The transfection efficiency and the targeted cellular uptake of HA/FA/PPD, FA/PPD and PPD were evaluated on CD44-positive and FR-positive B16 cells by fluorescence microscope and flow cytometry, respectively [20,21], while the co-delivery efficiency of PTX and pDNA into the same tumor cell was evaluated on CD44-positive and FR-negative HepG2 cells [22,23]. The gene discussed is CD44; the disease is neoplasm.