title: Ultrasound-targeted microbubble destruction combined with dual targeting of HSP72 and HSC70 inhibits HSP90 function and induces extensive tumor-speciﬁc apoptosis.
abstract: The specific and efficient delivery of small interfering RNA (siRNA) into cancer cells in vivo remains a major obstacle. In this study, we investigated whether ultrasound-targeted microbubble destruction (UTMD) combined with dual targeting of HSP72 and HSC70 in prostate cancer cell lines improve the specific and efficient cell uptake of siRNA, inhibit HSP90 function and induce extensive tumor-speciﬁc apoptosis. VCaP cells were transfected with siRNA oligonucleotides. Cell viability assays were used to evaluate the safety of UTMD. The expression of HSP70, HSP90, caspase-8, caspase-3, PARP-1 and cleaved caspase-3 were determined by quantitative PCR and western blotting. Apoptosis and transfection efficiency were detected by flow cytometry. We found that HSP72, HSC70 and HSP90 expression was absent or weak in normal prostate epithelial cells (RWPE-1), and became uniformly and strongly expressed in prostate cancer cells (VCaP). VCaP and RWPE-1 cells expressed very low levels of caspase-8, caspase-3, PARP-1 and cleaved caspase-3. UTMD combined with dual targeting of HSP72 and HSC70 siRNA impoved the efficiency of transfection, cell uptake of siRNA, downregulated HSP70 and HSP90 expression in VCaP cells on the mRNA and protein levels, and upregulated major apoptotic markers (PARP-1, caspase-8, caspase-3 and cleaved caspase-3), thus, inducing extensive tumor-specific apoptosis. The Cell Counting Kit-8 assay showed decreased cellular viability in the HSP72/HSC70-siRNA silenced group. These results suggest that the combination of UTMD with dual targeting of HSP72 and HSC70 may improve the specific and efficient cell uptake of siRNA, inhibit HSP90 function and induce extensive tumor-speciﬁc apoptosis, indicating a novel, potential means for targeting therapeutic strategy to prostate cancer cells.
authors.affiliation: Department of Ultrasound, Shanghai First People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200080, P.R. China.
authors.forename: Hanghui
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Ultrasound, Shanghai First People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200080, P.R. China.
authors.forename: Yixin
authors.initials: Y
authors.lastname: Song
authors.affiliation: Hong Hui Hospital, Xi'an Jiaotong University College of Medicine, Shaanxi 710054, P.R. China.
authors.forename: Dingjun
authors.initials: D
authors.lastname: Hao
authors.affiliation: Department of Ultrasound, Shanghai First People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200080, P.R. China.
authors.forename: Min
authors.initials: M
authors.lastname: Bai
authors.affiliation: Department of Ultrasound, Shanghai First People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200080, P.R. China.
authors.forename: Lifang
authors.initials: L
authors.lastname: Jin
authors.affiliation: Department of Ultrasound, Shanghai First People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200080, P.R. China.
authors.forename: Jiying
authors.initials: J
authors.lastname: Gu
authors.affiliation: Department of Ultrasound, Shanghai First People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200080, P.R. China.
authors.forename: Yijin
authors.initials: Y
authors.lastname: Su
authors.affiliation: Department of Ultrasound, Shanghai First People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200080, P.R. China.
authors.forename: Long
authors.initials: L
authors.lastname: Liu
authors.affiliation: Department of Ultrasound, Shanghai First People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200080, P.R. China.
authors.forename: Chao
authors.initials: C
authors.lastname: Jia
authors.affiliation: Department of Ultrasound, Shanghai First People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200080, P.R. China.
authors.forename: Lianfang
authors.initials: L
authors.lastname: Du
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D045744:Cell Line, Tumor; D003131:Combined Modality Therapy; D015972:Gene Expression Regulation, Neoplastic; D050883:HSC70 Heat-Shock Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D050884:HSP72 Heat-Shock Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D018841:HSP90 Heat-Shock Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D006801:Humans; D008297:Male; D045423:Microbubbles; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D034622:RNA Interference; D014463:Ultrasonography
chemical_list: D050883:HSC70 Heat-Shock Proteins; D050884:HSP72 Heat-Shock Proteins; D018841:HSP90 Heat-Shock Proteins; C494371:HSPA8 protein, human