A number of Cdh1-cleaving host proteases are known, including matrix metalloproteases (e.g., MMP-3, MMP-7, or MMP-9), A Disintegrin and metalloproteinase domain-containing (ADAM) proteins (e.g., ADAM-10 and ADAM-15), kallikreins, and further, which are often upregulated or constitutively activated in H. pylori-associated gastritis and tumors [27]. This evidence concerns the gene KLK4 and gastritis.