Project description:Since loss of the NF2 tumor suppressor gene results in p21-activated kinase (Pak) activation, PAK inhibitors hold promise for the treatment of NF2-deficient tumors. To test this possibility, we asked if loss of Pak2, a highly expressed group I PAK member, affects the development of malignant mesothelioma in Nf2;Cdkn2a-deficient (NC) mice and the growth properties of NC mesothelioma cells in culture. In vivo, deletion of Pak2 resulted in a markedly decreased incidence and delayed onset of both pleural and peritoneal malignant mesotheliomas in NC mice. In vitro, Pak2 deletion decreased malignant mesothelioma cell viability, migration, clonogenicity, and spheroid formation. RNA-seq analysis demonstrated downregulated expression of Hedgehog and Wnt pathway genes in NC;Pak2-/- mesothelioma cells versus NC;Pak2+/+ mesothelioma cells. Targeting of the Hedgehog signaling component Gli1 or its target gene Myc inhibited cell viability and spheroid formation in NC;P+/+ mesothelioma cells. Kinome profiling uncovered kinase changes indicative of EMT in NC;Pak2-/- mesothelioma cells, suggesting that Pak2-deficient malignant mesotheliomas can adapt by reprogramming their kinome in the absence of Pak activity. The identification of such compensatory pathways offers opportunities for rational combination therapies to circumvent resistance to anti-PAK drugs.
Project description:Diffuse malignant peritoneal mesothelioma (DMPM) is a rapidly lethal malignancy. The comprehension of the molecular features of DMPM is of utmost importance for the fruitful management of the disease, especially in patients who fail standard treatments and have a poor prognosis due to the lack of effective alternative therapeutic options.
Project description:Malignant Peritoneal Mesothelioma (PeM) is a rare but frequently fatal cancer that originates from the peritoneal lining of the abdomen. Standard treatment of PeM is limited to cytoreductive surgery and/or chemotherapy, and no targeted therapies for PeM yet exist. This study performs comprehensive integrative analysis of genome, transcriptome, and proteome of treatment-naïve PeM tumors with the aim of identifying mesothelioma-related molecular alterations and potentially identifying novel treatment strategies.