No abstract

Human iPSC-derived mesenchymal stem cells (iMSCs) are an alternative to primary mesenchymal stem cells (MSCs), which have been a limited supply, and have attracted a great deal of interest as a promising cell source in cell-based therapy. However, despite their enormous therapeutic potential, it has been difficult to translate this potential into clinical applications due to the short viability duration of transplanted iMSCs. Therefore, to maximize the therapeutic effects of iMSCs, it is extremely important to extend their retention rate during and even after the transplantation. In this study, we developed a new extracellular matrix (ECM)-coating method involving the mild reduction of the cell surface. The reduction of disulfide bonds around the cell membrane enhanced the coating efficiency without a decrease in the viability and differentiation potential of iMSCs. We then induced ECM-coated single iMSCs to form three-dimensional spheroids via self-assembly of the aggregates within a physically confined microenvironment. The spheroids exhibited longer maintenance of the survival rate. Nanometric ECM coating of the cell membrane is a new approach as a key for resolving the conventional challenges of cell-based therapy.

Collagen is a prominent target of nonenzymatic glycation, which is a hallmark of aging and causes functional alteration of the matrix. Here, we uncover glycation‐mediated structural and functional changes in the collagen‐enriched meningeal membrane of the human and mouse brain. Using an in vitro culture platform mimicking the meningeal membrane composed of fibrillar collagen, we showed that the accumulation of advanced glycation end products (AGEs) in the collagen membrane is responsible for glycation‐mediated matrix remodeling. These changes influence fibroblast‐matrix interactions, inducing cell‐mediated ECM remodeling. The adherence of meningeal fibroblasts to the glycated collagen membrane was mediated by the discoidin domain‐containing receptor 2 (DDR2), whereas integrin‐mediated adhesion was inhibited. A‐kinase anchoring protein 12 (AKAP12)‐positive meningeal fibroblasts in the meningeal membrane of aged mice exhibited substantially increased expression of DDR2 and depletion of integrin beta‐1 (ITGB1). In the glycated collagen membrane, meningeal fibroblasts increased the expression of matrix metalloproteinase 14 (MMP14) and less tissue inhibitor of metalloproteinase‐1 (TIMP1). In contrast, the cells exhibited decreased expression of type I collagen (COL1A1). These results suggest that glycation modification by meningeal fibroblasts is intimately linked to aging‐related structural and functional alterations in the meningeal membrane.

Cancer secretome is a reservoir for aberrant glycosylation. How therapies alter this post-translational cancer hallmark and the consequences thereof remain elusive. Here we show that an elevated secretome fucosylation is a pan-cancer signature of both response and resistance to multiple targeted therapies. Large-scale pharmacogenomics revealed that fucosylation genes display widespread association with resistance to these therapies. In both cancer cell cultures and patients, targeted kinase inhibitors distinctively induced core fucosylation of secreted proteins less than 60 kDa. Label-free proteomics of N-glycoproteomes revealed that fucosylation of the antioxidant PON1 is a critical component of the therapy-induced secretome. Core fucosylation in the Golgi impacts PON1 stability and folding prior to secretion, promoting a more degradation-resistant PON1. Non-specific and PON1-specific secretome de-N-glycosylation both limited the expansion of resistant clones in a tumor regression model. Our findings demonstrate that core fucosylation is a common modification indirectly induced by targeted therapies that paradoxically promotes resistance.