Novel genetic variants in KIF16B and NEDD4L in the endosome-related genes are associated with nonsmall cell lung cancer survival

The endosome is a membrane-bound organ inside most eukaryotic cells, playing an important role in adaptive immunity by delivering endocytosed antigens to both MHC class I and II pathways. Here, by analyzing genotyping data from two published genome-wide association studies (GWASs), we evaluated associations between genetic variants in the endosome-related gene-set and survival of patients with nonsmall cell lung cancer (NSCLC). The discovery included 44,112 (3,478 genotyped and 40,634 imputed) single-nucleotide polymorphisms (SNPs) in 220 genes in a singlelocus analysis for their associations with survival of 1,185 NSCLC patients from the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial. After validation of the 821 survival-associated significant SNPs in additional 984 NSCLC patients from the Harvard Lung Cancer Susceptibility Study, 14 SNPs remained significant. The final multivariate stepwise Cox proportional hazards regression modeling of the PLCO dataset identified three potentially functional and independent SNPs (i.e., KIF16B rs1555195 C>T, NEDD4L rs11660748 A>G and rs73440898 A>G) with an adjusted hazards ratio (HR) of 0.86 (95% confidence interval [CI] = 0.79–0.94, p = 0.0007), 1.31 (1.16–1.47, p = 6.0 × 10⁻⁵) and 1.27 (1.12–1.44, p = 0.0001) for overall survival (OS), respectively. Combined analysis of the adverse genotypes of these three SNPs revealed a trend in the genotype-survival association (p_trend < 0.0001 for OS and p_trend < 0.0001 for disease-specific survival). Furthermore, the survival-associated KIF16B rs1555195T allele was significantly associated with decreased mRNA expression levels of KIF16B in both lung tissues and blood cells. Therefore, genetic variants of the endosome-related genes may be biomarker for NSCLC survival, possibly through modulating the expression of corresponding genes.     

Endoplasmic reticulum stress is involved in ventilator-induced lung injury in mice via the IRE1α-TRAF2-NF-κB pathway

Inflammation plays a critical role in the development of ventilator-induced lung injury (VILI). Endoplasmic reticulum (ER) stress is associated with a variety of diseases through the modulation of inflammatory responses. However, little is known about how ER stress is implicated in VILI. In this study, murine mechanical ventilation models were constructed. Total protein and inflammatory cytokines were measured in bronchoalveolar lavage fluid (BALF), and lung tissue injury was assessed by histology. Our data revealed that mice subjected to high tidal ventilation (TV) for 4 h showed more severe pulmonary edema and inflammation than those of mice with spontaneous breathing and low TV-treatment. In addition, the high TV-treated animals upregulated the ER stress markers GRP78, CHOP, p-IRE1α, TRAF2, and p-NF-κB expression at both the mRNA and protein levels in lung tissue. Administration of thapsigargin exacerbated the histological changes, inflammation and expression of GRP78 and CHOP after high TV, but treatment with ER stress and IRE1α kinase inhibitors attenuated the pathological damage and downregulated the high expression of GRP78, CHOP, p-IRE1α, TRAF2, and p-NF-κB, suggesting that ER stress is involved in VILI though the IRE1α/TRAF2/NF-κB signaling pathway in mice.     

嘌呤配体P2X门控离子通道型受体7及其下游分子在痛风性关节炎中作用机制的研究进展

目前随着痛风性关节炎的发病率逐年上升,对该病炎性反应及疼痛机制的研究越来越多,该病主要由尿酸盐沉积及ATP刺激P2X7R、Nod样受体蛋白3、NEK7表达诱导炎性反应递质成熟与分泌所致,但具体机制尚不明确。现对P2X7R、NLRP3、NEK7的国内外研究进展进行综述,以探讨GA炎性反应及疼痛的发病机制,为防治GA提供新思路与治疗靶点。     

Wnt/β-Catenin Signaling Pathway as Chemotherapeutic Target in Breast Cancer: An Update on Pros and Cons

The Wnt/β-catenin pathway, in addition to playing a crucial role in the development of the mammary gland during embryogenesis and during pregnancy, is one of the most commonly altered pathways in breast cancer. Accumulating findings from in vitro and in vivo and clinical studies have been suggestive of this pathway as a potential chemotherapy target. However, approved chemotherapeutic agents targeting this pathway are still missing for the treatment of patients with cancer. None of the clinical trials on the Wnt/β-catenin pathway inhibitors have translated beyond phase I/II studies. Hence, detailed analysis of the alterations in this pathway and the therapeutic agents modulating Wnt/β-catenin signaling components in breast cancer is warranted. The present review explored the latest developments in the association of deregulation in the Wnt/β-catenin signal cascade with the pathogenesis of breast cancer, the progress in identifying the potential chemotherapeutic drugs inhibiting this pathway, and the status of these compounds in clinical trials of breast cancer.     

口服蛋氨酸饲料致大鼠心室重塑的研究

目的:探讨口服蛋氨酸饲料致大鼠心力衰竭模型的机制，及程序性死亡因子4（PDCD4）通路在此过程中的作用。方法:5周龄健康Wistar雄性大鼠30只，适应性喂养1周后，随机分为实验组与对照组，实验组给予3%蛋氨酸饲料喂养，对照组标准饲料喂养。12周后进行血流动力学检测，采用酶联免疫法测定血清同型半胱氨酸（HCY）及N端前脑钠肽（NT-proBNP）水平，心脏彩超进行心功能评估，病理染色明确有无细胞肥大、纤维化，Western blot检测心肌组织中PDCD4蛋白的表达。结果:3%蛋氨酸饲料喂养组HCY水平较对照组升高（均P＜0.05）,心脏彩超提示3%蛋氨酸饲料喂养组大鼠左室射血分数、缩短分数、室间隔厚度显著减低（均P＜0.05），左室收缩末内径及舒张末内径较对照组显著增加（均P＜0.05），Western blot结果显示, PDCD4蛋白表达降低（P＜0.05）。结论:通过口服蛋氨酸饲料造成大鼠高HCY血症可导致大鼠出现心室重塑，并造成心功能受损，其机制可能与PDCD4信号通路的下调有关。     

Group testing in mediation analysis

We consider the scenario where there is an exposure, multiple biologically defined sets of biomarkers, and an outcome. We propose a new two-step procedure that tests if any of the sets of biomarkers mediate the exposure/outcome relationship, while maintaining a prespecified familywise error rate. The first step of the proposed procedure is a screening step that removes all groups that are unlikely to be strongly associated with both the exposure and the outcome. The second step adapts recent advances in postselection inference to test if there are true mediators in each of the remaining candidate sets. We use simulation to show that this simple two-step procedure has higher statistical power to detect true mediating sets when compared with existing procedures. We then use our two-step procedure to identify a set of Lysine-related metabolites that potentially mediate the known relationship between increased body mass index and the increased risk of estrogen-receptor positive breast cancer in postmenopausal women.     

七氟烷预处理对大鼠骨髓间充质干细胞在缺氧复氧环境下的作用和机制初探

目的:研究七氟烷预处理对大鼠骨髓间充质干细胞（MSCs）在缺氧复氧环境下的作用和机制初探。方法:分离培养SD大鼠骨髓间充质干细胞，通过流式细胞仪和诱导分化培养鉴定其免疫表型和分化潜能。细胞随机分为3组:组1空白对照组；组2缺氧复氧组（缺氧24 h，复氧24 h）；组3七氟烷预处理组（2%七氟烷预处理2 h后，缺氧24 h，复氧24 h）。处理后收集各组细胞，用流式细胞仪测定其凋亡率，线粒体膜电位变化及细胞周期。Western blot测定细胞外调节蛋白激酶（ERK）的蛋白表达。结果:与组2相比，组3 MSCs凋亡率明显下降，处于S期细胞增多，细胞增殖能力增强。Western blot结果显示:与组2相比，组3磷酸化ERK蛋白表达上升。结论:七氟烷预处理能提高缺氧复氧环境下骨髓间充质干细胞存活率，降低MSCs凋亡数量，并能增强MSCs的增殖能力，这一机制与七氟烷促进MSCs细胞p-ERK蛋白表达相关。     

基于SNP芯片研究PI3K/Akt/mTOR通路上自噬相关基因SNPs与胃癌的关联

目的： 探讨与胃癌发生相关的PI3K/Akt/mTOR通路上新的与自噬相关基因单核苷酸多态性位点（SNPs），为寻找有价值的胃癌发生相关的分子标志物提供新的依据。方法： 采用1：1配对病例-对照研究的方法。通过KEGG pathway网站和Gene Ontology、Ensemble数据库及HaploView、STRING、Cytoscape软件联合SNP芯片筛选目标SNPs，采用基质辅助激光解吸电离飞行时间质谱（MALDI-TOF-MS）对筛检出来的SNPs位点在来自福建省仙游县的622例胃癌患者和622例健康人群基因组中进行验证。结果： SNP芯片及生物信息学分析筛选出IRS1 rs10205233、PIK3CD rs3934934、PIK3R1 rs706711、PIK3R1 rs706714和AKT1 rs35285446为候选位点。扩大样本验证发现IRS1 rs10205233的多态性变异（C > T）显著降低了胃癌的发病风险[共显性模型、显性模型的OR（95% CI）分别为0.761（0.595，0.975）、0.764（0.601，0.973）]。进一步分层分析，该位点显性模型、隐形模型、共显性模型以及等位基因在贲门癌和非贲门癌人群中均未见统计学差异（P > 0.05）。并未见其他位点与患胃癌风险的关联有统计学意义。对PIK3R1基因2个位点（rs706711、rs706714）的单体型分析也未见统计学差异。结论： IRS1 rs10205233位点与福建省胃癌高发区仙游县的胃癌发生存在关联，T等位基因可能是胃癌发生的一个遗传保护因素。