Changes in the expression levels of CagA and Cag-signaling molecules in serial tumor cells before and after completion of HPE (A) A high baseline expression of CagA in case #1 tumor cells. (B) A high baseline expression of p-SHP-2 in case #1 tumor cells. (C) A high baseline expression of p-ERK in case #1 tumor cells. (D) CagA expression was no longer detectable in remitting tumor cells 1 month after completion of HPE (case #1, the time to CR after completion of HPE was 4 month). Immunohistochemical staining showed no expression of p-SHP-2 (E) and p-ERK (F) in remitting tumor cells 1 month after completion of HPE (case #1). (G) High baseline expression of CagA in case #3 tumor cells. (H) A high baseline expression of p-SHP-2 in case #3 tumor cells. (I) A high baseline expression of p-ERK in case #3 tumor cells. (J) Decreased expression of CagA in tumor cells that achieved partial remission 4 months after completion of HPE (case #3, the time to CR after completion of HPE was 10 months). Immunohistochemical staining showed decreased expression of p-SHP-2 (K) and p-ERK (L) in tumor cells that achieved partial remission 4 months after completion of HPE (case #3). All immunohistochemical images were viewed at ×400.