Diseased skin dermal proteomic profiles reflect shared extracellular matrix dysregulation patterns

Extracellular matrix (ECM) plays a major role in the maintenance of skin homeostasis and modifications in its structure are commonly linked with skin diseases of different origins. Recent evidence shows that epidermal fibroblasts can be important regulators of epidermal pathology. However, despite recent advances, the intricate mechanisms responsible for the ECM defects in a wide range of skin pathologies are still evasive. In this work we used Dystrophic Epidermolysis Bullosa, Pemphigus vulgaris and Squamous Cell Carcinoma, as the models for epidermal diseases of distinct etiology, in order to explore potential shared alterations in diseased dermal fibroblasts. Our proteome analysis revealed that differentially expressed proteins in all diseases are commonly enriched in processes related to supramolecular fiber organization, complex of collagen trimers and actomyosin, however with opposite patterns. Nevertheless, Collagen XII is significantly downregulated in all diseases. Additionally, an algorithmic pipeline predicts that MAPKs and CDKs are major regulators of dermal proteome alterations across all diseases. Altogether, our results highlight a possible shared mechanism where downregulation of Collagen XII mediates ECM organization disruption leading to diverse disease phenotypes.