electrification rates, make predictions at the coarse spatial granularity, and generalize poorly to intercensal periods.

View Article and Find Full Text PDF

Purpose: Mongolia has the world's highest incidence of hepatocellular carcinoma (HCC), with ∼100 cases/100,000 inhabitants, although the reasons for this have not been thoroughly delineated.

Experimental Design: We performed a molecular characterization of Mongolian (n = 192) compared with Western (n = 187) HCCs by RNA sequencing and whole-exome sequencing to unveil distinct genomic and transcriptomic features associated with environmental factors in this population.

Results: Mongolian patients were younger, with higher female prevalence, and with predominantly HBV-HDV coinfection etiology.

View Article and Find Full Text PDF

Background & Aims: Acute intermittent porphyria (AIP), caused by heterozygous germline mutations of the heme synthesis pathway enzyme HMBS (hydroxymethylbilane synthase), confers a high risk of hepatocellular carcinoma (HCC) development. Yet, the role of HMBS in liver tumorigenesis remains unclear.

Methods: Herein, we explore HMBS alterations in a large series of 758 HCC cases, including 4 patients with AIP.

View Article and Find Full Text PDF

The persistence of cancer cells resistant to therapy remains a major clinical challenge. In triple-negative breast cancer, resistance to chemotherapy results in the highest recurrence risk among breast cancer subtypes. The drug-tolerant state seems largely defined by nongenetic features, but the underlying mechanisms are poorly understood.

View Article and Find Full Text PDF

Unlabelled: Oncogene activation leads to replication stress and promotes genomic instability. Here we combine optical mapping and whole-genome sequencing (WGS) to explore in depth the nature of structural variants (SV) induced by replication stress in cyclin-activated hepatocellular carcinomas (CCN-HCC). In addition to classical tandem duplications, CCN-HCC displayed frequent intra-chromosomal and interchromosomal templated insertion cycles (TIC), likely resulting from template switching events.

View Article and Find Full Text PDF

Introduction: Among the different mechanisms of acquired resistance to EGFR tyrosine kinase inhibitors (TKIs) reported in EGFR-mutated lung adenocarcinoma (EGFR-LUAD) patients, histological transformation into small cell carcinoma (SCLC) occurs in 3-14% of resistant cases, regardless of the generation of EGFR-TKI. In recent studies, bi-allelic inactivation of TP53 and RB1 has been identified in a vast majority of transformed SCLCs. However, the molecular mechanisms driving this histologic transformation remain largely unknown, mainly due to the rarity of samples.

View Article and Find Full Text PDF
Article Synopsis
  • The study looked into the genetic causes of a condition called food-dependent Cushing syndrome (FDCS) in patients with a specific type of adrenal gland problem.
  • Researchers analyzed samples from 36 patients to find out more about their genes.
  • They discovered that a gene called KDM1A is important for understanding FDCS, and testing for both KDM1A and another gene called ARMC5 can help doctors diagnose and treat patients better.
View Article and Find Full Text PDF

Background: Hepatocellular carcinoma is a frequent consequence of alcohol-related liver disease, with variable incidence among heavy drinkers. We did a genome-wide association study (GWAS) to identify common genetic variants for alcohol-related hepatocellular carcinoma.

Methods: We conducted a two-stage case-control GWAS in a discovery cohort of 2107 unrelated European patients with alcohol-related liver disease aged 20-92 years recruited between Oct 22, 1993, and March 12, 2017.

View Article and Find Full Text PDF
Article Synopsis
  • Retinoblastoma is the most common eye cancer in children, originating from developing retinal cells, but its molecular behavior is not well understood.* -
  • Researchers identified two distinct subtypes of retinoblastoma: Subtype 1 is characterized by early onset and less genetic alteration, while Subtype 2 has recurrent genetic changes, is less differentiated, and has a higher likelihood of spreading.* -
  • Understanding these two subtypes can offer new insights into the biology and treatment of retinoblastoma, with subtype 1 being less aggressive and subtype 2 showing more aggressive traits and stem cell-like features.*
View Article and Find Full Text PDF

Background And Aims: Despite the epidemiological association between intrahepatic cholangiocarcinoma (iCCA) and HBV infection, little is known about the relevant oncogenic effects. We sought to identify the landscape and mechanism of HBV integration, along with the genomic architecture of HBV-infected iCCA (HBV-iCCA) tumors.

Approach And Results: We profiled a cohort of 108 HBV-iCCAs using whole-genome sequencing, deep sequencing, and RNA sequencing, together with preconstructed data sets of HBV-infected HCC (HBV-HCC; n = 167) and combined hepatocellular cholangiocarcinoma (HBV-cHCC/CCA; n = 59), and conventional (n = 154) and fluke-related iCCAs (n = 16).

View Article and Find Full Text PDF

Background: Malignant pleural mesothelioma (MPM) is a heterogeneous cancer. Better knowledge of molecular and cellular intra-tumor heterogeneity throughout the thoracic cavity is required to develop efficient therapies. This study focuses on molecular intra-tumor heterogeneity using the largest series to date in MPM and is the first to report on the multi-omics profiling of a substantial series of multi-site tumor samples.

View Article and Find Full Text PDF

Succinate dehydrogenase is a key enzyme in the tricarboxylic acid cycle and the electron transport chain. All four subunits of succinate dehydrogenase are tumor suppressor genes predisposing to paraganglioma, but only mutations in the SDHB subunit are associated with increased risk of metastasis. Here we generated an knockout chromaffin cell line and compared it with deficient cells.

View Article and Find Full Text PDF
Article Synopsis
  • Pediatric liver cancers (PLC) are diverse diseases that affect younger populations, showing varying responses to chemotherapy despite generally favorable outcomes.
  • A genomic study of 126 pediatric liver tumors revealed new targetable oncogenes and identified a specific premalignant cell expansion in 10% of hepatoblastoma patients younger than three years old.
  • Research highlighted the accumulation of mutations in "liver progenitor" cells during chemotherapy, leading to cisplatin resistance, and validated promising new treatments through drug screening and xenograft experiments.
View Article and Find Full Text PDF

Georeferenced digital trace data offer unprecedented flexibility in migration estimation. Because of their high temporal granularity, many migration estimates can be generated from the same data set by changing the definition parameters. Yet despite the growing application of digital trace data to migration research, strategies for taking advantage of their temporal granularity remain largely underdeveloped.

View Article and Find Full Text PDF

Background And Aims: DNA methylation patterns are highly rearranged in HCCs. However, diverse sources of variation are intermingled in cancer methylomes, precluding the precise characterization of underlying molecular mechanisms. We developed a computational framework (methylation signature analysis with independent component analysis [MethICA]) leveraging independent component analysis to disentangle the diverse processes contributing to DNA methylation changes in tumors.

View Article and Find Full Text PDF