Because distinct progenitor stem cells lower in a stem cell hierarchy have a decreased capacity to express stemness properties, it is conceivable that a CSC biomarker (e.g., BAP1) will identify a tumor subtype (e.g., ccRCC4) that is clinically fulminant compared with a non-CSC biomarker (e.g., VEGFR), which will recognize another tumor subtype (e.g., ccRCC3) that is clinically indolent [31,32,33]. This evidence concerns the gene KDR and neoplasm.