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Whole-genome sequencing of 25 metastatic melanomas and matched germline DNA in humans reveals that the highest mutation load is associated with chronic sun exposure, and that the PREX2 gene is mutated in approximately 14 per cent of cases

Chromosomes within micronuclei are shown to be damaged during S phase and become highly fragmented, and the damaged pieces can be reincorporated into the genome.

Here it is shown that telomere dysfunction drives metabolic and mitochondrial compromise. Mice with dysfunctional telomeres activate p53, which in turn represses PGC-1α and PGC-1β, master regulators of metabolic and mitochondrial processes. This results in reduced mitochondrial mass, mitochondrial dysfunction and reduced ATP generation, impaired gluconeogenesis, cariomyopathy and increased reactive oxygen species. This telomere–p53–PGC pathway shows how telomere dysfunction may compromise organ function and contribute to age-related disorders.

A genome-wide screen has identified a frequent region of amplification on chromosome 5p13 in a number of cancer types. Functional studies now identify a protein localized to the Golgi apparatus, GOLPH3, as a novel oncogene affected by this amplification which can transform cells in vitro and lead to tumour formation in vivo. GOLPH3 overexpression activates the mTOR signalling pathway and renders cancer cells sensitive to the drug rapamycin.

A mouse lymphoma model that shows a similar level of genomic instability generally seen in human cancer has been created. In a comparative genomics approach, recurrent genetic alterations found in this model are used as a filter to identify overlapping alterations in human T-cell acute lymphoblastic lymphomas, including in the FBXW7 and NOTCH genes.

Analysis of glioblastoma samples and derived neurospheres and xenografts shows that chromosomal and extrachromosomal alterations often display divergent inheritance patterns during cell culture and xenografting.

Deficiency in dystrophin leads to death with cardiorespiratory failure in humans, but mice lacking dystrophin have minimal heart defects. Blau and colleagues find that mice that lack dystrophin and have shorter telomeres exhibit cardiac defects similar to human patients, with an increase in oxidative stress. The authors also found that onset of cardiac defects could be delayed by antioxidant treatments and that, strikingly, patients also have shortened telomeres.

The Cancer Genome Atlas reports on molecular evaluation of 295 primary gastric adenocarcinomas and proposes a new classification of gastric cancers into 4 subtypes, which should help with clinical assessment and trials of targeted therapies.

The Cancer Genome Atlas Research Network report integrated genomic and molecular analyses of 164 squamous cell carcinomas and adenocarcinomas of the oesophagus; they find genomic and molecular features that differentiate squamous and adenocarcinomas of the oesophagus, and strong similarities between oesophageal adenocarcinomas and the chromosomally unstable variant of gastric adenocarcinoma, suggesting that gastroesophageal adenocarcinoma is a single disease entity.

The Cancer Genome Atlas presents an integrative genome-wide analysis of genetic alterations in 279 head and neck squamous cell carcinomas (HNSCCs), which are classified by human papillomavirus (HPV) status; alterations in EGFR, FGFR, PIK3CA and cyclin-dependent kinases are shown to represent candidate targets for therapeutic intervention in most HNSCCs.

This paper reports integrative molecular analyses of urothelial bladder carcinoma at the DNA, RNA, and protein levels performed as part of The Cancer Genome Atlas project; recurrent mutations were found in 32 genes, including those involved in cell-cycle regulation, chromatin regulation and kinase signalling pathways; chromatin regulatory genes were more frequently mutated in urothelial carcinoma than in any other common cancer studied so far.

An integrative genomic analysis of several hundred endometrial carcinomas shows that a minority of tumour samples carry copy number alterations or TP53 mutations and many contain key cancer-related gene mutations, such as those involved in canonical pathways and chromatin remodelling; a reclassification of endometrial tumours into four distinct types is proposed, which may have an effect on patient treatment regimes.

This paper describes molecular subtypes of cervical cancers, including squamous cell carcinoma and adenocarcinoma clusters defined by HPV status and molecular features, and distinct molecular pathways that are activated in cervical carcinomas caused by different somatic alterations and HPV types.

An integrated transcriptome, genome, methylome and proteome analysis of over 200 lung adenocarcinomas reveals high rates of somatic mutations, 18 statistically significantly mutated genes including RIT1 and MGA, splicing changes, and alterations in MAPK and PI(3)K pathway activity.

Peter Campbell and colleagues identify PLCG1 and PTPRB as new driver genes for angiosarcoma through whole-exome sequencing of tumor samples. They find somatic PTPRB mutations in 10 of 39 cases and PLCG1 mutations in 3 of 34 cases, along with mutations in known cancer-related genes.

Here it is shown that reactivation of endogenous telomerase activity in mice extends telomeres, reduces DNA damage signalling, allows resumption of proliferation in quiescent cultures, and eliminates degenerative phenotypes across multiple organs including testes, spleens and intestines. Accumulating evidence implicating telomere damage as a driver of age-associated organ decline and disease and the reversal of damage observed here support the development of regenerative strategies designed to restore telomere integrity.

The Cancer Genome Atlas consortium reports on their genome-wide characterization of somatic alterations in colorectal cancer; in addition to revealing a remarkably consistent pattern of genomic alteration, with 24 genes being significantly mutated, the study identifies new targets for therapeutic intervention and suggests an important role for MYC-directed transcriptional activation and repression.

Comprehensive analyses of 178 lung squamous cell carcinomas by The Cancer Genome Atlas project show that the tumour type is characterized by complex genomic alterations, with statistically recurrent mutations in 11 genes, including TP53 in nearly all samples; a potential therapeutic target is identified in most of the samples studied.

With a comprehensive analysis of sequencing data, DNA copy number, gene expression and DNA methylation in a large number of human glioblastomas, The Cancer Genome Atlas project initiative provides a broad overview of the genes and pathways that are altered in this cancer type.

Haematopoietic stem and progenitor cells (HSPCs) are found in unique bone marrow microenvironments. Silberstein and colleagues use imaging cytometry to quantitatively determine HSPC distribution in femoral bones. They find that HSPCs are in endosteal zones, in close proximity to specialized microvessels, and that they appear in a hypoxic state whether or not they are close to the vasculature.

Current clinical practice is organized according to tissue or organ of origin of tumors. Now, The Cancer Genome Atlas (TCGA) Research Network has started to identify genomic and other molecular commonalities among a dozen different types of cancer. Emerging similarities and contrasts will form the basis for targeted therapies of the future and for repurposing existing therapies by molecular rather than histological similarities of the diseases.