Explore the vast range of titles available.

Matthew Meyerson, Ramaswamy Govindan and colleagues examine the exome sequences and copy number profiles of 660 lung adenocarcinoma and 484 lung squamous cell carcinoma tumors. They identify novel significantly mutated genes and amplification peaks and find that around half of the tumors have at least five predicted neoepitopes. To compare lung adenocarcinoma (ADC) and lung squamous cell carcinoma (SqCC) and to identify new drivers of lung carcinogenesis, we examined the exome sequences and copy number profiles of 660 lung ADC and 484 lung SqCC tumor–normal pairs. Recurrent alterations in lung SqCCs were more similar to those of other squamous carcinomas than to alterations in lung ADCs. New significantly mutated genes included PPP3CA , DOT1L , and FTSJD1 in lung ADC, RASA1 in lung SqCC, and KLF5 , EP300 , and CREBBP in both tumor types. New amplification peaks encompassed MIR21 in lung ADC, MIR205 in lung SqCC, and MAPK1 in both. Lung ADCs lacking receptor tyrosine kinase–Ras–Raf pathway alterations had mutations in SOS1 , VAV1 , RASA1 , and ARHGAP35 . Regarding neoantigens, 47% of the lung ADC and 53% of the lung SqCC tumors had at least five predicted neoepitopes. Although targeted therapies for lung ADC and SqCC are largely distinct, immunotherapies may aid in treatment for both subtypes.

Using whole-genome and whole-exome sequencing, this study identifies eight significantly mutated genes in oesophageal squamous cell cancer, including two genes, ADAM29 and FAM135B , not previously associated with this cancer type. The genomic landscape of oesophageal cancer This paper reports the genomic analysis of samples from more than a hundred cases of oesophageal squamous cell carcinoma. Eight significantly mutated genes were identified, six of them well known as tumour-associated genes and two — ADAM29 and FAM135B — not previously described in this type of cancer. Analyses reveal frequent mutations in several important histone regulator genes and identify a microRNA encoded in the amplified 11q13.3-13.4 region as a novel oncogene. Furthermore, genetically, oesophageal cancer is shown to share common pathogenic mechanisms with head and neck squamous cell carcinoma. Oesophageal cancer is one of the most aggressive cancers and is the sixth leading cause of cancer death worldwide 1 . Approximately 70% of global oesophageal cancer cases occur in China, with oesophageal squamous cell carcinoma (ESCC) being the histopathological form in the vast majority of cases (>90%) 2 , 3 . Currently, there are limited clinical approaches for the early diagnosis and treatment of ESCC, resulting in a 10% five-year survival rate for patients. However, the full repertoire of genomic events leading to the pathogenesis of ESCC remains unclear. Here we describe a comprehensive genomic analysis of 158 ESCC cases, as part of the International Cancer Genome Consortium research project. We conducted whole-genome sequencing in 17 ESCC cases and whole-exome sequencing in 71 cases, of which 53 cases, plus an additional 70 ESCC cases not used in the whole-genome and whole-exome sequencing, were subjected to array comparative genomic hybridization analysis. We identified eight significantly mutated genes, of which six are well known tumour-associated genes ( TP53 , RB1 , CDKN2A , PIK3CA , NOTCH1 , NFE2L2 ), and two have not previously been described in ESCC ( ADAM29 and FAM135B ). Notably, FAM135B is identified as a novel cancer-implicated gene as assayed for its ability to promote malignancy of ESCC cells. Additionally, MIR548K , a microRNA encoded in the amplified 11q13.3-13.4 region, is characterized as a novel oncogene, and functional assays demonstrate that MIR548K enhances malignant phenotypes of ESCC cells. Moreover, we have found that several important histone regulator genes ( MLL2 (also called KMT2D ), ASH1L , MLL3 ( KMT2C ), SETD1B , CREBBP and EP300 ) are frequently altered in ESCC. Pathway assessment reveals that somatic aberrations are mainly involved in the Wnt, cell cycle and Notch pathways. Genomic analyses suggest that ESCC and head and neck squamous cell carcinoma share some common pathogenic mechanisms, and ESCC development is associated with alcohol drinking. This study has explored novel biological markers and tumorigenic pathways that would greatly improve therapeutic strategies for ESCC.

Zhiming Cai and colleagues report the exome sequencing of tumor and matched normal tissue from nine transitional cell carcinomas (TCCs) of the bladder, with further screening in 88 additional subjects. The authors identify mutations in chromatin remodeling genes in 59% of the 97 TCC subjects. Transitional cell carcinoma (TCC) is the most common type of bladder cancer. Here we sequenced the exomes of nine individuals with TCC and screened all the somatically mutated genes in a prevalence set of 88 additional individuals with TCC with different tumor stages and grades. In our study, we discovered a variety of genes previously unknown to be mutated in TCC. Notably, we identified genetic aberrations of the chromatin remodeling genes ( UTX, MLL - MLL3 , CREBBP - EP300 , NCOR1 , ARID1A and CHD6 ) in 59% of our 97 subjects with TCC. Of these genes, we showed UTX to be altered substantially more frequently in tumors of low stages and grades, highlighting its potential role in the classification and diagnosis of bladder cancer. Our results provide an overview of the genetic basis of TCC and suggest that aberration of chromatin regulation might be a hallmark of bladder cancer.

Insects are biotechnologically important producers of recombinant proteins and materials, and their biology as crop pests has substantial economic consequences. Xiang et al . map cytosine methylation genome-wide at single-base resolution in the silkworm, opening the door for global studies of epigenetic DNA modification in insects. Epigenetic regulation in insects may have effects on diverse biological processes. Here we survey the methylome of a model insect, the silkworm Bombyx mori , at single-base resolution using Illumina high-throughput bisulfite sequencing (MethylC-Seq). We conservatively estimate that 0.11% of genomic cytosines are methylcytosines, all of which probably occur in CG dinucleotides. CG methylation is substantially enriched in gene bodies and is positively correlated with gene expression levels, suggesting it has a positive role in gene transcription. We find that transposable elements, promoters and ribosomal DNAs are hypomethylated, but in contrast, genomic loci matching small RNAs in gene bodies are densely methylated. This work contributes to our understanding of epigenetics in insects, and in contrast to previous studies of the highly methylated genomes of Arabidopsis 1 and human 2 , demonstrates a strategy for sequencing the epigenomes of organisms such as insects that have low levels of methylation.

Huanming Yang, Zhiming Cai, Jun Wang and colleagues report whole-exome sequencing of 10 clear cell renal cell carcinomas followed by a screen of ~1,100 genes in a total of 98 tumors. They found 12 new disease-associated genes and detected frequent alterations in the ubiquitin-mediated proteolysis pathway. We sequenced whole exomes of ten clear cell renal cell carcinomas (ccRCCs) and performed a screen of ∼1,100 genes in 88 additional ccRCCs, from which we discovered 12 previously unidentified genes mutated at elevated frequencies in ccRCC. Notably, we detected frequent mutations in the ubiquitin-mediated proteolysis pathway (UMPP), and alterations in the UMPP were significantly associated with overexpression of HIF1α and HIF2α in the tumors ( P = 0.01 and 0.04, respectively). Our findings highlight the potential contribution of UMPP to ccRCC tumorigenesis through the activation of the hypoxia regulatory network.

Interrogation of cell-free DNA (cfDNA) represents an emerging approach to non-invasively estimate disease burden in multiple myeloma (MM). Here, we examined low-pass whole genome sequencing (LPWGS) of cfDNA for its predictive value in relapsed/ refractory MM (RRMM). We observed that cfDNA positivity, defined as ≥10% tumor fraction by LPWGS, was associated with significantly shorter progression-free survival (PFS) in an exploratory test cohort of 16 patients who were actively treated on diverse regimens. We prospectively determined the predictive value of cfDNA in 86 samples from 45 RRMM patients treated with elotuzumab, pomalidomide, bortezomib, and dexamethasone in a phase II clinical trial (NCT02718833). PFS in patients with tumor-positive and -negative cfDNA after two cycles of treatment was 1.6 and 17.6 months, respectively (HR 7.6, P < 0.0001). Multivariate hazard modelling confirmed cfDNA as independent risk factor (HR 96.6, P = 6.92e-05). While correlating with serum-free light chains and bone marrow, cfDNA additionally discriminated patients with poor PFS among those with the same response by IMWG criteria. In summary, detectability of MM-derived cfDNA, as a measure of substantial tumor burden with therapy, independently predicts poor PFS and may provide refinement for standard-of-care response parameters to identify patients with poor response to treatment earlier than is currently feasible.

The bone marrow (BM) is not only a reservoir of hematopoietic stem cells but a repository of immunological memory cells. Further characterizing BM-resident memory T cells would be helpful to reveal the complicated relationship between the BM and immunological memory. In this study, we identified CD122high stem cell antigen-1 (Sca-1) high B cell lymphoma 2 (Bcl-2) high CD4+ stem cell-like memory T cells (TSCMs) as a distinct memory T cell subset, which preferentially reside in the BM, where they respond vigorously to blood-borne antigens. Interestingly, the natural CD4+ TSCMs homing to the BM colocalized with VCAM-1+ IL-15+ IL-7+ CXCL-12+ stromal cells. Furthermore, compared to spleen-resident CD4+ TSCMs, BM-resident TSCMs induced the production of high-affinity antibodies against influenza by B lymphocytes more efficiently. Taken together, these observations indicate that the BM provides an appropriate microenvironment for the survival of CD4+ TSCMs, which broadens our knowledge regarding the memory maintenance of antigen-specific CD4+ T lymphocytes.

Next-generation sequencing-based Digital Gene Expression tag profiling (DGE) has been used to study the changes in gene expression profiling. To compare the quality of the data generated by microarray and DGE, we examined the gene expression profiles of an in vitro cell model with these platforms. In this study, 17,362 and 15,938 genes were detected by microarray and DGE, respectively, with 13,221 overlapping genes. The correlation coefficients between the technical replicates were >0.99 and the detection variance was <9% for both platforms. The dynamic range of microarray was fixed with four orders of magnitude, whereas that of DGE was extendable. The consistency of the two platforms was high, especially for those abundant genes. It was more difficult for the microarray to distinguish the expression variation of less abundant genes. Although microarrays might be eventually replaced by DGE or transcriptome sequencing (RNA-seq) in the near future, microarrays are still stable, practical, and feasible, which may be useful for most biological researchers.

Zhiming Cai and colleagues report whole-genome and whole-exome sequencing of 99 paired tumor-normal samples of transitional cell carcinoma of the bladder. They find that 32% of tumors harbor alterations in genes involved in sister chromatid cohesion, including STAG2 , ESPL1 , NIPBL , SMC1A and SMC3 . Bladder cancer is one of the most common cancers worldwide, with transitional cell carcinoma (TCC) being the predominant form. Here we report a genomic analysis of TCC by both whole-genome and whole-exome sequencing of 99 individuals with TCC. Beyond confirming recurrent mutations in genes previously identified as being mutated in TCC, we identified additional altered genes and pathways that were implicated in TCC. Notably, we discovered frequent alterations in STAG2 and ESPL1 , two genes involved in the sister chromatid cohesion and segregation (SCCS) process. Furthermore, we also detected a recurrent fusion involving FGFR3 and TACC3 , another component of SCCS, by transcriptome sequencing of 42 DNA-sequenced tumors. Overall, 32 of the 99 tumors (32%) harbored genetic alterations in the SCCS process. Our analysis provides evidence that genetic alterations affecting the SCCS process may be involved in bladder tumorigenesis and identifies a new therapeutic possibility for bladder cancer.