HMMR and carcinoma: Some studies have shown that hyaluronan of different molecular weights can be covalently attached to the surface of nanoparticles to engage the activity of targeted hyaluronan receptors (CD44 and CD168), which are used in various carcinoma cells (e.g., ovarian, colon, and stomach) or innate immune cells (e.g., macrophages) [42,43,44].