MicroRNA-370 directly targets FOXM1 to inhibit cell growth and metastasis in osteosarcoma cells

MicroRNAs (miRNAs) are endogenous, non-coding, small RNAs, which play a critical role in regulating varieties of the biological and pathologic processes. Several reports have indicated that miR-370 acts as a tumor suppressor in varieties of tumors. However, the roles of miR-370 in osteosarcoma have not been reported. In this study, our objective was to explore the biological functions and its molecular mechanism of miR-370 in osteosarcoma cell lines, finding a therapeutic target of osteosarcoma. Our data demonstrated that miR-370 was evidently reduced in osteosarcoma cell lines, whereas FOXM1 expression was markedly increased. Up-regulation of miR-370 suppressed proliferation, arrested cell cycle and induced apoptosis in osteosarcoma cells. Besides, invasion and EMT of osteosarcoma cells was also inhibited by introduction of miR-370. Next, we found that FOXM1 expression was significantly reduced by up-regulation of miR-370. Bioinformatics analysis predicted that the FOXM1 was a potential target gene of miR-370. Luciferase reporter assay further confirmed that miR-370 could directly target the 3’ UTR of FOXM1. Overexpression of FOXM1 in osteosarcoma cells transfected with miR-370 mimic partially reversed the effects of miR-370. In conclusion, miR-370 inhibited cell growth and metastasis in osteosarcoma cells by down-regulation of FOXM1.     

pH 敏感的 PEG-PAsp（DIP）负载 miR-21-inhibitor 纳米聚合物囊泡的制备及传输在前列腺癌 PC-3细胞中的效应研究

目的：制备以生物纳米材料 pH 敏感嵌段共聚物聚乙二醇-聚天冬氨酸二异丙基氨基乙酯[PEG-PAsp (DIP)]传输 miR-21-inhibitor 聚合物囊泡,初步探讨 pH 敏感聚合物囊泡对前列腺癌细胞的毒性作用及传输效应。方法①通过静电作用,在室温条件下制备 PEG-PAsp (DIP)传输 miR-21-inhibitor 聚合物囊泡;②通过凝胶阻滞实验检测不同浓度下纳米聚合物囊泡(NPs)的复合情况;③通过 CCK-8实验检测不同浓度下 pH 敏感 NPs 对前列腺癌细胞 PC-3的毒性作用;④通过激光共聚焦实验,观察 PEG-PAsp (DIP)/ miR-21-inhibitor 纳米聚合物囊泡进入 PC-3细胞的传输效应。结果实验结果表明： N/ P 为20 PEG-PAsp (DIP)与 miR-21-inhibitor 已完全复合,粒径较小具有一定的正电荷,且对 PC-3细胞毒性较小;通过激光共聚焦实验,成功构建了纳米聚合物囊泡传输进入 PC-3前列腺癌细胞方法。结论成功制备了纳米聚合物囊泡,并初步探讨了纳米聚合物囊泡的表征、体外 PC-3细胞毒性试验与纳米聚合物囊泡结合 miRNA传输于 PC-3细胞的激光共聚焦实验,为下一步阐明反义 miR-21寡核苷酸诱导前列腺癌细胞凋亡的作用和分子机制打好基础。     

miR-580对乳腺癌细胞系中Twist1的调节作用

目的：探讨miR-580在MCF-10A细胞系中对Twist1的调节。方法：本实验利用生物信息学方法预测Twist1的靶miRNA是miR-580。首先,采用qPCR法检测在MCF-10A系列细胞系中Twist1及miR-580的表达。然后,在MCF-10A细胞系中分别转染miR-580类似物和miR-580抑制物后,利用RT-PCR、Western blot、t检验分析Twist1的表达及细胞迁移能力的变化。最后利用荧光素酶实验验证miR-580通过结合在Twist1的3'UTR调节其表达。结果：1)在MCF-10A细胞系中Twist1与miR-580的表达呈负相关;2)在MCF-10A细胞系中转染miR-580类似物后,Twist1的表达下调;在MCF-10A细胞系中转染miR-580抑制物后Twist1的表达上调;3)在MCF-10A细胞系中引入miR-580类似物后细胞迁移能力降低;4)miR-580直接结合在Twist1的3'UTR。结论：miRNA-580在MCF-10A细胞系中通过结合在Twist1的3'UTR负向调节Twist1的表达从而克制细胞的迁移。     

Overexpression of miR-221 inhibits proliferation and promotes apoptosis of human astrocytoma cells

microRNAs (miRNAs) play tumor-promoting roles in a variety of tumors. This study investigated the expression of miRNA-211 (miR-221) in human astrocytoma, and its effect on proliferation and apoptosis of human astrocytoma cells in vitro. miR-221 expression was detected in 10 astrocytoma tissues and 4 adjacent tissues by real-time quantitative PCR (qRT-PCR). miR-221 expression in situ was significantly higher in astrocytoma tissues than in adjacent tissues (P<0.05). To determine whether the upregulation of miR-221 could be associated with tumor development or progression, a synthetic miR-221 mimic was transiently transfected into U251 astrocytoma cells in vitro. qRT-PCR confirmed that the mimic significantly increased the expression of miR-221 in these cells. An MTT colorimetric assay indicated that proliferation was significantly higher in U251 cells transfected with miR-221 mimic than in scramble-transfected control cells (P<0.05). Further analysis of miR-221 transfected cells by flow cytometry revealed an altered cell cycle progression, with more cells in S and G1 phase, as well as an inhibition of apoptosis (P<0.05). These findings indicate that the upregulation of miR-221 in astrocytoma tissues may be associated with development or progression of these tumors. Thus, miR-221 should be explored as a potential molecular marker for the diagnosis and treatment of astrocytoma.     

Targeting miR-21 with AS-miR-21 suppresses aggressive growth of human tongue squamous cell carcinoma in vivo

MicroRNAs (miRNAs) are involved in many human malignant tumors. Notably, miR-21 was identified to contribute to tumorigenicity. To investigate the repressive effect of targeting miR-21 with AS-miR-21 on proliferation of tongue squamous cell carcinoma (TSCC). We established the Tca8113-luc cell line with stable luciferase expression using pGL6-luciferase (pGL6-luc) plasmid transfection. TSCC xenograft models were characterized by high tumorigenicity rate and stable growth. Intratumor injection of Oligofectamine™-mediated AS-miR-21 significantly inhibited TSCC growth. The suppression of malignant phenotype was also accompanied by decreased photon signals, rare necrosis foci, smaller nucleuses, weakly stained nucleuses, atypia reversal and tumor angiogenesis reduction. Additionally, miR-21 expression was markedly decreased in TSCC xenografts and the apoptotic index was increased. Intratumor injection of AS-miR-21 into TSCC xenografts could reduce expression of miR-21, promote apoptosis of TSCC cells and inhibit TSCC proliferation.     

Radiotherapy suppressed tumor-specific recruitment of regulator T cells via up-regulating microR-545 in Lewis lung carcinoma cells

Objective: Radiotherapy is an important treatment for cancer. The main irradiated action is thought to be the irreversible damage to tumor cell DNA, but recent studies showed that high dose radiotherapy related to the tumor immune response. This study was designed to determine the relationship between Lewis lung tumor radiosensitivity and CD4+CD25+ regulatory T cells (Tregs) infiltration and elucidate the underlying mechanisms in vitro. Methods: With tumor transplantation method to establish mice Lewis lung tumor mice model, to observe the inhibition rate of radiotherapy to tumor growth. Proliferation profiles of CD4+CD25+ Tregs and CD4+ T cells were assessed by flow cytometry. MiR-545 and CCL-22 mRNA were determined by Quantitative Real-Time PCR. CCL-22 protein was determined by western blot assay. Results: Radiotherapy caused a time-dependent inhibition of tumor growth as well as a decrease in the percentage of tumor-infiltrating CD4+CD25+ Tregs of CD4+ T cells compared with no treatment group. And the miR-545 was significantly upregulated and CCL-22 was significantly down-regulated in irradiated tumor and Lewis lung cancer cells. In Lewis lung cancer cell transfection experiments, mimic or inhibitor for miR-545 negatively regulated CCL-22 expression when cells treated or treated without irradiation. Silenced miR-545 promotes CD4+CD25+ Treg proliferation. Additionally, silenced miR-545 reversed radiosensitivity of Lewis lung cancer. Conclusion: Radiotherapy suppressed specific recruitment of regulator CD4+CD25+ Treg cells in Lewis lung carcinoma via up-regulating microR-545.     

Expression and function of microRNA-188-5p in activated rheumatoid arthritis synovial fibroblasts

Activated synovial fibroblasts in rheumatoid arthritis (RASF) play a critical role in the pathology of rheumatoid arthritis (RA). Recent studies suggested that deregulation of microRNAs (miRs) affects the development and progression of RA. Therefore, we aimed to identify de-regulated miRs in RASF and to identify target genes that may contribute to the aggressive phenotype of RASF. Quantitative real-time PCR revealed a marked downregulation of miR-188-5p in synovial tissue samples of RA patients as well as in RASF. Exposure to the cytokine interleukine-1β lead to a further downregulation of miR-188-5p expression levels compared to control cells. Re-expression of miR-188-5p in RASF by transient transfection significantly inhibited cell migration. However, miR-188-5p re-expression had no effects on glycosaminoglycan degradation or expression of repellent factors, which have been previously shown to affect the invasive behavior of RASF. In search for target genes of miR-188-5p in RASF we performed gene expression profiling in RASF and found a strong regulatory effect of miR-188-5p on the hyaluronan binding protein KIAA1199 as well as collagens COL1A1 and COL12A1, which was confirmed by qRT-PCR. In silico analysis revealed that KIAA1199 carries a 3’UTR binding site for miR-188-5p. COL1A1 and COL12A1 showed no binding site in the mRNA region, suggesting an indirect regulation of these two genes by miR-188-5p. In summary, our study showed that miR-188-5p is down-regulated in RA in vitro and in vivo, most likely triggered by an inflammatory environment. MiR-188-5p expression is correlated to the activation state of RASF and inhibits migration of these cells. Furthermore, miR-188-5p is directly and indirectly regulating the expression of genes, which may play a role in extracellular matrix formation and destruction in RA. Herewith, this study identified potential novel therapeutic targets to inhibit the development and progression of RA.     

Expression and function of microRNA-188-5p in activated rheumatoid arthritis synovial fibroblasts

Activated synovial fibroblasts in rheumatoid arthritis (RASF) play a critical role in the pathology of rheumatoid arthritis (RA). Recent studies suggested that deregulation of microRNAs (miRs) affects the development and progression of RA. Therefore, we aimed to identify de-regulated miRs in RASF and to identify target genes that may contribute to the aggressive phenotype of RASF. Quantitative real-time PCR revealed a marked downregulation of miR-188-5p in synovial tissue samples of RA patients as well as in RASF. Exposure to the cytokine interleukine-1β lead to a further downregulation of miR-188-5p expression levels compared to control cells. Re-expression of miR-188-5p in RASF by transient transfection significantly inhibited cell migration. However, miR-188-5p re-expression had no effects on glycosaminoglycan degradation or expression of repellent factors, which have been previously shown to affect the invasive behavior of RASF. In search for target genes of miR-188-5p in RASF we performed gene expression profiling in RASF and found a strong regulatory effect of miR-188-5p on the hyaluronan binding protein KIAA1199 as well as collagens COL1A1 and COL12A1, which was confirmed by qRT-PCR. In silico analysis revealed that KIAA1199 carries a 3’UTR binding site for miR-188-5p. COL1A1and COL12A1 showed no binding site in the mRNA region, suggesting an indirect regulation of these two genes by miR-188-5p. In summary, our study showed that miR-188-5p is down-regulated in RA in vitro and in vivo, most likely triggered by an inflammatory environment. MiR-188-5p expression is correlated to the activation state of RASF and inhibits migration of these cells. Furthermore, miR-188-5p is directly and indirectly regulating the expression of genes, which may play a role in extracellular matrix formation and destruction in RA. Herewith, this study identified potential novel therapeutic targets to inhibit the development and progression of RA.     

MiR-191 inhibits TNF-α induced apoptosis of ovarian endometriosis and endometrioid carcinoma cells by targeting DAPK1

Emerging evidence showed that miRNA dysregulation is involved in the development of endometriosis and may contribute to pathological process of endometriosis associated ovarian cancer (EAOC). miR-191 is one of the most differentially expressed miRNAs in pairwise comparisons among healthy controls, endometriosis, and EAOC patients. However, its regulative network in endometriosis and EAOC are still not clear. This study explored the role of miR-191 in TNF-α induced cell death in ovarian endometriosis and endometrioid carcinoma cells. Based on tissues samples collected from healthy controls, endometriosis, and EAOC patients, this study verified significantly higher expression of miR-191 in endometriosis and endometrioid cancer. Interestingly, we also observed inverse expression trend between miR-191 and DAPK1, a positive mediator of programmed cell death. By conducting luciferase assay, we confirmed miR-191 can directly target DAPK1 and regulate its expression. Functionally, we also found DAPK1 can promote TNF-α induced cell death. DAPK1 knockdown in endometriosis CRL-7566 cells can weaken its response to TNF-α induced cell death, while its overexpression in endometrioid cancer cells CRL-11731 enhanced the response. These functions of DAPK1 can be directly modulated by miR-191. Therefore, the miR-191-DAPK1 axis may play an important role modulating the response of ovarian endometriosis and endometrioid carcinoma cells to death-inducers and might contribute malignant transformation of endometriosis.     

Augmented miR-10b expression associated with depressed expression of its target gene KLF4 involved in gastric carcinoma

Previous studies have revealed several targets of miR-10b, such as syndecan-1, HOXD10, TBX5, and E-cadherin. In this study, we aimed to assess whether Krüppel-like factor 4 (KLF4) is a target gene of miR-10b in gastric cancer (GC). Targeting of KLF4 by miR-10b was confirmed by dual-luciferase reporter assays. The expression levels of miR-10b and KLF4 mRNA in 5 different gastric cancer cell lines and 65 pairs of gastric cancer tissues were detected by Real-time PCR. In addition, KLF4 protein in gastric cancer cell lines and 30 GC tissues was measured by western blotting and immunochemistry, respectively. KLF4 is a direct target gene of miR-10b in GC, and its expression is reduced by miR-10b at both mRNA and protein levels. In addition, the expression level of miR-10b was tendentiously upregulated in GC tissues while the expression levels of KLF4 mRNA and protein were decreased in gastric cancer tissues compared with normal adjacent tissue. There was a dramatically inverse correlation between the expression levels of miR-10b and KLF4 mRNA in GC (r = -0.339, P = 0.006). These findings indicate that miR-10b was upregulated in GC and may have a key role in GC pathogenesis and development through the downregulation of its target gene KLF4.