KRAS and small intestine adenocarcinoma: Based on these findings, we hypothesized that the KRAS mutation status and HES-1 expression may be associated with tumor location in small intestinal adenocarcinomas, and Notch-independent HES-1 expression may be linked to mutated KRAS. In this study, we found that the survival rates of patients with KRASMT were significantly reduced only in the loss of HES-1 expression (HES-1Loss/KRASWT and HES-1Loss/KRASMT, P = 0.001), while the survival rate of patients with HES-1Intact tumors was not dependent on KRAS mutation status (HES-1Intact/KRASWT and HES-1Intact/KRASMT, P = 0.252) (Figure 4).