Development of a 3D Skin Model for Studying Melanoma Progression.

Despite advances in the treatment of cutaneous melanoma, there is still a high percentage of patients who fail to respond or develop resistance to treatment. Establishing robust in vitro melanoma models will enable mechanism-based drug screening while reducing animal testing. In this work, a three-dimensional (3D) melanoma skin model (3DMSM) was developed on a porous scaffold. The culture of three melanoma cell lines (SKMEL-1, A375, and G361) in co-culture with human fibroblasts, melanocytes, and keratinocytes allowed the formation of the dermis, and stratified epidermis. Tumors were established in this model using two methodologies: adding previously formed melanoma cell aggregates (CA) or seeding melanoma cells directly into the dermis (CD). In this model, melanoma cells remain in their original microenvironment and, after proliferation, invade the basal layer. The model recapitulates correct melanocyte localization, epidermal disruption, extracellular matrix (ECM) remodeling, including collagen deposition, and epithelial-to-mesenchymal transition (EMT). Additionally, the cytokine profiles studied indicate that the model could mirror the inflammatory and immune-evasive traits of melanoma. Overall, 3DMSM provides a useful tool for understanding the mechanisms of melanoma progression and invasion, and for developing personalized medicine strategies through the implementation of a patient-derived model.