title: Magnetic thermoablation stimuli alter BCL2 and FGF-R1 but not HSP70 expression profiles in BT474 breast tumors.
abstract: Magnetically induced heating of magnetic nanoparticles (MNP) in an alternating magnetic field (AMF) is a promising minimal invasive tool for localized tumor treatment that eradicates tumor cells by applying thermal stress. While temperatures between 42°C and 45°C induce apoptosis and sensitize the cells for chemo- and radiation therapies when applied for at least 30 minutes, temperatures above 50°C, so-called thermoablative temperatures, rapidly induce irreversible cell damage resulting in necrosis. Since only little is known concerning the protein expression of anti-apoptotic B-cell lymphoma 2 (BCL2), fibroblast growth factor receptor 1 (FGF-R1), and heat shock protein (HSP70) after short-time magnetic thermoablative tumor treatment, these relevant tumor proteins were investigated by immunohistochemistry (IHC) in a human BT474 breast cancer mouse xenograft model. In the investigated sample groups, the application of thermoablative temperatures (<2 minutes) led to a downregulation of BCL2 and FGF-R1 on the protein level while the level of HSP70 remained unchanged. Coincidently, the tumor tissue was damaged by heat, resulting in large apoptotic and necrotic areas in regions with high MNP concentration. Taken together, thermoablative heating induced via magnetic methods can reduce the expression of tumor-related proteins and locally inactivate tumor tissue, leading to a prospectively reduced tumorigenicity of cancerous tissues. The presented data allow a deeper insight into the molecular mechanisms in relation to magnetic thermoablative tumor treatments with the aim of further improvements.
authors: Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Jena, Germany.
authors: Marcus
authors: M
authors: Stapf
authors: Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Jena, Germany.
authors: Nadine
authors: N
authors: Pömpner
authors: Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Jena, Germany.
authors: Melanie
authors: M
authors: Kettering
authors: Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Jena, Germany.
authors: Ingrid
authors: I
authors: Hilger
mesh_terms: D000818:Animals; D001943:Breast Neoplasms / Q000628:therapy*; D045744:Cell Line, Tumor; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism*; D006801:Humans; D006979:Hyperthermia, Induced / Q000379:methods*; D055909:Magnetic Field Therapy / Q000379:methods*; D051379:Mice; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D051496:Receptor, Fibroblast Growth Factor, Type 1 / Q000378:metabolism*
chemical_list: D018840:HSP70 Heat-Shock Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; C496349:Fgfr1 protein, mouse; D051496:Receptor, Fibroblast Growth Factor, Type 1
keywords: breast cancer tumor; in vivo; magnetic nanoparticles (MNP); mouse model; thermoablation