Figure 1.
EGF decreases DNA damage in irradiated HSCs via DNA-PKcs. (A) Immunofluorescence microscopy of IR-induced foci of γ-H2AX in nonirradiated (Non-IRR) and 300-cGy–irradiated BM KSL cells cultured in complete media (Media), with or without 10 ng/mL EGF for 1 hour (scale bar, 10 µm) (left panel). Numbers of foci per KSL cell in Non-IRR KSL cells (n = 20 replicates per group, 2-way ANOVA, horizontal lines represent means). (B) Representative images of a Comet assay of BM KSL cells that were irradiated (300 cGy) or not (Non-IRR) and cultured in media, with or without EGF, for 1 hour (scale bars, 100 µm) (left panel). Quantification of tail moments in each condition (n = 179-256 cells per group, 2-way ANOVA) (right panel). (C) Flow cytometric analysis of p-DNA-PKcs levels in Non-IRR KSL cells and irradiated (IRR; 100 cGy) KSL cells treated with Media alone or Media plus EGF for 1 hour (left panel). Percentage of p-DNA-PKcs+ KSL cells in each condition (n = 9-10 per group, 1-way ANOVA) (right panel). (D) Gene expression of Xrcc6 in Non-IRR KSL cells and at 1 hour following 300 cGy, treated or not with EGF (n = 4 per group, mean ± SEM, 2-way ANOVA). (E) Representative line graph of p-Artemis (Ser516) in KSL cells irradiated with 300 cGy and then treated or not with EGF for 1 hour (left panel). Percentage of p-Artemis+ KSL cells (n = 4 per group, mean ± SEM, Student t test) (right panel). (F) Fluorescence microscopy images of γ-H2AX foci in Non-IRR KSL cells and irradiated KSL cells in Media with or without EGF and with or without NU7441 (E+N; scale bar, 10 µm) (left panel). Numbers of γ-H2AX foci per KSL cell in each condition (n = 20 per group, 2-way ANOVA) (right panel). (G) Representative images of Comet assay of 300-cGy–irradiated KSL cells cultured with Media with or without EGF and with or without NU7441 (scale bars, 100 µm) (left panel). Tail moments from KSL cells from each condition (n = 102-114 cells per group, 1-way ANOVA) (right panel). (H) Numbers of CFCs from Non-IRR BM KSL cells and 300-cGy–irradiated KSL cells cultured in Media with or without EGF and with or without NU7441 for 72 hours (n = 6 per group, mean ± SEM, 2-way ANOVA). *P < .05, **P < .01, ***P < .001, ****P < .0001. IgG, immunoglobulin G.BFU-E, burst forming unit–erythroid; E+N, EGF + NU7441; GEMM, colony forming unit-granulocyte/erythroid/macrophage/megakaryocyte, GM,  colony forming unit-granulocyte/macrophage.

EGF decreases DNA damage in irradiated HSCs via DNA-PKcs. (A) Immunofluorescence microscopy of IR-induced foci of γ-H2AX in nonirradiated (Non-IRR) and 300-cGy–irradiated BM KSL cells cultured in complete media (Media), with or without 10 ng/mL EGF for 1 hour (scale bar, 10 µm) (left panel). Numbers of foci per KSL cell in Non-IRR KSL cells (n = 20 replicates per group, 2-way ANOVA, horizontal lines represent means). (B) Representative images of a Comet assay of BM KSL cells that were irradiated (300 cGy) or not (Non-IRR) and cultured in media, with or without EGF, for 1 hour (scale bars, 100 µm) (left panel). Quantification of tail moments in each condition (n = 179-256 cells per group, 2-way ANOVA) (right panel). (C) Flow cytometric analysis of p-DNA-PKcs levels in Non-IRR KSL cells and irradiated (IRR; 100 cGy) KSL cells treated with Media alone or Media plus EGF for 1 hour (left panel). Percentage of p-DNA-PKcs+ KSL cells in each condition (n = 9-10 per group, 1-way ANOVA) (right panel). (D) Gene expression of Xrcc6 in Non-IRR KSL cells and at 1 hour following 300 cGy, treated or not with EGF (n = 4 per group, mean ± SEM, 2-way ANOVA). (E) Representative line graph of p-Artemis (Ser516) in KSL cells irradiated with 300 cGy and then treated or not with EGF for 1 hour (left panel). Percentage of p-Artemis+ KSL cells (n = 4 per group, mean ± SEM, Student t test) (right panel). (F) Fluorescence microscopy images of γ-H2AX foci in Non-IRR KSL cells and irradiated KSL cells in Media with or without EGF and with or without NU7441 (E+N; scale bar, 10 µm) (left panel). Numbers of γ-H2AX foci per KSL cell in each condition (n = 20 per group, 2-way ANOVA) (right panel). (G) Representative images of Comet assay of 300-cGy–irradiated KSL cells cultured with Media with or without EGF and with or without NU7441 (scale bars, 100 µm) (left panel). Tail moments from KSL cells from each condition (n = 102-114 cells per group, 1-way ANOVA) (right panel). (H) Numbers of CFCs from Non-IRR BM KSL cells and 300-cGy–irradiated KSL cells cultured in Media with or without EGF and with or without NU7441 for 72 hours (n = 6 per group, mean ± SEM, 2-way ANOVA). *P < .05, **P < .01, ***P < .001, ****P < .0001. IgG, immunoglobulin G.BFU-E, burst forming unit–erythroid; E+N, EGF + NU7441; GEMM, colony forming unit-granulocyte/erythroid/macrophage/megakaryocyte, GM,  colony forming unit-granulocyte/macrophage.

Close Modal
This Feature Is Available To Subscribers Only

or Create an Account

Close Modal
Close Modal