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Biology subjects

Nipper, M.

Publications and source records attributed to Nipper, M..

2 recordsLinked to original sources

NF2 loss malignantly transforms human pancreatic acinar cells and enhances cell fitness under environmental stress

Pancreatic ductal adenocarcinoma (PDAC) occurs as a complex, multifaceted event driven by the interplay of tumor permissive genetic mutations, nature of cellular origin and microenvironmental stress. In this study, using primary human pancreatic acinar 3D organoids, we performed CRISPR knockout screen targeting 199 previously underappreciated potential tumor suppressors curated from clinical PDAC samples. Our data revealed significant enrichment of a list of candidates, with NF2 emerging as the top target. Functional validation confirmed that loss of NF2 promotes the transition of PDAC to an invasive state, potentially through extracellular matrix modulation. NF2 inactivation was found to enhance PDAC cell fitness under nutrient starvation. This adaptation not only reinforces the oncogenic state but also confers therapeutical resistance. Additionally, we found that NF2 loss is associated with the fibroblast heterogeneity and cancer-stroma communications in tumor evolution. These findings establish NF2 as a critical tumor suppressor in PDAC and uncover its role in mediating nutrient adaptation and drug resistance. Importantly, this study provides new insights into drug resistance mechanisms and potential therapeutic targets in PDAC.

cancer biology↗

Deletion of Lats 1 and 2 in mouse pancreatic acinar cells induces pancreatic fibrosis and inflammation

ObjectiveThe Hippo signaling pathway is known for regulating proliferation, differentiation, organ size, and tumorigenesis. Large tumor suppressor kinase 1 and 2 (LATS1&2) are the core kinases of this pathway, whose functions in both the normal pancreas and pancreatic diseases are unclear. We studied the function of LATS1&2 specifically in pancreatic acinar cells of adult mice. DesignWe generated mice with adult pancreatic acinar cell-specific deletion of Lats1&2 genes by using CreER/LoxP. Pancreata were analyzed by histological examination, immunostaining, western blot, and RNA-sequencing. ResultsDeletion of Lats1&2 genes in adult pancreatic acinar cells resulted in rapid development of pancreatic inflammation and fibrosis. Loss of Lats1&2 did not directly induce acinar cell proliferation or apoptosis, but resulted in pancreatic stellate cell (PSC) activation followed by immune cell infiltration and acinar-to-ductal metaplasia. These effects were mediated by the Hippo downstream effectors YAP1/TAZ. By using neutralizing antibody to block CTGF, a YAP1/TAZ target, the inflammation and fibrosis were reduced. Our RNA-sequencing data identified upregulation of fibroinflammatory genes in Lats1&2 null pancreata, which may play important roles in stimulating PSC activation and promoting pancreatic fibrosis, as well as inflammation. ConclusionsDeletion of the Lats1&2 genes from adult acinar cells leads to the YAP1/TAZ dependent upregulation of a fibroinflammatory program. Our results emphasize the critical role of Lats1&2 in regulating PSC activation. Our findings identify new strategies for controlling pancreatic inflammation and fibrosis in diseases such as pancreatitis and pancreatic cancer.

molecular biology↗