TCF4 and cancer: Briefly, in normoxic conditions COX-2/PGE2 axis promotes the stimulation of β-Catenin/TCF-4 activity whereas during hypoxia, a common status occurring in the advanced stage of cancer, β-Catenin, displaced from TCF-4, interacts with HIF-1, improves its transcriptional activity and substantially increases the expression of HIF-1 targets such as VEGF60.