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Masuda, K.

Publications and source records attributed to Masuda, K..

2 recordsLinked to original sources

The repertoire of serous ovarian cancer non-genetic heterogeneity revealed by single-cell sequencing of normal fallopian tube epithelial cells

The inter-differentiation between cell states promotes cancer cell survival under stress and fosters non-genetic heterogeneity (NGH). NGH is, therefore, a surrogate of tumor resilience but its quantification is confounded by genetic heterogeneity. Here we show that NGH can be accurately measured when informed by the molecular signatures of the normal cells of origin. We surveyed the transcriptomes of [~] 4000 normal fallopian tube epithelial (FTE) cells, the cells of origin of serous ovarian cancer (SOC), and identified six FTE subtypes. We used subtype signatures to deconvolute SOC expression data and found substantial intra-tumor NGH that was previously unrecognized. Importantly, NGH-based stratification of [~]1700 tumors robustly predicted survival. Our findings lay the foundation for accurate prognostic and therapeutic stratification of SOC.\n\nHighlightsO_LIThe projection of FTE subtypes refines the molecular classification of serous OC\nC_LIO_LIComprehensive single-cell profiling of FTE cells identifies 6 molecular subtypes\nC_LIO_LISubstantial non-genetic heterogeneity of HGSOC identified in 1700 tumors\nC_LIO_LIA mesenchymal-high HGSOC subtype is robustly correlated with poor prognosis\nC_LI

cancer biology

Dissecting the functions of NIPBL using genome editing: The importance of the N-terminus of NIPBL in transcriptional regulation

Cornelia de Lange syndrome (CdLS) is characterized by craniofacial dysmorphisms, intellectual disabilities, growth retardation, and several other systemic abnormalities. CdLS is caused by heterozygous germline mutations in structural and regulatory components of cohesin. Mutations in NIPBL, which encodes regulatory subunit of cohesin, are frequently found in individuals with CdLS. CdLS is associated with a currently unknown mechanism of global transcriptional dysregulation. In this study, NIPBL mutants were generated using the CRISPR/Cas9 system to study this mechanism. Clones with a biallelic frameshift mutation in exon 3 of NIPBL, resulting in a truncated N-terminus, displayed transcriptional dysregulation without sister chromatid separation defects. Detailed transcriptome analysis revealed the overexpression of genes in NIPBL mutants that are typically expressed at low levels in wild type and the reduced expression of genes that are typically expressed at high levels in wild type. This result suggested that NIPBL plays a role in fine-tuning gene expression levels. MAU2 protein, that closely interacts with NIPBL, was nearly absent in these clones. The reduction of MAU2 observed in NIPBL mutants points to the importance of the NIPBL N-terminus/MAU2 interaction in transcriptional regulatory role of NIPBL.

genetics