title: Post-Transcriptional Regulation of the GASC1 Oncogene with Active Tumor-Targeted siRNA-Nanoparticles.
abstract: Basal-like breast cancer (BLBC) accounts for the most aggressive types of breast cancer, marked by high rates of relapse and poor prognoses and with no effective clinical therapy yet. Therefore, investigation of new targets and treatment strategies is more than necessary. Here, we identified a receptor that can be targeted in BLBC for efficient and specific siRNA mediated gene knockdown of therapeutically relevant genes such as the histone demethylase GASC1, which is involved in multiple signaling pathways leading to tumorigenesis. Breast cancer and healthy breast cell lines were compared regarding transferrin receptor (TfR) expression via flow cytometry and transferrin binding assays. Nanobioconjugates made of low molecular weight polyethylenimine (LMW-PEI) and transferrin (Tf) were synthesized to contain a bioreducible disulfide bond. siRNA complexation was characterized by condensation assays and dynamic light scattering. Cytotoxicity, transfection efficiency, and the targeting specificity of the conjugates were investigated in TfR positive and negative healthy breast and breast cancer cell lines by flow cytometry, confocal microscopy, RT-PCR, and Western blot. Breast cancer cell lines revealed a significantly higher TfR expression than healthy breast cells. The conjugates efficiently condensed siRNA into particles with 45 nm size at low polymer concentrations, showed no apparent toxicity on different breast cancer cell lines, and had significantly greater transfection and gene knockdown activity on mRNA and protein levels than PEI/siRNA leading to targeted and therapeutic growth inhibition post GASC1 knockdown. The synthesized nanobioconjugates improved the efficiency of gene transfer and targeting specificity in transferrin receptor positive cells but not in cells with basal receptor expression. Therefore, these materials in combination with our newly identified siRNA sequences are promising candidates for therapeutic targeting of hard-to-treat BLBC and are currently further investigated regarding in vivo targeting efficacy and biocompatibility.
authors.affiliation: Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University , Detroit, Michigan 48201, United States.|Department of Oncology, Karmanos Cancer Institute, Wayne State University , Detroit, Michigan 48201, United States.
authors.forename: Sara
authors.initials: S
authors.lastname: Movassaghian
authors.affiliation: Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University , Detroit, Michigan 48201, United States.
authors.forename: Yuran
authors.initials: Y
authors.lastname: Xie
authors.affiliation: Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University , Detroit, Michigan 48201, United States.|Department of Pharmaceutics and Biopharmaceutics, Kiel University , 24118 Kiel, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Hildebrandt
authors.affiliation: Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University , Detroit, Michigan 48201, United States.|Department of Oncology, Karmanos Cancer Institute, Wayne State University , Detroit, Michigan 48201, United States.
authors.forename: Rayna
authors.initials: R
authors.lastname: Rosati
authors.affiliation: Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University , Detroit, Michigan 48201, United States.
authors.forename: Ying
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University , Detroit, Michigan 48201, United States.
authors.forename: Na Hyung
authors.initials: NH
authors.lastname: Kim
authors.affiliation: Department of Chemical Engineering and Materials Science, College of Engineering, Wayne State University , Detroit, Michigan 48202, United States.
authors.forename: Denise S
authors.initials: DS
authors.lastname: Conti
authors.affiliation: Department of Pharmaceutics, College of Pharmacy, Virginia Commonwealth University , Richmond, Virginia 23298, United States.|Department of Chemical and Life Science Engineering, Virginia Commonwealth University , Richmond, Virginia 23284, United States.
authors.forename: Sandro R P
authors.initials: SR
authors.lastname: da Rocha
authors.affiliation: Department of Oncology, Karmanos Cancer Institute, Wayne State University , Detroit, Michigan 48201, United States.
authors.forename: Zeng-Quan
authors.initials: ZQ
authors.lastname: Yang
authors.affiliation: Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University , Detroit, Michigan 48201, United States.|Department of Oncology, Karmanos Cancer Institute, Wayne State University , Detroit, Michigan 48201, United States.|Department of Pharmacy, Pharmaceutical Technology and Biopharmaceutics, Ludwig-Maximilians-Universität München , 80539 Munich, Germany.
authors.forename: Olivia M
authors.initials: OM
authors.lastname: Merkel
mesh_terms: D015153:Blotting, Western; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000235:genetics / Q000502:physiology; D005260:Female; D005434:Flow Cytometry; D005786:Gene Expression Regulation / Q000235:genetics*; D006801:Humans; D056484:Jumonji Domain-Containing Histone Demethylases / Q000235:genetics / Q000378:metabolism*; D018625:Microscopy, Atomic Force; D018613:Microscopy, Confocal; D053758:Nanoparticles / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry; D034741:RNA, Small Interfering / Q000235:genetics*; D011990:Receptors, Transferrin / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014168:Transferrin / Q000378:metabolism
chemical_list: C413655:KDM4C protein, human; D011108:Polymers; D034741:RNA, Small Interfering; D011990:Receptors, Transferrin; D014168:Transferrin; D056484:Jumonji Domain-Containing Histone Demethylases
keywords: GASC1; artificial virus; breast cancer; nanoparticle; oncogene; polyethylenimine (PEI); siRNA; targeted therapy; targeting; transferrin; transferrin receptor