Zonation of Ribosomal DNA Transcription Defines a Stem Cell Hierarchy in Colorectal Cancer.

Zonation of Ribosomal DNA Transcription Defines a Stem Cell Hierarchy in Colorectal Cancer. Cell Stem Cell. 2020 May 10;: Authors: Morral C, Stanisavljevic J, Hernando-Momblona X, Mereu E, Álvarez-Varela A, Cortina C, Stork D, Slebe F, Turon G, Whissell G, Sevillano M, Merlos-Suárez A, Casanova-Martí À, Moutinho C, Lowe SW, Dow LE, Villanueva A, Sancho E, Heyn H, Batlle E Abstract Colorectal cancers (CRCs) are composed of an amalgam of cells with distinct genotypes and phenotypes. Here, we reveal a previously unappreciated heterogeneity in the biosynthetic capacities of CRC cells. We discover that the majority of ribosomal DNA transcription and protein synthesis in CRCs occurs in a limited subset of tumor cells that localize in defined niches. The rest of the tumor cells undergo an irreversible loss of their biosynthetic capacities as a consequence of differentiation. Cancer cells within the biosynthetic domains are characterized by elevated levels of the RNA polymerase I subunit A (POLR1A). Genetic ablation of POLR1A-high cell population imposes an irreversible growth arrest on CRCs. We show that elevated biosynthesis defines stemness in both LGR5+ and LGR5- tumor cells. Therefore, a common architecture in CRCs is a simple cell hierarchy based on the differential capacity to transcribe ribosomal DNA and synthesize proteins. PMID: 32396863 [PubMed - as supplied by publisher]
Source: Cell Stem Cell - Category: Stem Cells Authors: Tags: Cell Stem Cell Source Type: research