MicroRNA-539靶向调控E2F转录因子3抑制肝癌的发生与发展

目的 探讨肝癌组织中microRNA-539（miR-539）表达水平及其抑制肝癌细胞增殖的作用机制。方法 收集90例肝癌患者术后肝癌组织及癌旁组织标本,用实时定量聚合酶链反应（Real-time PCR）检测组织中miR-539表达量。在PCL/PRF5、Huh7和QGY-7701肝癌细胞中转染miR-539 模拟物（mimics）,用Real-time PCR检测miR-539表达量。用MTT法检测miR-539对肝癌细胞增殖的影响;用流式细胞仪检测miR-539对肝癌细胞凋亡的影响;用免疫印迹法检测miR-539对肝癌细胞中E2F转录因子3（E2F3）蛋白表达的影响。结果 肝癌组织中miR-539表达量显著低于癌旁组织（P<0.05）;miR-539表达量与肝癌患者性别、年龄及肝癌组织分化程度无关（P>0.05）;与肿瘤直径和淋巴结转移相关（P<0.05）。转染miR-539 mimics组肝癌细胞中miR-539表达量显著高于空白组和miR-539 NC组（P<0.05）。在QGY-7701细胞中,过表达miR-539能显著抑制细胞增殖（P<0.05）,降低E2F3蛋白的表达（P<0.05）,对细胞凋亡无明显作用（P>0.05）。结论 miR-539是肝癌发生中的抑癌因子,可能是通过靶向下调E2F3蛋白水平达到抑制癌细胞的增殖。     

c-Kit mutation reduce intestinal epithelial cell proliferation and migration,but not influence intestinal permeability stimulated by lipopolysaccharide

The proto-oncogene c-kit, as a marker of interstitial cells of Cajal (ICCs) in the gastrointestinal tract, plays an important role in the ICCs. Although limited evidences showed c-kit is present in the colonic epithelium but its roles remain unclear. In the present study, we aimed to investigate the expression, location and function of c-kit in the intestinal epithelium. Immunofluorescence, western blotting, and RT-PCR were performed to detect the expression and location of c-kit in the intestinal mucosa of WT mice. We investigated intestinal epithelial proliferation and migration in vivo by performing 5-Bromodeoxyuridine (BrdU) incorporation and Ki-67 staining in WT and Wads ^m/m mice. An Ussing chamber with fluorescein-isothiocyanate dextran 4000 was used to detect the transepithelial electric resistance (TER), short circuit current (ISC) and permeability across ex vivo colon segments under control and endotoxaemia conditions. We demonstrated that c-kit was located and expressed in the gut crypt compartment in WT mice, which was demonstrated in the c-kit mutant mice (Wads ^m/m). In addition, both the number of proliferating cells and the percentage of the distance migrated were lower in the Wads ^m/m mice than those in the WT mice. Moreover, the intestinal permeability, TER and tight junction were unaltered in the Wads ^m/m mice under endotoxic conditions compared with those in both the control condition and the WT mice. Altogether, these observations imply that the expression of c-kit in the colonic epithelium is involved in the proliferation and permeability of the colonic epithelium.     

釉质基质蛋白对乳牙牙髓干细胞体外增殖、分化能力的影响

目的：研究釉质基质蛋白（enamel matrix proteins,EMPs）对人脱落乳牙牙髓干细胞（stem cells from hu—man exfoliated dediduous teeth,SHED）体外增殖分化能力的影响。方法：利用酶消化法联合组织块法获得脱落乳牙牙髓干细胞,并进行形态学观察。三氯乙酸法制备EMPs,用不同浓度的EMPs对SHED进行诱导,利用四唑盐比色法（MTT）检测并分析诱导后的SHED增殖活性的变化,检测经诱导后的培养液中碱性磷酸酶（ALP）。RT—PCR检测牙本质涎磷蛋白（dentin sialophosphoprotein,DSPP）及牙本质基质蛋白1（dentin matrix protein1,DMP-1）的mRNA表达。结果：人脱落乳牙牙髓干细胞呈集落生长,并且在体外具有一定的自我增殖能力。EMPs对乳牙牙髓干细胞的增殖无明显影响,而能够显著提高ALP的活性,并呈现一定的剂量依赖性。经EMPs诱导后,细胞相对高表达DSPP、DMP-1mRNA。结论：EMPs对于SHED向成牙本质样分化具有积极作用。     

MTUS1／ATIP1对舌鳞癌细胞增殖及凋亡的影响

目的：探讨过表达MTUS1/ATIP1对舌鳞癌细胞增殖及凋亡的影响。方法检测人舌鳞癌系UM1、SCC鄄9、SCC鄄15、Tca8113细胞株中MTUS1的表达水平。应用含ATIP1片段的质粒转染舌鳞癌细胞,48 h后MTT检测舌鳞癌细胞的增殖能力;应用流式细胞仪技术和细胞免疫荧光技术检测细胞周期和细胞凋亡率;Western blot检测舌鳞癌细胞中MTUS1、p53、ERK1/2的表达情况。结果转染MTUS1/ATIP1后细胞的增殖明显受到抑制,其抑制率约为40％（t=0.023,P＜0.05）;高表达MTUS1/ATIP1可导致舌鳞癌细胞株G1期阻滞（G1期：t=0.032,G2期：t=0.036,S期：t=0.027,P＜0.05）并诱导细胞凋亡率的明显升高,差异具有统计学意义（t=0.005,P＜0.05）。 Western blot检测显示,转染MTUS1/ATIP1后ERK的表达升高,磷酸化的ERK表达下降,p53的表达升高。结论 MTUS1可抑制舌鳞癌细胞的增殖,诱导细胞凋亡。     

Silencing LINC01234 represses pancreatic cancer progression by inhibiting the malignant phenotypes of pancreatic cancer cells

ObjectivePrevious works have outlined the pivotal involvement of long intergenic non-coding RNA (lincRNA) in cancer progression, while the efficiency of LINC01234 in pancreatic cancer remained obscure. The purpose of this research is to unravel the regulatory mechanism of LINC01234 in pancreatic cancer via modulating microRNA (miR)-513a-3p and hexose 6-phosphate dehydrogenase (H6PD).MethodsPancreatic cancer cells were cultured and clinical tissue specimens were collected. LINC01234, miR-513a-3p and H6PD levels in pancreatic cancer cells and tissues were examined. Plasmids altering LINC01234, miR-513a-3p and H6PD expression were transfected into pancreatic cancer cells to assess the change in biological behaviors of pancreatic cancer cells. The targeting relations among LINC01234, miR-513a-3p and H6PD were validated.ResultsLINC01234 and H6PD levels were elevated while miR-513a-3p level was reduced in pancreatic cancer cells and tissues. LINC01234 deficiency hindered the malignant biological activities of pancreatic cancer cells. MiR-513a-3p depletion or H6PD elevation could abrogate the inhibitory effects of LINC01234 silencing on pancreatic cancer cells. LINC01234 sponged miR-513a-3p that targeted H6PD.ConclusionThe reduced LINC01234 exerts inhibitory impacts on pancreatic cancer cells via targeting miR-513a-3p to restrain H6PD level. The current study broadens the understanding of LINC01234 function and affords novel therapeutic targets for pancreatic cancer treatment.     

乙酰辅酶A羧化酶1对胶质瘤细胞系U87细胞增殖、迁移和侵袭的影响

目的 探讨乙酰辅酶A羧化酶1（ACC1）对人胶质瘤细胞系U87细胞增殖、迁移及侵袭的作用。 方法 Western blotting检测人胶质瘤细胞系U87、U251及U373中ACC1的表达;构建ACC1过表达质粒载体,将过表达ACC1质粒载体瞬时转染至U87细胞中;Western blotting检测转染后U87细胞中ACC1表达情况;MTT实验检测过表达ACC1对U87细胞增殖的影响;Transwell迁移和侵袭实验分别检测过表达ACC1对U87细胞迁移和侵袭的影响;划痕实验检测过表达ACC1对U87细胞划痕愈合能力的影响;Western blotting检测相关蛋白表达变化。 结果 与人胶质瘤细胞系U251和U373相比,U87细胞中ACC1表达较低;ACC1过表达抑制U87细胞增殖（P<0.01）;ACC1过表达抑制U87细胞迁移、侵袭和划痕愈合能力（P<0.01）;ACC1过表达迁移和侵袭相关蛋白波形蛋白(vimentin)、纤维连接蛋白(fibronectin)和尿激酶型纤溶酶原激活剂(uPA)表达下调（P<0.01）,凋亡抑制蛋白Bcl-2和细胞周期蛋白(cyclin) B、cyclin D表达下调（P<0.01）,p-STAT3蛋白表达下调（P<0.01）,细胞周期蛋白P21表达上调（P<0.01）。 结论 过表达ACC1可能通过抑制STAT3活性,抑制人胶质瘤细胞的增殖、迁移和侵袭。     

MicroRNA-1301 induces cell proliferation by downregulating ICAT expression in breast cancer

Breast cancer is one of the most common malignancies among gynecological diseases in the world and the long-term prognosis for breast cancer patients still remains dismal due to lack of effective early diagnosis biomarkers. Identifying sensitive and specific biomarkers in carcinogenesis may improve diagnostic and therapeutic strategies for this malignancy. Herein, we show that the expression of miR-1301 was markedly upregulated in breast cancer cell lines and tissues, and upregulation of miR-1301 enhanced, whereas downregulation of miR-1301 inhibited the proliferation of breast cancer cells in vitro. Furthermore, by biological approaches, we showed that miR-1301 directly targeted and suppressed ICAT expression, an important modulator of Wnt/β-Catenin pathway. These data suggests that miR-1301 may represent a novel therapeutic target of microRNA-mediated cell proliferation in breast cancer.     

Lipopolysaccharide potentiates endothelin-1-induced proliferation of pulmonary arterial smooth muscle cells by upregulating TRPC channels

Lipopolysaccharide (LPS) and endothelin-1 (ET-1) are critical pathogenic factors in sepsis-induced pulmonary hypertension; however it is unknown whether they have a coordinated action in the pathogenesis of this disease. Here we found that although LPS did not change the contractility of rat pulmonary arterial smooth muscle cells (PASMCs) in response to ET-1, it significantly promoted ET-1-induced PASMC proliferation. Measurement of ET-1-evoked Ca²⁺ transients in PASMCs showed that LPS dramatically enhanced Ca²⁺ influx mediated by transient receptor potential canonical (TRPC) channels. LPS did not directly activate TRPC channels, instead it selectively upregulated the expression of TRPC3 and TRPC4 in pulmonary arteries. Small interfering RNA (siRNA) and chemical blockers against TRPC channels abolished LPS-induced PASMC proliferation. LPS-induced cell proliferation and TRPC expression was mediated by the Ca²⁺-dependent calcineurin/NFAT signaling pathway. We suggest that blocking TRPC channels could be an effective strategy in controlling pulmonary arterial remodeling after endotoxin exposure.