Antitumor activity of integrin αVβ3 antibody conjugated-cationic microbubbles in liver cancer

Jiale Li, Ping Zhou, Hongbo Xu, Shuangming Tian, Wengang Liu, Yongfeng Zhao, Zheyu Hu


Background: The overexpression of integrin αVβ3 in hepatocarcinoma (HCC) promotes tumor progression, metastasis, and clinical staging. Thus, the inhibition of integrin αVβ3 might be potentially effective as an anti-cancer agent in HCC.
Methods: In this study, we aimed to investigate the antitumor effect of integrin αVβ3 antibody conjugated cationic microbubbles (CMBs) in HCC model. By conjugating with integrin αVβ3 antibody with non-targeting CMBs, CMBsαvβ3 was constructed. The antitumor effect of CMBsαvβ3 was evaluated in HepG2 cells in vitro and in HepG2 xenograft mice models. Bcl-2, p53 and CD31 mRNA level, and caspase-3 activity were examined in xenograft tumors. Cell proliferation assay and scratch test were performed to evaluate the anti-migrant effect of CMBsαvβ3 in vitro.
Results: CMBsαvβ3 could specifically target to HCC HepG2 cells and improve pEGFP-KDRP-CD/TK plasmid transfection efficiency. In HepG2 xenograft mice models, CMBsαvβ3 treatment significantly suppressed tumor weights and volumes. CMBsαvβ3 treatment suppressed Bcl-2 and p53 mRNA level in tumors. In HepG2 cells, CMBsαvβ3 significantly impaired wound healing and inhibited cell proliferation. Moreover, when combined with CD/TK double suicide gene transfection and 5-FC/GCV treatment, caspase-3 was activated and the cell proliferation was tremendously inhibited.
Conclusions: CMBsαvβ3 not only suppresses cell migration and proliferation, but also facilitates 5-FC/GCV plus CD/TK double suicide gene-induced apoptotic cell death. CMBsαvβ3 is a promising gene delivery agent with potential anti-tumor activity itself.