ABSTRACT
OBJECTIVE AND DESIGN: This study was conducted to determine if differences in histidine decarboxylase expression and histamine levels exist between B16F10 melanoma cells and non-cancerous Melan-A melanocytes. METHODS: Immunofluorescence and western blot analysis were used to detect and compare histidine decarboxylase protein levels. Enzyme-linked immunoassay was used to detect, measure, and compare histamine levels. RESULTS: Histidine decarboxylase expression was found to be elevated in the B16F10 cells. Western blot analysis demonstrated levels of histidine decarboxylase protein expression more than twofold higher (p < 0.001) in B16F10 than in Melan-A cells. Histamine levels were 280-fold higher (p < 0.001) in B16F10 (229 ± 15 pg/mg protein) than in Melan-A (0.83 ± 0.03 pg/mg protein) cells. CONCLUSION: Results indicate an up-regulated histaminergic system in the B16F10 melanoma cells when compared to non-cancerous melanocytes. This supports the use of B16F10 cells as a model in which to investigate a potential role of the endogenous histaminergic system in regulating malignant cell function.
