RAB11B and breast carcinoma: Although neither Rab11A nor Rab11B is required for PAR1 constitutive internalization, Rab11B siRNA-mediated knockdown decreased PAR1 cell surface expression by blocking PAR1 constitutive recycling to the cell surface, which resulted in enhanced PAR1 lysosomal sorting and degradation in endothelial cells and breast cancer cells [28].