c‐Src promotes tumor progression through downregulation of microRNA‐129‐1‐3p

MicroRNAs (miRNAs) fine‐tune cellular signaling by regulating expression of signaling proteins, and aberrant expression of miRNAs is observed in many cancers. The tyrosine kinase c‐Src is upregulated in various human cancers, but the molecular mechanisms underlying c‐Src‐mediated tumor progression remain unclear. In previous investigations of miRNA‐mediated control of c‐Src‐related oncogenic pathways, we identified miRNAs that were downregulated in association with c‐Src transformation and uncovered the signaling networks by predicting their target genes, which might act cooperatively to control tumor progression. Here, to further elucidate the process of cell transformation driven by c‐Src, we analyzed the expression profiles of miRNAs in a doxycycline‐inducible Src expression system. We found that miRNA (miR)‐129‐1‐3p was downregulated in the early phase of c‐Src‐induced cell transformation, and that reexpression of miR‐129‐1‐3p disrupted c‐Src‐induced cell transformation. In addition, miR‐129‐1‐3p downregulation was tightly associated with tumor progression in human colon cancer cells/tissues. Expression of miR‐129‐1‐3p in human colon cancer cells caused morphological changes and suppressed tumor growth, cell adhesion, and invasion. We also identified c‐Src and its critical substrate Fer, and c‐Yes, a member of the Src family of kinases, as novel targets of miR‐129‐1‐3p. Furthermore, we found that miR‐129‐1‐3p‐mediated regulation of c‐Src/Fer and c‐Yes is important for controlling cell adhesion and invasion. Downregulation of miR‐129‐1‐3p by early activation of c‐Src increases expression of these target genes and synergistically promotes c‐Src‐related oncogenic signaling. Thus, c‐Src‐miR‐129‐1‐3p circuits serve as critical triggers for tumor progression in many human cancers that harbor upregulation of c‐Src.     

丹蛭降糖胶囊通过mTOR/S6K1信号通路对糖尿病肾病大鼠的干预作用研究

目的研究丹蛭降糖胶囊对糖尿病肾病大鼠的肾脏病理改变和足细胞自噬水平的影响,初步探讨其相应的作用机制。方法选取GK大鼠40只,采用醋酸脱氧皮质酮-盐皮下注射联合高脂饲料喂养诱导糖尿病肾病模型。造模成功后随机分为模型组、丹蛭降糖胶囊低剂量组[0.54 g/(kg·d)]、高剂量组[1.08 g/(kg·d)]、缬沙坦组[10 mg/(kg·d)],每组10只。另选取10只同周龄正常Wistar大鼠作为正常组。模型组和正常组给予等容积生理盐水。连续灌胃10周后检测空腹血糖(FBG)、血肌酐(SCr)、尿素氮(BUN)和尿微量蛋白(U-mAlb)。Western Blot检测肾小球p-mTOR、p-S6K1、Beclin-1、LC3和Nephrin蛋白的表达,HE染色和PAS染色后于光镜下观察肾脏病理变化,电镜下观察各组亚细胞形态结构变化。结果与正常组比较,模型组FBG、SCr、BUN、U-mAlb水平升高(P<0.01);与模型组比较,丹蛭降糖胶囊低、高剂量组和缬沙坦组U-mAlb水平降低(P<0.01)。模型组可见肾小球基底膜增厚,系膜基质沉积,足细胞损伤,各用药组均有不同程度改善,丹蛭降糖胶囊高剂量组足细胞内有较多自噬体形成。与正常组比较,模型组p-mTOR、p-S6K1的表达增高,Nephrin、Beclin-1和LC3的表达水平降低(P<0.01);与模型组比较,各用药组p-mTOR、p-S6K1的表达下降,Nephrin、Beclin-1和LC3的表达增高(P<0.01)。丹蛭降糖胶囊高剂量组和缬沙坦组Beclin1、LC3Ⅱ/LC3Ⅰ水平较丹蛭降糖胶囊低剂量组升高(P<0.05)。结论丹蛭降糖胶囊具有减轻糖尿病肾病大鼠U-mAIb、足细胞损伤及相关肾脏病理改变的作用,其机制可能与抑制mTOR/S6K1信号通路进而提高足细胞的自噬活性有关。     

A Murine Model of Chronic Lymphocytic Leukemia Based on B Cell-Restricted Expression of Sf3b1 Mutation and Atm Deletion

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Suppression of KIF3A inhibits triple negative breast cancer growth and metastasis by repressing Rb‐E2F signaling and epithelial‐mesenchymal transition

Triple negative breast cancer (TNBC) displays higher heterogeneity, stronger invasiveness, higher risk of metastasis and poorer prognosis compared with major breast cancer subtypes. KIF3A, a member of the kinesin family of motor proteins, serves as a microtubule‐directed motor subunit and has been found to regulate early development, ciliogenesis and tumorigenesis. To explore the expression, regulation and mechanism of KIF3A in TNBC, 3 TNBC cell lines, 98 cases of primary TNBC and paired adjacent tissues were examined. Immunohistochemistry, real‐time PCR, western blot, flow cytometry, short hairpin RNA (shRNA) interference, 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT), colony formation techniques, transwell assays, scratch tests, and xenograft mice models were used. We found that KIF3A was overexpressed in TNBC and such high KIF3A expression was also associated with tumor recurrence and lymph node metastasis. Silencing of KIF3A suppressed TNBC cell proliferation by repressing the Rb‐E2F signaling pathway and inhibited migration and invasion by repressing epithelial‐mesenchymal transition. The tumor size was smaller and the number of lung metastatic nodules was lower in KIF3A depletion MDA‐MB‐231 cell xenograft mice than in the negative control group. In addition, KIF3A overexpression correlated with chemoresistance. These results suggested that high expression of KIF3A in TNBC was associated with the tumor progression and metastasis.     

Hydroxychloroquine is a novel therapeutic approach for rosacea

Rosacea is a chronic inflammatory disease in face. Hydroxychloroquine (HCQ), an anti-malaria drug, was reported to have anti-inflammation activities. However, the role of HCQ on rosacea remains unclear. In this study, we revealed the potential molecular mechanism by which HCQ improved rosacea in rosacea-like mice and mast cells (MCs). Moreover, the effects of HCQ treatment for rosacea patients were investigated. In this study, we found HCQ ameliorated the rosacea-like phenotype and MCs infiltration. The elevated pro-inflammatory factors and mast cell protease were significantly inhibited by HCQ treatment in rosacea-like mice. In vitro, HCQ suppresses LL37-induced MCs activation in vitro, including the release of inflammatory factors, chemotaxis, degranulation and calcium influx. Moreover, HCQ attenuated LL37-mediated MCs activation partly via inhibiting KCa3.1-mediated calcium signaling. Thus, these evidences suggest HCQ ameliorated rosacea-like dermatitis may be by regulating immune response of MCs. Finally, the 8-week HCQ treatment exerted satisfactory therapeutic effects on erythema and inflammatory lesions of rosacea patients, indicating that it is a promising drug for rosacea in clinical treatment.     

A hotspot mutation in transcription factor IKZF3 drives B cell neoplasia via transcriptional dysregulation

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正畸力调控牙周膜干细胞成骨分化的动物实验研究

目的 研究不同正畸力值对牙周膜干细胞(periodontal ligament stem cells,PDLSCs)分化的作用及机制.方法 分别用50 g、150 g力值建立大鼠牙齿移动模型,加力7d后分离培养PDLSCs,检测其生物学功能和分子信号通路.结果 相比对照组,加力7d后,50 g力值组大鼠第一磨牙近中移动,150 g力值组移动距离大于50 g力值组.分离培养不同组PDLSCs,50 g力值组PDLSCs成骨和成脂分化能力均高于对照组;150 g力值组PDLSCs成骨分化能力小于对照组,而成脂分化能力大于对照组.机制研究显示50 g力值组PDLSCs的active-β-catenin表达水平高于对照组,而150 g力值组PDLSCs的active-β-catenin表达水平低于对照组.结论 不同正畸力值对PDLSCs作用不同,50 g力值促进PDLSCs成骨和成脂分化,而150 g力值抑制其成骨分化.