Figure 6: In vivo tumour-targeting efficiency of CaP-rHDL and its macropinocytosis dependence.

(a) In vivo real-time NIR fluorescent imaging of the mice bearing intracranial C6 glioblastoma at 4, 8, 12 and 24 h after i.v. injected with DiR-labelled CaP-LNC (DiR-CaP-LNC) and CaP-rHDL (DiR-CaP-rHDL). (b) Distribution of DiR-CaP-LNC and DiR-CaP-rHDL at 24 h post-injection in the organs of the mice bearing intracranial C6 glioblastoma. (c) Qualitative and (d) semi-quantitative analysis of the tumour accumulation of DiR-CaP-LNC and DiR-CaP-rHDL at 3 h post-injection in the mice bearing intracranial C6 glioblastoma after the pretreatment with EIPA (30 μg g⁻¹ body weight, i.p.) or vehicle only. (e) Brain distribution of DiI-CaP-LNC and DiI-CaP-rHDL at 3 h post-injection in the mice bearing intracranial C6 glioblastoma after the pretreatment with EIPA (30 μg g⁻¹ body weight, i.p.) or vehicle only. Red lines showed the boundary between glioblastoma and normal brain tissue. Arrows indicate the glioblastoma zones. Scale bar, 100 μm. (f) Qualitative and (g) semi-quantitative analysis of the tumour accumulation of Cy5-CaP-LNC-PEG and Cy5-CaP-rHDL at 3 h post-injection in the mice bearing GICs-derived glioblastoma after the pretreatment with EIPA (30 μg g⁻¹ body weight, i.p.) or vehicle only. (h) Brain distribution of Cy5-CaP-LNC-PEG and Cy5-CaP-rHDL at 3 h post-injection in the mice bearing GICs-derived glioblastoma after the pretreatment with EIPA (30 μg g⁻¹ body weight, i.p.) or vehicle only. Scale bar, 100 μm. For d and g, data represent mean±s.d. (n=3). The significance of the differences (*P<0.05, ***P<0.001) was evaluated by two-tailed Student’s t-test.