First, we injected AGS cells (1 × 107 cells) stably overexpressing KLK6 in nude mice and divided these into 3 groups that were treated with DMSO, 3-MA, AF alone, and AF plus 3-MA (Figure 7E and 7F) or DMSO, AF alone, and AF plus CQ (Figure 7G and 7H). Here, KLK6 is linked to atrial fibrillation.