Circulating melanoma cells as a potential biomarker to detect metastasis and evaluate prognosis.

TNM staging is mainly used to evaluate the prognosis of melanoma patients. Serum biomarkers such as 5-S-cysteinyldopa (5-S-CD) have occasionally been used but most do not respond until the tumour burden becomes high. Recently, circulating melanoma cells (CMC) have been reported as a possible new biomarker to detect metastasis, monitor treatment response and predict prognosis.

Diacylglycerol kinase alpha suppresses tumor necrosis factor-alpha-induced apoptosis of human melanoma cells through NF-kappaB activation.

We investigated the implication of diacylglycerol kinase (DGK) alpha (type I isoform) in melanoma cells because we found that this DGK isoform was expressed in several human melanoma cell lines but not in noncancerous melanocytes. Intriguingly, the overexpression of wild-type (WT) DGKalpha, but not of its kinase-dead (KD) mutant, markedly suppressed tumor necrosis factor (TNF)-alpha-induced apoptosis of AKI human melanoma cells. In the reverse experiment, siRNA-mediated knockdown of DGKalpha significantly enhanced the apoptosis.