辐射对食管癌Eca-109细胞COX-2表达的影响及其放射增敏意义

目的：探讨不同辐射剂量对食管癌Eca-109细胞COX-2表达的影响及其与放射敏感性的关系,为合理应用COX-2抑制剂提供实验依据。方法：X线照射食管癌Eca-109细胞,2Gy/f,以照射累积剂量（0Gy、20Gy、40Gy）将其分为Eca 109、Eca 109-20、Eca-109-40组;COX-2抑制剂尼美舒利培育Eca-109-40组细胞为Eca-109-40R;RT-PCR及Western-blot检测细胞COX-2的表达;克隆形成实验检测细胞放射敏感性;流式细胞仪检测细胞周期分布。结果：Eca-109-40细胞COX-2表达增高（P〈0.05）,放射敏感性降低（P〈0.05）,细胞周期S期比例增多（P〈0.05）,Eca 109与Eca 109-20之间差异无统计学意义（P〉0.05）,Eca-109-40R较Eca-109-40 COX-2表达下降（P〈0.05）,放射敏感性增高（P〈0.05）,细胞周期S期比例减少（P〈0.05）。结论：辐射累积剂量在40Gy时Eca-109细胞COX-2的表达较高,癌细胞放射敏感性降低;照射40Gy时加用尼美舒利可提高细胞放射敏感性。     

EGCG联合放疗治疗鼻咽癌裸鼠移植瘤模型

目的 研究表没食子儿茶素没食子酸酯(epigallocatechin-3-gallate,EGCG)对鼻咽癌裸鼠移植瘤放疗的增敏效应及survivin和VEGF的表达及意义.方法 体外培养低分化鼻咽癌CNE-2细胞,接种于20只雄性裸鼠皮下,待肿瘤结节约4～6 mm时,随机分为生理盐水组、EGCG组(30 mg/kg)...     

汉防己甲素对体外培养食管癌细胞放射增敏作用的初步研究

目的 探讨汉防己甲素对人食管癌TE1细胞放射增敏作用及其机制.方法 利用MTT法检测食管癌TE1细胞增殖活性影响,细胞克隆形成法测定汉防己甲素联合X射线对TE1细胞放射敏感性影响,Western blotting分析汉防己甲素联合X射线对TE1细胞周期蛋白表达的影响.结果 汉防己甲素对TE1细胞增殖抑制作用具有时间、浓度依赖性,1.00、5.00、10.00μg/ml浓度作用24 h时对TE1细胞增殖有抑制作用(F=3.09、10.43、24.00,P值均＜0.05),0.10、1.00、5.00、10.00μg/ml浓度作用48 h时对TE1细胞增殖有更显著地抑制作用(F=4.12、12.77、44.28、48.53,P值均＜0.01).随汉防己甲素浓度增加,TE1细胞的D0、Dq、SF2值均逐渐减小,0.5 μg/ml汉防己甲素的放射增敏比最大为1.60.汉方已甲素增加TE1细胞周期蛋白cyclin B1的表达,解除G2+M期阻滞.结论 汉防己甲素对TE1细胞有放射增敏作用,其机制可能是通过增加周期蛋白cyclin B1表达解除细胞G2+M期阻滞.     

沉默LncRNA OIP5-AS1通过上调miR-34c-5p表达增加A549R细胞放射敏感性

目的 探讨LncRNA OIP5-AS1对非小细胞肺癌放射抗拒细胞A549R的放射敏感性影响及作用机制。方法 X射线6Gy照射5次A549细胞建立放射抗拒细胞A549R。qRT-PCR检测A549、A549R细胞OIP5-AS1和miR-34c-5p表达水平。转染OIP5-AS1抑制剂或miR-34c-5p模拟物至A549R细胞,OIP5-AS1过表达质粒至A549细胞。流式细胞仪检测细胞凋亡,克隆形成实验检测细胞放射敏感性,蛋白印记检测p-Chk2和p-ATM蛋白表达水平。双荧光素酶实验验证OIP5-AS1与miR-34c-5p之间关系。结果 与A549细胞比,A549R细胞中OIP5-AS1表达上调(1.97±0.11︰1.01±0.05,P<0.05),miR-34c-5p表达下调(0.43±0.02︰1.02±0.06,P<0.05)。沉默OIP5-AS1+6Gy组A549R细胞中p-Chk2和p-ATM蛋白水平低于沉默对照+6Gy组(0.43±0.03︰1.39±0.15和0.51±0.05︰1.21±0.11,P<0.05),但凋亡率增加[(13.29±1.25)%︰(28.47±2.31)%,P<0.05]。过表达OIP5-AS1+6Gy组A549细胞中p-Chk2和p-ATM蛋白水平高于过表达对照+6Gy组(1.23±0.13︰0.75±0.06和1.08±0.11︰0.59±0.04,P<0.05)。抑制miR-34c-5p表达逆转了沉默OIP5-AS1对A549R细胞存活分数影响,增敏比为1.42。OIP5-AS1负调控miR-34c-5p表达。结论 沉默OIP5-AS1通过上调miR-34c-5p表达增强A549R细胞放射敏感性,为放疗提供潜在的靶点。     

Relationship between traditional Chinese medicine syndrome differentiation and imaging characterization to the radiosensitivity of nasopharyngeal carcinoma

Background and Objective: Traditional Chinese medicine (TCM) is a well established and time-honored practice in China, employing syndrome differentiation as a basis for the treatment of disease. According to different TCM syndrome typing findings, combining modern medical methods with TCM approaches can improve the quality of life and comprehensive effect on patients with nasopharyngeal carcinoma (NPC). This study investigated the relationship between TCM syndrome typing and imaging characterization to radi...     

The potential role of G2- but not of G0-radiosensitivity for predisposition of prostate cancer

Purpose

Comparing the chromosomal radiosensitivity of prostate cancer patients with that of healthy donors.

Materials and methods

The study was performed on 81 prostate cancer patients characterised by a clinical stage of predominantly pT2c or pT3a and a median age of 67 years. As healthy donors 60 male monozygotic twin pairs were recruited with a median age of 28 years. Chromosomal radiosensitivity was measured using both G0- and G2-assay.

Results

No difference between healthy donors and prostate cancer patients was detected concerning G0-radiosensitivity, since medians were similar (Hodges-Lehmann estimate: −0.05, 95% CI: −0.18-0.08, p = 0.4167). However, a pronounced difference was determined for G2-radiosensitivity with prostate cancer patients showing a significantly higher sensitivity compared to healthy donors (Hodges-Lehmann estimate: −0.41, 95% CI: −0.53 to −0.30, p = 1.75⁻⁹). Using the 90% quantile of G2-radiosensitivity in healthy donors as a threshold for discrimination the fraction of prostate cancer patients with elevated radiosensitivity increased to 49%.

Conclusion

G2-, but not G0-radiosensitivity is a promising marker for predisposition of prostate cancer.     

AEG-1表达下调对脑胶质瘤U373细胞的放射增敏效应

目的:探讨AEG-1基因表达下调对人脑胶质瘤细胞U373放射敏感性的影响。方法:以人MTDH/AEG-1（NM-178812）为靶标设计shRNA序列,慢病毒介导将AEG-1 shRNA转染至胶质瘤U373细胞中。荧光定量PCR及Western blot测定转染前后AEG-1 mRNA及蛋白的表达;克隆形成实验评估AEG-1基因下调后U373细胞放射敏感性;流式细胞术检测AEG-1下调后U373细胞凋亡及细胞周期分布。结果:通过慢病毒介导的shRNA转染,构建了AEG-1表达稳定下调的U373-shAEG-1细胞系,有效抑制了胶质瘤U373细胞中AEG-1的表达(抑制率84%,P<0.05),增加了凋亡细胞的比例（13.07%±0.28%,P<0.05）,并提高细胞周期中S期细胞比例（58.18％,P<0.01）,且AEG-1基因表达下调后U373细胞的D0值 （1.60Gy） 和Dq值 （1.06Gy）均明显低于空白对照组及阴性对照组细胞（P<0.05）。结论:下调AEG-1可以增强人脑胶质瘤U373细胞的放射敏感性,其机制与诱导细胞凋亡及干预细胞周期分布有关。     

AKT抑制剂对鼻咽癌细胞株CNE1的放疗增敏作用

【目的】 探讨Akt抑制剂124005对人鼻咽癌细胞CNE1放射增敏效应及其潜在机制。【方法】 CCK8法检测不同浓度124005对人鼻咽癌CNE1细胞的抑制作用,计算IC50值,选择低于IC50的药物浓度作为增敏浓度,集落形成实验检测放射线加或不加124005以及124005+放射线组联合或不联合自噬抑制剂3-MA对CNE1细胞生存曲线的影响,间接免疫荧光法检测γ-H2AX观察DNA损伤修复和GFP-LC3转染CNE1中自噬标志物LC3的聚集,流式细胞术检测细胞周期分布和凋亡、免疫印迹法(Western blot)检测Caspase-3、PARP、Beclin 1和LC3-Ⅱ的表达,并检测AKT及下游信号通路的表达,探索Akt抑制剂124005放射增敏效应及其潜在机制。【结果】 124005对CNE1 IC50值为30.5 μmol/L。集落形成实验显示,DEF值放疗+8 μmol/L 124005持续用药组为1.92,放疗+12.5 μmol/L 124005用药72 h组为1.12,共聚焦显微镜观察显示124005联合放疗显著增加了CNE1细胞照射后细胞核内γ-H2AX焦点的聚集和转染GFP-LC3质粒的CNE1细胞内LC3的点状聚集、流式检测124005可以明显提高放射线诱导的CNE1细胞凋亡,凋亡率最高达52.9%。Western blot显示124005可以显著抑制放射后p-AKT及下游p-GSK-3?茁和p-PRAS40的表达,增加放射引起的cleaved caspase-3和cleaved PARP以及Beclin 1和LC3-Ⅱ的表达,应用3-MA可降低124005处理后LC3-Ⅱ的表达水平?放射+124005再联用3 mmol/L 3-MA组的DEF值为1.69,明显低于单纯放射+124005组(DEF=1.97)。 【结论】 124005通过对AKT以及下游通路的抑制,抑制DNA损伤修复,同时增加凋亡和自噬来起到对CNE1细胞株放射增敏的效应。     

IGF －1R 抑制剂 OSI －906对鼻咽癌细胞 SUNE －1放射增敏作用的研究

目的：探讨酪氨酸激酶抑制剂（TKI）OSI －906对鼻咽癌 SUNE －1细胞放疗增敏的作用机制。方法：MTT 检测 OSI －906对 SUNE －1细胞增殖的影响;Western blot 检测 X 线照射（IR）、OSI －906对 IGF －1R／AKT 和 IGF －1R／ERK 信号通路的影响;流式细胞仪检测 OSI －906对细胞周期的影响;细胞克隆形成实验分析 OSI －906对 X 线照射敏感性的作用;激光共聚焦观察 OSI －906对 X 线照射 SUNE －1细胞 DNA 断裂的影响。结果：OSI －906明显抑制 SUNE －1细胞增殖;IR 可以激活 IGF －1R／AKT 和 IGF －1R／ERK 信号通路,而OSI －906可以抑制 IGF －1R／AKT 和 PI3K／ERK 信号通路激活;细胞周期分析显示,OSI －906可以增加细胞G2／M期比例;克隆形成实验提示 OSI －906提高 IR 对细胞的放射敏感性;焦点成型实验提示 OSI －906增加X 线照射细胞的γ－H2AX 焦点数。结论：OSI －906增加鼻咽癌细胞放疗敏感性,其机制可能与抑制 PI3K／AKT 和 Ras／MAPK 细胞增殖信号通路激活,改变细胞周期,诱导基因组不稳定性有关。     

Andrographolide radiosensitizes human esophageal cancer cell line ECA109 to radiation in vitro

To explore the radiosensitivity of andrographolide on esophageal cancer cell line ECA109. The inhibition effects of andrographolide were measured using 3‐(4,5‐dimethyl‐2‐thiazolyl)‐2,5‐diphenyl‐2H‐tetrazolium (MTT) assay. Clonogenic survival assay was used to evaluate the effects of andrographolide on the radiosensitivity of esophageal cancer cells. Immunofluorescence was employed to examine Bax expression. The changes in cell cycle distribution and apoptosis were assayed using flow cytometry. The expression of NF‐κb/Cleaved‐Caspase3/Bax/Bcl‐2 was measured using Western blot analysis. DNA damage was detected via γ‐H2AX foci counting. With a clear dose and time effects, andrographolide was found to inhibit the proliferation of esophageal cell line ECA109. The results of the clonogenic survival assay show that andrographolide could markedly enhance radiosensitivity (P < 0.05) with a sensitizing enhancement ratio of 1.28. Andrographolide caused a dose‐dependent increase in Cleaved‐Caspase3/Bax protein expression and a decrease in Bcl‐2/NF‐κb expression. Apoptosis in andrographolide‐treated ECA‐109 increased significantly compared with the apoptosis in the simple drug and radiation combined with drug groups (P < 0.001; P < 0.05). Moreover, compared with the independent radiation group, the andrographolide combined with radiation group increased the number of DNA double chain breaks. Andrographolide can increase the radiosensitivity of esophageal cell line ECA109. This result may be associated with the decrease in the NF‐κb level and the induced apoptosis of esophageal cancer cells.