MPO and gastric neoplasm: In our mouse model, the number of pro-inflammatory cell types was significantly increased (i.e., leukocyte infiltration), as observed by the numbers of activated macrophages (F4/80 positive) and neutrophils (myeloperoxidases, MPO) in mice exhibiting gastric tumors (0.746 ± 0.041 and 0.721 ± 0.064, respectively), compared to untreated mice or mice treated with only capsaicin or H. pylori (p < 0.0001; Figure S4a–b).