CEMIP2 and cancer: The transmembrane protein TMEM2 is a major cell-surface hyaluronidase that degrades HMW HA into low-molecular weight (LMW) ~5 kDa fragments.4–6 Notably, TMEM2’s cleavage activity is specific to non-sulfated HA and does not cleave other sulfated GAGs.4 Besides degradation caused by pathogen-derived external hyaluronidases, accelerated degradation of HA is found in other pathologic conditions including rheumatoid arthritis, diabetes, cancer, and inflammation,3,7 possibly caused by altered cellular HA metabolism.