Given that, the levels of IL-34 are high in the sera of patients with endometriosis and any further stimulation with IL-34 resulted in the up-regulation of CSF1R, p-JAK3, p-STAT6, VEGF, MMP-2, and MMP-9 in eutopic endometrial stromal cells, could lead us to the conclusion that the preconditions for neurogenesis under the disease exist [79]. Here, MMP9 is linked to endometriosis.