CA9 and breast cancer: Urquidi et al. carried out the combination of three different gene signatures [32,132,133] together with 6 other independent genes from different biomarker studies, after which they stablished a new diagnostic gene signature based on detected expression of 18 mRNAs (ANXA10, BIRC5, CA9, CCL18, CDK1, CTSE, DSC2, IGF2, KFL9, KRT20, MDK, MMP1, MMP9, MMP10, MMP12, RAB1A, SEMA3D and SNAI2) in urine samples from BC patients, achieving 85% sensitivity and 88% specificity (AUC = 0.935) [134].