CAIX is regulated by the Von Hippel Lindau (VHL) protein (pVHL) [44] and serves as a hallmark for multiple solid tumors [45], including RCC [46], HNSCC [47], glioblastoma [48], breast cancer [49], mesothelioma [50], and bladder cancer [51]. The gene discussed is CA9; the disease is renal cell carcinoma.