According to TCGA data (GEPIA2), three distinct groups can be characterized by their CD44 isoform expression pattern: 1) cancers expressing CD44 isoforms 1-4 and consequently variant exons v2-v10, 2) cancers expressing CD44 isoforms 2-4 and variant exons v3-v10, and 3) cancers expressing only CD44 isoforms 3–4 (variant exons v8-v10). The gene discussed is CD44; the disease is cancer.