Dataset Information

In vivo single-cell CRISPR uncovers distinct TNF-α programs in tumor evolution

ABSTRACT: The tumor evolution model posits that malignant transformation is preceded by randomly distributed driver mutations in cancer genes, which cause clonal expansions in phenotypically normal tissues. Although clonal expansions can remodel entire tissues1-3, the mechanisms behind why only a small number of clones transform into malignant tumors remain enigmatic. Here, we develop an in vivo single-cell CRISPR strategy to systematically investigate tissue-wide clonal dynamics of the 150 most frequently mutated squamous cell carcinoma genes. We couple ultrasound-guided in utero lentiviral microinjections, single-cell RNA sequencing and guide capture to longitudinally monitor clonal expansions and document their underlying gene programs at single-cell transcriptomic resolution. We uncover a TNF-α signaling module, dependent on TNF receptor 1 and involving macrophages, that acts as a generalizable driver of clonal expansions in epithelial tissues. Conversely, during tumorigenesis, the TNF-α signaling module is downregulated. Instead, we identify a subpopulation of invasive cancer cells that switch to an autocrine TNF-α gene program, associated with epithelial-mesenchymal transition. Finally, we provide in vivo evidence that the autocrine TNF-α gene program is sufficient to mediate invasive properties and show that the TNF-α signature correlates with shorter overall survival in human squamous cell carcinoma patients. Collectively, our study demonstrates the power of applying in vivo single-cell CRISPR screening to mammalian tissues, unveils distinct TNF-α programs in tumor evolution and highlights the importance of understanding the relationship between clonal expansions in epithelia and tumorigenesis.

ORGANISM(S): Mus musculus

PROVIDER: GSE235325 | GEO | 2024/07/17

REPOSITORIES: GEO

ACCESS DATA

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Project description:Many aged individuals develop monoclonal expansions of CD8 T cells. These expansions are derived from a CD8 memory T cell that outcompetes neighboring CD8 T cells. The molecular alterations within clonal expansions that confer this competitive advantage relative to other CD8 T cells remains unknown. These microarray experiments were designed to identify genes differentially expressed in age-associated expansions of CD8 memory T cells relative to polyclonal CD8 memory T cells found in the same aged mice. Subsequent analysis of these data identified two major types of clonal expansions, distinguished by expression level of integrin a4 mRNA and protein. Based on this classification, Expansion_rep1 belongs to the integrin a4 high subtype of clonal expansions. In contrast, reps 2, 4, and 5 belong to the integrin a4 low subtype of clonal expansions. Given the divergent biological properties of these two subtypes of clonal expansions, we have focused genes differentially expressed between Expansion_rep 2, 4, and 5 and their paired PolyclonalAged samples. Experiment Overall Design: A total of 8 samples were analyzed for gene expression using the Affymetrix mouse genome 430 2.0 microarray platform. The experimental samples of interest were age-associated clonal expansions of CD8 memory T cells. We purified four clonal expansions from four independent, aged mice (indicated as "Expansion" rep1 2, 3, 4). For each clonal expansion of CD8 memory T cells that was purified, there was a paired control in which polyclonal CD8 memory T cells were harvested from the same aged mouse (denoted as "PolyclonalAged" rep1, 2, 3, 4). These paired samples allow one to consider gene expression changes from mice which have undergone the same age-associated changes in biology. The predominant comparison this study focused on was changes in gene expression between age-associated clonal expansions of CD8 memory T cells and their paired, polyclonal CD8 memory T cells. A total of 4 of these pairs were collected.

Dataset Information

In vivo single-cell CRISPR uncovers distinct TNF-α programs in tumor evolution

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure