PPIA and neoplasm: While not previously associated with astrocytes, peroxiredoxin‐1 (PRDX1) is an intracellular enzyme with antioxidant activity reported to be secreted by tumor cells (Chang et al., 2005, 2006); and prolyl isomerase (PPIA), although cytoplasmic, is secreted as a defense mechanism in response to oxidative stress (Nigro et al., 2013).