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Procopio, P.

Publications and source records attributed to Procopio, P..

3 recordsLinked to original sources

Western diet suppresses canonical intestinal stem cells and reprograms c-Kit+ reserve stem cells via proinflammatory dysbiosis

While colorectal cancer (CRC) is thought to originate primarily from resident stem cells, diet heavily influences intestinal stem cell homeostasis and disease onset. In this study, we demonstrate that a Western-style diet (WSD) alters intestinal homeostasis by uncoupling canonical stemness from tumorigenesis. WSD exposure suppresses canonical Lgr5 stem cells while activating an alternative pool of facultative c-Kit secretory cells. Although these reprogrammed stem-like cells exhibit genotoxic stress, they remain proliferative under prolonged dietary exposure, suggesting increased susceptibility to tumor-initiating mutations. We identify diet-induced microbial shifts and the expansion of enterotoxigenic Bacteroides fragilis (ETBF) as the upstream driver. ETBF and its toxin fragilysin autonomously trigger multipotency in c-Kit+ cells through Wnt/{beta}-catenin and YAP signaling. Importantly, these alterations are fully reversible upon dietary intervention. Together, our results highlight a targetable dietary-microbial axis that shapes epithelial stemness and underscores the role of facultative stem cells in diet-induced CRC onset.

cell biology↗

The origin of intestinal cancer in the context of inflammation

According to conventional views, colon cancer originates from stem cells. However, inflammation, a key risk factor for colon cancer, was shown to suppress intestinal stemness. Here, we employed Paneth cells (PCs) as a model to assess the capacity of differentiated lineages to trigger tumorigenesis in the context of inflammation. Upon inflammation, PC-specific Apc mutations led to intestinal tumors reminiscent not only of those arising in inflammatory bowel disease (IBD) patients but also of a larger fraction of sporadic colon cancers. The latter is likely due to the inflammatory consequences of Western-style dietary habits, the major colon cancer risk factor. Computational methods designed to predict the cell-of-origin of cancer confirmed that, in a substantial fraction of sporadic colon cancers the cells-of-origin are secretory lineages and not stem cells. One-Sentence SummarySecretory cell lineages trigger tumor formation in the context of the major etiologic colon cancer risk factors.

cancer biology↗

Targeting SerpinE1 reverses cellular features of Hutchinson-Gilford progeria syndrome

Hutchinson-Gilford progeria syndrome (HGPS) is a rare, fatal disease caused by Lamin A mutation, leading to altered nuclear architecture, loss of perinuclear heterochromatin and deregulated gene expression. HGPS patients eventually die by coronary artery disease and cardiovascular alterations. However, how deregulated transcriptional networks at the cellular level impact on the systemic disease phenotype is currently unclear. We have performed a longitudinal genome-wide analysis of gene expression in primary HGPS fibroblasts from patients at two sequential stages of disease that revealed a progressive activation of Rho signaling and SerpinE1, also known as Plasminogen Activator Inhibitor (PAI-1). siRNA-mediated downregulation or pharmacological inhibition of SerpinE1 by TM5441 could revert key pathological features of HGPS in patient-derived fibroblasts, including re-activation of cell cycle progression, reduced DNA damage signaling, decreased expression of pro-fibrotic genes and recovery of mitochondrial defects. These effects were accompanied by reduced levels of Progerin and correction of nuclear abnormalities. These data point to SerpinE1 as a novel potential effector of HGPS pathogenesis and target for therapeutic interventions.

cell biology↗