Objective： By studying the influence of low-dose total body irradiation to proliferating cell nuclear antigens （PCNA）, epidermal growth factor receptor （EGFR）, erythropoietin （EPO） and vascular endothelial grow...Objective： By studying the influence of low-dose total body irradiation to proliferating cell nuclear antigens （PCNA）, epidermal growth factor receptor （EGFR）, erythropoietin （EPO） and vascular endothelial growth factor receptor （VEGFR） of tumor tissues in mice bearing S180 sarcoma, to further explore the mechanism of low doses radiation. Methods：S180 sarcoma cells were implanted subcutaneously into 58 male Kunming mice. Randomly these mice were divided into sham-irradiation （S） group and low-dose radiation （LDR） group. 12 days after implantation, the mice in LDR group were once delivered 75 mGy total-body ^60Co y-ray irradiation, while the mice in S group were left without irradiation. Then the mice in LDR group were executed at 6 h （LDR-6h group）, 12 h （LDR-12 h group）, 24 h （LDR-24 h group）, 48 h （LDR-48 h group） and 72 h （LDR-72h group） after irradiation. Tumor tissues were weighed and histological observed. Immunohistochemical staining was used to detect the expression of PCNA, VEGF, EPO and VEGFR of tumor tissues. Results： Though there was no significant difference between LDR group and S group in tumor weight, after irradiation the expression of PCNA and EPO of tumor tissues in LDR group decreased with time. LDR-24h, LDR-48h and LDR-72h groups were all statistically significantly different from S group. The expression of EGFR and VEGFR also decreased, and LDR-24h group was the lowest （P 〈 0.05）. Conclusion： Seventy-two h after low-dose total body irradiation, there was no significant change in tumor size of mice bearing S180 sarcoma. Low-dose total body radiation decreased the expression of PCNA inhibiting tumor growth; reduced the expression of EGFR in tumor tissue impacting the signal transduction of tumor cells. The study also indicated that low-dose total body irradiation, within a certain period of time, can decrease the expression of hypoxia factor EPO and VEGFR, which may improve the situation of tumor hypoxia and radiosensitivity of tumor itself.展开更多
AIM:To evaluate the feasibility of low contrast medium and radiation dose for hepatic computed tomography(CT) perfusion of rabbit VX2 tumor.METHODS:Eleven rabbits with hepatic VX2 tumor underwent perfusion CT scanning...AIM:To evaluate the feasibility of low contrast medium and radiation dose for hepatic computed tomography(CT) perfusion of rabbit VX2 tumor.METHODS:Eleven rabbits with hepatic VX2 tumor underwent perfusion CT scanning with a 24-h interval between a conventional tube potential(120 k Vp) protocol with 350 mg I/m L contrast medium and filtered back projection,and a low tube potential(80 k Vp) protocol with 270 mg I/m L contrast medium with iterative reconstruction.Correlation and agreement among perfusion parameters acquired by the conventional and low dose protocols were assessed for the viable tumor component as well as whole tumor.Image noise and tumor-to-liver contrast to noise ratio during arterial and portal venous phases were evaluated.RESULTS:A 38% reduction in contrast medium dose(360.1 ± 13.3 mg I/kg vs 583.5 ± 21.5 mg I/kg,P < 0.001) and a 73% decrease in radiation dose(1898.5 m Gy·cm vs 6951.8 m Gy·cm) were observed.Interestingly,there was a strong positive correlation in hepatic arterial perfusion(r = 0.907,P < 0.001;r = 0.879,P < 0.001),hepatic portal perfusion(r = 0.819,P = 0.002;r = 0.831,P = 0.002),and hepatic blood flow(r = 0.945,P < 0.001;r = 0.930,P < 0.001) as well as a moderate correlation in hepatic perfusion index(r = 0.736,P = 0.01;r = 0.636,P = 0.035) between the low dose protocol with iterative reconstruction and the conventional protocol for the viable tumor component and the whole tumor.These two imaging protocols provided a moderate but acceptable agreement for perfusion parameters and similar tumorto-liver CNR during arterial and portal venous phases(5.63 ± 2.38 vs 6.16 ± 2.60,P = 0.814;4.60 ± 1.27 vs 5.11 ± 1.74,P = 0.587).CONCLUSION:Compared with the conventional protocol,low contrast medium and radiation dose with iterative reconstruction has no significant influence on hepatic perfusion parameters for rabbits VX2 tumor.展开更多
Background Activating on mammalian and human body LDR is thought to induce adaptive response, enhance immune function and increase anti-tumor ability. This study was designed to assess the effect of low-dose radiati...Background Activating on mammalian and human body LDR is thought to induce adaptive response, enhance immune function and increase anti-tumor ability. This study was designed to assess the effect of low-dose radiation on tumor growth and on erythrocyte immune function and superoxide dismutase (SOD) activity in tumor-bearing mice. Methods Male Kunming mice were subcutaneously implanted with S 180 sarcoma cells in the right inguen to create an experimental in situ animal model. Six hours before implantation, the mice were given 75 mGy X-ray radiation, over the body. Tumor size was observed 5 days later while tumor volume was calculated every other day, allowing for the creation of a graph depicting tumor growth. Fifteen days after implantation, the mice were killed to measure tumor weight and observe the necrotic areas and the location of tumor-infiltrating lymphocytes (TILs). Erythrocyte immune function and SOD activity were also determined. Results Mice pre-exposed to low-dose radiation had a lower tumor formation rate than did those receiving no radiation (P<0.05). Tumor growth was significantly lower in the mice pre-exposed to low-dose radiation; after 15 days, the average tumor weight in the mice pre-exposed to low-dose radiation was also lower (P<0.05). Areas of tumor necrosis and infiltration of TILs were larger in the low-dose radiation group than in the non-radiation group. Erythrocyte immune function and SOD activity were higher in the low-dose radiation group than in the non-radiation group (P<0.05). Conclusion Low-dose radiation can markedly increase the anti-tumor ability of an organism and improve erythrocyte immune function and red blood cell SOD activity as well, suggesting that low-dose radiation might be useful in the clinical treatment of cancer.展开更多
基金Supported by a grant from the National Natural Scientific Foundation of China (No: 30030781)
文摘Objective： By studying the influence of low-dose total body irradiation to proliferating cell nuclear antigens （PCNA）, epidermal growth factor receptor （EGFR）, erythropoietin （EPO） and vascular endothelial growth factor receptor （VEGFR） of tumor tissues in mice bearing S180 sarcoma, to further explore the mechanism of low doses radiation. Methods：S180 sarcoma cells were implanted subcutaneously into 58 male Kunming mice. Randomly these mice were divided into sham-irradiation （S） group and low-dose radiation （LDR） group. 12 days after implantation, the mice in LDR group were once delivered 75 mGy total-body ^60Co y-ray irradiation, while the mice in S group were left without irradiation. Then the mice in LDR group were executed at 6 h （LDR-6h group）, 12 h （LDR-12 h group）, 24 h （LDR-24 h group）, 48 h （LDR-48 h group） and 72 h （LDR-72h group） after irradiation. Tumor tissues were weighed and histological observed. Immunohistochemical staining was used to detect the expression of PCNA, VEGF, EPO and VEGFR of tumor tissues. Results： Though there was no significant difference between LDR group and S group in tumor weight, after irradiation the expression of PCNA and EPO of tumor tissues in LDR group decreased with time. LDR-24h, LDR-48h and LDR-72h groups were all statistically significantly different from S group. The expression of EGFR and VEGFR also decreased, and LDR-24h group was the lowest （P 〈 0.05）. Conclusion： Seventy-two h after low-dose total body irradiation, there was no significant change in tumor size of mice bearing S180 sarcoma. Low-dose total body radiation decreased the expression of PCNA inhibiting tumor growth; reduced the expression of EGFR in tumor tissue impacting the signal transduction of tumor cells. The study also indicated that low-dose total body irradiation, within a certain period of time, can decrease the expression of hypoxia factor EPO and VEGFR, which may improve the situation of tumor hypoxia and radiosensitivity of tumor itself.
基金National Natural Science Foundation of China,No.NSFC 81171389Key Program of Basic Research from Shanghai Municipal Science and Technology Commission,No.12JC1406500the Program of Shanghai Municipal Health Outstanding Discipline Leader,No.XBR 2013110
文摘AIM:To evaluate the feasibility of low contrast medium and radiation dose for hepatic computed tomography(CT) perfusion of rabbit VX2 tumor.METHODS:Eleven rabbits with hepatic VX2 tumor underwent perfusion CT scanning with a 24-h interval between a conventional tube potential(120 k Vp) protocol with 350 mg I/m L contrast medium and filtered back projection,and a low tube potential(80 k Vp) protocol with 270 mg I/m L contrast medium with iterative reconstruction.Correlation and agreement among perfusion parameters acquired by the conventional and low dose protocols were assessed for the viable tumor component as well as whole tumor.Image noise and tumor-to-liver contrast to noise ratio during arterial and portal venous phases were evaluated.RESULTS:A 38% reduction in contrast medium dose(360.1 ± 13.3 mg I/kg vs 583.5 ± 21.5 mg I/kg,P < 0.001) and a 73% decrease in radiation dose(1898.5 m Gy·cm vs 6951.8 m Gy·cm) were observed.Interestingly,there was a strong positive correlation in hepatic arterial perfusion(r = 0.907,P < 0.001;r = 0.879,P < 0.001),hepatic portal perfusion(r = 0.819,P = 0.002;r = 0.831,P = 0.002),and hepatic blood flow(r = 0.945,P < 0.001;r = 0.930,P < 0.001) as well as a moderate correlation in hepatic perfusion index(r = 0.736,P = 0.01;r = 0.636,P = 0.035) between the low dose protocol with iterative reconstruction and the conventional protocol for the viable tumor component and the whole tumor.These two imaging protocols provided a moderate but acceptable agreement for perfusion parameters and similar tumorto-liver CNR during arterial and portal venous phases(5.63 ± 2.38 vs 6.16 ± 2.60,P = 0.814;4.60 ± 1.27 vs 5.11 ± 1.74,P = 0.587).CONCLUSION:Compared with the conventional protocol,low contrast medium and radiation dose with iterative reconstruction has no significant influence on hepatic perfusion parameters for rabbits VX2 tumor.
文摘Background Activating on mammalian and human body LDR is thought to induce adaptive response, enhance immune function and increase anti-tumor ability. This study was designed to assess the effect of low-dose radiation on tumor growth and on erythrocyte immune function and superoxide dismutase (SOD) activity in tumor-bearing mice. Methods Male Kunming mice were subcutaneously implanted with S 180 sarcoma cells in the right inguen to create an experimental in situ animal model. Six hours before implantation, the mice were given 75 mGy X-ray radiation, over the body. Tumor size was observed 5 days later while tumor volume was calculated every other day, allowing for the creation of a graph depicting tumor growth. Fifteen days after implantation, the mice were killed to measure tumor weight and observe the necrotic areas and the location of tumor-infiltrating lymphocytes (TILs). Erythrocyte immune function and SOD activity were also determined. Results Mice pre-exposed to low-dose radiation had a lower tumor formation rate than did those receiving no radiation (P<0.05). Tumor growth was significantly lower in the mice pre-exposed to low-dose radiation; after 15 days, the average tumor weight in the mice pre-exposed to low-dose radiation was also lower (P<0.05). Areas of tumor necrosis and infiltration of TILs were larger in the low-dose radiation group than in the non-radiation group. Erythrocyte immune function and SOD activity were higher in the low-dose radiation group than in the non-radiation group (P<0.05). Conclusion Low-dose radiation can markedly increase the anti-tumor ability of an organism and improve erythrocyte immune function and red blood cell SOD activity as well, suggesting that low-dose radiation might be useful in the clinical treatment of cancer.
