In cell-conditioned medium of cortical neurons, KLK6 activated matrix metalloproteinase 2 (MMP2) and a disintegrin and metalloproteinase with thrombospondin motif 19 (ADAMTS19), all members of the proteolytic and regulatory network in neurological disorders, triggering α-synuclein processing [45]. The gene discussed is KLK6; the disease is nervous system disorder.