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81.
目的探讨miR-155对人大肠癌细胞侵袭能力的影响。方法大肠癌Lovo细胞分为3组:脂质体介导反义miR-155(AS-miR-155)组、无义寡脱氧核苷酸(ODN)组和对照组。测定荧光素酶活性验证3组细胞中miR-155的表达,采用Matrigel基质生长试验检测细胞生长情况,以Transwe Ⅱ方法检测细胞的侵袭力,结果与对照组和无义ODN组比较,转染AS-miR-155组Lovo细胞miR-2l表达水平降低;Matrigel基质生长试验显示,转染AS-miR-155组Lovo细胞体外培养克隆平均直径较小,Transwe Ⅱ细胞侵袭试验显示转染AS-miR-155组穿膜细胞数较少。结论 miR-2l高表达可促进Lovo大肠癌细胞侵袭生长,提示miR-155可以作为基因治疗大肠癌的候选靶点。 相似文献
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目的 预测并验证小鼠mmu-miR-294调控的靶基因,探讨其在肺癌发生发展中的生物学功能.方法 生物信息学预测mmu-miR-294可能调控的靶基因金属蛋白酶(MMP3),双荧光素酶检测验证mmu-miR-294调控MMP3的真实性;脂质体2000介导转染mmu-miR-294模拟物进入Lewis(LLC)细胞株,通过Transwell实验检测细胞侵袭、迁移能力的改变.结果 重组质粒经XbaⅠ单酶切能获得约5000 bp和100 bp的酶切片段,阳性克隆测序,双荧光素酶报告基因检测证明合成寡核苷酸链序列插入正确;脂质体2000介导转染mmu-miR-294模拟物,过表达实验组MMP3蛋白水平较对照组明显降低.转染mmu-miR-294模拟物后LLC细胞的侵袭迁移能力显著降低(P<0.01).结论 低表达mmu-miR-294有助于维持LLC的侵袭转移特性,增加其表达水平可以有效抑制LLC的侵袭迁移能力.mmu-miR-294可能通过调控其靶基因MMP3表达而发挥功能. 相似文献
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Nerea Matamala Beatriz Lara Gema Gómez-Mariano Selene Martínez Irene Vázquez-Domínguez Álvaro Otero-Sobrino Antonio Muñoz-Callejas Elena Sánchez Cristina Esquinas Ana Bustamante Sergio Cadenas Sergio Curi Lourdes Lázaro María Teresa Martínez Esther Rodríguez Marc Miravitlles María Torres-Duran Inés Herrero Beatriz Martínez-Delgado 《Archivos de bronconeumologia》2021,57(7):457-463
IntroductionAlpha-1 antitrypsin deficiency (AATD) is a genetic condition resulting in lung and liver disease with a great clinical variability. MicroRNAs have been identified as disease modifiers; therefore miRNA deregulation could play an important role in disease heterogeneity. Members of miR-320 family are involved in regulating of multiple processes including inflammation, and have potential specific binding sites in the 3′UTR region of SERPINA1 gene. In this study we explore the involvement of miR-320c, a member of this family, in this disease.MethodsFirstly in vitro studies were carried out to demonstrate regulation of SERPINA1 gene by miR-320. Furthermore, the expression of miR-320c was analyzed in the blood of 98 individuals with different AAT serum levels by using quantitative PCR and expression was correlated to clinical parameters of the patients. Finally, HL60 cells were used to analyze induction of miR-320c in inflammatory conditions.ResultsOverexpression of miR-320 members in human HepG2 cells led to inhibition of SERPINA1 expression. Analysis of miR-320c expression in patient's samples revealed significantly increased expression of miR-320c in individuals with pulmonary disease. Additionally, HL60 cells treated with the pro-inflammatory factor lipopolysaccharide (LPS) showed increase in miR-320c expression, suggesting that miR-320c responds to inflammation.ConclusionOur findings demonstrate that miR-320c inhibits SERPINA1 expression in a hepatic cell line and its levels in blood are associated with lung disease in a cohort of patients with different AAT serum levels. These results suggest that miR-320c can play a role in AAT regulation and could be a biomarker of inflammatory processes in pulmonary diseases. 相似文献
86.
《Injury》2018,49(8):1497-1503
AimsThe aim of the study was to test if the addition of CGF to the Masquelet technique contributes to the quality of the membrane formed surrounding the polymethylmethacrylate (PMMA), in terms of inflammation, proliferation and vasculazition in the Masquelet technique in the early and late phases in a rabbit model.Materials and methodsA critical bone defect of 15 mm was created in radius diaphysis, leaving 3 cm of intact bone to the joint. To mimic the Masquelet technique and to increase stability, a 6-hole 1.5 mm plate with two screws was applied, although it was initialy stable because of the inherently fixed ulna and radius both proximally and distally in the rabbits. Group 1 and Group 3, were soleley treated with the Masquelet technique as control groups, and were sacrificed at 3 and 6 weeks, respectively. Group 2 and Group 4, were treated with the Masquelet technique + CGF prepared from the rabbit blood groups, and were sacrificed at 3 and 6 weeks, respectively. The groups were compared histopathologically and immunohistochemically, in respect of the means of thickness of the membrane and ratio of elastic fibers, membrane vascularization (CD31), inflammation (MAC387), proliferation (Ki67), and presence of stem cells (STRO-1).ResultsThickness of the membrane and CD31 values were significantly higher in Group 4 than Group 3 (p = 0.004 for both). MAC387 was statistically significantly higher in Group 2 compared to Group 1 and Group 4 compared to Group 3 (p = 0.04 for both). Ki67 was significantly higher in Group 2 compared to Group 1 and Group 4 compared to Group 3 (p = 0.05 and p = 0.006, respectively). Proliferation in the membrane was statistically significantly higher in Group 2 compared to Group 1 (p = 0.05). Likewise, the proliferation index of Group 4 was statistically significantly higher than Group 3 (p = 0.06). STRO-1 was significantly higher in Group 2 compared to Group 1 (p = 0036).ConclusionThe addition of CGF to the Masquelet technique contributes to the quality of the membrane formed, in respect of inducing inflammation and proliferation, maintaining vascularization on large diaphyseal bone defects, and increasing the number of stem cells. 相似文献
87.
Naibijiang Maolakuerban Baihetiya Azhati Hamulati Tusong Asimujiang Abula Anniwaer Yasheng 《Cancer biology & therapy》2018,19(4):282-291
In this study, we investigated the mechanism of miR-200c-3p and SLC6A1 in regulating cell activity of clear cell renal cell carcinoma (CCRCC). The mRNA and miRNA expressions of tissue specimens were analyzed by CapitalBio Corporation (Beijing, China). The expression of SLC6A1 in CCRCC cells was examined through qRT-PCR and western blot. The migration and invasion ability of 786-O cells was testified by transwell assay after transfected. 786-O cell proliferation ability was detected by MTT assay. Dual luciferase reporter assay verified the association between SLC6A1 and miR-200c-3p. SLC6A1 was high expressed and miR-200c-3p was low expressed in CCRCC tissues and cells. Besides, lower SLC6A1 expression indicated longer survival time and higher survival rate. MiR-200c-3p could directly target at SLC6A1 and reduce its expression. MiR-200c-3p inhibited the proliferation, migration and invasion in 786-O cells by down-regulating SLC6A1 expression. The results suggested that the miR-200c-3p served as a suppressor for CCRCC via down-regulating SLC6A1. 相似文献
88.
Amit Kumar Pandey Yanzhou Zhang Siting Zhang Ying Li Greg Tucker-Kellogg Henry Yang Sudhakar Jha 《Oncotarget》2015,6(38):41290-41306
MicroRNAs (miRNAs) are 22- to 24-nucleotide, small, non-coding RNAs that bind to the 3′UTR of target genes to control gene expression. Consequently, their dysregulation contributes to many diseases, including diabetes and cancer. miR-22 is up-regulated in numerous metastatic cancers and recent studies have suggested a role for miR-22 in promoting stemness and metastasis. TIP60 is a lysine acetyl-transferase reported to be down-regulated in cancer but the molecular mechanism of this reduction is still unclear. In this study, we identify TIP60 as a target of miR-22. We show a negative correlation in the expression of TIP60 and miR-22 in breast cancer patients, and show that low levels of TIP60 and high levels of miR-22 are associated with poor overall survival. Furthermore, pathway analysis using high miR-22/low TIP60 and low miR-22/high TIP60 breast cancer patient datasets suggests association of TIP60/miR-22 with epithelial-mesenchymal transition (EMT), a key alteration in progression of cancer cells. We show that blocking endogenous miR-22 can restore TIP60 levels, which in turn decreases the migration and invasion capacity of metastatic breast cancer cell line. These results provide mechanistic insight into TIP60 regulation and evidence for the utility of the combination of TIP60 and miR-22 as prognostic indicator of breast cancer progression. 相似文献
89.
CD31 is a standard immunostain for evaluating vascular lesions of the skin, but CD31 reactivity for histiocytes is reported in only a small variety of pathological conditions. CD68 and CD163 are well recognized stains for cutaneous histiocytic lesions. We compared immunostaining of CD31 within that of CD68 and CD163 in five cases each of cutaneous lesions containing histiocytes: healing biopsy site, granuloma annulare, xanthogranuloma, ruptured follicular cyst and sarcoidosis. Reactivity was graded on a scale of 0–3 for brightness of immunostaining. Immunoreactivity was seen in histiocytes in all specimens for CD31, CD68 and CD163. The average intensity of staining was 1.7–2.5 for CD31, 2.6–3 for CD68 and 2.9–3 for CD163. The staining was somewhat less for CD31 because the reactivity is localized on the cell surfaces, whereas CD68 and CD163 react with cell surfaces and cytoplasm. We conclude that histiocytes in cutaneous lesions stain for CD31 and the staining is comparable to, but less intense, than that seen with CD68 and CD163. Caution is suggested in interpretation of CD31 staining in skin specimens, as CD31 shows reactivity with histiocytes as well as endothelial cells. 相似文献
90.
Green tea prevents vascular disturbs and attenuates periodontal breakdown in long‐term hyperglycaemia in T1D rats 下载免费PDF全文