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991.
993.
目的:通过筛选与膀胱癌生存预后相关的非编码小分子核糖核酸(microRNAs,miRNAs),构建风险预后模型评价患者预后。方法:从人类癌症基因图谱(The Cancer Genome Atlas,TCGA)数据库下载膀胱癌miRNAs与mRNAs数据及对应的临床相关信息,筛选差异的miRNAs和mRNAs。对差异的miRNAs进行Kaplan-Meier(K-M)生存分析和单因素Cox回归分析评价筛选得到与预后相关的miRNAs。采用多因素Cox回归进一步分析获得风险模型目标miRNAs,建立最佳风险预后模型,评价模型效能。通过在线数据库和差异mRNAs数据对结合的miRNA靶基因进行筛选,然后进行KEGG和GO富集分析,预测miRNAs靶基因功能。结果:筛选得到膀胱癌差异miRNAs有473个,差异mRNAs有7 106个。运用K-M生存分析及单因素Cox回归筛选得到24个与膀胱癌患者生存预后相关的miRNAs,进一步通过多因素Cox回归得到11个与风险预后模型紧密相关的miRNAs,成功构建miRNAs风险预后模型。模型风险评分=(-0.4×Exphsa-miR-145-5p)+(-0.928×Exphsa-miR-99a-5p)+(-0.295×Exphsa-miR-7705)+(-0.566×Exphsa-miR-590-3p)+(0.201×Exphsa-miR-337-3p)+(0.576×Exphsa-miR-125b-2-3p)+(0.345×Exphsa-miR-652-3p)+(-0.718×Exphsa-miR-143-5p)+(0.286×Exphsa-miR-3065-3p)+(0.282×Exphsa-let-7c-3p)+(0.145×Exphsa-miR-216a-5p)。模型的受试者工作特征曲线(receiver operating characteristic curve,ROC)曲线下面积(the area under the ROC curve,AUC)为0.781,提示风险预后模型具有较好的预测效能。K-M生存分析提示模型评分越高的患者5年生存率越低。GO和KEGG富集分析显示,模型miRNAs能够调控多种泌尿系统活性信号和相关通路,介导膀胱癌疾病进展。结论:成功构建膀胱癌miRNAs风险预后评估模型,为临床膀胱癌患者生存预测提供了一定的价值。 相似文献
994.
Karim Abid Maja Beck Popovic Katia Balmas Bourloud Jacqueline Schoumans Joana Grand-Guillaume Eric Grouzmann Annick Mühlethaler-Mottet 《Oncotarget》2021,12(1):49
Metanephrines (MNs; normetanephrine (NMN), metanephrine (MN) and methoxytyramine (MT)) detected in urine or plasma represent the best biomarker for neuroblastoma (NB) diagnosis, however the metabolism of both catecholamine (CAT) and MNs remains enigmatic in NB. Using patient-derived xenograft (PDX) models derived from primary NB cells, we observed that the plasma levels of MNs in NB-PDX-bearing mice were comparable as in patients. Interestingly, murine plasma displayed an elevated fraction of glucuronidated forms of MNs relative to human plasma where sulfonated forms prevail. In tumors, the concentration ranges of MNs and CAT and the expression levels of the main genes involved in catecholamine metabolism were similar between NB-PDX and human NB tissues. Likewise, plasma and intratumoral profiles of individual MNs, with increased levels of MT and NMN relative to MN, were also conserved in mouse models as in patients. We further demonstrated the downregulation of the Phenylethanolamine N-Methyltransferase gene in NB biopsies and in NB-PDX explaining this biochemical phenotype, and giving a rational to the low levels of epinephrine and MN measured in NB affected patients. Thus, our subcutaneous murine NB-PDX models not only reproduce the phenotype of primary NB tumors, but also the metabolism of catecholamine as observed in patients. This may potentially open new avenues in preclinical studies for the follow up of novel therapeutic options for NB through the quantification of plasma MNs. 相似文献
995.
996.
目的 探究四维(4D)超声对运动靶体积分辨能力。方法 选用前列腺超声模型,分组对比研究应用4D超声在不同运动振幅(A)及运动周期(T)下勾画前列腺靶区,模拟A值分别设置为0.5、1.0、2.0、3.0、4.0、5.0 mm,t值设为1、2、3、4s。分别计算模体前列腺靶体积,并以靶区静止时超声图像作为对照,分析两者间差异。结果 模体静止时超声靶体积与CT靶体积大小有较高一致性(P>0.05)。A值为0.5、1.0 mm,t值为1~4s时的体积与静止时超声靶体积相近(均P>0.05);A值为2.0、3.0 mm,t值为1~3s时靶体积与静止时超声靶体积不同(均P<0.05)。A值为2.0 mm,t值为4s时靶体积与静止时超声靶体积相近(P=0.710),组内极差为6.7cm3,标准差为1.15cm3;A值为3.0 mm,t值为4.0s时靶体积重复性差,组内极差为14.4cm3;A值为4.0、5.0 mm,t值为1~4s时组内极差分别为3.27~17.63cm3、6.51~21.02cm3。各周期下靶体积重复性很差,不能满足临床要求。结论 4D维超声可在患者运动周期1~4s内、运动幅度≤1 mm内为患者靶区勾画提供可靠参考数据,探头初始位置无影响。 相似文献
997.
Lulu Zhao Weili Han Xisheng Yang Dongbing Zhao Penghui Niu Xianchun Gao Zhenkun Wu Xiaojie Zhang Zefeng Li Gang Ji Yingtai Chen 《Cancer science》2021,112(8):3266-3277
The argument concerning the exact minimum number of examined lymph nodes (ELNs) has continued for a long time among various regions, and no consensus has been reached for stratified pathological T stages for data to date. Data from 4607 pN0 patients with gastric cancer were analyzed. Kaplan-Meier analysis showed the similar overall survival (OS) outcomes among the 3 groups (ELNs ≤ 15, 16 ≤ ELNs ≤ 29 and ELNs ≥ 30, P = .171). However, the ELNs ≥ 30 group had a better disease-free survival (DFS) outcome compared with the others (all P < .05). An increased ELN group (ELNs ≥ 30) showed an improved OS only for pT3 patients (hazard ratio [HR] = 0.397, 95% confidence interval (CI): 0.182-0.866, P = .020), while an improved DFS for pT3 patients (HR = 0.362, 95%CI: 0.152-0.860, P = .021) and pT4 patients (HR = 0.484, 95%CI: 0.277-0.844, P = .011) in the multivariate analysis. A well discriminated and calibrated nomogram was constructed to predict the probability of the OS and DFS, with the C-index for OS and DFS prediction of 0.782 (95%CI: 0.735 to 0.829) and 0.738 (95%CI: 0.685 to 0.791), respectively. This study provides new and useful insights into the impact of ELN count on reducing stage migration and postoperative recurrence of pN0 patients with gastric cancer in 2000-2017. In conclusion, a larger number of ELNs is suggested for surgeons to prolong the prognosis of pN0 gastric cancer, especially for pT3 patients. 相似文献
998.
Yang Liu Bing Xin Masahiro Yamamoto Masanori Goto Takako Ooshio Yuki Kamikokura Hiroki Tanaka Lingtong Meng Yoko Okada Yusuke Mizukami Yuji Nishikawa 《Cancer science》2021,112(8):3111-3124
The two principal histological types of primary liver cancers, hepatocellular carcinoma (HCC) and cholangiocarcinoma, can coexist within a tumor, comprising combined hepatocellular-cholangiocarcinoma (cHCC-CCA). Although the possible involvement of liver stem/progenitor cells has been proposed for the pathogenesis of cHCC-CCA, the cells might originate from transformed hepatocytes that undergo ductular transdifferentiation or dedifferentiation. We previously demonstrated that concomitant introduction of mutant HRASV12 (HRAS) and Myc into mouse hepatocytes induced dedifferentiated tumors that expressed fetal/neonatal liver genes and proteins. Here, we examine whether the phenotype of HRAS- or HRAS/Myc-induced tumors might be affected by the disruption of the Trp53 gene, which has been shown to induce biliary differentiation in mouse liver tumors. Hepatocyte-derived liver tumors were induced in heterozygous and homozygous p53-knockout (KO) mice by hydrodynamic tail vein injection of HRAS- or Myc-containing transposon cassette plasmids, which were modified by deleting loxP sites, with a transposase-expressing plasmid. The HRAS-induced and HRAS/Myc-induced tumors in the wild-type mice demonstrated histological features of HCC, whereas the phenotype of the tumors generated in the p53-KO mice was consistent with cHCC-CCA. The expression of fetal/neonatal liver proteins, including delta-like 1, was detected in the HRAS/Myc-induced but not in the HRAS-induced cHCC-CCA tissues. The dedifferentiation in the HRAS/Myc-induced tumors was more marked in the homozygous p53-KO mice than in the heterozygous p53-KO mice and was associated with activation of Myc and YAP and suppression of ERK phosphorylation. Our results suggest that the loss of p53 promotes ductular differentiation of hepatocyte-derived tumor cells through either transdifferentiation or Myc-mediated dedifferentiation. 相似文献
999.
Hisanori Isomura Ayumu Taguchi Taisuke Kajino Naoya Asai Masahiro Nakatochi Seiichi Kato Keiko Suzuki Kiyoshi Yanagisawa Motoshi Suzuki Teruaki Fujishita Tomoya Yamaguchi Masahide Takahashi Takashi Takahashi 《Cancer science》2021,112(4):1614-1623
We previously reported that ROR1 is a crucial downstream gene for the TTF-1/NKX2-1 lineage-survival oncogene in lung adenocarcinoma, while others have found altered expression of ROR1 in multiple cancer types. Accumulated evidence therefore indicates ROR1 as an attractive molecular target, though it has yet to be determined whether targeting Ror1 can inhibit tumor development and growth in vivo. To this end, genetically engineered mice carrying homozygously floxed Ror1 alleles and an SP-C promoter–driven human mutant EGFR transgene were generated. Ror1 ablation resulted in marked retardation of tumor development and progression in association with reduced malignant characteristics and significantly better survival. Interestingly, gene set enrichment analysis identified a hypoxia-induced gene set (HALLMARK_HYPOXIA) as most significantly downregulated by Ror1 ablation in vivo, which led to findings showing that ROR1 knockdown diminished HIF-1α expression under normoxia and clearly hampered HIF-1α induction in response to hypoxia in human lung adenocarcinoma cell lines. The present results directly demonstrate the importance of Ror1 for in vivo development and progression of lung adenocarcinoma, and also identify Ror1 as a novel regulator of Hif-1α. Thus, a future study aimed at the development of a novel therapeutic targeting ROR1 for treatment of solid tumors such as seen in lung cancer, which are frequently accompanied with a hypoxic tumor microenvironment, is warranted. 相似文献
1000.
Mayu Shiomi Shinya Matsuzaki Satoshi Serada Koji Matsuo Chihiro Mizuta-Odani Mariko Jitsumori Ruriko Nakae Satoko Matsuzaki Satoshi Nakagawa Kosuke Hiramatsu Ai Miyoshi Eiji Kobayashi Toshihiro Kimura Yutaka Ueda Kiyoshi Yoshino Tetsuji Naka Tadashi Kimura 《Cancer science》2021,112(9):3655-3668
This study aimed to investigate the cytotoxicity of a cluster of differentiation 70 antibody-drug conjugate (CD70-ADC) against ovarian cancer in in vitro and in vivo xenograft models. CD70 expression was assessed in clinical samples by immunohistochemical analysis. Western blotting and fluorescence-activated cell sorting analyses were used to determine CD70 expression in the ovarian cancer cell lines A2780 and SKOV3, and in the cisplatin-resistant ovarian cancer cell lines A2780cisR and SKOV3cisR. CD70 expression after cisplatin exposure was determined in A2780 cells transfected with mock- or nuclear factor (NF)-κB-p65-small interfering RNA. We developed an ADC with an anti-CD70 monoclonal antibody linked to monomethyl auristatin F and investigated its cytotoxic effect. We examined 63 ovarian cancer clinical samples; 43 (68.3%) of them expressed CD70. Among patients with advanced stage disease (n = 50), those who received neoadjuvant chemotherapy were more likely to exhibit high CD70 expression compared to those who did not (55.6% [15/27] vs 17.4% [4/23], P < .01). CD70 expression was confirmed in A2780cisR, SKOV3, and SKOV3cisR cells. Notably, CD70 expression was induced after cisplatin treatment in A2780 mock cells but not in A2780-NF-κB-p65-silenced cells. CD70-ADC was cytotoxic to A2780cisR, SKOV3, and SKOV3cisR cells, with IC50 values ranging from 0.104 to 0.341 nmol/L. In A2780cisR and SKOV3cisR xenograft models, tumor growth in CD70-ADC treated mice was significantly inhibited compared to that in the control-ADC treated mice (A2780cisR: 32.0 vs 1639.0 mm3, P < .01; SKOV3cisR: 232.2 vs 584.9 mm3, P < .01). Platinum treatment induced CD70 expression in ovarian cancer cells. CD70-ADC may have potential therapeutic implications in the treatment of CD70 expressing ovarian cancer. 相似文献