Neuroblastoma, a prevalent and aggressive childhood cancer, lacks effective treatments. Recent research highlights the repurposing of existing drugs as a strategy for breakthroughs in combating this disease. We systematically analyzed small-molecule perturbation gene expression data from the Library of Integrated Network-Based Cellular Signatures (LINCS), identifying pyrvinium pamoate and sirolimus, two FDA-approved drugs, as potential candidates for neuroblastoma combination therapy. Colony formation assays and organoid culture confirmed that the therapeutic effect of combining these two drugs exceeded that of either drug alone. The mRNA expression levels of several genes predicted by LINCS also decreased. To comprehensively understand the mechanism behind superior efficacy of the combination therapy compared to monotherapy, we performed quantitative proteomics with tandem mass tag labeling and identified 3416 proteins from 20,623 peptides. Gene set enrichment analysis and Database for Annotation, Visualization, and Integrated Discovery revealed that combination therapy significantly decreased cytoskeleton formation compared with monotherapy, reflecting dramatic reduction in cell migration. Additionally, the research indicated that cell cycle arrest occurred under combination therapy. Furthermore, we confirmed that the extent of autophagy significantly increased after the combination treatment. In summary, this study elucidates the mechanisms and therapeutic potential of combining sirolimus and pyrvinium pamoate for treating neuroblastoma, offering new advancements for this challenging disease.

Although cell-fate specification is generally attributed to transcriptional regulation, emerging data also indicate a role for molecules linked with intermediary metabolism. For example, α-ketoglutarate (αKG), which fuels energy production and biosynthetic pathways in the tricarboxylic acid (TCA) cycle, is also a co-factor for chromatin-modifying enzymes1-3. Nevertheless, whether TCA-cycle metabolites regulate cell fate during tissue homeostasis and regeneration remains unclear. Here we show that TCA-cycle enzymes are expressed in the intestine in a heterogeneous manner, with components of the αKG dehydrogenase complex4-6 upregulated in the absorptive lineage and downregulated in the secretory lineage. Using genetically modified mouse models and organoids, we reveal that 2-oxoglutarate dehydrogenase (OGDH), the enzymatic subunit of the αKG dehydrogenase complex, has a dual, lineage-specific role. In the absorptive lineage, OGDH is upregulated by HNF4 transcription factors to maintain the bioenergetic and biosynthetic needs of enterocytes. In the secretory lineage, OGDH is downregulated through a process that, when modelled, increases the levels of αKG and stimulates the differentiation of secretory cells. Consistent with this, in mouse models of colitis with impaired differentiation and maturation of secretory cells, inhibition of OGDH or supplementation with αKG reversed these impairments and promoted tissue healing. Hence, OGDH dependency is lineage-specific, and its regulation helps to direct cell fate, offering insights for targeted therapies in regenerative medicine.
© 2025. The Author(s).

Anti-sense oligonucleotides (ASOs) are modified synthetic single-stranded molecules with enhanced stability, activity, and bioavailability. They associate with RNA through sequence complementarity and can reduce or alter mRNA expression upon binding of splice site positions. To target RNA in the nucleus or cytoplasm, ASOs must cross membranes, a poorly understood process. We performed an unbiased CRISPR/Cas9 knockout screen with a genetic splice reporter to identify genes that can increase or decrease ASO activity, resulting in the most comprehensive catalog of ASO-activity modifier genes. Here we reveal distinct targets, including AP1M1 and TBC1D23, linking ASO activity to transport of cargo between the Golgi and endosomes. AP1M1 absence strongly increases ASO activity by delaying endosome-to-lysosome transport in vitro and in vivo. Prolonged ASO residence time in the endosomal system may increase the likelihood of ASO escape. This insight into AP1M1 role in ASO trafficking suggests a way for enhancing the therapeutic efficacy of ASOs by manipulating the endolysosomal pathways.
© 2025. The Author(s).

Differentiation of induced pluripotent stem cells (iPSCs) into specialized cell types is essential for uncovering cell-type specific molecular mechanisms and interrogating cellular function. Transcription factor screens have enabled efficient production of a few cell types; however, engineering cell types that require complex transcription factor combinations remains challenging. Here, we report an iterative, high-throughput single-cell transcription factor screening method that enables the identification of transcription factor combinations for specialized cell differentiation, which we validated by differentiating human microglia-like cells. We found that the expression of six transcription factors, SPI1, CEBPA, FLI1, MEF2C, CEBPB, and IRF8, is sufficient to differentiate human iPSC into cells with transcriptional and functional similarity to primary human microglia within 4 days. Through this screening method, we also describe a novel computational method allowing the exploration of single-cell RNA sequencing data derived from transcription factor perturbation assays to construct causal gene regulatory networks for future cell fate engineering.
© 2025. The Author(s).

The human breast is remarkably plastic and remodels with each birth to produce milk optimally suited for the changing demands of the newborn. This dynamic nature of lactation makes it challenging to study under controlled conditions. Given the health benefits of human milk, models of secretory mammary tissue would offer opportunities to study factors that influence this important food source. First, 3D models of the mammary duct/alveoli (D/A) were designed inspired by shapes found in vivo. Photoresins based on mammary decellularized extracellular matrix (dECM) were optimized to match the mechanical properties of native breast tissue. Next, these D/A models were printed with a volumetric printer and seeded with human milk-derived mammary epithelial cells (MECs). MECs formed stable epithelial layers on the printed surfaces and secreted the β-casein and milk fat globules. This model offers exciting avenues to explore hormonal, nutritional, and mechanobiological factors involved in lactation, thereby improving understanding of lactation for the benefit of infants and their mothers.