By a News Reporter-Staff News Editor at Women's Health Weekly -- Researchers detail new data in Oncology. According to news reporting originating from Irvine, California, by NewsRx correspondents, research stated, "Drug resistance acquired by cancer cells is a significant challenge in the clinic and requires impairing the responsible pathological pathway. Administering chemotherapeutics along with silencing resistance-basis activity using RNA interference (RNAi) is expected to restore the activity of the chemotherapeutic and generate synergistic cancer eradication."
Our news editors obtained a quote from the research from the University of California, "This study attempted to reverse tamoxifen (TAM)-resistance in breast cancer by silencing a mitochondrial enzyme, manganese superoxide dismutase (MnSOD), which dismutates TAM-induced reactive oxygen species (ROS) (i.e., superoxide) to less harmful hydrogen peroxide and hampers therapeutic effects. Breast cancer cells were co-treated with TAM and MnSOD siRNA-delivering nanoparticles (NPs) made of a siRNA/poly(amidoamine) (PAMAM) dendriplex core and an acid-degradable polyketal (PK) shell. The (siRNA/PAMAM)-PK NPs were designed for the PK shell to shield siRNA from nucleases, minimize detrimental aggregation in serum, and facilitate cytosolic release of siRNA from endosomal compartments. This method of forming the PK shell around the siRNA/PAMAM core via surface-initiated photo-polymerization enables ease of tuning NPs' size for readily controlled siRNA release kinetics. The resulting NPs were notably homogenous in size, resistant to aggregation in serum, and invulnerable to heparan sulfate-mediated disassembly, compared to siRNA/PAMAM dendriplexes. Gel electrophoresis and confocal microscopy confirmed efficient siRNA release from the (siRNA/PAMAM)-PK NPs upon stimuli-responsive hydrolysis of the PK shell. Sensitization of TAM-resistant MCF7-BK-TR breast cancer cells with (MnSOD siRNA/PAMAM)-PK NPs restored TAM-induced cellular apoptosis in vitro and significantly suppressed tumor growth in vivo, as confirmed by biochemical assays and histological observations."
According to the news editors, the research concluded: "This study implies that combined gene silencing and chemotherapy is a promising strategy to overcoming a significant challenge in cancer therapy."
For more information on this research see: Acid-degradable core-shell nanoparticles for reversed tamoxifen-resistance in breast cancer by silencing manganese superoxide dismutase (MnSOD). Biomaterials, 2013;34(38):10228-10237. Biomaterials can be contacted at: Elsevier Sci Ltd, The Boulevard, Langford Lane, Kidlington, Oxford OX5 1GB, Oxon, England. (Elsevier - www.elsevier.com; Biomaterials - www.elsevier.com/wps/product/cws_home/30392)
The news editors report that additional information may be obtained by contacting S.K. Cho, University of California, Dept. of Mol Biol & Biochem, Irvine, CA 92697, United States. Additional authors for this research include A. Pedram, E.R. Levin and Y.J. Kwon (see also Oncology).
Keywords for this news article include: Drugs, siRNA, Irvine, Anions, Genetics, Oncology, Stilbenes, Tamoxifen, California, Chemotherapy, Electrolytes, Nanoparticle, United States, Breast Cancer, Nanotechnology, Women's Health, Oxidoreductases, Benzene Derivatives, Superoxide Dismutase, Emerging Technologies, Enzymes and Coenzymes, Reactive Oxygen Species
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