CA9 and cancer: In this case, vanillin dramatically down-regulates HIF-1α promoter activity (Figure 5A) and its target genes involved in glycolytic metabolism (CA-IX, PDK1, GLUT1, and LDHA: carbonic anhydrase 9, pyruvate dehydrogenase kinase 1, glucose transporter 1, and lactate dehydrogenase A) and cancer metastasis (FN1, LOXL2, and uPAR) under hypoxia in A2058 and A375 cells (Figure 5B,C).