RAF1 and malignant colon neoplasm: To further confirm the involvement of PI3K-Akt and RAF-MEK-ERK signaling pathways in the synergistic anti-tumor efficacy caused by the combined usage of Aspirin and Cisplatin, LY294002, a widely used pan-PI3K inhibitor [22], and U0126, a potent small molecule MEK1/2-selective inhibitor [23] was respectively used to combine with Aspirin and Cisplatin to co-treat colon cancer cells.