Multigene testing of moderate-risk genes: be mindful of the missense.

BACKGROUND: Moderate-risk genes have not been extensively studied, and missense substitutions in them are generally returned to patients as variants of uncertain significance lacking clearly defined risk estimates. The fraction of early-onset breast cancer cases carrying moderate-risk genotypes and quantitative methods for flagging variants for further analysis have not been established. METHODS: We evaluated rare missense substitutions identified from a mutation screen of ATM, CHEK2, MRE11A, RAD50, NBN, RAD51, RINT1, XRCC2 and BARD1 in 1297 cases of early-onset breast cancer and 1121 controls via scores from Align-Grantham Variation Grantham Deviation (GVGD), combined annotation dependent depletion (CADD), multivariate analysis of protein polymorphism (MAPP) and PolyPhen-2. We also evaluated subjects by polygenotype from 18 breast cancer risk SNPs. From these analyses, we estimated the fraction of cases and controls that reach a breast cancer OR≥2.5 threshold. RESULTS: Analysis of mutation screening data from the nine genes revealed that 7.5% of cases and 2.4% of controls were carriers of at least one rare variant with an average OR≥2.5. 2.1% of cases and 1.2% of controls had a polygenotype with an average OR≥2.5. CONCLUSIONS: Among early-onset breast cancer cases, 9.6% had a genotype associated with an increased risk sufficient to affect clinical management recommendations. Over two-thirds of variants conferring this level of risk were rare missense substitutions in moderate-risk genes. Placement in the estimated OR≥2.5 group by at least two of these missense analysis programs should be used to prioritise variants for further study. Panel testing often creates more heat than light; quantitative approaches to variant prioritisation and classification may facilitate more efficient clinical classification of variants.

Rare mutations in XRCC2 increase the risk of breast cancer.

An exome-sequencing study of families with multiple breast-cancer-affected individuals identified two families with XRCC2 mutations, one with a protein-truncating mutation and one with a probably deleterious missense mutation. We performed a population-based case-control mutation-screening study that identified six probably pathogenic coding variants in 1,308 cases with early-onset breast cancer and no variants in 1,120 controls (the severity grading was p < 0.02). We also performed additional mutation screening in 689 multiple-case families. We identified ten breast-cancer-affected families with protein-truncating or probably deleterious rare missense variants in XRCC2. Our identification of XRCC2 as a breast cancer susceptibility gene thus increases the proportion of breast cancers that are associated with homologous recombination-DNA-repair dysfunction and Fanconi anemia and could therefore benefit from specific targeted treatments such as PARP (poly ADP ribose polymerase) inhibitors. This study demonstrates the power of massively parallel sequencing for discovering susceptibility genes for common, complex diseases.

A sample storage management system for biobanks.

SUMMARY: Establishment of large-scale biobanks of human specimens is essential to conduct molecular pathological or epidemiological studies. This requires automation of procedures for specimen cataloguing and tracking through complex analytical processes. The International Agency for Research on Cancer (IARC) develops a large portfolio of studies broadly aimed at cancer prevention and including cohort, case-control and case-only studies in various parts of the world. This diversity of study designs, structure, annotations and specimen collections is extremely difficult to accommodate into a single sample management system (SMS). Current commercial or academic SMS are often restricted to a few sample types and tailored to a limited number of analytic workflows [Voegele et al. (2007) A laboratory information management system (LIMS) for a high throughput genetic platform aimed at candidate gene mutation screening. Bioinformatics, 23, 2504-2506]. Thus, we developed a system based on a three-tier architecture and relying on an Oracle database and an Oracle Forms web application. Data are imported through forms or csv files, and information retrieval is enabled via multi-criteria queries that can generate different types of reports including tables, Excel files, trees, pictures and graphs. The system is easy to install, flexible, expandable and implemented with a high degree of data security and confidentiality. Both the database and the interface have been modeled to be compatible with and adaptable to almost all types of biobanks. AVAILABILITY AND IMPLEMENTATION: The SMS source codes, which are under the GNU General Public License, and supplementary data are freely available at 'http://www-gcs.iarc.fr/sms.php' SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Integrative and comparative genomic analyses identify clinically relevant pulmonary carcinoid groups and unveil the supra-carcinoids.

The worldwide incidence of pulmonary carcinoids is increasing, but little is known about their molecular characteristics. Through machine learning and multi-omics factor analysis, we compare and contrast the genomic profiles of 116 pulmonary carcinoids (including 35 atypical), 75 large-cell neuroendocrine carcinomas (LCNEC), and 66 small-cell lung cancers. Here we report that the integrative analyses on 257 lung neuroendocrine neoplasms stratify atypical carcinoids into two prognostic groups with a 10-year overall survival of 88% and 27%, respectively. We identify therapeutically relevant molecular groups of pulmonary carcinoids, suggesting DLL3 and the immune system as candidate therapeutic targets; we confirm the value of OTP expression levels for the prognosis and diagnosis of these diseases, and we unveil the group of supra-carcinoids. This group comprises samples with carcinoid-like morphology yet the molecular and clinical features of the deadly LCNEC, further supporting the previously proposed molecular link between the low- and high-grade lung neuroendocrine neoplasms.

A Laboratory Information Management System (LIMS) for a high throughput genetic platform aimed at candidate gene mutation screening.

UNLABELLED: High throughput mutation screening in an automated environment generates large data sets that have to be organized and stored reliably. Complex multistep workflows require strict process management and careful data tracking. We have developed a Laboratory Information Management Systems (LIMS) tailored to high throughput candidate gene mutation scanning and resequencing that respects these requirements. Designed with a client/server architecture, our system is platform independent and based on open-source tools from the database to the web application development strategy. Flexible, expandable and secure, the LIMS, by communicating with most of the laboratory instruments and robots, tracks samples and laboratory information, capturing data at every step of our automated mutation screening workflow. An important feature of our LIMS is that it enables tracking of information through a laboratory workflow where the process at one step is contingent on results from a previous step. AVAILABILITY: Script for MySQL database table creation and source code of the whole JSP application are freely available on our website: http://www-gcs.iarc.fr/lims/. SUPPLEMENTARY INFORMATION: System server configuration, database structure and additional details on the LIMS and the mutation screening workflow are available on our website: http://www-gcs.iarc.fr/lims/

TLR9 re-expression in cancer cells extends the S-phase and stabilizes p16(INK4a) protein expression.

Toll-like receptor 9 (TLR9) recognizes bacterial, viral or cell damage-associated DNA, which initiates innate immune responses. We have previously shown that TLR9 expression is downregulated in several viral induced cancers including HPV16-induced cervical neoplasia. Findings supported that downregulation of TLR9 expression is involved in loss of anti-viral innate immunity allowing an efficient viral replication. Here we investigated the role of TLR9 in altering the growth of transformed epithelial cells. Re-introducing TLR9 under the control of an exogenous promoter in cervical or head and neck cancer patient-derived cells reduced cell proliferation, colony formation and prevented independent growth of cells under soft agar. Neither TLR3, 7, nor the TLR adapter protein MyD88 expression had any effect on cell proliferation, indicating that TLR9 has a unique role in controlling cell growth. The reduction of cell growth was not due to apoptosis or necrosis, yet we observed that cells expressing TLR9 were slower in entering the S-phase of the cell cycle. Microarray-based gene expression profiling analysis highlighted a strong interferon (IFN) signature in TLR9-expressing head and neck cancer cells, with an increase in IFN-type I and IL-29 expression (IFN-type III), yet neither IFN-type I nor IL-29 production was responsible for the block in cell growth. We observed that the protein half-life of p16(INK4a) was increased in TLR9-expressing cells. Taken together, these data show for the first time that TLR9 affects the cell cycle by regulating p16(INK4a) post-translational modifications and highlights the role of TLR9 in the events that lead to carcinogenesis.

TP53, EGFR, and KRAS mutations in relation to VHL inactivation and lifestyle risk factors in renal-cell carcinoma from central and eastern Europe.

Renal-cell carcinomas (RCC) are frequent in central and eastern Europe and the reasons remain unclear. Molecular mechanisms, except for VHL, have not been much investigated. We analysed 361 RCCs (334 clear-cell carcinomas) from a multi-centre case-control study for mutations in TP53 (exons 5-9 in the whole series and exons 4 and 10 in a pilot subset of 60 tumours) and a pilot 50 tumours for mutations in EGFR (exons 18-21) or KRAS (codon 12) in relation to VHL status. TP53 mutations were detected in 4% of clear-cell cases, independently of VHL mutations. In non-clear-cell carcinomas, they were detected in 11% of VHL-wild-type tumours and in 0% of tumours with VHL functional mutations. No mutations were found in EGFR or KRAS. We conclude that mutations in TP53, KRAS, or EGFR are not major contributors to the RCC development even in the absence of VHL inactivation. The prevalence of TP53 mutations in relation to VHL status may differ between clear-cell and other renal carcinomas.