HIF1A and cancer: In this regard, although normal physiological HIF-1α responses in non-malignant cells can inhibit the activity of normal c-Myc, paradoxically, the deregulated expression of oncogenic c-Myc that exists in many cancers such as colorectal carcinoma works together with HIF-1α to confer the tumor metabolic phenotype described as the Warburg effect or aerobic glycolysis as well as to promote angiogenesis [14].