title: Nitrosylhemoglobin in photodynamically stressed human tumors growing in nude mice.
abstract: The role of nitric oxide in human tumor biology and therapy has been the subject of extensive studies. However, there is only limited knowledge about the mechanisms of NO production and its metabolism, and about the role NO can play in modern therapeutic procedures, such as photodynamic therapy. Here, for the first time, we report the presence of nitrosylhemoglobin, a stable complex of NO, in human lung adenocarcinoma A549 tumors growing in situ in nude mice. Using electron paramagnetic resonance spectroscopy we show that the level of nitrosylhemoglobin increases in the course of photodynamic therapy and that the phenomenon is local. Even the destruction of strongly vascularized normal liver tissue did not induce the paramagnetic signal, despite bringing about tissue necrosis. We conclude that photodynamic stress substantiates NO production and blood extravasation in situ, both processes on-going even in non-treated tumors, although at a lower intensity.
authors: Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland. Electronic address: monika.jakubowska@uj.edu.pl.
authors: Monika
authors: M
authors: Jakubowska
authors: Dominika
authors: D
authors: Michalczyk-Wetula
authors: Janusz
authors: J
authors: Pyka
authors: Anna
authors: A
authors: Susz
authors: Krystyna
authors: K
authors: Urbanska
authors: Beata K
authors: BK
authors: Płonka
authors: Patryk
authors: P
authors: Kuleta
authors: Piotr
authors: P
authors: Łącki
authors: Martyna
authors: M
authors: Krzykawska-Serda
authors: Leszek
authors: L
authors: Fiedor
authors: Przemysław M
authors: PM
authors: Płonka
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D004578:Electron Spin Resonance Spectroscopy; D006454:Hemoglobins / Q000032:analysis / Q000378:metabolism*; D064593:Heterografts; D006801:Humans; D008099:Liver / Q000737:chemistry / Q000528:radiation effects; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008819:Mice, Nude; D009374:Neoplasms, Experimental / Q000737:chemistry / Q000378:metabolism* / Q000473:pathology* / Q000628:therapy; D009569:Nitric Oxide / Q000032:analysis / Q000378:metabolism; D010778:Photochemotherapy; D013154:Spleen / Q000737:chemistry / Q000528:radiation effects
chemical_list: D006454:Hemoglobins; C008657:nitrosyl hemoglobin; D009569:Nitric Oxide
keywords: 1,1-diphenyl-2-picrylhydrazyl; Adenocarcinoma; DPPH; EPR (ESR); Electron paramagnetic resonance; FCS; HSCs; HTM; HbNO; NOS; Nitric oxide; PD; PDT; PS; Photodynamic therapy; RNS (ROS); RTV; Zinc pheophorbide a; Zn-Pheide; electron paramagnetic (spin) resonance; fetal calf serum; human hemopoietic stem cells; humanized tumor mouse model; injection into peritoneum (vain); ip (iv); nitric oxide synthase; nitrosylhemoglobin; photodiagnosis; photodynamic therapy; photosensitizer; reactive nitrogen (oxygen) species; relative tumor volume; sc; subcutaneously; zinc pheophorbide a