Anal squamous cell carcinomas (ASCC) are rare tumours in humans. The etiological role of HPV infection is now well established but little is known about the molecular landscape and signalling ...pathways involved in the pathogenesis of this cancer. Here we report the results from a whole exome sequencing of a homogeneous group of 20 treatment-naive ASCC. A total of 2422 somatic single nucleotide variations (SNV) were found, with an overall moderate rate of somatic mutations per tumour (median: 105 relevant SNV per tumour) but a high mutational load in 3 tumours. The mutational signatures associated with age and APOBEC were observed in 100% and 60% of tumours respectively. The most frequently mutated genes were
(25%) followed by
(15%),
(15%)
and
(15%), the two last ones having never been described in ASCC. The main copy number alterations were gains of chromosome 3q (affecting
) and losses of chromosome 11q (affecting
. The combined analysis of somatic mutations and copy number alterations show that recurrent alterations of the PI3K/AKT/mTOR pathway are frequent (60%) in these tumours, as well as potentially targetable alterations of other signalling pathways that have never been described in ASCC such as chromatin remodelling (45%) and ubiquitin mediated proteolysis (35%). These results highlight the possible implication of these aberrant signalling pathways in anal carcinogenesis and suggest promising new therapeutic approaches in ASCC. The high somatic mutation burden found in some tumours, suggesting an elevated neoantigen load could also predict sensitivity of ASCC to immunotherapy.
HER2 breast cancer status determines patients’ eligibility for targeted therapy. HER2 level of amplification is associated with a better response to anti-HER2 therapy. Benefit of anti-HER2 therapy ...for equivocal cases remains debated.
We aimed to better characterize HER2-equivocal breast cancers by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) according to 2018 ASCO/CAP guidelines using PAM50 gene expression-based molecular subtyping and to investigate genome-wide copy number alterations of these cases. PAM50 (nCounter assay; Nanostring) was performed on RNA from FFPE samples of 60 HER2-equivocal cases. These cases were subsequently analyzed by Agilent 60-mer oligonucleotide microarrays for array-based comparative genomic hybridization (aCGH).
The 60 HER2-equivocal cases were classified as Luminal B in 31 cases (52%), HER2-Enriched in 14 cases (23%), Luminal A in 13 cases (22%) and Basal-like in 2 cases (3%) using PAM50. By IHC, 52 cases (87%) were ER+, 43 (72%) were also PgR+, 40 (67%) were grade III and 45 (75%) showed a high Ki67 > 20%. With aCGH, 23 cases (38%) presented chr 17q large copy number gain, 14 (23%) showed segmental copy number gain including HER2, 10 (17%) showed HER2 amplification, one (2%) showed a large copy number loss and 12 cases (20%) didn’t show any copy number alteration of the chr 17. Out of the 14 PAM50 HER2-Enriched cases, only 5 showed HER2 genomic amplification (Table). In total, 14 cases (23%) were discordant between molecular classification and genomic alteration status of the chr 17.Table260PTableGenomic alterations of chromosome 17Basal- likeHER2- EnrichedLuminal ALuminal BTotalHER2 amplified052310Large copy number gain0151723Segmental copy number gain254314No alteration032712Large copy number loss00011Total214133160
Using PAM50, the majority of HER2-equivocal cases were classified as Luminal tumors (Luminal B 52% and A 22%) and harbored mostly at the genomic level chr 17 segmental or large copy number gains. As there is no evidence of benefit of anti-HER2 therapy in these cases, it emphasizes the need of genomic status determination of HER2-equivocal cases.
Anne Vincent-Salomon.
Has not received any funding.
P. Morel: Full / Part-time employment: Nanostring. H.A. Brauer: Full / Part-time employment: Nanosting. A. Vincent-Salomon: Advisory / Consultancy, Consulting fees: Roche; Advisory / Consultancy, Consulting fees: AstraZeneca; Non-remunerated activity/ies, Contracted Research: Nanostring. All other authors have declared no conflicts of interest.
Liver adenomas are benign tumors at risk of malignant transformation. In a genome-wide search for loss of heterozygosity (LOH) associated with liver adenomas, we found a deletion in chromosome 12q in ...five of ten adenomas. In most cases, LOH at 12q was the only recurrent genetic alteration observed, suggesting the presence of a tumor-suppressor gene in that region. A minimal common region of deletion was defined in 12q24 that included the gene TCF1 (transcription factor 1), encoding hepatocyte nuclear factor 1 (HNF1; refs 1,2). Heterozygous germline mutations of TCF1 have been identified in individuals affected with maturity-onset diabetes of the young type 3 (MODY3; ref. 3). Bi-allelic inactivation of TCF1 was found in 10 of 16 screened adenomas, and heterozygous germline mutation were present in three affected individuals. Furthermore, 2 well-differentiated hepatocellular carcinomas (HCCs) occurring in normal liver contained somatic bi-allelic mutations of 30 screened HCCs. These results indicate that inactivation of TCF1, whether sporadic or associated with MODY3, is an important genetic event in the occurrence of human liver adenoma, and may be an early step in the development of some HCCs.
Maturity onset diabetes of the young type 3 (MODY3) is a consequence of heterozygous germline mutation in HNF1A. A subtype of hepatocellular adenoma (HCA) is also caused by biallelic somatic HNF1A ...mutations (H-HCA), and rare HCA may be related to MODY3. To better understand a relationship between the development of MODY3 and HCA, we compared both germline and somatic spectra of HNF1A mutations.
We compared 151 somatic HNF1A mutations in HCA with 364 germline mutations described in MODY3. We searched for genotoxic and oxidative stress features in HCA and surrounding liver tissue.
A spectrum of HNF1A somatic mutations significantly differed from the germline changes in MODY3. In HCA, we identified a specific hot spot at codon 206, nonsense and frameshift mutations mainly in the NH(2)-terminal part, and almost all amino acid substitutions were restricted to the POU-H domain. The high frequency of G-to-T tranversions, predominantly found on the nontranscribed DNA strand, suggested a genotoxic mechanism. However, no features of oxidative stress were observed in the nontumor liver tissue. Finally, in a few MODY3 patients with HNF1A germline mutation leading to amino acid substitutions outside the POU-H domain, we identified a different subtype of HCA either with a gp130 and/or CTNNB1 activating mutation.
Germline HNF1A mutations could be associated with different molecular subtypes of HCA. H-HCA showed mutations profoundly inactivating hepatocyte nuclear factor-1alpha function; they are associated with a genotoxic signature suggesting a specific toxicant exposure that could be associated with genetic predisposition.
Adaptive online data compression Jeannot, E.; Knutsson, B.; Bjorkman, M.
High Performance Distributed Computing: Proceedings of the 11th IEEE International Symposium on High Performance Distributed Computing; 24-26 July 2002,
2002
Conference Proceeding
Open access
Quickly transmitting large datasets in the context of distributed computing on wide area networks can be achieved by compressing data before transmission, However such an approach is not efficient ...when dealing with higher speed networks. Indeed, the time to compress a large file and to send it is greater than the time to send the uncompressed file. In this paper we explore and enhance an algorithm that allows us to overlap communications with compression and to automatically adapt the compression effort to currently available network and processor resources.
Grid-enabling medical image analysis Germain, C; Breton, V; Clarysse, P ...
Journal of clinical monitoring and computing
19, Issue:
4-5
Journal Article
Peer reviewed
Open access
Grids have emerged as a promising technology to handle the data and compute intensive requirements of many application areas. Digital medical image processing is a promising application area for ...grids. Given the volume of data, the sensitivity of medical information, and the joint complexity of medical datasets and computations expected in clinical practice, the challenge is to fill the gap between the grid middleware and the requirements of clinical applications. The research project AGIR (Grid Analysis of Radiological Data) presented in this paper addresses this challenge through a combined approach: on one hand, leveraging the grid middleware through core grid medical services which target the requirements of medical data processing applications; on the other hand, grid-enabling a panel of applications ranging from algorithmic research to clinical applications.