[Growth inhibition of melanoma cells by interferons in vitro. Similar antiproliferative effects of 100-1000 times lower concentrations of nIFN-beta in comparison with rIFN-alpha-2a].
The type I interferons (IFNs) rIFN-alpha 2a and nIFN-beta showed a significant dose-dependent antiproliferative effect on melanoma cell monolayer cultures in vitro compared with untreated controls (P less than 0.01 at 10 IU/ml; P less than 0.01 and P less than 0.001 at 1,000 IU/ml). The antiproliferative effect of a single IFN dose lasted for a maximum of 4 days, after which uninhibited proliferation of melanoma cells was again observed. In all experiments nIFN-beta showed a similar antiproliferative effect to rIFN-alpha 2a on the two melanoma cell lines (StML-11, SKMel-28) tested, when used in concentrations 100-1,000 times lower. At concentrations of 10,000 IU/ml rIFN-alpha 2a and 100-1,000 IU/ml hIFN-beta cytotoxic effects were observed.