Understanding the biological and molecular processes underlying human pathologies is fundamental in order to develop innovative approaches to treat or prevent them. Among the technologies that could provide innovative disease models, induced pluripotent stem cells (iPSCs) is one of the most promising. Indeed, one application of this technology is patient-specific disease modeling. iPSCs obtained by reprogramming patients’ cells collected from accessible tissues, have the unique capability to differentiate, under an adequate stimulus, into any human cell type. In particular, iPSCs technology can be applied to study drug adverse effects, that is a key part of the drug discovery process. Indeed, drug induced adverse effects are among the most common causes that lead to abandon the development of new candidate therapeutic molecules, increasing the cost of drug discovery. An innovative strategy that could be used in drug design to solve drug attrition rate, and to establish innovative pharmacological models, could be the application of iPSCs technology in the early stage of the drug discovery process to model druginduced adverse events. In this review, recently developed disease models based on iPSCs will be discussed, with a particular focus on available models of drugs’ adverse effect, in particular hepatic/pancreatic toxicity.

Crohn's disease is a debilitating and incurable chronic inflammatory bowel disease, affecting millions of individuals worldwide, with an increasing frequency. Surgery must be applicable in half of the cases often with a disabling course, and pharmacological treatments may have adverse complications. We generated three isogenic clones of iPSCs from peripheral blood mononuclear cells (PBMCs) of a patient with Crohn's Disease under pharmacological treatment without adverse effects. Sendai virus based vector was used and the iPSCs were characterized for genetic uniqueness, genomic integrity, pluripotency, and differentiation ability. These iPSCs will be a powerful tool to develop tailored therapies.

Thiopurines, immunomodulating drugs used in the management of different chronic autoimmune conditions and as anti-leukemic agents, may exert in some cases gastrointestinal toxicity. Moreover, since these agents are administered orally, they are absorbed across the gastrointestinal tract epithelium. On these premises, cellular and molecular events occurring in intestinal cells may be important to understand thiopurine effects. However, quantitative information on the biotransformation of thiopurines in intestinal tissues is still limited. To shed light on biotransformation processes specific of the intestinal tissue, in this study thiopurine metabolites concentrations were analyzed by an in vitro model of human healthy colon, the HCEC cell line, upon exposure to cytotoxic concentrations of azathioprine or mercaptopurine; the investigation was carried out using an innovative mass spectrometry method, that allowed the simultaneous quantification of 11 mono-, di-, and triphosphate thionucleotides. Among the 11 metabolites evaluated, TIMP, TGMP, TGDP, TGTP, MeTIMP, MeTIDP and MeTITP were detectable in HCEC cells treated with azathioprine or mercaptopurine, considering two different incubation times before the addition of the drugs (4 and 48 h). Different associations between metabolites concentrations and cytotoxicity were detected. In particular, the cytotoxicity was dependent on the TGMP, TGDP, TGTP and MeTITP concentrations after the 4 h incubation before the addition of thiopurines. This may be an indication that, to study the association between thiopurine metabolite concentrations and the cytotoxicity activity in vitro, short growth times before treatment should be used. Moreover, for the first time our findings highlight the strong correlation between cytotoxicity and thiopurine pharmacokinetics in HCEC intestinal cells in vitro suggesting that these cells could be a suitable in vitro model for studying thiopurine intestinal cytotoxicity.

Neuronal innervation of the pancreas has historically been characterized using marker‐based classification and physiological studies, but its transcriptomic landscape remains only partially explored. A detailed molecular profile of pancreatic sensory neurons could provide insights into their role in health and disease, particularly in pancreatic ductal adenocarcinoma (PDAC), where neural remodeling influences tumor progression and pain signaling. Wild‐type and PDAC mice were injected with the retrotracer Fast Blue into pancreatic or cancerous tissue. Dorsal root ganglia were dissociated, and Fast Blue‐positive sensory neurons were isolated, lysed, and analyzed using single‐cell RNA sequencing. Data were validated using immunofluorescence, organoid cultures and qPCR. We performed transcriptomic profiling of sensory neurons innervating the pancreatic head and tail under normal and cancer conditions. Our analysis identified neurofilament‐containing neurons as the predominant sensory subtype in both contexts, while non‐peptidergic neurons were underrepresented in tumor‐associated innervation. Differential gene expression analysis revealed a unique subset of genes upregulated in sensory neurons innervating pancreatic tumors, many linked to mitochondrial activity. Further validation also revealed the presence of transcripts transferred via extracellular vesicles (including the Pdx1‐CreERT2 transgene from the KPC mouse model), suggesting a novel mechanism of tumor–neuron interaction. Our findings provide a detailed characterization of pancreatic and pancreatic ductal adenocarcinoma sensory innervation. We identified tumor‐derived RNA within sensory neurons in the PDAC mouse model, suggesting an extracellular vesicle–mediated RNA transfer mechanism that may remodel sensory signaling and open new prospects for diagnostic and therapeutic innovation in PDAC. Impact statement: Transcriptomic profiling of pancreatic sensory neurons reveals shifts in neuronal populations, tumor‐specific mitochondrial gene upregulation, and potential extracellular vesicle–mediated transcript transfer. Circulating tumor transcripts in KPC mice provide a reference for pancreatic innervation, tumor–nerve interactions, and therapeutic targets.