Monoclonal gammopathy of undetermined significance in systemic transthyretin amyloidosis (ATTR)

Objective: To identify the prevalence of monoclonal gammopathy of undetermined significance (MGUS) in patients with transthyretin (ATTR) amyloidosis.

Patients and methods: We performed a retrospective analysis of patients with biopsy-proven ATTRwt (wild-type transthyretin amyloid protein) and genopositive ATTR V122I (valine-to-isoleucine substitution at position 122 of the TTR gene) amyloidosis evaluated at the Amyloidosis Center at Boston University and Boston Medical Center between 1 January 2003 and 31 December 2016.

Results: There were a total of 226 patients with ATTRwt and ATTR V122I amyloidosis evaluated during the specified time frame with 155 and 71 patients in each cohort, respectively. Those with complete medical records, 140 patients with ATTRwt and 57 V1221 ATTRm subjects, were included in the analyses. Fifty-five patients (39%) in the ATTRwt cohort and 28 patients (49%) in the ATTR V122I cohort had an MGUS, as indicated by an abnormality in the serum-free light-chain ratio and/or serum immunofixation electrophoresis.

Conclusion: These data confirm the high prevalence of coexistent MGUS with ATTR amyloidosis in this patient population, with an MGUS rate that is higher than the general population. These findings also highlight the importance of a thorough diagnostic evaluation in patients with amyloidosis to determine the precursor protein, as the clinical course and treatment of AL (light-chain amyloid protein) and ATTR amyloidosis are distinct.     

miRNA-449a在肺癌组织中的表达及其检测意义

目的探讨miRNA-449a在肺癌组织中的表达及其临床应用价值。方法收集右江族医学院附属医院2011年1月1日~2013年6月30日收治的58例肺癌患者为研究对象,采用反转录荧光定量聚合酶链式反应(RT-PCR)检测miRNA-449a在肺癌组织和癌旁正常组织中的表达量,分析miRNA-449a与临床病理特征的关系,并采用荧光电子显微镜观察miRNA-449a模拟物对体外培养肺癌细胞株95D细胞凋亡的影响。结果鳞癌组和腺癌组miRNA-449a平均表达量均明显低于癌旁正常对照组(LSD-t=6.712,P=0.000;LSD-t=4.572,P=0.000),其相对表达量与瘤体大小(u=78.412,P=0.012)有关,与患者年龄(u=920.000,P=0.615)、性别(u=800.000,P=0.215)、病理类型(χ2=4.221,P=0.155)和临床分期(u=754.000,P=0.009)无关。与阴性对照组比较,miRNA-449a模拟物可明显促进肺癌细胞的凋亡,且呈剂量依赖性。结论 miRNA-449a在肺癌组织中呈低表达,可诱导肺癌细胞凋亡,发挥抑癌基因的作用,可能成为肺癌早期诊断与治疗的新分子靶标。     

Low Prevalence of Clinically Apparent Cardiac Amyloidosis Among Carriers of Transthyretin V122I Variant in a Large Electronic Medical Record

BackgroundTransthyretin (TTR) gene mutations are the most common cause of hereditary amyloidosis. Valine replaced by isoleucine in position 122 (V122I) variant is common, particularly in the black population. Carriers of V122I have increased risk for developing cardiac amyloidosis. Despite a relatively high prevalence, the penetrance of V122I is not firmly established. This study sought to determine the prevalence of clinically apparent cardiac amyloidosis among carriers of the TTR V122I variant.MethodsBioVU, a Vanderbilt University resource linking DNA samples and pre-existing genetic data to de-identified electronic medical records was used to identify TTR V122I mutation carriers. Automated billing code queries (International Classification of Diseases, 9th revision codes), problem list searches, and manual chart reviews were used to identify subjects with clinically diagnosed cardiac amyloidosis.ResultsAmong 28,429 subjects with available genotype data, 129 were V122I carriers. Carriers had a median age of 42 years (interquartile range 16-64). Noncarriers had a median age of 62 years, (interquartile range 41-77). The carrier rate was 3.7% in blacks and 0.02% in whites. Overall, the prevalence of clinically apparent cardiac amyloidosis was 0.8% in carriers and 0.04% in noncarriers (P = .05). Above age 60, the prevalence of cardiac amyloidosis was 2.6% in carriers and 0.06% in noncarriers (P = .03).ConclusionCarriers of the TTR V122I variant are at a higher risk for development of cardiac amyloidosis, particularly at age>60 years. However, clinically apparent cardiac amyloidosis in this population was uncommon. These results support that the penetrance of TTR V122I is age dependent and suggest it may be significantly lower than previously reported.     

miRNA-126-3p 与先天性心脏病肺动脉高压发病机制相关性的临床研究

目的：探讨 miRNA-126-3p 与肺动脉高压（以下简称肺高压）发病机制的相关性。方法选取25例先天性心脏病患者,其中,肺高压患者11例,对照组14例,采用 qRT-PCR 法检测其肺组织 miRNA-126-3p 的表达,并采用 starBase 进行靶基因预测,并从 mRNA 水平和蛋白水平进行验证。结果肺高压患者与对照组在年龄、性别、生化指标检查等方面比较差异无统计学意义（P＞0．05）;肺高压患者 miRNA-126-3p 表达水平与对照组比较差异有统计学意义（P＜0．01）;生物信息学预测发现 miRNA-126-3p 的生物学功能主要与结合蛋白、信号转导、细胞分化、调控细胞形态、调控 MAPK 和胰岛素受体信号通路等有关,其靶基因主要有 VEGFA 、SPRED1、PIK3R2等;肺高压组的 VEGFA 表达在 mRNA 水平和蛋白水平与对照组比较差异有统计学意义（P＜0．01）;miRNA-126-3p 与 VEGFA 呈现正相关（P＜0．01）。结论 miRNA-126-3p 可能通过调控 VEGFA 参与先天性心脏病相关性肺动脉高压发病。     

Lipotoxic hepatocyte-derived exosomal miR-1297 promotes hepatic stellate cell activation through the PTEN signaling pathway in metabolic-associated fatty liver disease

BACKGROUNDExosomes play an important role in metabolic-associated fatty liver disease (MAFLD), but the mechanism by which exosomes participate in MAFLD still remain unclear.AIMTo figure out the function of lipotoxic exosomal miR-1297 in MAFLD.METHODSMicroRNA sequencing was used to detect differentially expressed miRNAs (DE-miR) in lipotoxic exosomes derived from primary hepatocytes. Bioinformatic tools were applied to analyze the target genes and pathways regulated by the DE-miRs. Quantitative real-time PCR (qPCR) was conducted for the verification of DE-miRs. qPCR, western blot, immunofluorescence staining and ethynyl-20-deoxyuridine assay were used to evaluate the function of lipotoxic exosomal miR-1297 on hepatic stellate cells (LX2 cells). A luciferase reporter experiment was performed to confirm the relationship of miR-1297 and its target gene PTEN. RESULTSMicroRNA sequencing revealed that there were 61 exosomal DE-miRs (P < 0.05) with a fold-change > 2 from palmitic acid treated primary hepatocytes compared with the vehicle control group. miR-1297 was the most highly upregulated according to the microRNA sequencing. Bioinformatic tools showed a variety of target genes and pathways regulated by these DE-miRs were related to liver fibrosis. miR-1297 was overexpressed in exosomes derived from lipotoxic hepatocytes by qPCR. Fibrosis promoting genes (α-SMA, PCNA) were altered in LX2 cells after miR-1297 overexpression or miR-1297-rich lipotoxic exosome incubation via qPCR and western blot analysis. Immunofluorescence staining and ethynyl-20-deoxyuridine staining demonstrated that the activation and proliferation of LX2 cells were also promoted after the above treatment. PTEN was found to be the target gene of miR-1297 and knocking down PTEN contributed to the activation and proliferation of LX2 cells via modulating the PI3K/AKT signaling pathway.CONCLUSIONmiR-1297 was overexpressed in exosomes derived from lipotoxic hepatocytes. The lipotoxic hepatocyte-derived exosomal miR-1297 could promote the activation and proliferation of hepatic stellate cells through the PTEN/PI3K/AKT signaling pathway, accelerating the progression of MAFLD.     

miR-183 promotes radioresistance of lung adenocarcinoma H1299 cells via epithelial-mesenchymal transition

Lung adenocarcinomas are usually sensitive to radiation therapy, but some develop resistance. Radiation resistance can lead to poor patient prognosis. Studies have shown that lung adenocarcinoma cells (H1299 cells) can develop radioresistance through epithelial-mesenchymal transition (EMT), and this process is regulated by miRNAs. However, it is unclear which miRNAs are involved in the process of EMT. In our present study, we found that miR-183 expression was increased in a radioresistant lung adenocarcinoma cell line (H1299R cells). We then explored the regulatory mechanism of miR-183 and found that it may be involved in the regulation of zinc finger E-box-binding homeobox 1 (ZEB1) expression and mediate EMT in lung adenocarcinoma cells. qPCR results showed that miR-183, ZEB1, and vimentin were highly expressed in H1299R cells, whereas no difference was observed in E-cadherin expression. Western blot results showed that ZEB1 and vimentin were highly expressed in H1299R cells, while E-cadherin expression was decreased. When miR-183 expression was inhibited in H1299R cells, radiation resistance, proliferation, and cell migration were decreased. The expression of ZEB1 and vimentin in H1299R cells was decreased, while the expression of E-cadherin was increased. Moreover, miR-183 overexpression in H1299 cells enhanced radiation resistance, proliferative capacity, and cell migration ability. The expression of ZEB1 and vimentin in H1299 cells was increased, while that of E-cadherin was decreased. In conclusion, miR-183 may promote EMT and radioresistance in H1299 cells, and targeting the miR-183-ZEB1 signaling pathway may be a promising approach for lung cancer treatment.     

miR－21调控TGF－β1诱导的大鼠BMSCs向肌成纤维细胞分化的机制研究

目的：在细胞水平探索miR－21在调控TGF－β1诱导的大鼠骨髓间充质干细胞向肌成纤维细胞分化中的作用。方法：全髓培养法培养原代大鼠骨髓间充质干细胞,培养至第三代时用TGF－β1分组诱导培养,检测TGF－β1对大鼠BMSCs促纤维化的作用及该过程中不同浓度梯度TGF－β1诱导以及不同时间段miR－21的表达变化;通过转染miR－21 mimics（高表达）不同时间点检测其对α－SMA表达的影响。结果：TGF－β1能促进大鼠骨髓间充质干细胞向成纤维,肌成纤维细胞分化;大鼠骨髓间充质干细胞向成纤维,肌成纤维细胞分化后miR－21表达上调;上调miR－21能促进大鼠BMSCs的纤维化作用。结论：miR－21 mimics能够促进大鼠BMSCs的纤维化作用。     

Decreased expression of microRNA-130a correlates with TNF-α in the development of osteoarthritis

Objective: Increased expression of tumor necrosis factor a (TNF-α) has emerged as an important inflammatory factor in osteoarthritis (OA) and other joint diseases. The study was performed to investigate whether the expression of TNF-α in human chondrocytes was regulated by miRNAs. Methods: MiRNA-130a and TNF-α expression in cartilage specimens was examined in patients with knee osteoarthritis, chondrocytes and osteoarthritis rat model. Chondrocytes were transfected with siRNAs as a gene silencing methods. Expression of genes and proteins were analyzed by real-time PCR and western blotting respectively. Results: Increased TNF-α and decreased miRNA-130a were observed in tissues from osteoarthritis patients. Moreover, we found a highly negitive correlation between miRNA-130a and TNF-α. Next, miRNA-130a loss-of-function increased the expression of TNF-α and promoted inflammation in chondrocytes. It was reasonable that miRNA-130a regulated a distinct underlying molecular and pathogenic mechanism of OA by forming a negative feedback loop with TNF-α. Furthermore, there were the abnormalities of bone metabolism in OA rat, which showed the miRNA-130a and TNF-α dysfunction that was one of important factors for the occurrence and development of OA. Conclusions: Our results indicated that miR-130a played an important role in regulating the expression of TNF-α in human chondrocytes and identified miR-130a as a novel therapeutic target in OA.     

基于微流控平台的胶质母细胞瘤干细胞中miRNA-874表达的研究

目的通过微流控检测平台,研究miRNA-874（miR-874）表达在胶质母细胞瘤干细胞（GSCs）生长中的作用及意义。 方法应用高通量、多样本、低成本的微流控技术,对GSCs和神经干细胞（NSCs）进行miR-874转染,并通过荧光定量PCR检测细胞内miR-874和mRNA表达等一系列细胞分子生物实验,研究miRNA-874对GSCs生长和凋亡的作用。 结果miR-874在GSCs中的表达显著降低,约为NSCs中表达量的2%~40%（P<0.05）。利用树状分子将miR-874转染入GSCs中后,GSCs的细胞数量显著下降,凋亡细胞的数量显著上升,提示miR-874对GSCs具有杀伤作用。 结论miR-874在GSCs中表达显著降低,在GSCs中过表达miR-874会导致显著的细胞生长抑制和死亡,有助于开发基于miRNA的新型脑癌药物和疗法。