27 research outputs found
Pan-cancer analysis of whole genomes
Cancer is driven by genetic change, and the advent of massively parallel sequencing has enabled systematic documentation of this variation at the whole-genome scale(1-3). Here we report the integrative analysis of 2,658 whole-cancer genomes and their matching normal tissues across 38 tumour types from the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium of the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA). We describe the generation of the PCAWG resource, facilitated by international data sharing using compute clouds. On average, cancer genomes contained 4-5 driver mutations when combining coding and non-coding genomic elements; however, in around 5% of cases no drivers were identified, suggesting that cancer driver discovery is not yet complete. Chromothripsis, in which many clustered structural variants arise in a single catastrophic event, is frequently an early event in tumour evolution; in acral melanoma, for example, these events precede most somatic point mutations and affect several cancer-associated genes simultaneously. Cancers with abnormal telomere maintenance often originate from tissues with low replicative activity and show several mechanisms of preventing telomere attrition to critical levels. Common and rare germline variants affect patterns of somatic mutation, including point mutations, structural variants and somatic retrotransposition. A collection of papers from the PCAWG Consortium describes non-coding mutations that drive cancer beyond those in the TERT promoter(4); identifies new signatures of mutational processes that cause base substitutions, small insertions and deletions and structural variation(5,6); analyses timings and patterns of tumour evolution(7); describes the diverse transcriptional consequences of somatic mutation on splicing, expression levels, fusion genes and promoter activity(8,9); and evaluates a range of more-specialized features of cancer genomes(8,10-18).Peer reviewe
Radiations and male fertility
During recent years, an increasing percentage of male infertility has to be attributed to an array of environmental,
health and lifestyle factors. Male infertility is likely to be affected by the intense exposure to heat and extreme
exposure to pesticides, radiations, radioactivity and other hazardous substances. We are surrounded by several types
of ionizing and non-ionizing radiations and both have recognized causative effects on spermatogenesis. Since it is
impossible to cover all types of radiation sources and their biological effects under a single title, this review is
focusing on radiation deriving from cell phones, laptops, Wi-Fi and microwave ovens, as these are the most
common sources of non-ionizing radiations, which may contribute to the cause of infertility by exploring the effect
of exposure to radiofrequency radiations on the male fertility pattern. From currently available studies it is clear that
radiofrequency electromagnetic fields (RF-EMF) have deleterious effects on sperm parameters (like sperm count,
morphology, motility), affects the role of kinases in cellular metabolism and the endocrine system, and produces
genotoxicity, genomic instability and oxidative stress. This is followed with protective measures for these radiations
and future recommendations. The study concludes that the RF-EMF may induce oxidative stress with an increased
level of reactive oxygen species, which may lead to infertility. This has been concluded based on available
evidences from in vitro and in vivo studies suggesting that RF-EMF exposure negatively affects sperm quality