Shan Liu

Background The inhibition of angiogenesis leads to the degeneration of tumors; thus, anti-angiogenesis therapy is a strategy for the treatment of tumors. Accumulating documents has demonstrated effective anti-angiogenic strategies should simultaneously inhibit endothelium-dependent vessels (EDV) and tumor cell-mediated vasculogenic mimicry (VM). Although cRGD peptide enabling to bind with α_vβ₃ integrin can specifically inhibit both EDV and VM, however peptide-based drug delivery platforms have not obtained the expected therapeutic efficacy due to their rapid degradation and low tumor accumulation. Results Herein, we developed cRGD nanoparticles (cRGD Nano) loaded microbubbles (MB) to enhance their anti-EDV and anti-VM ability for endothelial cells and ovarian cancer cells due to the sonoporation effect from ultrasound (US). Heparin as backbone conjugated with cRGD to prepare cRGD-H conjugate and then loaded with biotin thereby following dialysis to fabricate cRGD Nano. Subsequently, the cRGD Nano were incorporated with MB via avidin-biotin linkage to fabricate cRGD Nano-MB. The enhanced anti-angiogenic effect can take profit of cRGD from cRGD Nano and sonoporation effect from US combined with MB. cRGD Nano has been characterized, and cRGD Nano-MB combined with US exhibited the best intracellular uptake ability than cRGD Nano and cRGD Nano-MB without US by flow cytometry and confocal laser scanning microscopy. Also, cRGD Nano-MB combined with US could efficiently discourage the tube formation of endothelial cells and cancer cells, and presented excellent significant anti-proliferation activity in vivo. Conclusions The combination of cRGD Nano-MB and US is expected to be a promising strategy for peptide drug delivery and enhancing anti-proliferation and anti-angiogenesis.