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991.
目的 探讨富含亮氨酸重复序列免疫球蛋白样蛋白3(LRIG3)基因过表达对人神经母细胞瘤细胞系SK-N-MC细胞生物学行为的影响。方法 体外培养人神经母细胞瘤细胞系SK-N-MC细胞,分成空白对照组(A组,不转染任何载体或质粒)、载体组(B组,转染载体)和LRIG3过表达组(C组,转染含LRIG3基因过表达质粒)。 荧光定量PCR和免疫印迹法检测LRIG3、Caspase-3和Caspase-9的mRNA和蛋白表达水平。Transwell试剂盒检测细胞侵袭能力,AV-PI试剂盒检测细胞凋亡水平,CCK-8试剂盒检测细胞增殖能力。结果 C组Caspase-3和Caspase-9的mRNA和蛋白表达水平以及细胞凋亡率明显高于A组和B组(P<0.05),细胞增殖率和细胞侵袭能力明显低于A组和B组(P<0.05),而A组和B组之间均无统计学差异(P>0.05)。结论 LRIG3过表达可以抑制人神经母细胞瘤细胞系SK-N-MC细胞增殖和侵袭,促进其凋亡,其机制可能与促进Caspase-3和Caspase-9表达有关 相似文献
992.
993.
Yanyan Cui Dawei Yang Wenjie Wang Luyu Zhang Hongtao Liu Shanshan Ma Wenna Guo Minghao Yao Kun Zhang Wencai Li Yanting Zhang Fangxia Guan 《Molecular carcinogenesis》2020,59(8):940-954
Esophageal squamous cell carcinoma (ESCC) is a common malignant tumor with poor prognosis. And different individuals respond to the same drug differently. Increasing evidence has confirmed that metabolism reprogramming was involved in the drug sensitivity of tumor cells. However, the potential molecular mechanism of 5-fluorouracil (5-FU) sensitivity remains to be elucidated in ESCC cells. In this study, we found that the 5-FU sensitivity of TE1 cells was lower than that of EC1 and Eca109 cells. Gas chromatography-mass spectrometry analysis results showed that nicotinate and nicotinamide metabolism and tricarboxylic acid cycle were significantly different in these three cell lines. Nicotinamide N-methyltransferase (NNMT), a key enzyme of nicotinate and nicotinamide metabolism, was significantly higher expressed in TE1 cells than that in EC1 and Eca109 cells. Therefore, the function of NNMT on 5-FU sensitivity was analyzed in vitro and in vivo. NNMT downregulation significantly increased 5-FU sensitivity in TE1 cells. Meanwhile, the glucose consumption and lactate production were decreased, and the expression of glycolysis-related enzymes hexokinase 2, lactate dehydrogenase A, and phosphoglycerate mutase 1 were downregulated in NNMT knockdown TE1 cells. Besides, overexpression of NNMT in EC1 and Eca109 cells caused the opposite effects. Moreover, when glycolysis was inhibited by 2-deoxyglucose, the roles of NNMT on 5-FU sensitivity was weakened. In vivo experiments showed that NNMT knockdown significantly increased the sensitivity of xenografts to 5-FU and suppressed the Warburg effect. Overall, these results demonstrated that NNMT decreases 5-FU sensitivity in human ESCC cells through promoting the Warburg effect, suggesting that NNMT may contribute to predict the treatment effects of the clinical chemotherapy in ESCC. 相似文献
994.
995.
Jie Qian Wei Nie Jun Lu Lele Zhang Yanwei Zhang Bo Zhang Shuyuan Wang Minjuan Hu Jianlin Xu Yuqing Lou Yu Dong Yanjie Niu Bo Yan Runbo Zhong Wei Zhang Tianqing Chu Hua Zhong Baohui Han 《International journal of cancer. Journal international du cancer》2020,146(11):3124-3133
This study aimed to compare the differences in characteristics and prognoses between Asian and white patients receiving immunotherapy for nonsmall cell lung cancer (NSCLC). We studied 390 patients who received atezolizumab as part of the POPLAR or OAK trial, and analyzed the differences in baseline characteristics, outcomes and genetic mutations in blood samples between Asian and white patients. Overall survival (OS) was longer in Asian compared to white patients (median OS: 18.7 vs. 11.1 months; p = 0.005). Race was identified as an independent prognostic factor for OS (Asian vs. white: hazard ratio 0.647, 95% confidence interval 0.447–0.936, p = 0.021), together with performance status, histology, baseline sum of the longest tumor diameters (BLSLD) and number of metastatic sites. The two groups also differed in terms of characteristics including smoking history, BLSLD, epidermal growth factor receptor (EGFR) mutation frequency, programmed death-ligand 1 expression and blood-based tumor-mutation burden. Blood mutations of STK11, EGFR, KEAP1, POLE, GRM3, ATM and STAG2 were associated with treatment response, and TP53, KEAP1, APC, RB1, CREBBP, EPHA5 and STAG2 mutations were associated with OS. The blood-based mutation profiles differentiated between Asian and white patients, especially in relation to EGFR (23.8 vs. 8.5%), TP53 (30.2 vs. 46.9%) and STK11 (1.6 vs. 12.3%) mutations (all p < 0.05). The different clinicopathological features and mutation profiles in Asian and white patients may explain the superior outcome following atezolizumab treatment in Asian patients with NSCLC. The results of this study have important implications for further studies on racial disparities in relation to immunotherapy. 相似文献
996.
背景与目的:结直肠癌(colorectal cancer,CRC)为世界第三常见恶性肿瘤,近年来研究者认为白细胞介素(interleukin,IL)-35和(或)IL-37与CRC的发展有关,但其作用机制尚未阐明。探究IL-35和IL-37在CRC发展中的作用及其可能的机制,分析IL-35和IL-37与CRC患者预后的相关性。方法:收集2013年—2017年在上海交通大学医学院附属同仁医院接受治疗的191例CRC患者手术病理蜡块的肿瘤组织,与其匹配的非癌组织是来源于同一患者的肠癌手术切缘蜡块组织。应用免疫组织化学(immunohistochemistry,IHC)染色法将CRC患者的癌组织与非癌组织染色,并运用Image-Pro Plus将IHC染色阳性部分定量分析,结合随访结果,探讨癌组织与非癌组织中IL-35和IL-37的表达水平与CRC临床病理学特征及预后的相关性。结果:与非癌组织相比,CRC组织中IL-35的表达量减少了50%(P<0.000 1)。CRC组织中IL-37的表达量与非癌组织相比增加了40%(P=0.012)。多因素生存分析显示,癌组织中IL-35(HR=0.39;95% CI:0.16~0.97;P=0.04)的表达水平是CRC患者术后生存的独立预测指标。结论:IL-35和IL-37蛋白的表达水平可能与CRC的发展有关,IL-35的表达水平可能是CRC患者术后生存的独立预测指标。 相似文献
997.
目的:研究在鼻咽癌放射治疗中应用发泡胶进行体位固定对剂量分布的影响。方法:随机选取11例应用头颈肩热塑膜联合发泡胶进行体位固定的鼻咽癌患者,在Pinnacle计划系统中将空白CT值设置到发泡胶的CT值以下,以确保发泡胶的CT值被计算在内,作为第一组计划(Plan_F)。同时,复制第一组计划并在定位图像上勾画出发泡胶,设置发泡胶的CT值为0,在不改变射野分布、权重及计划跳数的情况下重新计算剂量分布,作为第二组计划(Plan_N)。比较两组计划的靶区及周围正常组织的剂量分布。结果:对于靶区(GTVnx、GTVnd、GTVrpn、PGTVnx、CTV1、PTV1、CTV2、PTV2)的最小剂量Dmin,最大剂量Dmax,平均剂量Dmean去除发泡胶之后,所测 255组数据中仅有6组数据出现减小(约占2.4%),Dmin、Dmax和Dmean的变化度(%)(X±SD)依次为0.215±0.969、 0.395±0.623和 0.442±0.178,其中除了GTVrpn的Dmin(P=0.727)和Dmax(P=0.142),PGTVnx的Dmin(P=0.623),CTV1 Dmin(P=0.713),CTV2 Dmax(P=0.066),其他评估指标皆显示发泡胶使用组剂量低于去除发泡胶组(P<0.05);而对于周围正常组织(脑干、脊髓、左右晶体、左右视神经和腮腺)的Dmean和Dmax去除发泡胶之后,所测的154组数据中仅有14组数据出现减小(约占9.1%),Dmax和Dmean的变化度(%)(X±SD)依次为0.194±0.192 和0.129±0.128,其中除了左、右晶体的平均剂量Dmean(P值分别为0.123和0.06),其余各项指标同样显示发泡胶使用组剂量低于去除发泡胶组(P<0.05)。结论:发泡胶的使用降低了实际治疗过程中受照部位的剂量,但发泡胶对剂量变化的影响都在目前临床可接受的范围之内。 相似文献
998.
Kun Ma Jiayun Liu Youjin Wang Yubin Zhong Zhenfeng Wu Ruiying Fan Shanfeng Guo 《Journal of gastrointestinal oncology.》2020,11(6):1350
BackgroundOur study aims to investigate changes in cell-free DNA (cfDNA) concentration and integrity in primary hepatocellular carcinoma (PHC) patients before and after transcatheter arterial chemoembolization (TACE) treatment and their influence on the evaluation of prognosis of the disease.MethodsA total of 84 PHC patients admitted to the Affiliated Hospital of Nanjing University of Chinese Medicine from December 2016 to December 2017 were included as the study group, while 55 healthy people served as the control group. Plasma cfDNA concentration and integrity were determined using qRT-PCR. The correlation between cfDNA concentration/integrity and clinical characteristics of PHC patients were analyzed. A ROC curve was used to investigate the sensitivity and specificity of cfDNA as detection indices. Univariate and multivariate analyses were used to analyze factors affecting recurrence in PHC patients and compare recurrence-free survival (RFS) of PHC patients with high cfDNA expression and low cfDNA expression.ResultsPlasma cfDNA concentration and integrity were significantly higher in PHC patients before TACE treatment than in healthy people and significantly lower after treatment than before (P<0.05). The cfDNA concentration was significantly correlated with tumor size, lymph node metastasis, TNM stage, and BCLC stage, while cfDNA integrity was significantly correlated with tumor size, TNM stage, and BCLC stage (P<0.05). ROC results showed that the area under the curve (AUC) value of cfDNA concentration was the largest, with an optimal cut-off of 10.51 ng/mL. Multivariate regression analysis for COX showed that the TNM stage, cfDNA concentration, and AFP were independent risk factors that affected PHC patients’ survival.ConclusionsPlasma cfDNA concentration in PHC patients is more sensitive and specific than any other tumor marker. It is an independent risk factor for PHC patients treated with TACE. Therefore, it is hypothesized cfDNA is a potential biomarker for prognostic evaluation of PHC patients treated with TACE. 相似文献
999.
北京地区25年来消化性溃疡及胃癌发病情况的演变 总被引:13,自引:0,他引:13
目的探讨25年来十二指肠球部溃疡(DU)、胃溃疡、胃癌及幽门螺杆菌(Hp)感染在胃镜检查中发生的改变。方法分析1980年1月至2004年12月于我院进行胃镜检查的所有病例,共计104987例。选择全部DU、胃溃疡、经病理证实的胃癌病例为研究对象,分为10~<20岁、20~<30岁、30~<40岁、40~<50岁、50~<60岁、60~<70岁、70~<80岁及≥80岁8个年龄组。结果DU共13684例,平均检出率为13.03%,1999年以后呈下降趋势;胃溃疡共4398例,平均检出率为4.19%,1996年以后呈下降趋势;胃癌共1732例,检出率波动于1.02%~2.36%之间,平均为1.68%,无明显变化。检出DU、胃溃疡、胃癌的平均年龄1980年时分别为39.9岁、47.2岁和55.5岁,2004年分别为43.3岁、55.2岁和61.1岁,其平均年龄均呈上升趋势。Hp的平均检出率为43.54%,1995年以后呈下降趋势。结论DU、胃溃疡、胃癌的检出年龄呈上升趋势;DU、胃溃疡及Hp的检出率近年呈下降趋势,胃癌的检出率无明显变化。 相似文献
1000.
急性心肌梗死伴2型糖尿病患者内皮祖细胞动员障碍 总被引:1,自引:1,他引:1
目的观察急性心肌梗死伴2型糖尿病患者血浆缺血相关因子血管内皮生长因子和基质细胞衍生因子水平,骨髓内皮祖细胞动员是否存在障碍,以及基质细胞衍生因子、血管内皮生长因子-内皮祖细胞动员通路是否存在异常。方法采用密度梯度离心法分离外周血单个核细胞,用流式细胞仪检测急性心肌梗死后不同时间点(1、3、5、7、14和28天)外周血CD45-/low /CD34 /CD133 /KDR 早期内皮祖细胞数量。酶联免疫吸附法检测血浆中血管内皮生长因子、基质细胞衍生因子以及高敏C反应蛋白的浓度。结果急性心肌梗死伴2型糖尿病患者外周血内皮祖细胞动员高峰(第7天)较急性心肌梗死非糖尿病患者(第5天)延迟且显著减少[(140±48)/106比(246±100)/106,P<0.05]。糖尿病组血浆血管内皮生长因子(第5天:277±95ng/L比168±35ng/L,P<0.05)、基质细胞衍生因子(第5天:3835±402ng/L比3287±384ng/L,P<0.05)以及高敏C反应蛋白(第3天:55.55±14.88mg/L比36.92±14.83mg/L,P<0.05)在高峰点的水平显著高于非糖尿病组。结论糖尿病患者心肌梗死后组织缺血程度较重,但组织缺血后基质细胞衍生因子、血管内皮生长因子-内皮祖细胞动员通路存在障碍,这可能是糖尿病患者缺血后血管新生功能障碍,发生急性心肌梗死后预后较差的原因之一。 相似文献