IL6R and cancer: ADAM substrates include many cancer-related proteins, such as Notch receptors and their ligands [3], epidermal growth factor receptor (EGFR) ligands [4, 5], interleukin-6 receptor (IL-6R) [6], tumor necrosis factor (TNF) and its receptors [7], E-cadherin [8], and CD44 [9].