S100A13 and central nervous system cancer: Fluorescence microscopic analysis detected both immunoreactive (ir)S100A13 and irANXA2 in permeabilized C6 glioma cells in the presence of serum, as shown in Figure 2B. irANXA2 and irS100A13 were not detected in the absence of permeabilization, indicating that both proteins were present inside the cell.