Development and characteristics of a human cell assay for screening agents for melanoma prevention

ArticleinMelanoma Research 17(1):42-50 · March 2007with9 Reads
Impact Factor: 2.28 · DOI: 10.1097/CMR.0b013e3280142f96 · Source: PubMed

This paper describes the development and initial evaluation of a human cell assay to identify potentially efficacious agents for preventing melanoma. Four human cell lines were used: normal melanocytes, a radial growth-phase-like melanoma cell line (WM3211), a vertical growth-phase-like melanoma cell line (Lu1205), and 83-2c, a cell strain cloned from metastatic melanoma. Four endpoints were evaluated in ultraviolet B-treated cells: annexin V, human leukocyte antigen-DR; E-cadherin, and N-cadherin. Annexin V was induced by nimesulide, 4-hydroxyphenylretinamide, and difluoromethylornithine in ultraviolet-B-treated radial growth-phase-like melanoma cells. None of the agents inhibited human leukocyte antigen-DR expression in ultraviolet-B-treated radial growth-phase-like melanoma cells, the only cells that strongly expressed human leukocyte antigen-DR. E-cadherin was overexpressed only in radial growth-phase-like melanoma cells relative to melanocytes, and ultraviolet B exposure dramatically reduced this expression. E-cadherin was only induced by difluoromethylornithine in ultraviolet-B-treated radial growth-phase-like melanoma cells. N-cadherin was over- expressed in all melanoma cell lines relative to melanocytes. In this study, all candidate preventive agents inhibited N-cadherin in ultraviolet B-treated radial growth-phase-like melanoma cells. Four agents inhibited N-cadherin in ultraviolet B-treated vertical growth-phase-like melanoma cells. The mean ratios of N-cadherin to E-cadherin levels and specific endpoint responses for both the radial growth-phase-like melanoma and vertical growth-phase-like melanoma cells were used to rank the agents. Agents were evaluated at clinically relevant concentrations. The rankings were difluoromethylornithine>4-hydroxyphenylretinamide>nimesulide>9-cis-retinoic acid>polyphenon E. Diphenylhydramine, D-mannitol, and nordihydroguaiaretic acid were inactive. The results of these initial studies suggest that ultraviolet-B-treated radial growth-phase-like melanoma cells are the most responsive to chemopreventive agents, and may be the cell line of choice for screening melanoma prevention agents.

    • "The markers used for these studies were N-cadherin and P-cadherin. Both 4-HPR and 9-cis retinoic acid had some effects on reversing the changes in marker expression after ultraviolet (UV)-B radiation of the cells [81] . It is not clear whether the chosen markers are specific for retinoid chemoprevention activity in melanoma. "
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