SPP1 and aneurysm: Among the experimental biomarkers, amino-terminal propeptide of type III procollagen (PIIINP) [26], tissue-type plasminogen activator (tPA) [27,29,40], osteopontin [34], haptoglobin polymorphism [30], IGF I and II [33], thioredoxin (TRX) [31], neutrophil extracellular traps (NETs) [41], and genetic factors, as polymorphisms [35] and micro RNAs [36] were positively associated with aneurysm expansion.