FEBS Letters

Ríos Arceo, Carla; Drost, Jarno

doi: 10.1002/1873-3468.70188pmid: 41088832

Over the past decade, organoid technology has emerged as a transformative tool in biomedical research, enabling the development of physiologically relevant models of both healthy and malignant tissues. While this technology has substantially advanced our understanding of adult cancers, its application in pediatric oncology remains limited. Pediatric tumors are not only biologically distinct from adult malignancies but also present a lower incidence, posing additional challenges for model development. Despite these obstacles, recent efforts have led to the successful generation of organoids from various pediatric tumor types, offering new opportunities to explore disease mechanisms and therapeutic responses in a patient‐specific manner. In this Review, we summarize recent advances in organoid technology in pediatric cancer research, with a focus on its applications in preclinical and translational research. We also discuss current limitations and highlight emerging innovations that hold promise for further refining pediatric cancer models.

Kajiho, Hiroaki; Morioka, Shin; Sasaki, Junko; Sasaki, Takehiko

doi: 10.1002/1873-3468.70200pmid: 41121998

Comprehensive understanding of phosphoinositide signaling requires both spatiotemporal visualization and precise quantitative analysis of individual lipid species. Phosphoinositides, a family of phosphorylated derivatives of phosphatidylinositol (PI), are structurally diverse lipid messengers that orchestrate a wide range of cellular functions, including membrane trafficking, cytoskeletal dynamics, and signal transduction. Due to their dynamic metabolism and compartment‐specific localization, their analysis demands complementary strategies that integrate live‐cell imaging with molecular quantification. In this review, we first summarize the development and application of fluorescence‐based probes designed to monitor the distribution and dynamics of phosphoinositides in living cells, highlighting their specificity, targeting mechanisms, and limitations. We then provide an overview of recent advances in mass spectrometry‐based methodologies that enable high‐sensitivity, isomer‐resolved quantification of phosphoinositides in biological specimens, including improvements in lipid extraction, derivatization, and chromatographic separation. Together, these dual approaches offer synergistic insights into the biochemical and cellular regulation of phosphoinositide signaling.

Neyazi, Mastura; Samperio Ventayol, Pilar; Burkard, Natalie; Schlegel, Nicolas; Aguilar, Carmen; Bartfeld, Sina

doi: 10.1002/1873-3468.70182pmid: 41084327

Enteropathogenic E. coli (EPEC) attaches to host intestinal epithelial cells, resulting in severe illness and diarrhoea. Different cell models have been used to study EPEC infection, but a direct comparison of infection of cell lines and primary cells is lacking. In this study, we compare EPEC infection in primary epithelial cells with HeLa cells. Jejunal organoid‐derived cells contain differentiated intestinal epithelial cells and form a tight monolayer. Upon infection, they retain integrity over longer time periods than HeLa cells. Attachment of EPEC to host cells and innate immune response is strongly delayed in organoid‐derived monolayers. These results indicate that host cell factors determine the outcome of infection. Future identification of these host factors will aid the development of new therapeutics.

Alemany, Carla; Morel, Etienne

doi: 10.1002/1873-3468.70213pmid: 41168968

Phosphoinositides, a versatile class of phosphorylated phosphatidylinositols, are emerging as central orchestrators of cellular stress responses. Beyond defining the organization and identity of endomembranes, these dynamic lipids act as highly adaptable signaling hubs that integrate diverse stress cues, from nutrient deprivation and mechanical strain to osmotic imbalance and DNA damage. Across evolution—from unicellular organisms to mammals—they drive conserved adaptation programs, including vacuolar remodeling, endosomal trafficking, and autophagosome biogenesis, through a finely tuned metabolism governed by an intricate network of kinases, phosphatases, and regulatory partners. Recent advances uncover how compartment‐specific regulation, enzymatic diversity, and organelle crosstalk converge on phosphoinositide signaling, revealing these lipids as not only molecular adaptors but also promising therapeutic entry points in diseases marked by defective stress resolution. This review synthesizes emerging insights into the multifaceted roles of phosphoinositides in mobilizing membranes under stress, with a focus on mechanistic principles and recent research.

Bancilhon, Marie Déborah; Mesmin, Bruno

doi: 10.1002/1873-3468.70189pmid: 41084351

Phosphoinositides are scarce but dynamic lipids within the cell. They play crucial roles in regulating membrane dynamics and identity, intracellular trafficking, and signal transduction. These functions are coordinated through their distribution and turnover by phosphoinositide‐kinases, phosphatases, and lipid‐transfer proteins, which also act as key mediators in these processes. Viruses are obligate intracellular pathogens that have developed strategies to hijack the host cellular machinery, including lipid metabolic pathways, to support their replication. During viral infection, they take advantage of phosphoinositides to accomplish various steps of their cycle, such as entry, formation of replication organelles, assembly, and egress. Having such an important role in the viral cycle, targeting phosphoinositide metabolism has emerged as an interesting antiviral strategy over the years. This Review provides insight into the versatility of phosphoinositides during viral infection, presenting their involvement in the viral life cycle, their role as mediators of antiviral immunity, and their potential as a novel approach to antiviral development.

Nakayama, Shogo; Morimoto, Mitsuru

doi: 10.1002/1873-3468.70179pmid: 41084368

During organogenesis, the anterior foregut of the mammalian embryo undergoes morphological changes that give rise to the ventral trachea and the dorsal esophagus. Subsequently, the trachea on the ventral side functions as an air passage between the larynx and the bronchi, whereas the esophagus on the dorsal side develops a lumen to transport food from the pharynx to the stomach. Although mouse genetics has provided insights into various cell–cell interaction signals involved in the development of the trachea and esophagus, the exact mechanism remains elusive. Additionally, differences in tissue structure, cellular components, and developmental processes between species make it difficult to understand human development using animal models. However, human organoid technology has been developing rapidly over the past decade and is recognized as a technology that contributes to the elucidation of human organogenesis. This Review highlights our current understanding of the development and homeostasis of the trachea and esophagus. We also discuss the application of airway and esophageal organoids, which can help us better understand human organogenesis.

Xing, Changchang; Wang, Chao; Chen, Yuanyuan; Cheng, Weiwei; Jiang, Zhaolei; Chen, Alex F.; Fu, Chenglai

doi: 10.1002/1873-3468.70192pmid: 41126700

Inositol phosphates (InsPs) are intracellular signaling molecules that are essential for life. Inositol pyrophosphates, a subset of inositol phosphates, are the end products of inositol phosphate metabolism. In mammalian cells, up to 90% of inositol pyrophosphates are 5‐diphosphoinositol 1,2,3,4,6‐pentakisphosphate (5PP‐InsP5), which is generated by inositol hexakisphosphate kinases (IP6Ks). 5PP‐InsP5 can be further phosphorylated by diphosphoinositol pentakisphosphate kinases (PPIP5Ks) to generate 1,5‐bisdiphosphoinositol 2,3,4,6‐tetrakisphosphate (InsP8). Unlike freely diffusible molecules, 5PP‐InsP5 and InsP8 act locally at the sites where they are synthesized. Thus, individual IP6K and PPIP5K enzymes perform specific functions. Preclinical and clinical studies suggest that these molecules contribute to early life development, but mediate age‐related diseases beyond adulthood. In this review, we summarize the functions and mechanisms of action of every individual IP6K and PPIP5K in both physiological processes and diseases and discuss the potential applications of these inositol pyrophosphate kinases as druggable targets for disease treatment.