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Rasko, J. E.

Publications and source records attributed to Rasko, J. E..

2 recordsLinked to original sources

Surveying Brain Tumor Heterogeneity by Single-Cell RNA Sequencing of Multi-sector Biopsies

Brain tumors are among the most challenging human tumors for which the mechanisms driving progression and heterogeneity remain poorly understood. We combined single-cell RNA-seq with multisector biopsies to sample and analyze single-cell expression profiles of gliomas from 13 Chinese patients. After classifying individual cells, we generated a spatial and temporal landscape of glioma that revealed the patterns of invasion between the different sub-regions of gliomas. We also used single-cell inferred CNVs and pseudotime trajectories to inform on the crucial branches that dominate tumor progression. The dynamic cell components of the multi-region biopsy analysis allowed us to spatially deconvolute with unprecedented accuracy the transcriptomic features of the core and those of the periphery of glioma at single cell level. Through this rich and geographically detailed dataset, we were also able to characterize and construct the chemokine and chemokine receptor interactions that exist among different tumor and non-tumor cells. This study provides the first spatial-level analysis of the cellular states that characterize human gliomas. It also presents an initial molecular map of the crosstalks between glioma cells and the surrounding microenvironment with single cell resolution.

genomics

Ctcf Haploinsufficiency Mediates Intron Retention in A Tissue-specific Manner

CTCF is a master regulator of gene transcription and chromatin organization with occupancy at thousands of DNA target sites. CTCF is essential for embryonic development and somatic cell viability and has been characterized as a haploinsufficient tumor suppressor. Increasing evidence demonstrates CTCF as a key player in several alternative splicing (AS) regulatory mechanisms, including transcription elongation, regulation of splicing factors, and epigenetic regulation. However, the genome-wide impact of Ctcf dosage on AS has not been investigated. We examined the effect of Ctcf haploinsufficiency on gene expression and AS in multiple tissues from Ctcf hemizygous (Ctcf+/-) mice. Distinct tissue-specific differences in gene expression and AS were observed in Ctcf+/- mice compared to wildtype mice. We observed a surprisingly large number of increased intron retention (IR) events in Ctcf+/- liver and kidney, specifically in genes associated with cytoskeletal organization, splicing and metabolism. This study provides further evidence for Ctcf dose-dependent and tissue-specific regulation of gene expression and AS. Our data provide a strong foundation for elucidating the mechanistic role of CTCF in AS regulation and its biological consequences.

molecular biology