Expression of activated forms AKT, MEK, mTOR, p70 and STAT3 in the GI tumor cells used in this study each showed a significant partial protection of cells from [curcumin + sildenafil] induced cell death, abolishing the cell-death potentiating effect of sildenafil (Figure 8D; Supplementary Figure 11B). The gene discussed is STAT3; the disease is digestive system neoplasm.