On the other hand, in the CD44-positive prostate cancer cells (Figure 9, lower panels), large nanoparticle aggregates are accumulating at the cell membrane of cells treated with HA(200)Au samples (see, for instance, the open arrow in Figure 9b) and even larger aggregates are visible for those treated with HA(700)Au samples (Figure 9c, solid arrow). This evidence concerns the gene CD44 and prostate cancer.