Development of EphA2 siRNA-loaded lipid nanoparticles and combination with a small‐molecule histone demethylase inhibitor in prostate cancer cells and tumor spheroids

Abstract

Background siRNAs hold a great potential for cancer therapy, however, poor stability in body fluids and low cellular uptake limit their use in the clinic. To enhance the bioavailability of siRNAs in tumors, novel, safe, and effective carriers are needed. Results Here, we developed cationic solid lipid nanoparticles (cSLNs) to carry siRNAs targeting EphA2 receptor tyrosine kinase (siEphA2), which is overexpressed in many solid tumors including prostate cancer. Using DDAB cationic lipid instead of DOTMA reduced nanoparticle size and enhanced both cellular uptake and gene silencing in prostate cancer cells. DDAB-cSLN showed better cellular uptake efficiency with similar silencing compared to commercial transfection reagent (Dharmafect 2). After verifying the efficacy of siEphA2-loaded nanoparticles, we further evaluated a potential combination with a histone lysine demethylase inhibitor, JIB-04. Silencing EphA2 by siEphA2-loaded DDAB-cSLN did not affect the viability (2D or 3D culture), migration, nor clonogenicity of PC-3 cells alone. However, upon co-administration with JIB-04, there was a decrease in cellular responses. Furthermore, JIB-04 decreased EphA2 expression, and thus, silencing by siEphA2-loaded nanoparticles was further increased with co-treatment. Conclusions We have successfully developed a novel siRNA-loaded lipid nanoparticle for targeting EphA2. Moreover, preliminary results of the effects of JIB-04, alone and in combination with siEphA2, on prostate cancer cells and prostate cancer tumor spheroids were presented for the first time. Our delivery system provides high transfection efficiency and shows great promise for targeting other genes and cancer types in further in vitro and in vivo studies.

The significance of EphA2-regulated Wnt/β-catenin signal pathway in promoting the metastasis of HBV-related hepatocellular carcinoma

“…EphA2, which activates downstream signaling pathways in combination with its ligand EphrinA1, plays a crucial role in cell proliferation and cell transformation [10]. Recently, EphA2 has been found to be expressed at high level in tumor tissues and its overexpression is closely associated with the development of tumor cells [11][12][13]. Increasing evidence indicated that EphA2 may be a potential regulatory factor in the progression of HCC and EphA2 overexpression can lead to tumor angiogenesis, lymph node metastasis and satellite tumor lesions in HCC tissues [14,15].…”

Recent Advancements in the Design of Nanodelivery Systems of siRNA for Cancer Therapy

“…The linear PEI–siRNA conjugate was nonimmunogenic and cytocompatible. Also, PEGylated PEI/siRNA can be advanced using a copolymer/mixed polymer that is extra stable and its hydrophilic layer formed by PEG polymer coating outside the PEI/siRNA conjugate reduces NCs aggregation. , Similarly, instead of 1,2-di- O -octadecenyl-3-trimethylammonium propane (DOTMA), dimethyldioctadecylammonium bromide (DDAB) cationic lipid NCs are used to transfect siRNA, resulting in increased cellular uptake and excellent silencing properties when compared to commercially available transfection reagents (Dharmafect 2) . For example, polyamidoamine dendrimer NCs modified with methyl ether PEG and poly- l -lysine (PLL) improve tumor penetrability when paired with Polo-Like Kinase (PLK-1) siRNA.…”

An Overview of siRNA Delivery Strategies for Urological Cancers

“…It regulates cell proliferation, survival and differentiation; moreover, it is overexpressed in many cancers including PC [100]. Oner et al [88] employed cationic solid lipid nanoparticles (cSLNs) to deliver siRNAs targeting EphA2 (siEphA2). In PC3, DU145 (non-androgenresponsive PC cells) it was shown that cSLNs loaded with a fluorescent siRNA could transfect about 80% of the cells, turning out to be superior to a commercial transfection reagent.…”