CD44 and breast carcinoma: On the other hand, E-cadherin participates in the negative regulation of CD44 expression and functional activity, because the increasing E-cadherin level in PC3 prostate cancer cells leads to a decrease in the amount of CD44 protein, and murine mammary carcinoma TA3 cells overexpressing E-cadherin display weakness in CD44-dependent binding with hyaluronic acid accompanied by a reduction in cell invasiveness [63,64].