Crosstalk between TF/FVIIa and EGFR signaling in colorectal cancer cells.

TF/FVIIa (Tissue Factor/Active Coagulation factor VII) and EGFR (Epidermal Growth Factor Receptor) signaling both promote malignant progression of colorectal cancer. However, the crosstalk of these two signaling pathways in human colorectal cancer cells remains unclear. Here we detected the changes of mRNA profile in human colorectal cancer cell SW620 exposed to FVIIa. Microarray showed that mRNA levels of EGFR ligands were significantly upregulated. Western blot analysis confirmed the upregulation of EGFR ligands and the phosphorylation of EGFR at tyrosine-845 in colorectal cancer cells exposed to FVIIa. However, knockdown of TF by RNAi could block the upregulation of EGFR ligands induced by FVIIa stimulation. On the other hand, the expression of components of TF/FVIIa signaling was significantly upregulated in LoVo cells stimulated by EGF. However, the crosstalk between the two signaling pathways could not be detected in HT-29 colon cancer cells bearing wild-type KRAS. Taken together, our study suggest that the crosstalk between TF/FVIIa and EGFR signaling pathways in colon cancer cells depends on KRAS mutation.