Development and characteristics of a human cell assay for screening agents for melanoma prevention.
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.
Elmore
Eugene
E
Department of Radiation Oncology, University of California, Irvine, California 92697-2695, USA. eelmore@uci.edu
Jain
Aarti
A
Siddiqui
Shazia
S
Tohidian
Nilou
N
Meyskens
Frank L
FL
Steele
Vernon E
VE
Redpath
John L
JL
D017304:Annexin A5 / Q000032:analysis; D015820:Cadherins / Q000032:analysis; D002460:Cell Line; D045744:Cell Line, Tumor; D052816:Foreskin / Q000166:cytology; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D008403:Mass Screening / Q000379:methods; D008544:Melanocytes / Q000166:cytology* / Q000473:pathology; D008545:Melanoma / Q000453:epidemiology / Q000517:prevention & control*; D015203:Reproducibility of Results; D012878:Skin Neoplasms / Q000453:epidemiology / Q000517:prevention & control*; D014466:Ultraviolet Rays
D017304:Annexin A5; D015820:Cadherins