Adequate availability of cellular building blocks, including lipids, is a prerequisite for cellular proliferation, but excess dietary lipids are linked to increased cancer risk. Despite these connections, specific regulatory relationships between membrane composition, intestinal stem cell (ISC) proliferation, and tumorigenesis are unclear. We reveal an unexpected link between membrane phospholipid remodeling and cholesterol biosynthesis and demonstrate that cholesterol itself acts as a mitogen for ISCs. Inhibition of the phospholipid-remodeling enzyme Lpcat3 increases membrane saturation and stimulates cholesterol biosynthesis, thereby driving ISC proliferation. Pharmacologic inhibition of cholesterol synthesis normalizes crypt hyperproliferation in Lpcat3-deficient organoids and mice. Conversely, increasing cellular cholesterol content stimulates crypt organoid growth, and providing excess dietary cholesterol or driving endogenous cholesterol synthesis through SREBP-2 expression promotes ISC proliferation in vivo. Finally, disruption of Lpcat3-dependent phospholipid and cholesterol homeostasis dramatically enhances tumor formation in Apc mice. These findings identify a critical dietary-responsive phospholipid-cholesterol axis regulating ISC proliferation and tumorigenesis.
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http://dx.doi.org/10.1016/j.stem.2017.12.017 | DOI Listing |
Cell Mol Gastroenterol Hepatol
December 2024
Departments of Molecular & Integrative Physiology; Internal Medicine, University of Michigan, Ann Arbor, MI. Electronic address:
Intestinal stem cells replenish the epithelium throughout life by continuously generating intestinal epithelial cell types, including absorptive enterocytes, and secretory goblet, endocrine, and Paneth cells. This process is orchestrated by a symphony of niche factors required to maintain intestinal stem cells and to direct their proliferation and differentiation. Among the various mature intestinal epithelial cell types, Paneth cells are unique in their location in the stem cell zone, directly adjacent to intestinal stem cells.
View Article and Find Full Text PDFJ Transl Med
December 2024
Department of Gastroenterology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200080, China.
Background: Yes-associated protein 1 (YAP1) regulates the survival, proliferation, and stemness of cells, and contributes to the development of metabolic dysfunction associated fatty liver disease (MAFLD). However, the regulatory role of intestinal YAP1 in MAFLD still remains unclear.
Methods: Terminal ileal specimens were used to compare intestinal YAP1 activation in patients with and without MAFLD.
J Pathol
January 2025
Institut de Recherche en Santé Digestive (IRSD), Université de Toulouse, INSERM, INRAE, ENVT, UPS, Toulouse, France.
Patients with familial adenomatous polyposis (FAP) harbor mutations in the APC gene and will develop adenoma and early colorectal cancer. There is no validated treatment, and animal models are not sufficient to study FAP. Our aim was to investigate the early events associated with FAP using the intestinal organoid model in a single-center study using biopsies from nonadenomatous and adenomatous colonic mucosa of FAP patients and from healthy controls (HCs).
View Article and Find Full Text PDFCells
November 2024
Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, Louisiana Cancer Research Center, New Orleans, LA 70112, USA.
Understanding the regulation of somatic stem cells, both during homeostasis and in response to environmental challenges like injury, infection, chemical exposure, and nutritional changes, is critical because their dysregulation can result in tissue degeneration or tumorigenesis. The use of models such as the and mammalian adult intestines offers valuable insights into tissue homeostasis and regeneration, advancing our knowledge of stem cell biology and cancer development. This review highlights significant findings from recent studies, unveiling the molecular mechanisms that govern self-renewal, proliferation, differentiation, and regeneration of intestinal stem cells (ISCs).
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