Selvestrel, D. | bioRxiv Science

bioRxiv2025

Human liver organoids uncover ductular reaction in Wolman disease and inform gene therapy design

Wolman disease (WD), the severe infantile form of lysosomal acid lipase deficiency, is a rare metabolic disorder caused by inactivating mutations in the LIPA gene. Although WD is characterized by profound hepatic dysfunction, experimental human systems capable of modelling multicellular liver pathology and supporting therapeutic testing remain limited. Here, we generated an isogenic human model of WD by introducing LIPA loss-of-function mutations into induced pluripotent stem cells and differentiating them into multicellular human liver organoids (HLO). LIPA-deficient HLO preserved hepatic lineage specification while recapitulating key biochemical and cellular features of WD, including loss of LIPA activity, lysosomal expansion, lipid accumulation, and activation of inflammatory and fibrogenic programs. Single-cell RNA sequencing resolved cell-type-specific disease states across hepatocyte-, stromal-, and biliary-like populations, revealing the emergence of a reactive biliary program consistent with ductular reaction, a complex tissue response associated with chronic liver injury. Importantly, this reactive biliary phenotype was supported by targeted gene-expression analysis in WD liver organoids and independently validated in liver tissue from mouse models and WD patients. Isolated LIPA-deficient cholangiocyte organoids failed to reproduce the DR-associated program, indicating that this response depends on multicellular interactions within the hepatic microenvironment rather than on biliary cell-autonomous dysfunction alone. Consistently, hepatocyte-directed AAV-mediated restoration of LIPA expression attenuated metabolic stress, inflammatory and fibrogenic programs, and suppressed ductular reaction both in organoids and in vivo. Together, these findings establish multicellular human liver organoids as a physiologically relevant platform for modelling emergent tissue-level responses in WD and for evaluating therapeutic rescue strategies in a human context.

pathology↗

bioRxiv2024

Drug-repurposing screen identifies thiostrepton as a novel regulator of the tumor suppressor DAB2IP

The tumor suppressor DAB2IP, a RasGAP and cytoplasmic adaptor protein, modulates signal transduction in response to several extracellular stimuli, negatively regulating multiple oncogenic pathways. Accordingly, the loss of DAB2IP in tumor cells fosters metastasis and enhances chemo- and radio-resistance. DAB2IP is rarely mutated in cancer but is frequently downregulated or inactivated by multiple mechanisms. Solid experimental evidence show that DAB2IP reactivation can reduce cancer aggressiveness in tumors driven by multiple different oncogenic mutations, making this protein an interesting target for anti-cancer therapy. Based on these premises, we screened a library of FDA-approved drugs to search for molecules that can increase DAB2IP protein levels. We exploited CRISPR/Cas9 gene editing to generate two prostate cancer cell models in which endogenous DAB2IP is fused to HiBiT, a peptide tag that enables luminescence-based detection of protein levels in a sensitive and quantitative manner. Using this approach, we identified drugs able to increase DAB2IP levels. We focus our attention on thiostrepton, a natural cyclic oligopeptide antibiotic that has been reported to inhibit survival of various cancer cell lines. Functional experiments revealed that the cancer inhibitory effect of thiostrepton is reduced in the absence of DAB2IP, suggesting that the observed upregulation contributes to its action. These findings encourage the further development of thiostrepton for the treatment of solid cancers, and unveil a novel molecular mechanism underlying its anti-tumoral action.

cancer biology↗