PURPOSE: To determine whether glioma cells irradiated with a microplanar X-ray beam exert bystander effects. METHODS AND MATERIALS: Microplanar beam irradiation of glioma cells in vitro was done using the SPring-8 synchrotron radiation facility. The amount of DNA double-strand breaks (dsbs) was measured by the fluorescence intensity of phosphorylated H2AX or the number of 53BP1 foci. The dose distribution in a cell population exposed to a single microplanar beam was determined by the amount of phosphorylated H2AX-positive cells. Bystander effects were determined by counting the number of 53BP1 foci in nonirradiated cells treated with conditioned medium from cultures of irradiated cells. RESULTS: More DNA dsbs were detected in cells adjacent to an area irradiated by the single beam than in cells in distant, nonirradiated areas as a result of bystander effects caused by scattered X-rays and DNA dsbs. In support of this, more 53BP1 foci were observed in nonirradiated, conditioned medium-treated cells than in control cells (i.e., cells not treated with irradiation or conditioned medium). These results suggest that DNA dsbs were induced in nonirradiated cells by soluble factors in the culture medium. In addition, we observed cellular migration into areas irradiated with peak doses, suggesting that irradiated cells send signals that cause nonirradiated cells to migrate toward damaged cells. CONCLUSIONS: Bystander effects are produced by factors secreted as a result of slit-type microplanar X-ray beam irradiation.
PURPOSE: To determine whether glioma cells irradiated with a microplanar X-ray beam exert bystander effects. METHODS AND MATERIALS: Microplanar beam irradiation of glioma cells in vitro was done using the SPring-8 synchrotron radiation facility. The amount of DNA double-strand breaks (dsbs) was measured by the fluorescence intensity of phosphorylated H2AX or the number of 53BP1 foci. The dose distribution in a cell population exposed to a single microplanar beam was determined by the amount of phosphorylated H2AX-positive cells. Bystander effects were determined by counting the number of 53BP1 foci in nonirradiated cells treated with conditioned medium from cultures of irradiated cells. RESULTS: More DNA dsbs were detected in cells adjacent to an area irradiated by the single beam than in cells in distant, nonirradiated areas as a result of bystander effects caused by scattered X-rays and DNA dsbs. In support of this, more 53BP1 foci were observed in nonirradiated, conditioned medium-treated cells than in control cells (i.e., cells not treated with irradiation or conditioned medium). These results suggest that DNA dsbs were induced in nonirradiated cells by soluble factors in the culture medium. In addition, we observed cellular migration into areas irradiated with peak doses, suggesting that irradiated cells send signals that cause nonirradiated cells to migrate toward damaged cells. CONCLUSIONS: Bystander effects are produced by factors secreted as a result of slit-type microplanar X-ray beam irradiation.
Authors: Hong Yuan; Lei Zhang; Jonathan E Frank; Christina R Inscoe; Laurel M Burk; Mike Hadsell; Yueh Z Lee; Jianping Lu; Sha Chang; Otto Zhou Journal: Radiat Res Date: 2015-08-25 Impact factor: 2.841
Authors: Tony J C Wang; Cheng-Chia Wu; Yunfei Chai; Roy K K Lam; Nobuyuki Hamada; Shizuko Kakinuma; Yukio Uchihori; Peter K N Yu; Tom K Hei Journal: PLoS One Date: 2015-08-28 Impact factor: 3.240
Authors: Cristian Fernandez-Palomo; Carmel Mothersill; Elke Bräuer-Krisch; Jean Laissue; Colin Seymour; Elisabeth Schültke Journal: PLoS One Date: 2015-03-23 Impact factor: 3.240
Authors: Karin Burger; Katarina Ilicic; Martin Dierolf; Benedikt Günther; Dietrich W M Walsh; Ernst Schmid; Elena Eggl; Klaus Achterhold; Bernhard Gleich; Stephanie E Combs; Michael Molls; Thomas E Schmid; Franz Pfeiffer; Jan J Wilkens Journal: PLoS One Date: 2017-10-19 Impact factor: 3.240