A Preclinical Model of Cutaneous Melanoma Based on Reconstructed Human Epidermis

Abstract

Malignant melanoma is among the tumor entities with the highest increase of incidence worldwide. To elucidate melanoma progression and develop new effective therapies, rodent models are commonly used. While these do not adequately reflect human physiology, two-dimensional cell cultures lack crucial elements of the tumor microenvironment. To address this shortcoming, we have developed a melanoma skin equivalent based on an open-source epidermal model. Melanoma cell lines with different driver mutations were incorporated into these models forming distinguishable tumor aggregates within a stratified epidermis. Although barrier properties of the skin equivalents were not affected by incorporation of melanoma cells, their presence resulted in a higher metabolic activity indicated by an increased glucose consumption. Furthermore, we re-isolated single cells from the models to characterize the proliferation state within the respective model. The applicability of our model for tumor therapeutics was demonstrated by treatment with a commonly used v-raf murine sarcoma viral oncogene homolog B (BRAF) inhibitor vemurafenib. This selective BRAF inhibitor successfully reduced tumor growth in the models harboring BRAF-mutated melanoma cells. Hence, our model is a promising tool to investigate melanoma development and as a preclinical model for drug discovery.

In Model, In Vitro and In Vivo Killing Efficacy of Antitumor Peptide RDP22 on MUG-Mel2, a Patient Derived Cell Line of an Aggressive Melanoma Metastasis

“…Melanoma organotypic models were generated according to a previously published protocol [ 19 ]. Briefly, 5 × 105 keratinocytes at passage 3 were mixed with a pre-defined ratio of melanoma cells in E2 medium (E1 medium supplemented with 1.44 mM CaCl2) and seeded on a polycarbonate membrane (pore size 0.4 µm) with 12-well inserts (Greiner Bio-One, Frickenhausen, Germany).…”

“…For enhanced output of in vitro experiments, before in vivo studies, a number of 3D studies were applied such as tumor spheroids and second organotypic melanoma models. Accrued advantages of the latter such as the recently published mOS-REp [ 19 ] are traced back to the fact that these 3D models bridge the gap between the simplicity of 2D cell culture or spheroids lacking a microenvironment and the complexity of full-thickness skin equivalents and animal models [ 20 , 21 ]. The models in which the tumors mature within a physiologically differentiated epidermis enable the investigation of melanomagenesis, melanoma treatment and cellular or molecular crosstalk between the tumor and its surrounding skin cells.…”