HIF1A and colorectal carcinoma: Noteworthy, a treatment of the CRC cells with the chemotherapeutic agent 5-FU was ineffective in preventing HIF-1α expression, but the combined administration of 5-FU and resveratrol led to a down-regulation of HIF-1α, thus appearing HIF-1α to be a target of resveratrol but not of 5-FU (Figure 4A).