宫颈癌新辅助化疗的临床应用及其疗效的评价

宫颈癌的新辅助化疗（NACT）是宫颈癌治疗的主要措施之一。近年来,对宫颈癌NACT前后细胞标志物水平变化的研究日益增多。结果显示其水平高低确与宫颈癌的治疗及预后相关,其表达差异可以用来预测宫颈癌对NACT的敏感性,为宫颈癌患者的治疗方案提供依据。     

白芍总苷对阿尔茨海默病的保护作用及机制的研究

目的探讨白芍总苷（total glucosides of paeony,TGP）对阿尔茨海默病（AD）的保护作用及其作用机制。方法实验共分为7组,分别为正常对照组（Control组）、模型组[连二亚硫酸钠（Na2S2O4）缺氧无保护组]及TGP各干预组（剂量分别为50、100、200、400、800mg／L）。采用Na2S2O4建立人神经母细胞瘤（SK—N—SH）细胞缺氧损伤模型,Na2S2O4于不同浓度TGP干预1h后加入,作用16h。利用倒置相差显微镜观察各组SK-N—SH细胞生长及形态的变化;采用四甲基偶氮唑盐（MTr）微量酶反应比色法测定各组SK—N—SH细胞的存活率;利用蛋白免疫印迹（western blot）法检测SK—N-SH细胞中半胱氨酸天冬氨酸蛋白酶-3（Caspase-3）的表达水平。结果形态学研究显示,正常对照组SK-N-SH细胞呈圆形,较少有突起,为贴壁细胞,折光性较强;模型组多数细胞肿胀,折光度减弱,最终细胞成团、漂浮,并有许多细胞崩解物,TGP各浓度组均较模型组细胞数量较多,折光性明显增强,细胞裂解碎片减少,多数细胞重新贴壁伸展;TGP100、200、400、800mg／L干预组能够有效改善SK-N—SH细胞缺氧损伤造成的细胞死亡率的增加;TGP50、100、200、400、800mg／L干预明显抑制SK—N—SH细胞缺氧损伤造成的Caspase-3蛋白表达的增加。结论TGP对AD具有明显的保护作用,其作用机制与通过调控Caspase-3蛋白的表达影响神经细胞的凋亡相关。     

单壁碳纳米管对小鼠N2a神经瘤细胞潜在毒性的探讨

目的探究单壁碳纳米管（single—wailed carbon nanotubes,SWCNTs）对小鼠成神经瘤细胞（N2a）的细胞毒性作用。方法采用不同浓度的SWCNTs悬液（0、12．5、25、50ug·ml-1）对N2a细胞进行24h染毒处理后,检测细胞活力,细胞活性氧（reactive oxygen species,ROS）、还原型谷胱甘肽（GSH）水平。结果随着N2a染毒浓度的增加,N2a细胞活力下降,ROS含量增加,GSH含量下降。在维生素C（Vitc）存在的情况下,最高浓度组（50ug·ml-1）产生的细胞损伤最大程度上得到缓解。结论SWCNTs的暴露在某种程度上可对N2a细胞产生一定的细胞毒性,并且VitC可以通过降低氧化损伤对N2a细胞起到一定的保护作用。     

Cell transplantation therapy for a rat model of secondary lymphedema

Background

Although lymphedema is a progressive and lifelong condition, substantial advances in therapeutic intervention are limited. The development of a novel therapy for lymphedema is urgent for those patients suffering from it. The aim of this study was to investigate the usefulness of a new cell transplantation therapy in the rat tail model of secondary lymphedema.

Materials and methods

We prepared two cell sources, human dermal microvascular endothelial cells (HDMECs) and lymphatic endothelial cells (LECs), which were collected from the resected normal dermis of patients with breast cancer. After the animal model of secondary lymphedema of the nude rats' tails was established, phosphate-buffered saline, purified LECs, or unpurified HDMECs were injected in the rats' tails five times for more than 14 d. The evaluations were performed by measuring the circumference, fluorescence lymphography, and histologic analysis of the rats' tails between each group.

Results

The isolated cells by the simple immunomagnetic sorting from HDMECs were positive for a pan-endothelial marker (CD31) and lymphatic-specific markers (podoplanin, lymphatic vessel endothelial hyaluronan receptor-1 [LYVE-1], and prospero homebox 1 [Prox-1]), and were considered to be LECs. In the cell transplantation group, which was injected with human LECs, the circumference, lymphatic flow, and thickness of the skin of the rat tail became thinner than the groups injected with unpurified HDMECs or phosphate-buffered saline. Immunohistochemistry of the rat tails showed that the number of own lymphatic vessels was increased in the purified LEC transplantation group compared with the other groups. Furthermore, in the LEC transplantation group, some vessels were immunopositive for human-podoplanin or -LYVE-1 and the areas adjacent to the vessels were rat-podoplanin or -LYVE-1 immunopositive.

Conclusions

Our findings indicate that cell transplantation therapy using human LECs improved the secondary lymphedema in the nude rat tail. This therapeutic strategy may merit clinical investigation in patients with lymphedema.     

Glutamine downregulates TLR-2 and TLR-4 expression and protects intestinal tract in preterm neonatal rats with necrotizing enterocolitis

Background/Purpose

Toll-like receptor (TLR)-4 and TLR-2 play an essential role in the pathogenesis of necrotizing enterocolitis (NEC). In this study, we investigated the protective effect of glutamine (Gln) in an NEC neonatal rat model, and the potential association with TLR-4 and TLR-2 expression in local intestinal tissues.

Methods

Preterm neonatal rats were randomly divided into 3 groups: normal control; NEC model; and NEC plus Gln intervention. NEC was induced by feeding with artificial milk substitutes, plus exposure to hypoxia and cold stress. All preterm rats were sacrificed at 3 days after birth. The intestinal tissues were taken for pathological analysis. Protein and mRNA expression of TLR-2, TLR-4, and caspase-3 was examined by immunohistochemistry and real-time RT-PCR, respectively.

Results

Compared with the normal control, the NEC neonatal rats showed mucosal injury and upregulated mRNA and protein expression of TLR-2, TLR-4, and caspase-3 in ileum and colon. Gln intervention significantly reduced the mucosal injury and suppressed the upregulated expression of TLR-2, TLR-4, and caspace-3 in the ileum and colon of NEC neonatal rats.

Conclusions

Gln protects the intestinal tract of NEC neonatal rats, which may be associated with the reduction of TLR-2 and TLR-4 expression in intestines     

MK2206 inhibits hepatocellular carcinoma cellular proliferation via induction of apoptosis and cell cycle arrest

Background

Hepatocellular carcinoma (HCC) is commonly diagnosed at an advanced stage and has limited effective treatment options. The aberrant regulation of the phosphoinositide 3-kinase/Akt pathway in HCC makes it an attractive therapeutic target. The effect of MK2206, a novel, allosteric Akt inhibitor, on HCC cells is not yet fully understood. We hypothesized that inhibition of Akt by MK2206 would impact cellular viability.

Materials and methods

Human Huh7, Hep3B, and HepG2 cell lines were treated with 0–2 μM of MK2206 for 96 h. Cell viability was determined by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Western blot analysis was used to examine the expression level of various protein markers to assess the mechanism of drug action and proliferation inhibition.

Results

3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed a reduction in cellular viability by ≥55% for all cell lines (control versus 2 μM MK2206; P <0.001). Western blot analysis revealed reduction in the level of phosphorylated AKT-Ser473 with no change in AKT-thr308 expression confirming the specificity of MK2206. There was an observed reduction in caspase-9 and survivin. Importantly, there were increases in p21 and p27 along with decreased cyclinD1 expression after treatment.

Conclusions

This study demonstrates the anti-tumor activity of MK2206 in HCC cells. The observed reduction in survivin and pro-caspase 9 suggests that MK2206 induces apoptosis. However, HCC proliferation is also halted via induction of cell cycle arrest as indicated by the increase in p21 and p27 expression and decrease in cyclinD1. Importantly, the concentration needed to achieve growth inhibition in HCC is lower than that needed for other cancer types.     

Therapeutic potential of transgenic mesenchymal stem cells engineered to mediate anti–high mobility group box 1 activity: targeting of colon cancer

Background

Mesenchymal stem cells (MSCs) are being developed as a new clinically relevant stem cell type to be recruited into and to repair injured tissue. A number of studies have focused on the therapeutic potential of MSCs by virtue of their immunomodulatory properties. Systemically administered MSCs can also migrate to sites of malignancies. Because of this latter phenomenon, we transfected human MSCs to secrete anti–high mobility group box (HMGB) 1 proteins. They were then injected into mice bearing human colon cancer to evaluate their efficacy as an antineoplastic agent.

Materials and methods

The ABOX gene was used in this model, which encodes part of the HMGB1 protein and acts as an HMGB1 antagonist. It was cotransduced by electroporation with a FLAG-tag to visualize the secreted ABOX protein, levels of which in supernatants from cultured transfected MSCs were quantified by immunofluorescence imaging using an anti-FLAG antibody. Antiangiogenic effects were evaluated in vitro using a novel optical assay device for the quantitative measurement of cellular chemotaxis assessing the velocity and direction of endothelial cell movement stimulated by supernatant from tumor cells. We found that ABOX proteins released from transfected MSCs suppressed migration in this assay. Finally, MSCs were injected subcutaneously into Nonobese diabetic/severe combined immunodeficiency mice bearing human colon cancer from a cell line, which secreted large amounts of HMGB1. Ten days after MSC injection, mice were sacrificed and tumors evaluated by immunohistochemistry.

Results

From 12 ho through 7 d after gene transfection, ABOX proteins secreted from MSCs could be detected by immunofluorescence and enzyme-linked immunosorbent assay. Quantitative measurement of cellular chemotaxis demonstrated that ABOX proteins secreted from transfected MSCs decreased the velocity and interfered with the direction of movement of vascular endothelial cells. Moreover, in an in vivo human colon cancer xenograft model, injection of anti-HMGB1–transfected MSCs resulted in a decreased tumor volume due to the antiangiogenic properties of the secreted ABOX proteins.

Conclusions

MSC modified to secrete HMGB1 antagonist proteins have therapeutic antineoplastic potential. These findings may contribute to future novel targeting strategies using autologous bone marrow–derived cells as gene delivery vectors.     

微卫星与肺重复癌的研究进展

微卫星（microsatellite,MS）是指以少数几个核苷酸（多为2～4个）为单位多次串联重复的DNA序列。肺重复癌（肺多原发癌,multiple primary lung cancer）是指一侧肺或两侧肺的不同部位发生两个或两个以上原发癌,其组织类型相同或不同,但各肿瘤之间无从属关系,每个肿瘤的发生有着各自独立的成瘤因素。微卫星异常与肺重复癌的发生及发展密切相关。本文主要综述：1微卫星的概念及产生机制;2微卫星异常;3肺重复癌的概念及分类;4微卫星对肺重复癌的早期诊断和预后治疗的影响。     

The role of mRNA splicing in prostate cancer

Alternative splicing （AS） is a crucial step in gene expression. It is subject to intricate regulation, and its deregulation in cancer can lead to a wide array of neoplastic phenotypes. A large body of evidence implicates splice isoforms in most if not all hallmarks of cancer, including growth, apoptosis, invasion and metastasis, angiogenesis, and metabolism. AS has important clinical implications since it can be manipulated therapeutically to treat cancer and represents a mechanism of resistance to therapy. In prostate cancer （PCa） AS also plays a prominent role and this review will summarize the current knowledge of alternatively spliced genes with important functional consequences. We will highlight accumulating evidence on AS of the components of the two critical pathways in PCa： androgen receptor （AR） and phosphoinositide 3-kinase （PI3K）. These observations together with data on dysregulation of splice factors in PCa suggest that AR and PI3K pathways may be interconnected with previously unappreciated splicing regulatory networks. In addition, we will discuss several lines of evidence implicating splicing regulation in the development of the castration resistance.     

NP方案加同期照射对人肺腺癌细胞存活的影响

目的 探讨NP方案加同期照射对人肺癌细胞增殖和凋亡的影响.方法 以A549、H1299为实验对象,设单纯照射组（A组）、酒石酸长春瑞滨＋顺铂＋同期照射组（B组）,再按照照射剂量不同分为A-0、A-4、A-8组和B-0、B-4、B-8组.MTT方法用于检测酒石酸长春瑞滨＋顺铂＋同期照射对细胞增殖的影响,FACS用于检测酒石酸长春瑞滨＋顺铂＋同期照射对细胞凋亡的影响和细胞表面P-gp表达的影响.结果 除B-0组在48 h细胞抑制率与A-0组比较差异无统计学意义（P=0.103）外,B-0、B-4和B-8组在6,12,24和48 h时细胞抑制率均显著低于A-0、A-4和A-8组,差异均有统计学意义（P＜0.01）.A-0组细胞凋亡率（4.01±0.95）％,A-4组为（20.19±3.76）％,A-8组为（45.34±4.77）％.A-8组细胞凋亡率显著高于A-4组,A-4组细胞凋亡率显著高于A-0组,差异均有统计学意义（t =7.17,P=0.006;t=7.23,P=0.019）.B-0组细胞凋亡率（14.78±2.37）％,B-4组为（36.18±4.73）％,B-8组为（51.12±3.37）％.B-8组细胞凋亡率显著高于B-4组,B-4组细胞凋亡率显著高于B-0组,B-0组细胞凋亡率显著高于A-0组,B-4组细胞凋亡率显著高于A-4组,差异均有统计学意义（t=3.59,P=0.037;t=9.00,P=0.003;t=7.31,P=0.018;t=4.58,P=0.020）,B-8组细胞凋亡率与A-8组比较差异无统计学意义（t=1.71,P=0.185）.A-0组S周期细胞比例为（10.61±2.23）％,A-4组为（14.75±3.02）％,A-8组为（21.81±2.94）％;B-0组S周期细胞比例为（19.27±2.97）％,B-4组为（26.23±2.12）％,B-8组为（32.37±3.53）％.B-0、B-4和B-8组S周期细胞比例分别显著高于A-0、A-4和A-8组,差异均有统计学意义（t=4.04,P=0.027;t=5.35,P=0.013;t=3.98,P=0.028）.A-0、A-4和A-8组P-gp荧光强度分别为（7.32±0.75）、（6.57±0.93）、（6.32±0.86） MFI,差异无统计学意义（P＞0.05）.B-0、B-4和B-8组P-gp荧光强度分别为（5.12±0.81）、（3.76±0.74）、（2.16±0.24） MFI.B-0组P-gp荧光强度显著低于A-0组,B-4组P-gp荧光强度显著低于A-4组,B-8组P-gp荧光强度显著低于A-8组,差异均有统计学意义（t=-3.45,P=0.041;t=-5.85,P=0.010;t=-8.07,P=0.015）.B-4组P-gp荧光强度显著低于B-0组,差异有统计学意义（t=-8.07,P=0.015）,且与B-8组比较差异无统计学意义（t=-3.56,P=0.071）.结论 NP方案加同期照射可以显著抑制人肺癌细胞增殖和凋亡,且降低肺癌细胞表面P-gp的表达.