While downstream signals activated by LYVE1 as a hyaluronan receptor on LECs are not well characterized, LYVE1 is a homolog of CD44, which is also hyaluronan receptor known to activate lymphocytes, direct circulation of lymphocytes, and aid in tumorigenesis and lymph node metastasis in breast cancer [35–39]; thus, LYVE1 may serve a similar function as CD44 in LECs. This evidence concerns the gene CD44 and breast cancer.