Abstract
Besides playing a crucial role in immune surveillance, human leukocyte antigens (HLA) possess numerous non-immune functions involved in cell communication. In the present study, screening of a panel of HLA class I- and HLA class II-specific monoclonal antibodies (mAbs) for their effects on the metabolism of human melanoma cells showed for the first time that the HLA-B,C-specific mAb B1.23.2 reduced the expression level of key glycolytic enzymes, but did not affect that of mitochondrial respiration effectors. As a result, the metabolism of melanoma cells shifted from a Warburg metabolism to a more oxidative phosphorylation. In addition, the HLA-B,C-specific mAb B1.23.2 downregulated the expression of glutamine transporter and glutaminase enzyme participating in the reduction of tricarboxylic acid cycle. The HLA-B,C-specific mAb B1.23.2-mediated reduction in energy production was associated with a reduction of melanoma cell motility. On the whole, the described results suggest that HLA class I antigens, and in particular the gene products of HLA-B and C loci play a role in the motility of melanoma cells by regulating their metabolism.