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51.
miR-183, a member of an evolutionarily conserved miRNA cluster (miR-96, miR-182, and miR-183), has been demonstrated to act as both a tumor suppressor and oncogene in various type of human cancer. However, the biological role of miR-183 in gastric cancer (GC) still remains unclear. In the present study, miR-183 expression was significantly decreased in gastric cancer tissues compared with its’ adjacent normal tissues, and down-regulation of miR-183 was significantly associated with lymph node metastasis and pathological TNM stage. Furthermore, Erzin, which was reported to be up-regulated in gastric cancer, was identified as an efficient target of miR-183. Overexpression of miR-183 markedly suppressed cells invasion by downregulation of Ezrin expression. However, miR-183 expression didn’t affect cells proliferation and cell cycle distribution of GC. In conclusion, our study demonstrated that miR-183 acts as a tumor suppressor in GC, partially at least via regulation of Ezrin. Therefore, miR-183 may be a potential target for the treatment of gastric cancer.  相似文献   
52.
Recent studies have highlighted the role of microRNA-21 (miR-21) as a prognostic biomarker of breast cancer. However, controversy still remains. The present study aimed to summarize available evidences and obtain a more precise estimation of a prognostic role of miR-21 in breast cancer patients. All eligible studies were searched from PubMed and EMBASE through multiple search strategies. Data were extracted from studies comparing survival in breast cancer patients having higher miR-21 expression with those having lower expression. A meta-analysis was performed to clarify prognostic role of miR-21 in patients with breast cancer. Subgroup analysis was also performed according to patients’ ethnicity. A total of 6 eligible articles comprising 951 cases were selected for this meta-analysis. The combined hazard ratios (HRs) and 95% confidence intervals (95% CIs) for overall survival (OS) were 2.11 (1.09-4.08) and for disease free survival (DFS) was 1.6 (1.30-1.96). Subgroup analysis indicated high miR-21 expression was significantly associated with worse OS in Asian patients (HR = 4.39, 95% CI: 2.47-7.80) but not in non-Asian patients (HR = 1.18, 95% CI: 0.81-1.70). Sensitivity analysis revealed results of this meta-analysis were robust. Odds ratios (ORs) showed that miR-21 expression was closely associated with estrogen receptor (ER), progesterone receptor (PR), lymph node metastasis, histological grade, Her2/neu. The pooled ORs and 95% CIs were 0.53 (0.35-0.80), 0.49 (0.32-0.74), 2.32 (1.54-3.50), 2.44 (1.58-3.75), 4.29 (2.34-7.85), respectively. Our results indicated that elevated miR-21 expression could potentially predict poor survival in patients with breast cancer.  相似文献   
53.
目的:探讨急性T淋巴细胞白血病(T-ALL)患儿外周血单个核细胞(PBMNC)中miR-146a和miR-221表达水平及临床意义。方法:选取海南省第三人民医院收治的初诊T-ALL患儿130例(T-ALL组)和体检健康者50例(对照组)。T-ALL患儿以治疗前作为初发组,诱导治疗d 33达完全缓解者作为缓解组(n=98),未完全缓解者作为难治组(n=32)。采用实时荧光定量PCR方法检测各组PBMNC的miR-146a及miR-221表达水平。ROC曲线分析miR-146a及miR-221对T-ALL的诊断价值,Pearson相关分析评价T-ALL患儿miR-146a及miR-221表达与白细胞计数的相关性。结果:T-ALL组PBMNC的miR-146a及miR-221表达水平均明显高于对照组(5.83±1.54 vs 0.96±0.17)(7.13±2.60 vs 1.64±0.51)(P<0.01)。难治组PBMNC的miR-146a及miR-221表达水平均明显高于缓解组和初发组(8.74±2.35 vs 1.70±0.63,5.83±1.54)(11.316±4.83 vs 2.62±0.85,7.13±2.60)(P<0.01)。miR-146a及miR-221表达水平与白细胞计数、危险度分型和MRD相关(P<0.05)。ROC曲线分析显示,miR-146a及miR-221诊断T-ALL的最佳截值分别为3.90和5.28,2项联合诊断T-ALL的AUC(95%CI)为0.835(0.764-0.892),其敏感度和特异度分别为85.0%和77.2%。相关分析显示,T-ALL患儿PBMNC的miR-146a及miR-221表达水平与白细胞计数均呈正相关(r=0.705,r=0.653,P<0.01),miR-146a与miR-221呈正相关(r=0.784,P<0.01)。结论:miR-146a及miR-221在T-ALL患儿中表达上调,且与T-ALL患儿预后密切相关,2项联合检测对T-ALL诊断具有一定价值。  相似文献   
54.
目的探讨人结肠癌细胞SW620中细胞周期蛋白1(CCND1)的表达情况及其异常表达对细胞增殖的影响,阐述microRNA-138(miR-138)在SW620增殖中的可能机制。方法采用实时荧光定量聚合酶链式反应(qRT-PCR)以及Western blot确定结肠癌组织和癌旁组织中CCND1的表达情况;随后采用qT-PCR检测结肠癌组织内miR-138的表达,并通过统计学分析miR-138与CCND1表达的相关性,培养SW620细胞并转染miR-138模拟物(mimics)后验证miR-138与CCND1的相关性,在SW620细胞内进一步转染miR-138模拟物后,Transwell和MTT检测不同处理组中细胞增殖和迁移能力的改变情况;继续转染CCND1 siRNA后,探索miR-138影响细胞生物学过程的可能机制。结果结肠癌组织中,与相应癌旁组织相比,CCND1表达显著升高,miR-138表达降低,差异有统计学意义(P<0.05);转染miR-138mimics后,与空白对照组(未转染组)相比,细胞迁徙能力下降,同时增殖降低,差异有统计学意义(P<0.05);转染CCND1 siRNA后,与未转染组相比,miR-138表达变化无显著差异(P>0.05),而细胞侵袭能力和增殖能力较未转染组相比显著改变,差异有统计学意义(P<0.05)。结论结肠癌组织中CCND1异常升高可能与miR-138的表达降低有关,且miR-138影响SW620细胞的迁移和增殖能力可能是通过影响CCND1的表达实现的。  相似文献   
55.
Treatment of liver cancer with regional intraarterial 5-FU infusion.   总被引:1,自引:0,他引:1  
The results of a retrospective three year study of forty-six patients with cancer of the liver treated with regional intraarterial infusion of 5-FU are reported. No primary mortality was noted. Oblective overall remission rate was 43 per cent. Overall median survival from onset of treatment was six months. The one year survival rate was 33 per cent and the two year survival rate 11 per cent. Patients with an objective response had a significantly prolonged survival as compared with nonresponders, especially in the colorectal group: sixteen months versus four months. Survival was not related to tumor size and involvement of the liver. During treatment 42 per cent of the patients developed extrahepatic metastases. Quality of life was improved in 63 per cent of the patients. The results indicate that infusion therapy induces reasonable response and palliation but is inadequate for the control of extrahepatic tumor growth.  相似文献   
56.
Thymic size can be affected by both exogenous and endogenous glucocorticoids. The risk of respiratory distress syndrome is reduced after maternal steroid administration. To find whether fetal lung maturity correlates with size of the thymus, the cardiothymic:thoracic ratio was measured in 167 newborn infants with and without RDS. Mean CT/T was significantly greater (0.40 vs 0.35; P less than 0.001) in those babies with RDS. This relation was independent of gestational age, although an increase in CT/T with advancing gestational age was shown. Prepartum maternal steroid administration did not result in significant involution of the cardiothymic shadow when compared with control infants with and without RDS. The CT/T may be of use in predicting which premature babies are more likely to develop RDS.  相似文献   
57.
In relation to a recent survey of chromosome aberrations in 856 human neoplasms the following points are presented: 1) the chromosome aberrations of significance to the biology of neoplasms are nonrandom; 2) aberrations of a particular chromosome tend to be of similar kind; 3) aberrations cluster to a limited number of specific chromosomes; 4) geographic differences have been observed in chromosome aberrations; 5) the karyotypic pattern of a neoplasm may be influenced by previous exposure to potential carcinogenic agents; 6) the role of chromosome aberrations in neoplasia—a hypothesis; 7) a plea is made for unpublished data to be included in our next survey of chromosome aberrations.  相似文献   
58.
The pattern of heteromorphisms in the C-band-positive constitutive heterochromatin of human chromosomes No. 1, 9, and 16 was studied in peripheral lymphocytes of 45 patients with soft tissue sarcomas and 78 control individuals. The parameters of the heterochromatic regions analyzed were relative size, symmetry-asymmetry within homologous pairs, and incidence of inversions. No consistent differences were found in these parameters between controls and sarcoma patients.  相似文献   
59.
A method for chromosome analysis of malignant cells by means of fine needle aspiration biopsy has been developed. The method has some obvious advantages compared to conventional surgical biopsy. During a 1-year period 25 consecutive non-Hodgkin, non-Burkitt lymphoma biopsies from 19 patients have been studied. In 14 out of 21 lymph node biopsies chromosome analysis was successful; whereas, four biopsies of subcutaneous lymphomas were unsuccessful.  相似文献   
60.
姚怡 《海南医学》2011,22(16):113-115
MicroRNAs (miRNAs)是长度约22个核苷酸左右的内源性、非编码RNA.在心血管疾病状态下,如增殖性血管疾病,心脏肥大,心功不全和缺血性心脏病的心血管组织中,miRNA-21表达下调.miRNA-21在血管平滑肌细胞的增殖、凋亡,心肌细胞生长、死亡及心肌细胞纤维化方面起着重要作用,已被证实参与上述疾病发病过...  相似文献   
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