ANXA2 and glioma: Under serum deprivation stress, S100A13 is extracellularly released from C6 glioma cells, but ANXA2 remains in the cell in the immunoblot analysis; however, there is a tight interaction between both proteins in the cytosol of C6 glioma cells in the presence of p40 Syt-1 and Ca2+ in the ELISA-based protein-binding assay [11].