We then analyzed the correlation between lncRNA KB-1980E6.3 and the hypoxia-responsive genes in breast cancer tissues from The Cancer Genome Atlas (TCGA) and found that lncRNA KB-1980E6.3 was positively correlated with VEGFA (r = 0.4593, P < 0.001), SLC2A1 (r = 0.4182, P < 0.001), P4HA1 (r = 0.4341, P < 0.001), and CA9 (r = 0.5421, P < 0.001) (Fig. S1c), the known targets of HIF in breast cancer. The gene discussed is CA9; the disease is breast cancer.