Molecular targeted therapy for advanced hepatocellular carcinoma

Systemic anticancer therapy for hepatocellular carcinoma (HCC) is limited by intrinsic drug resistance and accompanying liver dysfunction. However, recent advances in molecular targeted therapy (MTT) have shed light on the treatment of advanced HCC. A recent randomized, placebo-controlled trial demonstrated that sorafenib, a multi-target tyrosine kinase inhibitor, prolonged overall survival and time-to-progression in patients with advanced HCC. This breakthrough highlights the potential of MTT targeting hepatocarcinogenic pathways, such as the Raf/MAPK/ERK pathway, angiogenic pathways and the EGFR signaling pathway. This review discusses the current status and the potential of developing novel MTTs for advanced HCC.     

半乳糖-半乳糖胺检测法在大肠癌筛选中的应用

应用半乳糖-半乳糖胺检测法对118份直肠粘液标本作了检查。在30例大肠癌病人中其阳性率达90％,在65例肠粘膜正常人中,其阴性率达92.3％;另外20例大肠息肉病人中,其阳性率为15％,3例溃疡性结肠炎病人中阳性率为66.7％。结果表明:该法有较高的敏感性(90％)和特异性(92.3％),方法简便,结果易重复,在大肠癌普查中具有较大的应用潜力;在大肠息肉和溃疡结肠性炎中也有一定的阳性率,提示该法可用于某些大肠癌癌前状态恶变的监测。     

Loss of LFA-1, but not Mac-1, protects MRL/MpJ-Fas(lpr) mice from autoimmune disease

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by immune complex-mediated tissue injury. Many different adhesion molecules are thought to participate in the development of SLE; however, few studies have directly examined the contributions of these proteins. Here we demonstrate that LFA-1 plays an essential role in the development of lupus in MRL/MpJ-Fas(lpr) mice. Mice deficient in LFA-1, but not Mac-1, showed significantly increased survival, decreased anti-DNA autoantibody formation, and reduced glomerulonephritis. The phenotype of the LFA-1-deficient mice was similar to that observed in beta(2) integrin-deficient (CD18-null) MRL/MpJ-Fas(lpr) mice, suggesting a lack of redundancy among the beta(2) integrin family members and other adhesion molecules. These studies identify LFA-1 as a key contributor in the pathogenesis of autoimmune disease in this model, and further suggest that therapeutic strategies targeting this adhesion molecule may be beneficial for the treatment of SLE.     

Alterations of plasma antioxidants and mitochondrial DNA mutation in hair follicles of smokers

The effects of long-term smoking on mitochondrial DNA (mtDNA) deletions in hair follicles were investigated in subjects with different antioxidant capacity. Twenty-two male smokers with a smoking index of greater than 5 pack-years and without any known systemic diseases were recruited for this study. Forty healthy nonsmoking males were included as controls. We found that the concentrations of ascorbate and alpha-tocopherol and the activities of glutathione S-transferase (GST) and glutathione peroxidase in blood plasma were significantly decreased in smokers. The levels of glutathione and protein thiols in whole blood and the incidence of a 4,977 bp deletion of mtDNA (dmtDNA) in hair follicles were significantly increased in smokers. A significantly higher incidence of the 4,977 bp dmtDNA was found in smokers with plasma GST activity less than 5.66 U/l (OR = 7.2, P = 0.020). Using multiple covariate ANOVA and logistic regression, we found that age and low plasma GST activity were the only two risk factors for the 4,977 bp dmtDNA. These results suggest that smoking depletes antioxidants and causes mtDNA deletions and that plasma GST may play an important role in the preservation of the mitochondrial genome in tissue cells of smokers.     

Selenium and cancer chemoprevention: hypotheses integrating the actions of selenoproteins and selenium metabolites in epithelial and non-epithelial target cells

The trace element nutrient selenium (Se) discharges its well-known nutritional antioxidant activity through the Se-dependent glutathione peroxidases. It also regulates nuclear factor activities by redox mechanisms through the selenoprotein thioredoxin reductases. Converging data from epidemiological, ecological, and clinical studies have shown that Se can decrease the risk for some types of human cancers, especially those of the prostate, lung, and colon. Mechanistic studies have indicated that the methylselenol metabolite pool has many desirable attributes of chemoprevention, targeting both cancer cells and vascular endothelial cells, whereas the hydrogen selenide pool in excess of selenoprotein synthesis can lead to DNA single strand breaks, which may be mediated by some reactive oxygen species. We propose a new paradigm based on a consideration of the post-initiation biology of avascular early lesion expansion microenvironment, physiochemistry of Se delivery, and the obligatory need for angiogenesis to sustain lesion progression. Our model integrates the roles of selenoproteins and specific Se metabolites to account for cancer risk reduction or enhancement. For future studies, speciation (profiling) methods for Se metabolites and for Se forms in foods and supplements are much needed for hypothesis testing and for the development of mechanism-based Se status markers for cancer prevention. Randomized cancer prevention trials are necessary to test the efficacy of methyl selenium compounds.     

Nonminimum phase non-Gaussian autoregressive processes

The structure of non-Gaussian autoregressive schemes is described. Asymptotically efficient methods for the estimation of the coefficients of the models are described under appropriate conditions, some of which relate to smoothness and positivity of the density function f of the independent random variables generating the process. The principal interest is in nonminimum phase models.     

Andrographolide mitigates cardiac apoptosis to provide cardio‐protection in high‐fat‐diet‐induced obese mice

Excessive intake of high fat diet (HFD) and associated obese conditions are critical contributors of cardiac diseases. In this study, an active metabolite andrographolide from Andrographis paniculata was found to ameliorate HFD‐induced cardiac apoptosis. C57/BL6 mouse were grouped as control (n = 9), obese (n = 8), low dose (25 mg/kg/d) andrographolide treatment (n = 9), and high dose (50 mg/kg/d) andrographolide treatment (n = 9). The control group was provided with standard laboratory chow and the other groups were fed with HFD. Andrographolide was administered through oral gavage for 1 week. Histopathological analysis showed increase in apoptotic nuclei and considerable cardiac‐damages in the obese group signifying cardiac remodeling effects. Further, Western blot results showed increase in pro‐apoptotic proteins and decrease in the proteins of IGF‐1R‐survival signaling. However, feeding of andrographolide significantly reduced the cardiac effects of HFD. The results strongly suggest that andrographolide supplementation can be used for prevention and treatment of cardiovascular disease in obese patients.     

NRP1基因敲除对放射性肺纤维化进程的影响及其作用机制

目的：观察神经菌毛蛋白1（NRP1）基因对放射性肺纤维化（RIPF）进程的影响,并探讨其在Wnt/β-连环蛋白（β-catenin）信号通路和转化生长因子β1（TGF-β1）/Smads通路介导的上皮间质转化（EMT）发生发展过程和细胞外基质（ECM）沉积中的作用。方法：利用Cre-LoxP重组酶系统构建肺泡Ⅱ型上皮细胞（AT-Ⅱ）特异性敲除NRP1基因的转基因C57BL/6J小鼠并进行鼠尾鉴定,将160只小鼠按照射后不同时间点随机分为4周组、8周组、16周组和24周组,每组小鼠按随机数字表法分为野生型（Con）组、野生型单纯照射（IR）组、NRP1基因特异性敲除（KO-Con）组和NRP1基因特异性敲除+照射（KO+IR）组,每亚组10只。KO-Con和KO+IR组小鼠腹腔注射他莫昔芬特异性敲除AT-Ⅱ细胞NRP1基因,IR组和KO+IR组小鼠采用20 Gy全胸照射建立RIPF小鼠模型。模型构建完成后,利用HE染色法和Masson染色法验证模型是否构建成功;利用免疫组织化学（IHC）法检测小鼠肺组织中Ⅰ型胶原（Col Ⅰ）和α平滑肌肌动蛋白（α-SMA）的蛋白表达水平;Western blotting法检测小鼠肺组织中NRP1、β-catenin、TGF-β1和Smad2蛋白表达水平;实时荧光定量-聚合酶链反应（qRT-PCR）法检测小鼠肺组织中NRP1、Col Ⅰ、α-SMA、β-catenin、TGF-β1、Smad2、上皮型钙黏蛋白（E-cadherin）、神经型钙黏蛋白（N-cadherin）和波形蛋白（Vimentin）mRNA表达水平。结果：HE染色和Masson染色显示RIPF小鼠模型构建成功,IR组小鼠肺部主要为放射性肺炎病理形态表现。与Con组比较,随时间的延长,IR组小鼠肺组织中NRP1蛋白和mRNA表达水平逐渐升高（P<0.05）,24周时达到最高（P<0.01）。与Con组比较,随时间的延长IR组和KO+IR组小鼠肺组织中Col Ⅰ、α-SMA、β-catenin、TGF-β1和Smad2蛋白及mRNA表达水平逐渐升高（P<0.05或P<0.01）;与IR组比较,随时间的延长,KO+IR组小鼠肺组织中Col Ⅰ、α-SMA、β-catenin、TGF-β1和Smad2蛋白和mRNA表达水平均明显降低（P<0.05或P<0.01）,但仍高于Con组（P<0.05或P<0.01）。与Con组比较,随时间的延长,IR组和KO+IR组小鼠肺组织中上皮细胞标志物E-Cadherin mRNA表达水平逐渐降低（P<0.05）,间质细胞标志物N-Cadherin和Vimentin蛋白表达水平升高（P<0.05或P<0.01）,但KO+IR组小鼠肺组织中E-CadherinmRNA表达水平明显高于IR组（P<0.05或P<0.01）,N-Cadherin和Vimentin mRNA表达水平均明显低于IR组（P<0.05或P<0.01）。结论：NRP1基因敲除可抑制RIPF的发生发展,其机制可能与调节小鼠肺组织中Wnt/β-catenin和TGF-β1/Smads信号通路的表达进而抑制EMT进程有关。     

不同生长年限重庆庙党3种成分的动态变化

目的 研究不同生长年限重庆庙党3种活性成分的动态变化,为庙党的标准化种植、采收及质量控制等提供参考。方法 采用UV方法测定取1～5年生重庆庙党多糖及总皂苷的含量变化,采用HPLC方法测定党参炔苷的含量变化。结果 重庆庙党1～4年生长过程中,多糖含量随着生长年限的增加而增大,与第1年比较,第4年增长约100%,第5年增长约90%（第5年与第4年比较,负增长10%）;总皂苷及党参炔苷呈逐年递增趋势,第5年总皂苷合计增长约57%,党参炔苷合计增长约42%。重庆庙党生长过程中多糖、总皂苷及党参炔苷三者含量无明显相关性。结论 考虑活性成分的增长趋势、生产成本、生产效率、药材产量等因素,重庆庙党种植4年采收即可。