PROTEOMIC ANALYSIS OF LASER MICRODISSECTED MELANOMA CELLS FROM SKIN ORGAN CULTURES.

Gaining insights into the molecular events that govern the progression from melanoma in situ to advanced melanoma and understanding how the local microenvironment at the melanoma site influences this progression are two clinically pivotal aspects that to date are largely unexplored. In an effort to identify key regulators of the crosstalk between melanoma cells and the melanoma-skin microenvironment, primary andmetastatic human melanoma cells were seeded into skin organ cultures (SOCs) and grown for two weeks. Melanoma cells were recovered from SOCs by laser microdissection and whole-cell tryptic digests were analyzed by nanoflow liquid chromatography-tandem mass spectrometry. The differential protein abundances were calculated by spectral counting, the results of which provides evidence that cell-matrix and cell-adhesion molecules that are upregulated in the presence of these melanoma cells recapitulate proteomic data obtained from comparative analysis of human biopsies of invasive melanoma and a tissue sample of adjacent, noninvolved skin. This concordance demonstrates the value of SOCs for conducting proteomic investigations of the melanoma microenvironment.

Collagen 1, Cytokeratin 14, Cytokeratin 16, Cytokeratin 17, Cytokeratin 5, Cytokeratin 6A, EFT-400, EpiDerm full-thickness 400, Fibronectin, Intraepidermal injection, Laser microdissection, Melanoma, Melanomas in the vertical growth phase, Metastatic growth phase (MGP), Nanoflow liquid chromatography-tandem mass spectrometry, Plectin, Radial growth phase, Tenascin-C, Tenascin-D, Thrombospondin-1, Transgelin 2, WM1158, WM983-A, á-Actinin-4

WM1158 (MGP) Melanoma cell line, WM983-A (VGP) Melanoma cell line