Fas Ligand Reduces Viability in Primary Melanoma Short-Term Cell Cultures More than in Metastatic Melanoma Short-Term Cell Cultures

BACKGROUND: Apoptotic pathway aberrations are reported as important tumor progression factors in melanoma. OBJECTIVE: Effect of soluble Fas ligand (sFasL) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) on short-term cultured melanoma cell viability from different stages of melanoma. RESULTS: Recombinant human FasL reduced viability after 18 h in a dose-dependent manner in 4 of 5 cell cultures from primary tumors and 1 of 9 cell cultures from metastatic melanoma (67.5 vs. 96.4%, p = 0.007). DNA fragmentation on flow cytometry confirmed apoptosis. Incubation with TRAIL had no effect on melanoma cell viability. Immunohistochemistry showed Fas in 3 of 4 primary and in 6 of 7 metastatic lesions, no FasL in primary lesions, and FasL in 5 of 7 metastatic lesions. CONCLUSION: Melanoma short-term cell cultures from primary tumors show decreased viability under FasL, but not TRAIL stimulation rather than short-term cell cultures derived from metastases.