The present summary shows that the changes in the cell density of MDSCs, Tregs, and M2 macrophages have been found in the most pathogen infection, except for Campylobacter jejuni (Supplementary Table 1), suggesting that the most oral-gut pathogens may help pancreatic cancer escape from host immune by affecting immune suppressive cells via miR-21 and PTEN axis. This evidence concerns the gene PTEN and familial pancreatic carcinoma.