Department of Pharmacy, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, People's Republic of China.
Department of Pharmacy, College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, People's Republic of China.
Life Sci. 2021 Feb 1;266:118886. doi: 10.1016/j.lfs.2020.118886. Epub 2020 Dec 10.
Triple negative breast cancer (TNBC) has drawn more and more attention due to its high mitotic indices, high metastatic rate and poor prognosis. Gene therapy, especially RNA interference (RNAi), has become a promising targeted therapy. However, improvement of transfection efficiency and discovery of target genes are major problems for the delivery of small interfering RNAs (siRNA).
In the present study, we developed GALA- and CREKA-modified PEG-SS-PEI to deliver siRNAs targeting on EGFR and BRD4 for TNBC therapy. The PEG-SS-PEI/siRNA complexes were prepared by electrostatic interaction and characterized by dynamic light scattering (DLS) and transmission electron microscope (TEM). The release characteristic, stability, cellular uptake and intracellular localization of the complexes were also studied. The effect of the complexes on cell viability was measured in MDA-MB-231 and HUVEC cells. The in vitro anti-tumor activities of the complexes were analyzed by Transwell invasion assay and wound healing assay. The gene silencing effect was evaluated by quantitative real time-polymerase chain reaction (qRT-PCR) and western blot.
The results revealed that the GALA- and CREKA-modified PEG-SS-PEI/siRNA complexes showed excellent transfection efficiency with redox-sensitive release profile and good biological compatibility. The complexes protected siRNA from the degradation of RNA enzymes. The complexes significantly inhibited the proliferation, invasion and migration of MDA-MB-231 cells via the synergistic inhibition of EGFR/PI3K/Akt and BRD4/c-Myc pathways.
Taken together, co-delivery of siEGFR and siBRD4 by GALA-PEG-SS-PEI and CREKA-PEG-SS-PEI may provide a more effective strategy for the treatment of TNBC.
由于三阴性乳腺癌（TNBC）具有较高的有丝分裂指数、较高的转移率和较差的预后，因此越来越受到关注。基因治疗，特别是 RNA 干扰（RNAi），已成为一种很有前途的靶向治疗方法。然而，提高转染效率和发现靶基因是小干扰 RNA（siRNA）传递的主要问题。
本研究中，我们开发了 GALA 和 CREKA 修饰的 PEG-SS-PEI 来递送针对 EGFR 和 BRD4 的 siRNA 用于 TNBC 治疗。通过静电相互作用制备 PEG-SS-PEI/siRNA 复合物，并通过动态光散射（DLS）和透射电子显微镜（TEM）进行表征。还研究了复合物的释放特性、稳定性、细胞摄取和细胞内定位。在 MDA-MB-231 和 HUVEC 细胞中测量复合物对细胞活力的影响。通过 Transwell 侵袭实验和划痕愈合实验分析复合物的体外抗肿瘤活性。通过定量实时聚合酶链反应（qRT-PCR）和 Western blot 评估基因沉默效果。
结果表明，GALA 和 CREKA 修饰的 PEG-SS-PEI/siRNA 复合物具有出色的转染效率，具有氧化还原敏感的释放特性和良好的生物相容性。复合物保护 siRNA 免受 RNA 酶的降解。复合物通过协同抑制 EGFR/PI3K/Akt 和 BRD4/c-Myc 通路，显著抑制 MDA-MB-231 细胞的增殖、侵袭和迁移。
总之，GALA-PEG-SS-PEI 和 CREKA-PEG-SS-PEI 共递送 siEGFR 和 siBRD4 可能为 TNBC 的治疗提供更有效的策略。
