Also, other correlations between cytokines are only in migraine patients without aura: between PAI-1 and sICAM-1 (inverse); between MMP-9 and sICAM-1 (inverse); and between TGF-α and PAI-1 (direct), MMP-9 (direct), and sICAM-1 (inverse). This evidence concerns the gene MMP9 and migraine disorder.