AQ4N with its high penetrating property can spread deeply into the tumor tissue for enhanced drug exposure and killing of the hypoxic tumor cells in the inner region.44 Moreover, it showed that HIF‐1α expression in PC‐3 tumors treated with the targeted trimodal nanosystem (with siHIF‐1α) was remarkably suppressed to ≈20% level of that treated with the targeted nanosystem without siHIF‐1α (c(RGDfK)‐ppGO/VP‐AQ4N) (Figure 7B,C). This evidence concerns the gene HIF1A and neoplasm.