ABSTRACT
The aim was to determine whether ultrasound targeted microbubble destruction (UTMD) promotes dual targeting of HSP72 and HSC70 for therapy of castration-resistant prostate cancer (CRPC), to improve the specific and efficient delivery of siRNA, to induce tumor cell specific apoptosis, and to find new therapeutic targets specific of CRPC.VCaP cells were transfected with siRNA oligonucleotides. HSP70, HSP90 and cleaved caspase-3 expression were determined by real-time quantitative polymerase chain reaction and Western blotting. Apoptosis and transfection efficiency were assessed by flow cytometry. Cell viability assays were used to evaluate safety. We found HSP72, HSC70 and HSP90 expression to be absent or weak in normal prostate epithelial cells (RWPE-1), but uniformly strong in prostate cancerous cells (VCaP). UTMD combined with dual targeting of HSP72 and HSC70 siRNA improve the efficiency of transfection, cell uptake of siRNA, downregulation of HSP70 and HSP90 expression in VCaP cells at the mRNA and protein level, and induction of extensive tumor-specific apoptosis. Cell counting kit-8 assays showed decreased cellular viability in the HSP72/HSC70-siRNA silenced group. These results suggest that the combination of UTMD with dual targeting HSP70 therapy for PCa may be most efficacious, providng a novel, reliable, non-invasive, safe targeted approach to improve the specific and efficient delivery of siRNA, and achieve maximal effects.
Subject(s)
HSC70 Heat-Shock Proteins/genetics , HSP72 Heat-Shock Proteins/genetics , HSP90 Heat-Shock Proteins/genetics , Prostatic Neoplasms, Castration-Resistant/genetics , Apoptosis/genetics , Caspase 3/biosynthesis , Caspase 3/metabolism , Cell Line, Tumor , Cell Proliferation , Cell Survival , Down-Regulation , Genetic Therapy , HSC70 Heat-Shock Proteins/biosynthesis , HSP72 Heat-Shock Proteins/biosynthesis , HSP90 Heat-Shock Proteins/biosynthesis , Humans , Male , Microbubbles , Prostatic Neoplasms, Castration-Resistant/diagnostic imaging , Prostatic Neoplasms, Castration-Resistant/therapy , RNA Interference , RNA, Small Interfering , Transfection , UltrasonographyABSTRACT
Gene therapy is a potentially viable approach for treating hormone-refractory prostate cancer (HRPC), it requires efficient delivery systems and a target gene. Inducing carcinoma cell apoptosis by inhibition of heat shock protein 70 (HSP70) overexpression has been emerging as an attractive strategy for cancer therapy. In our study, the high tumor-specificity of human telomerase reverse transcriptase (HTERT) expression prompted the use of an HTERT/cytomegalovirus (CMV) chimeric promoter to drive HSP70-ShRNA expression to induce HRPC 22RV1 cell apoptosis. At the same time, sonoporation induced by ultrasound-targeted microbubble destruction (UTMD) was utilized for delivery of plasmid loaded with HTERT/CMV promoter. Our results indicated the combination of sonoporation, low-dose liposomes and HTERT/CMV chimeric promoter as a delivery system has the potential to promote efficient gene transfer with lower cytotoxicity.
Subject(s)
Genetic Therapy , HSP70 Heat-Shock Proteins/genetics , Prostatic Neoplasms/genetics , Transfection/methods , Apoptosis , Cell Line, Tumor , Cytomegalovirus/genetics , Gene Expression Regulation, Neoplastic , Genetic Vectors , Humans , Liposomes/administration & dosage , Male , Promoter Regions, Genetic , Prostatic Neoplasms/pathology , Prostatic Neoplasms/therapy , RNA, Small Interfering , Telomerase/geneticsABSTRACT
The nano-microcapsules drug delivery system is currently a promising method for the treatment of many types of diseases, particularly tumors. However, the drug delivery efficiency does not reach a satisfactory level to meet treatment demands. Therefore, the effectiveness of delivery needs to be improved. Based on the alterations in the structure and modification of nano-microcapsules, ultrasound-targeted microbubble destruction (UTMD), a safe physical targeted method, may increase tissue penetration and cell membrane permeability, aiding the drug-loaded nano-microcapsules ingress the interior of targeted tissues and cells. The effectiveness and exact mechanism of action of the drug-loaded nano-microcapsules delivery system mediated by UTMD have yet to be fully elucidated. In this study, the latest advancement in UTMD-mediated drug loaded nano-microcapsules system technology was reviewed and the hindrances of UTMD-mediated drug delivery were assessed, in combination with a prospective study. The findings suggested that the drug delivery efficiency of nano-microcapsules mediated by UTMD was distinctly improved. Thus, the UTMD-mediated drug-loaded nano-microcapsules delivery system may significantly improve the efficiency of drug delivery, which may be a promising new therapeutic method.
