HIF1A and neoplasm: RNA-sequencing analyses identified Car9 as a HIF-1α specific target gene (Supplementary Fig. 3c) and the protein product of this gene, CA9, showed membrane staining in tumours from Vhl∆/∆Trp53∆/∆Rb1∆/∆ and Vhl∆/∆Trp53∆/∆Rb1∆/∆Hif2a∆/∆ mice but not in tumours from Vhl∆/∆Trp53∆/∆Rb1∆/∆Hif1a∆/∆ mice (Fig. 1d).