Project description:High throughput RNA sequencing has revealed pervasive transcription of human genome than previously anticipated. However, the extent of natural antisense transcripts (NATs) expression, their regulation of cognate sense genes, and the role of NATs in cancer remain poorly understood. Here, we use strand-specific paired-end RNA sequencing (ssRNASeq) data from 376 cancer patients covering 9 tissue types to comprehensively characterize the landscape of antisense expression. We found consistent antisense expression in at least 38% of annotated transcripts, which in general is positively correlated with sense gene expression. Investigations of sense/antisense pair expression across tissue types revealed lineage-specific, ubiquitous and cancer-specific antisense loci transcription. Comparisons between tumor and normal samples identified both concordant (same direction) and discordant (opposite direction) sense/antisense expression patterns. Finally, we provide oncoNAT, a catalog of cancer related genes with significant antisense transcription, which will enable future investigations of sense/antisense regulation in cancer. Using oncoNAT we identified several functional NATs, including NKX2-1-AS that regulates the NKX2-1 oncogene and cell proliferation in lung cancer cells. Overall, this study provides a comprehensive account of NATs and supports a role for NATs regulation of tumor suppressors and oncogenes in cancer biology. Strand-specific RNA sequencing data (ssRNASeq) of cancer and benign samples. SRP048484 (PRJNA262128).
Project description:High throughput RNA sequencing has revealed pervasive transcription of human genome than previously anticipated. However, the extent of natural antisense transcripts (NATs) expression, their regulation of cognate sense genes, and the role of NATs in cancer remain poorly understood. Here, we use strand-specific paired-end RNA sequencing (ssRNASeq) data from 376 cancer patients covering 9 tissue types to comprehensively characterize the landscape of antisense expression. We found consistent antisense expression in at least 38% of annotated transcripts, which in general is positively correlated with sense gene expression. Investigations of sense/antisense pair expression across tissue types revealed lineage-specific, ubiquitous and cancer-specific antisense loci transcription. Comparisons between tumor and normal samples identified both concordant (same direction) and discordant (opposite direction) sense/antisense expression patterns. Finally, we provide oncoNAT, a catalog of cancer related genes with significant antisense transcription, which will enable future investigations of sense/antisense regulation in cancer. Using oncoNAT we identified several functional NATs, including NKX2-1-AS that regulates the NKX2-1 oncogene and cell proliferation in lung cancer cells. Overall, this study provides a comprehensive account of NATs and supports a role for NATs regulation of tumor suppressors and oncogenes in cancer biology. Strand-specific RNA sequencing data (ssRNASeq) of cancer and benign samples. SRP050021 (PRJNA267614). Processed data files linked to SuperSeries record.
Project description:Despite abundant evidence demonstrating that platelets foster metastasis, anti- platelet agents have low therapeutic potential due to the risk of hemorrhages. In addition, whether platelets can regulate metastasis at the late stages of the disease remains unknown. In this study, we subjected syngeneic models of metastasis to various thrombocytopenic regimes to show that platelets provide a biphasic contribution to metastasis. While potent intravascular binding of platelets to tumor cells efficiently promotes metastasis, platelets further support the outgrowth of established metastases via immune suppression. Genetic depletion and pharmacological targeting of the platelet-specific receptor GPVI in humanized mouse models efficiently reduced the growth of established metastases, independently of active platelet binding to tumor cells in the bloodstream. Our study is the first to demonstrate therapeutic efficacy when targeting animals bearing growing metastases. It further identifies GPVI as the first molecular target whose inhibition can impair metastasis without inducing collateral hemostatic perturbations.
Project description:MicroRNAs have been implicated in various skin cancers, including melanoma, squamous cell carcinoma, and basal cell carcinoma; however, the expression of microRNAs and their role in Merkel cell carcinoma (MCC) have yet to be explored in depth. To identify microRNAs specific to MCC (MCC-miRs), next-generation sequencing (NGS) of small RNA libraries was performed on different tissue samples including MCCs, other cutaneous tumors, and normal skin. Comparison of the profiles identified several microRNAs upregulated and downregulated in MCC. For validation, their expression was measured via qRT-PCR in a larger group of MCC and in a comparison group of non-MCC cutaneous tumors and normal skin. Eight microRNAs were upregulated in MCC: miR-502-3p, miR-9, miR-7, miR-340, miR-182, miR-190b, miR-873, and miR-183. Three microRNAs were downregulated: miR-3170, miR-125b, and miR-374c. Many of these MCC-miRs, with the miR-183/182/96a cistron in particular, have connections to tumorigenic pathways implicated in MCC pathogenesis. In situ hybridization confirmed that the highly expressed MCC-miR, miR-182, is localized within tumor cells. Furthermore, NGS and qRT-PCR reveals that several of these MCC-miRs are highly expressed in the patient-derived MCC cell line, MS-1. These data indicate that we have identified a set of MCC-miRs with high implications for MCC research. To identify microRNAs specific to Merkel cell carcinoma (MCC) next-generation sequencing (NGS) of small RNA libraries was performed on different tissue samples including MCCs, other cutaneous tumors, and normal skin
Project description:Emerging evidences suggest that both function and position of organelles are pivotal for tumor cell dissemination. Among them, lysosomes stand out as they integrate metabolic sensing with gene regulation and secretion of proteases. Yet, how lysosomes function is linked to their position and thereby control metastatic progression remains elusive. Here, we analyzed lysosome subcellular distribution in micropatterned patient-derived melanoma cells and found that lysosome spreading scales with their aggressiveness. Peripheral lysosomes promote invadopodia-based matrix degradation and invasion of melanoma cells which is directly linked to their lysosomal and cell transcriptional programs. When controlling lysosomal positioning using chemo-genetical heterodimerization in melanoma cells, we demonstrated that perinuclear clustering impairs lysosomal secretion, matrix degradation and invasion. Impairing lysosomal spreading in a zebrafish metastasis model significantly reduces invasive outgrowth. Our study provides a mechanistic demonstration that lysosomal positioning controls cell invasion, illustrating the importance of organelle adaptation in carcinogenesis.
Project description:Tryptic peptides and N-glycans were spatially mapped and visualised on formalin-fixed paraffin-embedded (FFPE) endometrial cancer tissue microarrays (TMAs) using an ultrafleXtreme MALDI-ToF/ToF MS instrument (Bruker Daltonics). FFPE egg white was placed either side of each TMA and used as an external control to monitor detector performance and sample preparation.
Project description:Nascent allohexaploid wheat may represent the initial genetic state for the evolution and domestication of common wheat, which arose by combining the AB genomes of tetraploid Triticum turgidum with the D genome from Aegilops tauschii and out-competed its parents in growth vigor and adaptability. To better understand the molecular basis for this success, we performed mRNA and small RNA expression analyses in three tissues of nascent allohexaploid wheat and its following generations, their progenitors, and Chinese Spring, with the assistance of newly released A and D genome sequences. We found that nonadditive expression was rare among protein-coding genes which exhibited profound parental expression level dominance, with genes of total homoeolog expression level in nascent allohexaploid progeny similar to their expression levels in T. turgidum functionally enriched for development and those to Ae. tauschii distinctively for adaptation. In contrast, miRNAs appeared to be sensitive to polyploidization, with nonadditively expressed miRNAs potentially involved in growth vigor and adaptation. Meanwhile, siRNAs may contribute to biased repression of D homoeolog, possibly due to increased siRNA density on transposable element (TE)-associated D homoeologs. Together, our data provide new insights into homoeolog regulatory mechanisms that may be essential to heterosis in nascent hexaploid wheat. We performed mRNA and small RNA analyses in three tissues of nascent allohexaploid wheat and its following generations, their progenitors, and Chinese Spring.Among these samples, Samples 1-6 and 26-31, tetraploid progenitors; Samples 7-12 and 32-37, diploid progenitors; Samples 13-22 and 38-47, following generations; Samples 23-25 and 48-50, Chinese Spring.
Project description:DNA methylation predominantly occurs at CG dinucleotides in vertebrate genomes, however, non-CG methylation (mCH) is also detectable in vertebrate tissues, most notably in the nervous system. In mammalian brains, it is well established that: i) mCH is targeted to CAC trinucleotides by DNMT3A, ii) enriched in gene bodies and repetitive elements, and iii) associated with transcriptional repression. However, the possible conservation of these mCH features in zebrafish is largely unexplored and has yet to be functionally demonstrated. In this study, we analyse the transcriptomes (RNA-seq) and methylome (RRBS) of developing zebrafish larvae (1-6 weeks) and adult brain (6 month). We additionally elucidate a role for dnmt3aa/dnmt3ab in mCH deposition via CRISP/CAS9 KO and WGBS of 4 week old brains
Project description:Metastases arise from a multi-step process during which tumor cells change their mechanics in response to microenvironmental cues. While such mechanical adaptability could influence metastatic success, how tumor cell mechanics directly impacts intravascular behavior of circulating tumor cells (CTCs) remains poorly understood. In the present study, we demonstrate how the deformability of CTCs affects hematogenous dissemination and identify the mechanical profiles that favor metastatic extravasation. Combining intravital microscopy with CTC-mimicking elastic beads and mechanically-tuned tumor cells, we demonstrate that the inherent properties of circulating objects dictate their ability to enter constraining vessels. We identify cellular viscosity as the key property that governs CTC circulation and arrest patterns. We further demonstrate that cellular viscosity is required for efficient extravasation and find that properties that favor extravasation and subsequent metastatic outgrowth can be opposite. Altogether, we identify CTC viscosity as a key biomechanical parameter that shapes several steps of metastasis.