miR-149与肿瘤关系的研究进展

miRNAs是一类长度约为20~25个核苷酸，参与基因调控表达的内源性非编码RNA。miR-149作为miRNAs的重要成员，在多种肿瘤中表达异常，其表达水平与肿瘤细胞增殖、转移、凋亡、耐药、患者的早期诊断及预后密切相关。因此，miR-149有望成为新一类抗肿瘤治疗的靶点。     

miR-513a-5p慢病毒载体的构建及其对人骨肉瘤细胞放疗敏感性的影响

目的:构建miR-513a-5p慢病毒过表达载体，转染人骨肉瘤细胞株，观察miR-513a-5p对人骨肉瘤细胞放疗敏感性的影响。方法:PCR法扩增人miR-513a-5p基因，克隆入pLentis-CMV-GFP-MCS-PGK-PURO载体获得重组质粒pLentis-miR513a，双酶切鉴定并测序后将正确的重组质粒和对照质粒转染293FT细胞制备慢病毒，分别转染骨肉瘤HOS和U2OS细胞，qRT-PCR法及荧光显微镜鉴定转染结果。克隆形成实验、MTT法检测miR-513a-5p高表达HOS和U2OS细胞在X射线照射下细胞存活情况。结果:双酶切及测序结果确定成功构建miR-513a-5p慢病毒载体pLentis-miR513a。qRT-PCR结果提示，转染骨肉瘤细胞株后miR-513a-5p表达显著升高。克隆形成实验结果显示miR-513a-5p高表达后骨肉瘤细胞在X射线照射下细胞增殖减慢。MTT结果提示miR-513a-5p高表达骨肉瘤细胞经X射线照射后细胞存活减少。结论:成功构建了miR-513a-5p慢病毒载体，建立了高效稳定表达miR-513a-5p的骨肉瘤细胞株，高表达miR-513a-5p能显著增加X射线照射后骨肉瘤细胞的放疗敏感性。     

miR-503靶向TLR4对前列腺癌多西他赛耐药的影响

背景与目的：在前列腺癌标准化疗方案中，多西他赛（docetaxel，DTX）引起的化疗耐药是引起患者死亡的重要原因之一，然而DTX引起的化疗耐药相关机制尚未知。探讨前列腺癌DTX耐药的作用机制。方法：收集2016年6月—2019年6月在武汉市第三医院进行化疗的40例患者，包括20例DTX耐药和20例DTX敏感患者。人前列腺癌细胞系PC-3在一系列逐渐增加的DTX浓度梯度处理下形成耐药株PC-3/DTX。采用实时荧光定量聚合酶链反应（real-time fluorescence quantitative polymerase chain reaction，RTFQ-PCR）检测miR-503和TLR4 mRNA的表达，采用蛋白质印迹法（Western blot）检测TLR4蛋白的水平，采用双荧光素酶报告基因检测miR-503和TLR4的相互作用，采用四甲基偶氮唑蓝（methyl thiazolyl tetrazolium，MTT）法检测细胞活力，采用流式细胞术检测细胞凋亡。结果：前列腺癌耐药患者组织和耐药细胞系中miR-503的表达较敏感组显著降低（P=0.013），而TLR4显著增加（P=0.005 6）。过表达miR-503显著抑制耐药细胞的增殖，促进凋亡，同时抑制耐药相关蛋白MDR-1的表达，而过表达TLR4则促进细胞的增殖，抑制凋亡，促进耐药相关蛋白MDR-1的表达。结论：miR-503通过靶向调控TLR4的表达影响前列腺癌的DTX耐药。     

miR-26b通过调节Notch1信号通路参与原发性肝细胞肝癌侵袭的机制研究

目的:探讨miR-26b参与原发性肝细胞肝癌（HCC）侵袭的机制。方法:在细胞培养液中培养人肝细胞系HL-7702和HCC细胞各系Hepb-3、HuH-7、MHCC97-L、MHCC97-H。实时荧光定量PCR法（qRT-PCR）检测miR-26b的表达水平；用miR-26b mimics、miR-26b inhibitors和Notch1-siRNA分别转染HCC细胞；MTT实验检测转染后HCC细胞的活力；采用Western blot检测Notch1受体蛋白表达水平的变化；Transwell小室测定不同处理后的HCC细胞的侵袭能力。结果:人正常肝细胞系HL-7702和HCC细胞系Hepb-3、HuH-7、MHCC97-L、MHCC97-H中的miR-26b相对表达含量随其侵袭和迁移能力的升高而依次下降；抑制miR-26b的表达，Notch1受体蛋白表达明显增高，而此时HCC细胞的侵袭性显著增强；相反，上调miR-26b的表达，Notch1受体蛋白表达明显降低，而HCC细胞侵袭性显著下降；miR-26b可能通过调控Notch1信号通路调节HCC细胞侵袭性。结论:miR-26b通过负调控Notch1信号通路抑制HCC细胞侵袭能力，为HCC侵袭的机制奠定了理论基础，miR-26b可能成为HCC治疗的新靶点。     

miR-30c Impedes Glioblastoma Cell Proliferation and Migration by Targeting SOX9

miR-30c has been acknowledged as a tumor suppressor in various human cancers, such as ovarian cancer, gastric cancer, and prostate cancer. However, the role of miR-30c in glioblastoma (GBM) needs to be investigated. In our study, we found that the expression of miR-30c was significantly downregulated in GBM tissues and cell lines. We found that overexpression of miR-30c inhibited cellular proliferation of GBM cells in vitro and in vivo. More GBM cells were arrested in the G₀ phase after miR-30c overexpression. Moreover, we showed that miR-30c overexpression suppressed the migration and invasion of GBM cells. Mechanistically, we found that SOX9 was a direct target of miR-30c in GBM cells. Overexpression of miR-30c inhibited the mRNA and protein levels of SOX9 in GBM cells. Moreover, there was a negative correlation between the expression of miR-30c and SOX9 in GBM tissues. Finally, we showed that restoration of SOX9 in GBM cells reversed the proliferation, migration, and invasion of GBM cells transfected with miR-30c mimic. Collectively, our results demonstrated that miR-30c suppressed the proliferation, migration, and invasion of GBM cells via targeting SOX9.     

HBV-ACLF患者血清miR-122和 HMGB1水平及其与病情、预后的关系

[摘要]　目的　探究HBV相关慢加急性肝衰竭（HBV-related acute-on-chronic liver failure, HBV-ACLF）患者血清中微小核糖核酸（microRNA, miR）-122和高迁移率族蛋白1（high-mobility group box-B1, HMGB1）水平及其与病情、预后的关系。方法　回顾性分析2016年1月—2018年1月我院收治的120例HBV-ACLF患者的一般及临床资料。根据临床结局，将患者分为存活组（53例）和死亡组（67例）。比较2组患者的一般资料、实验室检查指标及血清miR-122、HMGB1水平。多因素Logistic回归分析影响患者预后的因素。Pearson检验分析miR-122、HMGB1水平分别与TBIL、PA、终末期肝病评分模型（the model of end-stage liver disease score, MELD）评分的相关性。ROC曲线分析miR-122和HMGB1水平对患者的死亡预测价值，获得最佳临界值。根据临界值将患者分为A组、B组和C组，用Kaplan-Meier法绘制生存曲线，比较3组患者在3年随访期间的生存率。结果　存活组和死亡组患者的年龄、身体质量指数、并发症、病情分期、MELD评分、ALB、球蛋白、TBIL、ALT、AST、LDH、PT、PTA、HBV DNA、miR-122、HMGB1相比，差异均具有统计学意义（P均＜0.05）。年龄、并发症、病情分期、MELD评分、TBIL、PT、PTA、miR-122、HMGB1均是影响患者预后的危险因素（P均＜0.05）。miR-122、HMGB1水平分别与TBIL、MELD评分呈显著正相关，与PTA呈显著负相关（P均＜0.05）。miR-122和HMGB1预测患者死亡的最佳临界值分别为31.42和14.56 μg/L。A组患者预后3年内生存率显著高于B组和C组（P均＜0.05）。结论　miR-122和HMGB1水平与HBV-ACLF患者的病情和死亡预后密切相关，可间接反映患者的病情严重程度，在HBV-ACLF的诊断及预后中具有重要价值。     

miR-451a suppresses the development of breast cancer via targeted inhibition of CCND2

Extensive research has indicated that miRNAs are crucial for the occurrence and progression of cancers. miR-451a, involved in breast cancer (BC), is one of the miRNAs. This study focused on the mechanism by which miR-451a regulates BC. The levels of miR-451a in BC tissues and cell lines were examined using quantitative real-time polymerase chain reaction (qRT-PCR). Kaplan‒Meier analysis showed that this was intimately related to the patient's overall survival rate. Functional experiments revealed the negative effects of miR-451a on the abilities of BC cells to multiply (tested by Cell Counting Kit-8), migrate (tested by wound healing assay), and invade (tested by Transwell assay) and its positive effects on apoptosis (tested by flow cytometry). Western blotting indicated that the expression of tumor-related proteins was affected by miR-451a. Moreover, in vivo experiments suggested that tumor growth was clearly restrained by an miR-451a agonist in a xenograft tumor model. Bioinformatic analysis indicated that miR-451a directly targeted Cyclin D2 (CCND2), as demonstrated by the luciferase reporter assay. An opposite change in the level of CCND2 and miR-451a in BC was indicated by qRT-PCR, western blotting, and immunohistochemistry. Subsequently, functional experiments and western blotting analysis confirmed that CCND2 accelerated BC progression, which was regulated by miR-451a. Cumulatively, research on miR-451a may be valuable for BC treatment.     

miR-147对胶质瘤U87细胞增殖、凋亡和侵袭的影响

目的:比较胶质瘤患者胶质瘤组织和瘤旁组织中miR-147表达水平的差异性，进一步分析miR-147与胶质瘤细胞生物学活性的相关性。方法:通过实时荧光定量PCR检测65例胶质瘤患者瘤组织和瘤旁组织中miR-147的表达水平；采用Lipofectamine 2000转染法转染胶质瘤细胞，分为miR-147 mimics组和NC组，检测两组转染效率；进一步通过CCK-8实验、流式细胞实验和Transwell实验比较两组细胞生物活性。结果:胶质瘤组织中miR-147表达水平显著低于瘤旁组织；与NC组比较，miR-147 mimics组细胞不论是增殖能力还是侵袭能力都明显降低，但是，miR-147 mimics组的细胞凋亡率升高。结论:胶质瘤组织中存在miR-147低表达的现象。miR-147在胶质瘤细胞中表达升高能够抑制细胞的增殖能力、降低其侵袭能力，并促使更多的细胞发生晚期凋亡。miR-147可能在胶质瘤中扮演着抑癌基因的重要角色。     

MicroRNA‐375‐3p enhances chemosensitivity to 5‐fluorouracil by targeting thymidylate synthase in colorectal cancer

Resistance to chemotherapy is a major challenge for the treatment of patients with colorectal cancer (CRC). Previous studies have found that microRNAs (miRNAs) play key roles in drug resistance; however, the role of miRNA‐373‐3p (miR‐375‐3p) in CRC remains unclear. The current study aimed to explore the potential function of miR‐375‐3p in 5‐fluorouracil (5‐FU) resistance. MicroRNA‐375‐3p was found to be widely downregulated in human CRC cell lines and tissues and to promote the sensitivity of CRC cells to 5‐FU by inducing colon cancer cell apoptosis and cycle arrest and by inhibiting cell growth, migration, and invasion in vitro. Thymidylate synthase (TYMS) was found to be a direct target of miR‐375‐3p, and TYMS knockdown exerted similar effects as miR‐375‐3p overexpression on the CRC cellular response to 5‐FU. Lipid‐coated calcium carbonate nanoparticles (NPs) were designed to cotransport 5‐FU and miR‐375‐3p into cells efficiently and rapidly and to release the drugs in a weakly acidic tumor microenvironment. The therapeutic effect of combined miR‐375 + 5‐FU/NPs was significantly higher than that of the individual treatments in mouse s.c. xenografts derived from HCT116 cells. Our results suggest that restoring miR‐375‐3p levels could be a future novel therapeutic strategy to enhance chemosensitivity to 5‐FU.     

miR-122 Inhibits Hepatocarcinoma Cell Progression by Targeting LMNB2

In the present study, we investigated the role of miR-122 in hepatocarcinoma progression and explored the mechanism. In hepatocarcinoma tissues and cells, we used qRT-PCR to validate the miR-122 expression level. Next, we used colony formation by crystal violet staining assay to compare cell proliferation ability, and we used scratch test or Transwell assay to compare cell migration or invasion ability. We then conducted bioinformatics or luciferase reporter gene assay to prove the regulation effect of miR-122 on lamin B2 (LMNB2), and the biological function of LMNB2 was analyzed. We used nude mouse tumorigenicity assay to test the inhibition effect of miR-122 ASO therapy against hepatocarcinoma. miR-122 was reduced in hepatocarcinoma tissues compared to the paracarcinoma tissues, which was relatively low or high in hepatocarcinoma cell line SMMC7721 or Hep3B, and overexpressed miR-122 inhibited proliferation, migration, and invasion in hepatocarcinoma cells. Additionally, some reports showed that LMNB2 was regulated by miR-122, which inhibited the expression of LMNB2. Moreover, LMNB2 functioned to promote cell proliferation, migration, and invasion. We could achieve the inhibition of hepatocarcinoma using miR-122 therapy through decreasing LMNB2 expression in vivo. Our data indicated that miR-122 could inhibit hepatocellular carcinoma cell progression by targeting LMNB2 and as a therapeutic target for hepatocarcinoma treatment.