S100A4-neutralizing monoclonal antibody 6B12 counteracts the established experimental skin fibrosis induced by bleomycin

The multi-faceted immune modulatory role of S100A4 in cancer and chronic inflammatory disease

S100A4 is a Ca2+-binding protein involved in multiple chronic inflammatory and neoplastic conditions. This review focuses on recent advances in the understanding of S100A4 function in immune cells, comparing and contrasting S100A4 regulation of immune responses in cancer and chronic inflammatory diseases. We provide evidence that S100A4 regulation of immune cell function has a profound role in promoting the pathogenesis of cancer and pro-inflammatory conditions. Finally, we discuss relevant future directions to target S100A4 therapeutically in different disease states.

The RAGE Pathway in Skin Pathology Development: A Comprehensive Review of Its Role and Therapeutic Potential

The receptor for advanced glycation end-products (RAGE), a member of the immunoglobulin superfamily, is expressed in various cell types and mediates cellular responses to a wide range of ligands. The activation of RAGE triggers complex signaling pathways that drive inflammatory, oxidative, and proliferative responses, which are increasingly implicated in the pathogenesis of skin diseases. Despite its well-established roles in conditions such as diabetes, cancer, and chronic inflammation, the contribution of RAGE to skin pathologies remains underexplored. This review synthesizes current findings on RAGE's involvement in the pathophysiology of skin diseases, including conditions such as psoriasis, atopic dermatitis, and lichen planus, focusing on its roles in inflammatory signaling, tissue remodeling, and skin cancer progression. Additionally, it examines RAGE-modulating treatments investigated in dermatological contexts, highlighting their potential as therapeutic options. Given RAGE's significance in a variety of skin conditions, further research into its mediated pathways may uncover new opportunities for targeted interventions in skin-specific RAGE signaling.

Emerging therapeutic targets in systemic sclerosis

Systemic sclerosis is an autoimmune connective tissue disease which is characterised by vascular perturbations, inflammation, and fibrosis. Although huge progress recently into the underlying molecular pathways that are perturbed in the disease, currently no therapy exists that targets the fibrosis element of the disease and consequently there is a huge unmet medical need. Emerging studies reveal new dimensions of complexity, and multiple aberrant pathways have been uncovered that have shed light on disturbed signalling in the disease, primarily in inflammatory pathways that can be targeted with repurposed drugs. Pre-clinical animal models using these inhibitors have yielded proof of concept for targeting these signalling systems and progressing to clinical trials. This review will examine the recent evidence of new perturbed pathways in SSc and how these can be targeted with new or repurposed drugs to target a currently intractable disease.

S100A4 a classical DAMP as a therapeutic target in fibrosis

Fibrosis regardless of aetiology is characterised by persistently activated myofibroblasts that are contractile and secrete excessive amounts of extracellular matrix molecules that leads to loss of organ function. Damage-Associated Molecular Patterns (DAMPs) are endogenous host-derived molecules that are released from cells dying or under stress that can be triggered by a variety of insults, either chemical or physical, leading to an inflammatory response. Among these DAMPs is S100A4, part of the S100 family of calcium binding proteins that participate in a variety of cellular processes. S100A4 was first described in context of cancer as a pro-metastatic factor. It is now appreciated that aside from its role in cancer promotion, S100A4 is intimately involved in tissue fibrosis. The extracellular form of S100A4 exerts its effects through multiple receptors including Toll-Like Receptor 4 and RAGE to evoke signalling cascades involving downstream mediators facilitating extracellular matrix deposition and myofibroblast generation and can play a role in persistent activation of myofibroblasts. S100A4 may be best understood as an amplifier of inflammatory and fibrotic processes. S100A4 appears critical in systemic sclerosis pathogenesis and blocking the extracellular form of S100A4 in vivo in various animal models of disease mitigates fibrosis and may even reverse established disease. This review appraises S100A4's position as a DAMP and its role in fibrotic conditions and highlight therapeutically targeting this protein to halt fibrosis, suggesting that it is a tractable target.