No abstract

Ovarian cancer represents the most common gynaecological malignancy and has the highest mortality of all female reproductive cancers. It has a rare predilection to develop brain metastases (BM). In this study, we evaluated the mutational profile of ovarian cancer metastases through Next-Generation Sequencing (NGS) with the aim of identifying potential clinically actionable genetic alterations with options for small molecule targeted therapy. Library preparation was conducted using Illumina TruSight Rapid Capture Kit in combination with a cancer specific enrichment kit covering 94 genes. BRCA-mutations were confirmed by using TruSeq Custom Amplicon Low Input Kit in combination with a custom-designed BRCA gene panel. In our cohort all eight sequenced BM samples exhibited a multitude of variant alterations, each with unique molecular profiles. The 37 identified variants were distributed over 22 cancer-related genes (23.4%). The number of mutated genes per sample ranged from 3 to 7 with a median of 4.5. The most commonly altered genes were BRCA1/2, TP53, and ATM. In total, 7 out of 8 samples revealed either a BRCA1 or a BRCA2 pathogenic mutation. Furthermore, all eight BM samples showed mutations in at least one DNA repair gene. Our NGS study of BM of ovarian carcinoma revealed a significant number of BRCA-mutations beside TP53, ATM and CHEK2 mutations. These findings strongly suggest the implication of BRCA and DNA repair malfunction in ovarian cancer metastasizing to the brain. Based on these findings, pharmacological PARP inhibition could be one potential targeted therapeutic for brain metastatic ovarian cancer patients.Electronic supplementary materialThe online version of this article (doi:10.1007/s11060-017-2459-z) contains supplementary material, which is available to authorized users.

Purpose: Chromosomal gains and losses resulting in altered gene dosage are known to be recurrent in gastrointestinal stromal tumors (GIST). The aim of our study was the identification of clinical relevant genes in these candidate regions.Material and Methods: A cohort of 174 GIST was investigated using DNA array (n ¼ 29), FISH (n ¼ 125), exome sequencing (n ¼ 13), and immunohistochemistry (n ¼ 145).Results: Array analysis revealed recurrent copy number variations (CNVs) of chromosomal arms 1p, 1q, 3p, 4q, 5q, 7p, 11q, 12p, 13q, 14q, 15q, and 22q. FISH studies of these CNVs showed that relative loss of 1p was associated with shorter disease-free survival (DFS). Analysis of exome sequencing concentrating on target regions showing recurrent CNVs revealed a median number of 3,404 (range 1,641-13,602) variants (SNPs, insertions, deletions) in each tumor minus paired blood sample; variants in at least three samples were observed in 37 genes. After further analysis, target genes were reduced to 10 in addition to KIT and PDGFRA. Immunohistochemical investigation showed that expression of SYNE2 and DIAPH1 was associated with shorter DFS, expression of RAD54L2 with shorter and expression of KIT with longer overall survival.Conclusion: Using a novel approach combining DNA arrays, exome sequencing, and immunohistochemistry, we were able to identify 10 target genes in GIST, of which three showed hithero unknown clinical relevance. Because the identified target genes SYNE2, MAPK8IP2, and DIAPH1 have been shown to be involved in MAP kinase signaling, our data further indicate the important role of this pathway in GIST.

Objective: In this retrospective study, we describe the clinical course, ultrasound findings and genetic investigations of fetuses affected by fetal akinesia. Materials and Methods: We enrolled 22 eukaryotic fetuses of 18 families, diagnosed with fetal akinesia between 2008 and 2016 at the Department of Obstetrics and Feto-Maternal Medicine at the Medical University of Vienna. Routine genetic evaluation included karyotyping and chromosomal microarray analysis. Retrospectively, exome sequencing was performed in the index case of 11 families, if stored DNA was available. Confirmation analyses and genetic diagnosis of siblings were performed by using Sanger sequencing. Results: Whole exome sequencing identified pathogenic variants of CNTN1, RYR1, NEB, GLDN, HRAS and TNNT3 in six cases of 11 families. In three of these families, the variants were confirmed in the respective sibling. Conclusions: The present study demonstrates a high diagnostic yield of exome sequencing in fetuses affected by akinesia syndrome, especially if family history is positive. Still, in a large part the underlying genetic cause remained unknown, whereas precise clinical evaluation in combination with exome sequencing shows to be the best tool to find the disease causing variants.