CD44 and breast cancer: Targeting TGFβ appears particularly attractive, as TGFβ stimulates desmoplastic collagen and HA deposition.[61] In fact, in murine breast carcinoma models, TGFβ blocking was found to decrease collagen I content in the tumor stroma and increase vascular perfusion, thus improving drug delivery.[62] We additionally show that preventing HA binding by blocking CD44 can also normalize the tumor microenvironment and restore drug delivery, as observed in our models of advanced, aggressive breast cancer (MDA‐MB‐468 MVNs), which also expressed the highest level of CD44 (Figure 4).