RÉSUMÉ
Objective:To explore the effects of estrogen receptor α (ERα) encoded by protein encoding gene ESR1 on the radiation resistance of breast cancer cells and their molecular mechanisms.Methods:The ESR1 overexpression plasmid was transfected into estrogen receptor (ER)-negative breast cancer cells. Then, the shRNA-ESR1 vector was introduced into ER-positive cell to establish models with different phenotype. The ATG5 mRNA level and protein expression levels of LC3B-I, LC3B-II, P62, FIP200, ATG5, ATG7, ATG12, Beclin1, ULK1 were detected using qPCR and Western blot techniques. Cell death was measured using flow cytometry. The radiation sensitivity was determined through the colony formation assay. The mortality of breast cancer cells under the autophagy gene knockdown and overexpression or treated with estrogen receptor inhibitor (TAM) combined with ionizing radiation were detected by trypan blue staining.Results:Under the condition of 8 Gy X-ray irradiation, the knockdown of ESR1 in ER-positive ZR75 breast cancer cells promoted cell death ( t = 3.49, 3.13, P < 0.05), while the overexpression of ESR1 in ER-negative MDA-MB-231 breast cancer cells inhibited cell death ( t = 4.16, 7.48, P < 0.05). Compared to the control group, the treatment with chloroquine increased the number of formed colonies of ESR1 knockdown ZR75 cells ( t = 8.49, P < 0.05), and inhibiting autophagy could reduce the death of ZR75 cells caused by ESR1 silencing. Under the treatment with ionizing radiation, the overexpression of ESR1 in MDA-MB-231 cells promoted protective autophagy, which, however, was reduced after ESR1 knockdown in ZR75 cells. Furthermore, it was observed that the knockdown of ATG5 in ZR75 cells was associated with reduced autophagy and an increase in cell death ( t = 4.19, 6.39, P < 0.05). In contrast, the overexpression of ATG5 in ZR75 cells reversed the increase in cell death caused by ESR1 knockdown ( t = 1.70, 4.65, P < 0.05). After the treatment of ER-positive ZR75 breast cancer cells with TAM, the expressions of ATG5 and ATG12 decreased, suggesting inhibited autophagy and an increase in cell death ( t = 18.70, P < 0.05). Furthermore, these processes were promoted by ionizing radiation ( t = 16.82, P < 0.05). Conclusions:The estrogen receptor encoded by ESR1 promotes protective autophagy of ER-positive breast cancer cells by increasing ATG5, further leading to radiation resistance in ER-positive breast cancer cells. Treatment with tamoxifen combined with ionizing radiation can increase the radiation sensitivity of ER-positive breast cancer cells.
RÉSUMÉ
Objective To explore the diagnostic value of color Doppler ultrasound for fetal intrauterine distress(FIUD)in high-risk puerperae in plateau areas.Methods A total of 130 puerperae in plateau areas and 130 puerperae in plain areas were enrolled.According to presence or absence of FIUD in different areas,they were divided into the plateau distress group(47 cases),the plateau normal group(83 cases),the plain distress group(31 cases)and the plain normal group(99 cases).All cases underwent blood flow detection of middle cerebral artery(MCA)and umbilical artery(UA)before delivery,and cerebral-placental ratio(CPR)was calculated.The incidence of FIUD was compared between high-risk puerperae in plateau area and in plain area.Gestational age,birth weight,cesarean section rate and blood spectrum parameters of MCA and UA were compared between the four groups.The predictive value of color Doppler ultrasound parameters for FIUD was analyzed by receiver operating characteristic(ROC)curves.Results The incidence rates of FIUD and severe FIUD were higher in patients of plateau areas than those in plain areas(36.15%,13.85%vs.23.85%,4.62%,P＜0.05).Compared with the plateau distress group,gestational age and birth weight were increased in the plateau normal group and the plain distress group(P＜0.05).Compared with the plateau distress group,PI,RI,S/D and CPR of MCA were increased,while PI,RI and S/D of UA were decreased in the plateau normal group and the plain distress group(P＜0.05).Results of ROC curve analysis showed that overall performance advantage of S/D of UA was the most obvious in the diagnosis of FIUD in high-risk puerperae in plateau areas.The diagnostic sensitivity of RI of MCA was the highest,and the diagnostic specificity of CPR was the highest(P＜0.05).Conclusion Color Doppler ultrasound has good diagnostic value for FIUD in high-risk puerperae in plateau areas,which can be applied as an effective clinical screening means for FIUD.
RÉSUMÉ
Objective:To evaluate the effect of long non-coding RNA PRMT5-AS1 on ferroptosis of hepatocellular carcinoma cell(HCC) after ionizing irradiation.Methods:The PRMT5-AS1 overexpression model was constructed in MHCC-97H cells and the PRMT5-AS1 knockdown model was constructed in HepG2 cells. X-ray irradiation(IR) was performed with an absorbed dose of 10 Gy and a dose rate of 3 Gy/min. Western blot and qRT-PCR were used to detect gene expression. The effect of PRMT5-AS1 expression on lipid peroxidation and ferroptosis of HCC after IR was detected by Trypan blue staining flow cytometry. The effect of PRMT5-AS1 expression on the death of HCC after IR was detected by CCK-8 assay. Dual luciferase assay to detect the binding of let-7c-5p to PRMT5-AS1 and SLC7A11.Results:Overexpression of PRMT5-AS1 in MHCC-97H cells could significantly reduce cell death induced by IR (Vector vs. PRMT5-AS1: 27.57% vs.18.30%, t=14.94, P<0.05). Knockdown of PRMT5-AS1 in HepG2 cells significantly increased cell death induced by IR (siNC vs. siPRMT5-AS1: 17.26% vs. 28.26%, t=13.63, P<0.05). Flow cytometry result show that overexpression of PRMT5-AS1 can significantly inhibit the increase of intracellular lipid ROS level induced by IR (Vector vs. PRMT5-AS1: 17.01% vs. 12.52%, t=12.80, P<0.05), and knockdown of PRMT5-AS1 significantly increases the lipid ROS level induced by IR (siNC vs. siPRMT5-AS1: 14.54% vs. 17.72%, t=5.93, P<0.05). The result of CCK-8 experiment showed that overexpression of PRMT5-AS1 could significantly inhibit Erastin induced cell activity reduction (Vector vs. PRMT5-AS1: 87.92% vs. 109.06%, t=2.87, P<0.05), and knockdown of PRMT5-AS1 could promote Erastin′s inhibitory effect on cell activity (siNC vs. siPRMT5-AS1: 82.56% vs. 60.58%, t=38.35, P<0.05). Western blot and fluorescent quantitative PCR result showed that the protein and mRNA levels of SLC7A11 were significantly increased after overexpression of PRMT5-AS1 ( t=26.24, P<0.05), and the protein and mRNA levels of SLC7A11 were significantly decreased after knockdown of PRMT5-AS1 ( t=5.60, P<0.05). The correlation between PRMT5-AS1 and let-7c-5p was confirmed by luciferase report gene experiment ( t=9.74, P<0.05). The result of luciferase reporter gene experiment showed that PRMT5-AS1 could form ceRNA network with let-7c-5p to regulate SLC7A11. Let-7c-5p was able to reverse the increase in SLC7A11 expression levels, decrease in Lipid-ROS levels and cell death induced by overexpression of PRMT5-AS1 ( t=3.01, 4.11, P<0.05). And knockdown of SLC7A11 reversed Lipid-ROS inhibition and reduced cell death caused by PRMT5-AS1( t=21.35, 7.15, P<0.05). Conclusions:LncRNA PRMT5-AS1 inhibits IR-induced ferroptosis in HCC through the PRMT5-AS1/let-7c-5p/SLC7A11 axis.
RÉSUMÉ
ObjectiveTo analyze the characteristics and trends of notifiable infectious diseases in Yangpu District of Shanghai， from 1950 to 2020， and to provide scientific basis for the formulation of control measures. MethodsDescriptive epidemiological method was used to collect and analyze the epidemiological data of notifiable infectious diseases. ResultsA total of 1 186 675 cases from 38 types of infectious diseases were reported. The annual morbidity of Class A and Class B infectious diseases fluctuated between 138.22/105 and 7 861.45/105， showing a decreasing trend. Among the 3 785 cases of death， the top five were measles， viral hepatitis， dysentery， tuberculosis and epidemic cerebrospinal meningitis. The high incidence diseases were intestinal infectious diseases， and the respiratory infectious diseases fluctuated in a wide range. Furthermore， blood-borne infectious diseases and sexual -transmitted diseases had continued to increase in recent years. As the result of normative vaccination， the incidence of associated infectious disease showed a downward trend. ConclusionThe incidence of infectious diseases in Yangpu District was on the drop from 1950 to 2020. Prevention and control work should focus on respiratory infectious diseases， blood-borne infectious diseases and sexual -transmitted diseases in the future. Furthermore， it is important to guarantee normative vaccination， especially， for prevention and control of infectious diseases.
RÉSUMÉ
With the development of modern computing technology and medical physics,radiotherapy has made great progress.The theoretical basis of radiobiology seems to lag behind the clinical application of radiotherapy,which hampers the further improvement of treatment efficacy and the optimization of treatment modality.In this paper,some emerging challenges of precision radiotherapy technology to the traditional theory of radiobiology,such as radiosensitivity,dose-response curve and survival curve,linear-quadratic model,4Rs theory,as well as the interaction between cancer and microenvironment,radiation-induced second primary cancers (RISPC),will be discussed.The interplay between precision radiotherapy and traditional radiobiology theories will be addressed with the aim to potentially solve some of the challenging problems.
RÉSUMÉ
Warfarin is widely used as an oral anticoagulant in clinic in China. It has narrow therapeutic index, large individual differences on dosage and the variability in warfarin dosage depends on many factors, including gene polymorphism, age, diet habits and so on. For clinicians, how to optimize the individual therapeutic regimen of warfarin is becoming a significant part of their work. In recent years, studies on genetic pharmacogenomics of warfarin are reported frequently. It is found that multiple gene polymorphisms can affect the efficacy of warfarin. We will introduce the gene polymorphism of some warfarin related genes and their effects on warfarin, and the advances of warfarin individual therapeutic regimen will also be discussed here.
RÉSUMÉ
Objective To discuss the clinical features and coronary artery lesions in middle-aged and young patients of coronary heart disease complicated with diabetes mellitus. Methods The clinical data of 386 middle-aged and young patients (aged from 28 to 59 years) of coronary heart disease were retrospectively analyzed. Among them, 176 cases were complicated with diabetes mellitus (diabetes group) and 210 cases didn′t have diabetes mellitus (non diabetes group). The general information, echocardiography and coronary angiography results between 2 groups were compared. Results The female ratio, incidences of hypertension and body mass index (BMI) in diabetes group were significantly higher than those in non diabetes group:28.4%(50/176) vs. 6.7%(14/210), 63.6%(112/176) vs. 43.8%(92/210) and (26.5 ± 2.5) kg/m2 vs. (23.8 ± 1.7) kg/m2, and there were statistical differences (P0.05). The total cholesterol (TC) and triglyceride (TG) in diabetes group were significantly higher than those in non diabetes group:(4.96 ± 1.32) mmol/L vs. (4.67 ± 1.12) mmol/L and (2.77 ± 2.01) mmol/L vs. (2.09 ± 1.60) mmol/L, the high-density lipoprotein cholesterol (HDL-C) was significantly lower than that in non diabetes group:(0.92 ± 0.30) mmol/L vs. (1.10 ± 0.32) mmol/L, and there were statistical differences (P0.05). There were no significant differences in the left atrial diameter, right ventricular diameter, left ventricular end diastolic diameter, ejection fraction, aortic root inside diameter and incidence of weakened ventricular wall motion between 2 groups (P>0.05). The incidence of 3 branch coronary artery lesions in diabetes group was significantly higher than that in non diabetes group:59.1%(104/176) vs. 37.6%(79/210), and there was statistical difference (P0.05). Conclusions In middle-aged and young patients of coronary heart disease complicated with diabetes mellitus, the female ratio is higher and hypertension, obesity and hyperlipidemia is more common. The lesions of coronary artery are more serious and diffuse. Three branch coronary artery lesions are the main ones, and the left main branch and the circumflex branch lesion is common.
RÉSUMÉ
Warfarin is widely used as an oral anticoagulant in clinic in China. It has narrow therapeutic index, large individual differences on dosage and the variability in warfarin dosage depends on many factors, including gene polymorphism, age, diet habits and so on. For clinicians, how to optimize the individual therapeutic regimen of warfarin is becoming a significant part of their work. In recent years, studies on genetic pharmacogenomics of warfarin are reported frequently. It is found that multiple gene polymorphisms can affect the efficacy of warfarin. We will introduce the gene polymorphism of some warfarin related genes and their effects on warfarin, and the advances of warfarin individual therapeutic regimen will also be discussed here.
RÉSUMÉ
Objective To evaluate the efficacy and safety between femoral artery compression hemostat and artificial compression after puncture of femoral artery. Methods The clinical data of 125 patients who had underwent puncture of femoral artery were retrospectively analyzed.The patients were divided into 2 group according to the hemostasis:artificial compression hemostasis(68 cases)and femoral artery compression hemostat group (57 cases). The performer operation time, performer operation difficulty score, performer fatigue level score, patient postoperative braking time, patient comfort score and complications of puncture were compared between 2 groups.Results The performer operation time, performer operation difficulty scores, performer fatigue level scores, patient postoperative braking time and patient comfort scores in femoral artery compression hemostat group were significantly better than those in artificial compression hemostasis group:(9.12 ± 3.57)min vs.(28.97 ± 2.85)min,(1.16 ± 0.75) scores vs. (1.59 ± 0.73) scores, (0.68 ± 0.60) scores vs. (2.72 ± 0.46) scores, (8.64 ± 6.02) h vs. (26.10 ± 11.42)h and(2.36 ± 0.57)scores vs.(3.76 ± 0.58)scores,there were statistical differences(P<0.01 or<0.05). There were no statistical difference in puncture sheath tube type, drug using and complications of puncture between two groups (P>0.05). Conclusions Compared with artificial compression after femoral artery puncture,femoral artery compression hemostat can reduce the operation time, shorten the patient braking time, and improve patient comfort, it has a better clinical application prospects.
RÉSUMÉ
Objective To elucidate the related risk factors for the cardiorenal syndrome(CRS),and to provide a reference for the prevention and treatment of CRS. Methods A retrospective study was conducted on 269 patients with chronic heart failure. The subjects were divided into two groups in accordance with estimated glomerular filtration rate(eGFR):patient group(CRS group),eGRF0.05)between the two groups in regard to white blood cell count,glutamic-pyruvic transaminase,glutamic oxalacetic transaminase,cholesterol,triglycerides,high density lipoprotein,low density lipoprotein,troponin I,serum free triiodothyronine,serum free thyroxine,or thyroid stimulating hormone. Multivariate logis-tic regression analysis showed that older age,low body weight,history of hypertension,history of diabetes,hypoalbuminemia,superb sensitivity C-re-active protein levels,high uric acid,high cystatin C hyperlipidemia,and low ejection fraction were independently associated with the occurrence of CRS. Conclusion Older age,low body weight,history of hypertension,history of diabetes,hypoalbuminemia,high-sensitivity C-reactive protein levels,high uric acid,high cystatin C hyperlipidemia,and low ejection fraction are the high risk factors for CRS in heart failure patients and are inde-pendently associated with the occurrence of CRS. Early identification and control of these risk factors are important for the prevention and treatment of CRS.
RÉSUMÉ
Objective To research the relationship between miR-21 and radiation sensitivity of cervical cancer HeLa cells,and to elucidate the possible action mechanism of miR-21 in apoptosis and autophagy of cells.Methods The HeLa cells were divided into mock groups (transfected with miR-21 NC,mimics,inhibitor NC or inhibitor)and 4 Gy irradiation groups (transfected with miR-2 1 NC, mimics,inhibitor NC or inhibitor with irradiation). The miR-2 1 expression was detected by real-time PCR;colony-forming assay was used to detect the changes of radiation sensitivity;the apoptosis and autophagy were analyzed by FACS assay;the target gene of miR-2 1 was predicted by bioinformatics methods;Dual-luciferase Reporter Assay was used to demonstrate the binding of miR-2 1 and targets;the expression of beclin1 protein was measured by Western blotting method. Results After 4 Gy radiation,compared with mock group,the expression of miR-21 was increased remarkably (P0.05).Compared with miR-21 NC+4 Gy group,the apoptotic rate of HeLa cells in miR-21 mimics+4 Gy group was increased (P<0.05).After transfection with miR-21 inhibitor,compared with miR-21 inhibitor NC group,the apoptotic rate of HeLa cells in duced by radiation was decreased (P<0.05 ). Compared with miR-21 NC group, the autophagy rate was increased after transfection with miR-21 mimics (P<0.05).After transfection with miR-21 mimics and radiation, the expression level of beclin1 protein was increased (P<0.05 ) compared with miR-21 NC+4 Gy group. Conclusion Beclin1 is the target gene of miR-21 in HeLa cells. Overexpression of miR-21 can increase the radiation-induced apoptosis and autophagy,but has on influence in radiation sensitivity of HeLa cells.
RÉSUMÉ
Objective To investigate the clinical efficacy,safety and the correlation factors of recurrence of radiofrequency catheter ablation in treatment of atrial fibrillation.Methods The clinical data of 127 patients with atrial fibrillation having underwent circumferential pulmonary vein ablation guided by 3-D mapping system were analyzed retrospectively.Then they were followed up for 12 months.The status of patients after ablation and the success rate of ablation was recorded,then the relationship between the factors and the recurrence after ablation of atrial fibrillation was analyzed.Results After a follow up of 12 months,94 patients maintained sinus rhythm,and atrial fibrillation recurred in 33 cases.The first clinical success rate was 74.02％(94/127).Thirty-three patients with recurred atrial fibrillation received ablation again and 11 patients got success.The total clinical success rate was 82.68％ (105/127).The success rate of paroxysmal atrial fibrillation was 88.46％ (92/104) and success rate of persistent atrial fibrillation was 56.52％ (13/23).Univariate analysis showed that the type,the course,the diameters of left atrial,the early recurrence,the body mass index were related to the recurrence of atrial fibrillation,and multivariable Logistic analysis revealed only the type and the diameters of left atrial were independent risk factors responsible for the recurrence of atrial fibrillation (P ＜ 0.05).Conclusion Radiofrequency catheter ablation in treatment of atrial fibrillation is effective and safe,and the type and the diameters of left atrial are independent risk factors responsible for the recurrence of atrial fibrillation.
RÉSUMÉ
Objective To investigate the effects of repeated computed tomography (CT) scan on hematological and immunological index in mice,and to explore the related mechanism.Methods A total of 60 BALB/c mice were randomly divided into six groups as control,once,twice,4,6 and 8 times of CT scans,and administered with whole-body scan by 64-slice spiral CT with the pelvis scan mode.Thermoluminescence dosimeter was used to detect the absorbed doses of CT scan,while DNA damage (γ-H2AX),apoptosis,autophagy,cell cycle and percentages of CD4/CD8 in peripheral lymphocytes and bone marrow cells were analyzed by flow cytometry.γ-H2AX was detected 1 h after the last CT scan,and the other indexes were detected 24 h after the last CT scan.Results γ-H2AX increased after more than twice CT scans in peripheral lymphocytes and after than 4 times of CT scan in bone marrow cells (P ＜ 0.05).Apoptosis increased in peripheral blood lymphocytes and decreased in bone marrow cells after more than 4 times of CT scan (P ＜ 0.05),suggesting that lymphocytes were more sensitive while different cell subpopulation in bone marrow showed different sensitivity and response phase.No obvious changes of autophagy level were observed in peripheral blood lymphocytes,while autophagy increased in bone marrow cells after single CT scan (F =81.10,P ＜ 0.05).8 times of CT scan significantly increased the percentages of cells at G0/G1 phase and G2/M phase(x2 =11.29,28.57,P ＜0.05).The percentage of CD4 + T,CD8 + T cells decreased after CT scan,but no effects on the ratio of CD4 +/CD8 +.Conclusions Repeated CT scans could induce injury effects on hematopoietic system and immune system,and then the apoptosis.Apoptosis,autophagy and cell cycle arrest might be initiated to maintain genome stability but there is no influence on immune balance.
RÉSUMÉ
Objective To study the effects of hypoxia-inducible factor-1α (HIF-1α) on radiationinduced autophagic cell death in breast cancer cells.Methods MCF-7 cells were divided into four groups:control (normoxia,21％ Oxygen),irradiation (8 Gy X-rays),hypoxia (Cobalt chloride,CoCl2)and irradiation with hypoxia (CoCl2).150 μmol/L CoCl2 was utilized to induce hypoxic conditions.Western blot was applied to detect the expression of HIF-1α and MAPLC3.MDC and Hoechst staining were used to detect autophagy and apoptosis.Radiosensitivity was detected by cloning formation.The short hairpin interfering RNA (shRNA) retroviral transduction particles targeting HIF-1α was transfected into MCF-7 cells to establish HIF-1 α knockdown cells,then the radiosensibility,autophagy and apoptosis were detected.Results Compared with control group and irradiation group,the protein level of HIF-1 increased obviously in the normaxia,irradiation,hypoxia and irradiation with hypoxia groups,and the values were 0,0,1.00,1.89,respectively.The expression levels of MAPLC3 were markedly up-regulated in irradiation,hypoxia and irradiation with hypoxia groups as compared with control,and the ratios of LC3Ⅱ/LC3Ⅰ were 1.15,1.73,2.38 and 3.60,respectively.The radiosensitivity of MCF-7 cells decreased in the following order:normoxia with 3MA ＞ normoxia ＞ hypoxia with 3MA ＞ hypoxia.HIF-1α knockdown cell (pSUPER-HIF-1α Ri) and vector control were constructed.After treatment with CoCl2,survival fraction of MCF-7-pSUPER was significantly higher than that of control (t =3.080,6.946,6.658,6.380,P ＜0.05),and radiosensitivity was down-regulated after irradiation,but there was no significant difference between normoxia and hypoxia in survival fraction of MCF-7-pSUPER-HIF-1α Ri.After treatment of irradiation or hypoxia,the autophagic fractions in MCF-7-pSUPER-HIF-1α Ri significantly decreased,reduced by 21.1％,25.5％,15.5％,respectively(t =4.635,4.738,6.354,P ＜0.05) as compared with MCF-7-pSUPER,but there was no change in apoptosis.Conclusions HIF-1α may increase radiationinduced autophagy and decrease radiosensitivity,but have no influence on apoptosis.
RÉSUMÉ
Objective To investigate the effect of different subtypes of fractionated doses on multidrug resistance in ovarian cancer cells.Methods The human ovarian cancer cell lines SKOV3 and its drug-resistant subtype SKVCR were divided into four groups i.e., sham-irradiated, single dose (10 Gy),fractionated dose (2 Gy × 5 ) and multi-fractionated dose (1 Gy × 2 × 5).Cell sensitivity to vincristine(VCR),etoposide ( VP-16),pirarubicin (THP) and cisplatin (DDP) was measured by MTT assay.Western blot was applied to detect the expression of P-gp after irradiation.Results The doubling time of SKVCR was about 1.8-fold of that of SKOV3 cells.P-gp was expressed in SKVCR but not in SKOV3.IC50 values of SKVCR were higher than those of SKOV3.To SKOV3 cells,single dose irradiation decreased cell sensitivity to THP and DDP and fractionated irradiation decreased cell sensitivity to VCR,THP and VP-16.Multi-fractionated irradiation decreased cell sensitivity to VP-16.In SKVCR cells,all these irradiation treatments increased cell sensitivity to VCR and VP-16 but not to DDP.In addition,single and fractionated irradiation decreased P-gp expression in SKVCR cells.Conclusions Single,fractionated and multi-fractionated radiation induced chemotherapy resistance in SKOV3 cells,while reversed drug resistance to VCR and VP-16 in SKVCR cells.
RÉSUMÉ
Objective To investigate the expression of DRAM in breast cancer cell line MCF-7 in radiation-induced autophagy. Methods GFP-LC3 transfection method was used to observe autophagy bubble.Real time-PCR was used to detect DRAM and MAPLC3 from transcriptional and translational level,respectively. The silencing vector from gene engineering was introduced by calcium phosphate transfection.Results Compared with the control group,GFP-LC3 increased significantly after 8 Gy irradiation by immunofluorescent assay,and the level of MAP-LC3 expression was higher than control group after 8 Gy irradiation by Western blot ( F =5.38,8.72,10.63,15.23,20.78 and 55.23,P ＜ 0.05 ).DRAM protein expression increased significantly at 2 h in the 8 Gy time-dose study,up to maximum at the 32 h( F =116.34,P ＜ 0.05 ).In DRAM model,the expression of LC3 and DRAM decreased significantly (F =20.36 and 40.35,P ＜ 0.05 ) and DRAM expression increased 8 Gy post-irradiation,but still lower than that in 8 Gy irradiation wild-type group.The LC3 expression also decreasaed 8 Gy post-irradiation(F =50.34,P ＜ 0.05 ).Conclusions DRAM plays an important role in irradiation-induced autophagy in breast cancer cell.DRAM might participate in the process and serve as a theoretical target for clinical treatment of breast cancer.
RÉSUMÉ
Objective To investigate the roles of dCK Ser-74 in radiation-induced cell death in breast cancer cells.Methods Different phenotypes of dCK plasmids were transfected into MCF-7 cells by liposome transfection,including dCK-Vector,dCK-WT (wild type),dCK-S74A (non-phosphorylation) and dCK-S74E (hyper-phosphorylation).All these cells were irradiated by 0,2,4,6,8 Gy X-rays,respectively.The transcriptional and translational level of dCK were detected with real time-PCR and Western blot,respectively.Radiosensitivity was analyzed using cell counting kit (CCK-8) and colony formation assays.Monodansylcadaverine staining (MDC) and flow cytometry were used to detect autophagy and apoptosis,respectively.Results Four phenotypes of dCK cell models were established successfully.After irradiation,the cell viabilities of MCF-7 and dCK-Vector decreased significantly as compared with mock group (t =14.469 and 9.357,P ＜ 0.05),the cell viabilities of dCK-WT,dCK-S74A and dCK-S74E showed no changes (P ＞ 0.05).The total mortalities of dCK-WT and dCK-S74E decreased significantly as compared with dCK-Vector (x2 =3.857-3.971,P ＜ 0.05),but no changes in dCK-S74A cells (P ＞0.05).The apoptosis rates in dCK-S74A,dCK-Vector and control group were up-regulated after irradiation (t =-4.531,-3.688 and-7.076,P ＜ 0.05),and the irradiation-induced apoptosis was reversed in dCK-WT and dCK-S74E (66％ and 68％ of the increase level in dCK-Vector group).The autophagy in dCK-WT and dCK-S74E increased by 22％ and 26％ (t =-9.051 and-8.411,P ＜0.01),but no changes were observed in dCK-S74A,dCK-Vector and control groups (P ＞ 0.05).Conclusions The dCK-WT and dCK-S74E could reverse the irradiation-induced apoptosis,increase the autophagy occurence,and decrease the total mortality,indicating that the phosphorylation of dCK at Ser-74 sites is related to the radiosensitivity of MCF-7 cells.
RÉSUMÉ
Objective To explore the roles of p53 in ionizing radiation induced MCF-7 cell cycle uncoupling. Methods The p53 knock-down models was established in MCF-7 with retrovirus packaged particles from 293T cells through calcium acid phosphate co-precipitation, then Western blot was used to detect the protein expression. Flow cytometry(FCM) was used to analyze the cell cycle uncoupling and polyploid after irradiation. Results Compared with p53+/+ group, the percentages of G0/G1 cells in p53 -/- group decreased, while those of S and G2+M increased (P < 0.01). In polyploidy analysis 2N cells decreased, whereas both 4N and 8N cells =increased (P<0.01). Compared with sham-irradiation, 4 Gy X-ray led to the decrease of G0/G1, S cells, and the increase of G2+M cells. The increase of 2N cells and decrease of 4N and 8N cells were observed in both p53+/+ and p53-/- cells. Compared with p53+/+ +IR group, the decrease of G0/G1 and S cells and the increase of C2 + M cells were significant (P < 0.01) in p53-/-+ IR groups. 2N cells decreased, 4N cells increased, but no changes in 8 N cells occurred. Conclusion Radiation might induce G2 arrest and cycle uncoupling, p53 plays a role in the regulation of G2 arrest, but no role in cycle uncoupling.
RÉSUMÉ
Objective To construct and identify the recombinant retroviral vectors expressing siRNA for MDR1 gene knock-down,sequentially to detect the reversing effect of RNAi on the multidrug resistant phenotype in MCF-7/ADR cells. Methods The target sequences of siRNAs for MDR1 knock-down were designed by IDTdna online. The DNA sequences containing a palindrome structure were synthesized and annealed to form double-stands which were inserted into linear pSUPER vectors later. The recombinant vectors were identified by agarose gel electrophoresis after cleaving of double enzymes and by sequencing,then were transfected into 293T packaging cells which produced retroviral particles in supernatant,the retrovirus soup was used to infect MCF-7/ADR cells. The expression level of MDR1 was detected from both mRNA level and protein level by RT-PCR and Western blotting,respectively. Results The recombinant pSUPER vectors expressing siRNA were confirmed by agarose gel electrophoresis after cleaving of double enzymes and by sequence analysis. The inserted oligonucleatide sequences were identical to the original sequences and in corresponding position. Compared with control group,the inhibitory effects of pSUPER.retro-MDR1 and pSUPER.retro-MDR2 were significant. Conclusion pSUPER recombinant retroviral vectors expressing siRNA for MDR1 knock-down is construted successfully,and it has inhibitory effect on the expression of MDR1 gene in MCF-7/ADR cells.
RÉSUMÉ
Objective To explore the prevention of asymptomatic coronary intimal lesion by controlling the risk factors of coronary heart disease(CHD).Methods The relationship between the intimal lesion(such as yellow plaque、plaque rupture and/or thrombus formation)and risk factors(such as hypertension、diabetes、high blood LDL-C、blood pressure and blood sugar in patients with high blood LDL-C)was investigated in the non-culprit vessels of 120 patients with old myocardial infarction and stable angina pectoris by applying coronary angioscopy.Results Totally 155 non-culprit vessels in 120 patients were explored and the following findings were observed:(1) There are 80 cases(66.67%)of intimal lesion,40 cases(33.33%)without intimal lesion.(2)In the group with intimal lesion,the simple yellow plaque was observed in 30 cases(25.00%)and complex plaque in 50 cases.(3) In 120 patients,hypertension was observed in 69 cases(57.50%),high blood LDL-C in 79 cases(65.83%)and type 2 diabetes in 40 cases(33.33%).(4)The complex plaques was less common in patients whose BP was less than 140/90 mm Hg than in patients more than 140/90 mm Hg(P0.05).Conclusion The plaque rupture can be well prevented which can reduce the incidence of ACS if the high blood pressure、high blood sugar、high LDL-C are controlled to an ideal level.