Spatial Mechano-Signaling Regulation of GTPases through Non-Degradative Ubiquitination.

Blood flow produces shear stress exerted on the endothelial layer of the vessels. Spatial characterization of the endothelial proteome is required to uncover the mechanisms of endothelial activation by shear stress, as blood flow varies in the vasculature. An integrative ubiquitinome and proteome analysis of shear-stressed endothelial cells demonstrated that the non-degradative ubiquitination of several GTPases is regulated by mechano-signaling. Spatial analysis reveals increased ubiquitination of the small GTPase RAP1 in the descending aorta, a region exposed to laminar shear stress. The ubiquitin ligase WWP2 is identified as a novel regulator of RAP1 ubiquitination during shear stress response. Non-degradative ubiquitination fine-tunes the function of GTPases by modifying their interacting network. Specifically, WWP2-mediated RAP1 ubiquitination at lysine 31 switches the balance from the RAP1/ Talin 1 (TLN1) toward RAP1/ Afadin (AFDN) or RAP1/ RAS Interacting Protein 1 (RASIP1) complex formation, which is essential to suppress shear stress-induced reactive oxygen species (ROS) production and maintain endothelial barrier integrity. Increased ROS production in endothelial cells in the descending aorta of endothelial-specific Wwp2-knockout mice leads to increased levels of oxidized lipids and inflammation. These results highlight the importance of the spatially regulated non-degradative ubiquitination of GTPases in endothelial mechano-activation.

Multi-Omics Integration for the Design of Novel Therapies and the Identification of Novel Biomarkers.

Multi-omics is a cutting-edge approach that combines data from different biomolecular levels, such as DNA, RNA, proteins, metabolites, and epigenetic marks, to obtain a holistic view of how living systems work and interact. Multi-omics has been used for various purposes in biomedical research, such as identifying new diseases, discovering new drugs, personalizing treatments, and optimizing therapies. This review summarizes the latest progress and challenges of multi-omics for designing new treatments for human diseases, focusing on how to integrate and analyze multiple proteome data and examples of how to use multi-proteomics data to identify new drug targets. We also discussed the future directions and opportunities of multi-omics for developing innovative and effective therapies by deciphering proteome complexity.

Divergent effects of peripheral and global neuropeptide Y deletion.

OBJECTIVES: Neuropeptide Y (NPY) is involved in the coordination of bone mass and adiposity. However, multiple NPY sources exist and their individual contribution to the skeleton and adiposity not known. The objectives of our study were to evaluate the effects of peripheral mesenchymal derived NPY to the skeleton and adiposity and to compare them to the global NPYKO model. METHODS: To study the role of mesenchymal-derived NPY, we crossed conditional NPY (NPYfl/fl) mice with Prx1cre to generate PrxNPYKO mice. The bone phenotype was assessed using micro-CT. The skeletal phenotype of PrxNPYKO mice was subsequently compared to global NPYKO model. We evaluated body weight, adiposity and functionally assessed the feeding response of NPY neurons to determine whether central NPY signaling was altered by Prx1cre. RESULTS: We identified the increase in cortical parameters in PrxNPYKO mice with no changes to cancellous bone. This was the opposite phenotype to global NPYKO mice generated from the same conditional allele. Male NPYKOmice have increased adiposity, while PrxNPYKO mice showed no difference, demonstrating that local mesenchymal-derived NPY does not influence adiposity. CONCLUSION: NPY mediates both positive and negative effects on bone mass via separate regulatory pathways. Deletion of mesenchymal-derived NPY had a positive effect on bone mass.

Targeting Stat3 signaling impairs the progression of bladder cancer in a mouse model.

Bladder cancer is the fourth most commonly diagnosed malignancy in men worldwide and has one of the highest recurrence rates of all cancers. This cancer type is unique because chronic inflammation caused by Schistosoma haematobium can cause bladder cancer, while inflammation induced by Bacillus Calmette Guerin is the therapeutic cornerstone for this cancer type. Activation of proinflammatory IL-6/Stat3 axis promotes the development of different cancers by acting on cancer cells as well as by modulating cancer microenvironment. Using a genetic and pharmacological approach in a mouse model, we demonstrated the importance of IL-6 and Stat3 signaling in bladder cancer. Our findings show that pharmacological inhibition of Stat3 with WP1066 effectively delays progression and invasiveness of bladder cancer in N-butyl-N-(4-hydroxybutyl) nitrosamine-induced mouse model. Moreover, either IL-6 blockade or Stat3 inhibition sensitized bladder cancer to anti-PD-L1 immune therapy. Taken together, our study demonstrates an important role of IL-6/Stat3 signaling in bladder cancer and creates a rationale for testing the therapeutic potential of Stat3 inhibitors in human MIBC both alone or in combination with anti-PD-L1 and anti-IL-6 therapy.

The dynamics of the inflammatory response during BBN-induced bladder carcinogenesis in mice.

BACKGROUND: Bladder cancer (BC) is the most common malignant disease of the urinary tract. Recurrent high grade non muscle invasive BC carries a serious risk for progression and subsequent metastases. The most common preclinical mouse model for bladder cancer relies on administration of N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) to mice. BBN-induced tumors in mice recapitulate the histology of human BC and were characterized with an overexpression of markers typical for basal-like cancer subtype in addition to a high mutational burden with frequent mutations in Trp53, similar to human muscle invasive BC. METHODS: Bladder cancer was induced in C57BL/6J male mice by administering the BBN in the drinking water. A thorough histopathological analysis of bladder specimen during and post BBN treatment was performed at 2, 4, 16, 20 and 25 weeks. RNA sequencing and qPCR was performed to assess the levels of expression of immunologically relevant genes at 2 weeks and 20 weeks during and post BBN treatment. RESULTS: We characterized the dynamics of the inflammatory response in the BBN-induced BC in mice. The treatment with BBN had gradually induced a robust inflammation in the first 2 weeks of administration, however, the inflammatory response was progressively silenced in the following weeks of the treatment, until the progression of the primary carcinoma. Tumors at 20 weeks were characterized with a marked upregulation of IL18 when compared to premalignant inflammatory response at 2 weeks. In accordance with this, we observed an increase in expression of IFNγ-responsive genes coupled to a pronounced lymphocytic infiltrate during the early stages of malignant transformation in bladder. Similar to human basal-like BC, BBN-induced murine tumors displayed an upregulated expression of immunoinhibitory molecules such as CTLA-4, PD-L1, and IDO1 which can lead to cytotoxic resistance and tumor escape. CONCLUSIONS: Despite the recent advances in bladder cancer therapy which include the use of checkpoint inhibitors, the treatment options for patients with locally advanced and metastatic BC remain limited. BBN-induced BC in mice displays an immunological profile which shares similarities with human MIBC thus representing an optimal model for preclinical studies on immunomodulation in management of BC.