食管鳞状细胞癌发生发展过程中环氧合酶-2表达的研究

目的　研究环氧合酶 2 (cyclooxygenase 2 ,cox 2 )在正常食管黏膜、食管黏膜鳞状上皮不典型增生和食管鳞状细胞癌组织中的表达 ,探讨cox 2在食管鳞状细胞癌发生发展中的作用。方法　用免疫组织化学染色和蛋白质免疫印迹方法检测 86例食管鳞癌、4 7例食管黏膜鳞状上皮不典型增生和 4 2例癌周正常组织cox 2的表达。结果　食管鳞状细胞癌、食管黏膜鳞状上皮不典型增生组织中cox 2表达显著增高 ,免疫组织化学染色积分分别为 2 .6 7± 1.77和 2 .19± 1.79,而正常食管黏膜组织的cox 2无表达或表达极弱 ,免疫组织化学染色积分为 0 .71± 0 .4 6。蛋白质免疫印迹检测的结果与免疫组织化学的检测结果相似。在食管鳞状细胞癌、食管黏膜鳞状上皮不典型增生组织中 ,cox 2表达与细胞增殖活力显著相关 ,而在正常食管黏膜组织中二者无相关关系。食管鳞状细胞癌cox 2的表达与其临床病理特征如年龄、性别、癌肿大小、分化程度、临床分期、淋巴结是否转移等无关。结论　cox 2在食管黏膜鳞状上皮不典型增生和食管鳞状细胞癌组织中表达增高 ,并与细胞增殖活力有关 ,提示cox 2在食管鳞状细胞癌发生发展过程中起重要作用。     

Effects of natural raw meal (NRM) on high-fat diet and dextran sulfate sodium (DSS)-induced ulcerative colitis in C57BL/6J mice

BACKGROUND/OBJECTIVESColitis is a serious health problem, and chronic obesity is associated with the progression of colitis. The aim of this study was to determine the effects of natural raw meal (NRM) on high-fat diet (HFD, 45%) and dextran sulfate sodium (DSS, 2% w/v)-induced colitis in C57BL/6J mice.MATERIALS/METHODSBody weight, colon length, and colon weight-to-length ratio, were measured directly. Serum levels of obesity-related biomarkers, triglyceride (TG), total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein (HDL), insulin, leptin, and adiponectin were determined using commercial kits. Serum levels of pro-inflammatory cytokines including tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6 were detected using a commercial ELISA kit. Histological study was performed using a hematoxylin and eosin (H&E) staining assay. Colonic mRNA expressions of TNF-α, IL-1β, IL-6, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) were determined by RT-PCR assay.RESULTSBody weight and obesity-related biomarkers (TG, TC, LDL, HDL, insulin, leptin, and adiponectin) were regulated and obesity was prevented in NRM treated mice. NRM significantly suppressed colon shortening and reduced colon weight-to-length ratio in HFD+DSS induced colitis in C57BL/6J mice (P < 0.05). Histological observations suggested that NRM reduced edema, mucosal damage, and the loss of crypts induced by HFD and DSS. In addition, NRM decreased the serum levels of pro-inflammatory cytokines, TNF-α, IL-1β, and IL-6 and inhibited the mRNA expressions of these cytokines, and iNOS and COX-2 in colon mucosa (P < 0.05).CONCLUSIONThe results suggest that NRM has an anti-inflammatory effect against HFD and DSS-induced colitis in mice, and that these effects are due to the amelioration of HFD and/or DSS-induced inflammatory reactions.     

Syntheses of 4-(indole-3-yl)quinazolines: a new class of epidermal growth factor receptor tyrosine kinase inhibitors

The epidermal growth factor (EGF) family of membrane receptors has been identified as a key element in the complex signaling network that is utilized by various classes of cell-surface receptors. The synthesis and pharmacological results of 4-(indole-3-yl)quinazolines are described. The synthesized compounds are new high potent EGFR-tyrosine kinase inhibitors with excellent cytotoxic properties at different cell lines. Furthermore the 4-(indole-3-yl)quinazolines show some tendencies to inhibit the HER-2 TK, too. Moreover this substance class has remarkable strong fluorescence properties.     

Synthesis and anti-tumor activity of 2-amino-3-cyano-6-(1H-indol-3-yl)-4-phenylpyridine derivatives in vitro

A series of novel 2-amino-3-cyano-6-(1H-indol-3-yl)-4-phenylpyridine derivatives were synthesized and their cytotoxic activity against A549, H460, HT-29 and SMMC-7721 cell lines was evaluated in vitro. Among them, ten compounds (10, 11, 14, 16, 17, 26, 27, 29, 30 and 31) displayed excellent anti-tumor activity against different cell lines. The most promising compound 27 showed strong anti-tumor activity against A549, H460, HT-29 and SMMC-7721 cell lines with IC₅₀ values of 22, 0.23, 0.65 and 0.77 nM, which were 2.6-, 83-, 1.1 × 10³- and 2.0 × 10³- fold more active than MX-58151 (IC₅₀ values of 0.058, 0.019, 0.70 and 1.53 μM), respectively.     

Inhibition of PDGFR tyrosine kinase activity by a series of novel N-(3-(4-(pyridin-3-yl)-1H-imidazol-2-ylamino)phenyl)amides: a SAR study on the bioisosterism of pyrimidine and imidazole

A series of N-(3-(4-(pyridin-3-yl)-1H-imidazol-2-ylamino)phenyl)amides were synthesized and tested for inhibition of PDGFR and FLT3 autophosphorylation. The novel N-(3-(4-(pyridin-3-yl)-1H-imidazol-2-ylamino)phenyl)amides, obtained by replacement of the pyrimidine system in Imatinib (1) with an imidazole ring, exhibit potent inhibitory activity on PDGFR, similar to the parent compound (IC(50) (9e)=0.2 microM; IC(50) Imatinib (1)=0.3 microM). Selectivity hereby seems to be conserved, as shown by the lack of activity on FLT3, a closely related class III receptor tyrosine kinase, which is not affected by the parent compound Imatinib.     

2010-2013年中山市流感病毒(H3N2)血凝素基因特征分析

目的研究中山市2010-2013年流行的H3N2亚型流感病毒的血凝素基因特征,分析其基因变异情况。方法选取2010-2013年中山市流行的H3N2亚型流感病毒6株,用MDCK细胞分离病毒,提取病毒RNA,RT-PCR扩增HA基因并测定序列,利用BLASTn对序列进行相似性检索,分析其与疫苗株,不同年份、区域流行株的进化变异情况。结果共分离鉴定到6株H3N2亚型流感病毒,其中2株为2010年流行株,2株为2012年流行株,2株为2013年流行株。各年流行株与其他国家或地区当年大部分流行株在一个分支上,其进化距离随着进化时间变长而变远。2012年流行株相对2010年流行株在HA1区发生12个氨基酸位点变异,有3个位于B、C区。2013年流行株相对2012年流行株发生4个氨基酸位点变异,有2个位于A区。2012年、2013年流行株相对于疫苗株分别发生6、8个氨基酸位点变异,分别有2、4个位于A、B、C区。受体结合位点未发生变异。结论中山市H3N2亚型流感病毒流行株在年度之间存在一定变异程度,进化距离随着进化时间变长而变远,相对于疫苗株也存在一定程度上的变异。     

甲状旁腺素、维生素D_3对Caco-2细胞钙结合蛋白D9k mRNA表达的影响

目的探讨甲状旁腺素(PTH)对小肠细胞钙结合蛋白(CaBP)D9k mRNA表达的影响以及探讨PTH是否影响1,25-(OH)2-D3对Caco-2细胞钙结合蛋白D9k mRNA表达的促进作用。方法以人结肠癌上皮细胞株Caco-2细胞作为小肠细胞体外模型,PTH分三个剂量10-8、10-9和10-12mol/L分别干预Caco-2细胞5、10、20、40和80min;10-8mol/L1,25-(OH)2-D3干预Caco-2细胞2、4、8、16和24h,溶剂对照为0.1%乙醇;10-8mol/L1,25-(OH)2-D3联合以上三剂量PTH干预Caco-2细胞2、4、8、16和24h,溶剂对照亦为0.1%乙醇。运用RT-PCR方法进行CaBP-D9k mRNA测定,以GAPDH作为内对照。结果10-8mol/LPTH作用20min,10-12mol/L作用10min,CaBP-D9k mRNA表达量高于空白组,其余时间点低于空白组;10-8mol/L1,25-(OH)2-D3干预Caco-2细胞2、4、8、16和24h,CaBP-D9k mRNA的表达均高于溶剂对照(0.1%乙醇);与10-8mol/L1,25-(OH)2-D3单独作用比较,10-8mol/L1,25-(OH)2-D3联合以上三剂量PTH作用,CaBP-D9k mRNA相对表达量均低于单独作用的表达量。结论10-8mol/L、10-12mol/LPTH可能促进Caco-2细胞CaBP-D9k mRNA瞬时(1~20min)合成增加;10-8mol/L1,25-(OH)2-D3可明显诱导Caco-2细胞CaBP-D9k mRNA的表达;PTH可能抵消或者抑制1,25-(OH)2-D3促进Caco-2细胞CaBP-D9k mRNA表达的作用。     

Effect of a prodrug of the green tea polyphenol (-)-epigallocatechin-3-gallate on the growth of androgen-independent prostate cancer in vivo

Epigallocatechin-3-gallate (EGCG) is the major and most potent polyphenol compound of green tea that has been shown to have anticancer effects against various types of cancers. In this study, in addition to the EGCG compound, a synthetic derivative, the peracetate of EGCG (EGCG-P), was used to investigate the inhibitory effects on growth of androgen-independent prostate cancer in vivo. The advantage of EGCG-P is that it may act as a prodrug, leading to higher bioavailability than EGCG itself. The aim of our study was to compare the differences between EGCG and EGCG-P on their inhibitory effect on androgen-independent prostate cancer, CWR22R, xenograft model in nude mice. The mice were administrated daily with solvent dimethyl sulfoxide, EGCG, and EGCG-P separately through intraperitoneal injection for 20 days. Tumor volume and body weight of nude mice were recorded daily. Serum prostate-specific antigen (PSA) levels were also measured before and after the treatment. The effects of both EGCG and EGCG-P on tumor cell proliferation were assessed by immunohistochemical (IHC) method using antibodies against Ki-67 and proliferating cell nuclear antigen. The apoptotic effect was evaluated by IHC against B-cell non-Hodgkin lymphoma-2 and terminal deoxynucleotidyl transferase dUTP nick-end labeling assay by in situ apoptosis detection kit. Moreover, the potential suppression of angiogenesis by EGCG and EGCG-P on prostate cancer was examined by IHC against CD31. Our results revealed that treatment of EGCG and EGCG-P compounds suppressed the growth of CWR22R xenografts without causing any detectable side effects in nude mice. The suppression of growth of the tumor was correlated with the decrease of serum PSA level together with the reduction in tumor angiogenesis and an increase in apoptosis on prostate cancer cells. The results showed that treatment of EGCG and EGCG-P inhibited tumor growth and angiogenesis while promoting apoptosis of the prostate cancer cells in vivo. Our results suggest that EGCG-P may be a more stable and useful compound for increasing the therapeutic anticancer effects in androgen-independent prostate cancer.     

Pharmacophore modeling and virtual screening for the discovery of new transforming growth factor-β type I receptor (ALK5) inhibitors

Inhibitors of transforming growth factor-β Type I Receptor (ALK5) have been thought as potential drugs for the treatment of fibrosis and cancer and a considerable number of ALK5 inhibitors have been reported recently. In order to clarify the essential structure–activity relationship for the known ALK5 inhibitors as well as identify new lead compounds against ALK5, 3D pharmacophore models have been established based on the known ALK5 inhibitors. The best pharmacophore model, Hypo1, was used as a 3D search query to perform a virtual screening. The hit compounds were subsequently subjected to filtering by Lipinski's rule of five and docking studies to refine the retrieved hits. Finally a total of 100 compounds were obtained and some of them were selected for further in vitro and in vivo assay studies.     

不同粒径纳米Fe2O3的细胞毒性及氧化作用

目的 从细胞半数抑制浓度ICso和氧化作用的角度探讨不同粒径Fe2O3纳米粒子细胞毒性的差异。方法 将8，13和37nm3个不同尺寸的Fe2O3纳米粒子以不同剂量、时间作用于中国仓鼠肺成纤维细胞(CHL)，用活细胞计数法求得不同尺寸粒子的IC50并绘制细胞生长抑制曲线。硫代巴比妥酸法测定丙二醛(MDA)含量，黄嘌呤氧化酶法测定超氧化歧化酶(SOD)活性。结果 (1)3种尺寸的纳米粒子在一定浓度范围内，剂量与细胞抑制率呈现剂量-反应关系，而超过这一范围后，量效关系消失。(2)在量效相关的浓度范围内，3种尺寸纳米粒子的IC50分别为IC50(8nm)=279．585μg／ml，IC50(13nm)=254．739μg/ml，IC50(37nm)=561．237μg/ml。(3)Fe2O3纳米粒子可引起CHL细胞的氧化应激反应，且与作用时间有关。但MDA、SOD值变化与纳米粒子尺才、作用剂量之间无明显的量效关系。结论 不同粒径的Fe2O3纳米粒子在细胞毒性上表现出一定的差异，Fe2O3纳米粒子可引起CHL细胞的氧化应激反应，从时效性分析推论其细胞毒性与氧化性存在一定的关联。