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Objective To construct the pshuttle-Egr-1-hSmac plasmid and transfect human breast cancer MDA-MB-435 cells,and to observe its radiotherapy enhancing effect on tumor cells.Methods The empty vector pshuttle and pshuttle-Egr-1-hSmac plasmid were transfected into MDA-MB-435 cells by liposomal.At different time(4,8,12,24 and 48 h)after irradiation with 2.0 Gy X-ray and 24 h after irradiation with 0.5 -5.0 Gy,the total RNA and protein were collected and extracted from these cells to analyze the Smac mRNA and protein expression levels with RT-PCR and Western blotting methods. The cells were divided into control, pshuttle, pshuttle-Egr-1-hSmac,2.0 Gy irradiation group, pshuttle + 2.0 Gy irradiation and pshuttle-Egr-1-hSmac+2.0 Gy irradiation groups.MTT method was used to evaluate cell proliferation,and the cell survival ability was measured with clone formation assay;Annexin Ⅴ/PI double staining and PI single staining were used to examine the apoptosis and cell cycle of MDA-MB-435 cells. Results There was no Smac mRNA expression in MDA-MB-435 cells in control and pshuttle groups,but the Smac mRNA expression levels in MDA-MB-435 cells in pshuttle-Egr-1-hSmac plasmid group were gradually increased with the time prolongation, and reached the maximum at 24 and 48 h;the Smac mRNA expression levels in MDA-MB-435 cells were increased gradually 24 h after irradiation of 0.5 - 5.0 Gy X-ray with the increasing of irradiation doses, and reached the maximum after 2.0 and 5.0 Gy irradiation. The Smac protein expression levels in pshuttle-Egr-1-hSmac plasmid group were increased gradually with the time prolongation,and reached the maximum at 24 h.The Smac protein expression lervels were increased 24 h afer irradiation of 0,0.5,1.0,2.0 and 5.0 Gy X-ray,especially in 5.0 Gy group. The MTT results showed that the A490 values in 2.0 Gy,pshuttle+2.0 Gy and pshuttle-Egr-1-hSmac groups 24, 48,and 72 h after irradiation were lower than those in control group(P<0.01);the A490 values of MDA-MB-435 cells in pshuttle-Egr-1-hSmac group after 1.0-5.0 Gy X-ray irradiation were lower than those in 0 Gy group (P<0.05 or P<0.01);the survival fraction(SF)in pshuttle-Egr-1-hSmac group was lower than those in control group (P<0.01).The percentages of the cells at G0/G1 and S phase in pshuttle-Egr-1-hSmac group were lower than those in 2.0 Gy group(P<0.01),the percentage of the cells at G2/M phase was higher than that in 2.0 Gy group (P<0.01);the apoptotic rate of the cells in pshuttle-Egr-1-hSmac group was higher than that in 2.0 Gy group (P<0.01).Conclusion X-ray irradiation can significantly increase the Smac mRNA and protein expression levels in MDA-MB-435 cells transfected with pshuttle-Egr-1-hSmac plasmid,inhibit the cell survival rate,and induce G2/M arrest and apoptotic increasing;Smac gene combined with radiotherapy could significantly increase the radiosensitivity of breast cancer cells.
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Objective To explore the effects of 75 mGy irradiation on the apoptosis of spermatogenic cells and antioxidant capacity of serum and testis and hormone levels in male rats with diabetes mellitus(DM).Methods Rats were injected intraperitoneally with streptozotocin(STZ)to develop diabetes.The diabetic rats were irradiated with 75 mGy X-rays every other day for 4 weeks.Their survival rate and body weight were recorded 12 weeks after development of diabetes.The apeptosis percentage of germ cells was measured with flow cytometry and TUNEL method.The changes of anti-oxidation and gonadal hormone levels in serum and testis were measured with kits.Results After the rats suffered from diabetes for 12 weeks,the survival rate in DM group was 25%(6/24),100% in normal control group(16116).The survival rate in 75 mGy + DM group(9/16,56.25%)was obviously higher than that in the DM group(X2= 4.00,P < 0.05).Meanwhile,the percentage of apaptotic spermatogenic cells in the diabetic rats was significantly larger than those in the normal control and irradiation groups(F = 5.496,P < 0.05).MDA and NO levels in serum and testis of diabetic rats were higher in varying degrees than that in the normal control,while the serum and testis MDA content in the 75 mGy + DM group were lower than those in the DM group especially in the testis(F = 10.644,P < 0.01).75 mGy X-ray irradiation decreased NO content in the diabetic rats serum significantly(F = 14.379,P < 0.05)and increased NOS activity and TS,FSH level(F = 9.676,43.194 and 5.282,respectively,P < 0.05 and P < 0.01).Conclusions LDR could decrease the MDA level and NO content,and increase the antioxidant enzyme activity and TS and FSH levels in testis and serum of diabetic rats.
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Objective To evaluate the radioprotective effects of Quercetin (QN) on 6 Gy X-ray irradiation-induced immune dysfunction and toxicity in hepatic tissue in rats. Methods 40 adult rats were randomly divided into 4 groups. Group Ⅰ was injected intraperitoneally with saline solution for 7 consecutive day sand served as control group. Group Ⅱ was daily injected with QN (40 mg/kg) for 7 consecutive days. Group Ⅲ was irradiated with a single dose of 6 Gy X-ray. Group Ⅳ received a daily injection of QN (40 mg/kg) for 7 consecutive days, and 1 h after the last injection rats were irradiated with a single dose (6 Gy) X-ray irradiation.The animals were sacrificed after 24 h. Lymphocyte transforming rate was measured with MTT method, and CD+4 T, CD+4 T and CD+8/CD+8 T were measured with flow cytometry method. Oxidative conditions in liver were measured with malondialdehyde (MDA), reduced glutathione hormone (GSH), supernxide dismutase (SOD) andglutathione peroxidase (GSH-Px) activities kits. HE staining was used to observe the general condition of rat's liver. Results Lymphocyte transforming rate, CD+4 T, CD+8 T and CD+8/CD+8 T in rats of Group Ⅳ were all higher than those in rats of Group Ⅲ ( F = 8.455,22.644, 18.911, P < 0.01 ). MDA content in the Group Ⅳ rat's liver was lower than that in the Group Ⅲ ( F = 10.059, P < 0.01 ) and antioxidant enzymes SOD, GSH-Px activities were higher than those in Group Ⅲ (F = 23.688,186.046,19.788, P < 0.01 ). The capillary of the hepatic lobules dilated and congested obviously in portal area, involving infiltration of polymorphonuclear leukocytes in the Group Ⅲ, while QN improved this change apparendy. Conclusions Pretreatment with Quercetin improved the irradiated rat's immune functions and protected the irradiated rats from oxidative stress to some extent.
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Objective To determine whether the use of 18F-FDG PET/CT alters staging and management of nasopharyngeal carcinoma (NPC) when compared with MRI staging practice;and to explore the relation of standard uptake value (SUV) of 18F-FDG PET/CT and the pathological classification and T staging of NPC. Methods The study was performed retrospectively on a group of 41 patients with a new diagnosis of NPC. All the patients underwent whole body PET/CT scanning and head & neck MRI scanning within 3 weeks of each other. The AJCC protocol was introduced to stage NPC and the results of the PET/CT were compared with MRI based on pathologic diagnosis. Results ①Primary tumor:the accuracy of T staging of PET/CT was significantly higher than MRI (85.37% vs 60.98%,U=2.49,P