Overexpression of the PDZ1 domain of PSD‐95 diminishes ischemic brain injury via inhibition of the GluR6·PSD‐95·MLK3 pathway

Recent studies have shown that kainate (KA) receptors are involved in neuronal cell death induced by seizure, which is mediated by the GluR6·PSD‐95·MLK3 signaling module and subsequent JNK activation. In our previous studies, we demonstrated the neuroprotective role of a GluR6 c‐terminus containing peptide against KA or cerebral ischemia‐induced excitotoxicity in vitro and in vivo. Here, we first report that overexpression of the PDZ1 domain of PSD‐95 protein exerts a protective role against neuronal death induced by cerebral ischemia‐reperfusion in vivo and can prevent neuronal cell death induced by oxygen‐glucose deprivation. Further studies show that overexpression of PDZ1 can perturb the interaction of GluR6 with PSD‐95 and suppress the assembly of the GluR6·PSD‐95·MLK3 signaling module and therefore inhibit JNK activation. Thus, it not only inhibits phosphorylation of c‐Jun and down‐regulates Fas ligand expression but also inhibits phosphorylation of 14‐3‐3 and decreases Bax translocation to mitochondria, decreases the release of cytochrome c, and decreases caspase‐3 activation. Overall, the essential role of the PDZ1 domain of PSD‐95 in apoptotic cell death in neurons provides an experimental foundation for gene therapy of neurodegenerative diseases with overexpression of the PDZ1 domain. © 2009 Wiley‐Liss, Inc.     

食管鳞癌中人表皮生长因子受体Her-2/neu蛋白的过表达及预后意义

目的 分析食管鳞癌中Her-2/neu蛋白过表达的临床病理意义及其对预后的影响,探讨以Her-2/neu单抗对过表达Her-2/neu蛋白的食管鳞癌患者进行靶向治疗的可行性.方法 应用Hercep Test 试剂盒,对94例外科切除、病理诊断为食管鳞癌的标本中Her-2/neu蛋白的表达水平进行检测,并分析Her-2/neu蛋白的过表达与临床病理特征的关系以及与患者预后的关系.结果 HER-2/neu蛋白在癌旁组织及正常食管组织中的表达为阴性,在94例食管鳞癌中的过表达率为20.2%(19/94),其过表达与患者的性别、年龄、肿瘤部位、组织学分化程度、临床分期均无明显相关性(P>0.05),而与肿瘤浸润深度(T分期)以及淋巴结转移(N分期)具有一定的相关性.在T3+T4期的肿瘤组织中的过表达率明显高于T1+T2期的肿瘤组织中的过表达率(30.0% vs.13.0%),差异有统计学意义(χ~2=4.136,P=0.039);在N1期肿瘤组织中的过表达率明显高于在NO期肿瘤组织中的过表达率(26.8%vs.10.6%),差异有统计学意义(χ~2=3.711,P=0.045);生存分析显示HER-2/neu蛋白过表达组的总生存率低于非过表达组,差异有统计学意义(χ~2=6.258,P=0.017),而两组的无瘤生存率差异无统计学意义(χ~2=0.258,P=0.605);Cox模型多因素分析显示HER-2/neu基因过表达是影响患者总生存率的有意义的预后因素之一.结论 HER-2/neu基因过表达与食管鳞癌的浸润转移及预后密切相关,HEK-2/neu蛋白过表达检测可作为判断食管鳞癌生物学行为和预测预后的参考指标之一,并为HER-2/neu过表达的病例应用HER-2/neu单克隆抗体进行靶向治疗提供依据.     

Effect of Qi-protecting powder （Huqi San） on expression of c-jun,c-fos and c-myc in diethylnitrosamine-mediated hepatocarcinogenesis

To study the inhibitory effect of Huqi San （Qi- protecting powder） on rat prehepatocarcinoma induced by diethylinitrosamine （DEN） by analyzing the mutational activation of c-fos proto-oncogene and over-expression of c-jun and c-myc oncogenes. METHODS： A Solt-Farber two-step test model of prehepatocarcinoma was induced in rats by DEN and 2-acetylaminofluorene （AAF） to investigate the modifying effects of Huqi San on the expression of c-jun, c-fos and c-myc in DEN-mediated hepatocarcinogenesis. Huqi San was made of eight medicinal herbs containing glycoprival granules, in which each milliliter contains 0.38 g crude drugs. T-glutamy-transpeptidase-isoenzyme （T-GTase） was determined with histochemical methods. Level of 8-hydroxydeoxyguanosine （OHdG） formed in liver and c-jun, c-fos and c-myc proto-oncogenes were detected by immunohistochemical methods. RESULTS： The level of 8-OHdG, a mark of oxidative DNA damage, was significantly decreased in the liver of rats with prehepatocarcinoma induced by DEN who received 8 g/kg body weight or 4 g/kg body weight Huqi San before （1 wk） and after DEN exposure （4 wk）. Huqi San- treated rats showed a significant decrease in number of T-GT positive foci （P 〈 0.001, prevention group： 4.96-0.72 vs 29.46-2.17; large dose therapeutic group： 7.53-0.88 vs 29.46-2.17）. On the other hand, significant changes in expression of c-jun, c-fos and c-myc were found in Huqi San-treated rats. CONCLUSION： Activation of c-jun, c-fos and c-myc plays a crucial role in the pathogenesis of liver cancer.Huqi San can inhibit the over-expression of c-jun, c-fos and c-myc oncogenes and liver preneolastic lesions induced by DEN.     

FHOD1 is upregulated in gastric cancer and promotes the proliferation and invasion of gastric cancer cells

Gastric cancer (GC) is one of the main causes of cancer-associated morbidity and mortality worldwide. The present study aimed to investigate the role of the gene encoding formin homology 2 domain containing 1 (FHOD1) protein in GC development. Data from The Cancer Genome Atlas were firstly analyzed, and immunohistochemistry was conducted on GC tissues. The results demonstrated that FHOD1 expression in GC tissues was significantly increased compared with adjacent non-tumor tissues. Furthermore, the expression level of FHOD1 was negatively associated with the overall survival of patients with GC. For the functional studies, lentivirus-mediated short hairpin RNA against FHOD1 and FHOD1-overexpression vectors were constructed to knockdown and overexpress the expression level of FHOD1 in human GC cell lines, respectively. The results indicated that FHOD1 knockdown inhibited the proliferation, colony formation and migratory and invasive abilities of GC cells. Conversely, overexpression of FHOD1 in GC cells promoted soft-agar colony formation and migratory and invasive abilities. In addition, it was demonstrated that genes of which expression levels were correlated with FHOD1 were enriched in the Gene Ontology term of ‘extracellular matrix (ECM) structural constituent’, suggesting that FHOD1 may serve an important role in the regulation of ECM. In conclusion, the present study demonstrated that FHOD1 may exert an oncogenic role in cultured GC cells and be inversely associated with the overall survival of patients with GC.     

EGFR, HER2, and HER3 Expression in Laryngeal Primary Tumors and Corresponding Metastases

Background There are several substances available to target members of the epidermal growth factor receptor (EGFR) family, both for imaging in nuclear medicine and for various forms of therapy. The level and stability of expression in both primary tumors and corresponding metastases is crucial in the assessment of a receptor as a target in systemic tumor therapy. To date, the expression of EGFR family members has only been determined in primary laryngeal carcinomas, and we have not found published data regarding the receptor status in corresponding metastatic lesions. Methods Expression of EGFR, HER2, and HER3 was investigated immunohistochemically in both lymph node metastases and corresponding primary laryngeal squamous carcinomas (n = 40). Results EGFR overexpression (2+ or 3+) was found in 87.5% (35/40) of the laryngeal primary tumors and 82.5% (33/40) of the corresponding lymph node metastases. There was a good agreement between the primary tumors and the paired metastases regarding EGFR expression. HER2 overexpression was found in only four cases (10.5%) of the studied primary tumors and in all cases the HER2 expression was retained in the paired metastases. Another two metastases gained HER2 status when compared to the corresponding primary tumors. Strong HER3 staining was found in 26.7% of both the primary tumors and the corresponding metastases. Conclusions The high frequency and stability in EGFR expression is encouraging for efforts to use EGFR targeting agents (e.g. Iressa, Tarceva, Erbitux or radiolabeled antibodies) for therapy of laryngeal carcinoma. For a few laryngeal carcinoma patients with HER2 overexpression, anti-HER2 agents could possibly be used.     

A developmental influence of the N-methyl-D-aspartate receptor NR3A subunit on prepulse inhibition of startle.

BACKGROUND: The N-methyl-D-aspartate (NMDA) receptor is composed of various conformations of multiple subunits (including NR1, NR2A-D, and NR3A-B). Peak expression of the NR3A subunit occurs approximately 2-3 weeks postnatal, with low levels in adulthood. In the brain, the NR3A subunit is localized primarily in the amygdala, hippocampus, striatum, and cortex. These regions are involved in the modulation of prepulse inhibition of startle (PPI), an operational measure of sensorimotor gating that is modulated by NMDA receptors. NR3A reduces NMDA current in native neurons expressing NR1 and NR2 subunits and forms glycine receptors when expressed with NR1 in the absence of NR2 in both oocyte and mammalian expression systems. METHODS: To examine the role of NR3A in vivo, NR3A knockout (KO), and overexpressing transgenic mice were generated. Adult NR3A overexpressing mice exhibited normal PPI; PPI in NR3A KO mice was tested repeatedly from weaning through adulthood. RESULTS: Male NR3A KO mice exhibited an increase in PPI at 3 and 4 weeks postnatal, whereas female NR3A KO mice did not differ from their WT counterparts at any age tested. CONCLUSIONS: This sex-specific increase in PPI is consistent with the antagonistic role of the NR3A subunit in NMDA receptor function and with the observation that estrogen modulates NMDA receptor function.     

Functional Genomic mRNA Profiling of a large cancer data base demonstrates mesothelin overexpression in a broad range of tumor types

The membrane bound glycoprotein mesothelin (MSLN) is a highly specific tumor marker, which is currently exploited as target for drugs. There are only limited data available on MSLN expression by human tumors. Therefore we determined overexpression of MSLN across different tumor types with Functional Genomic mRNA (FGM) profiling of a large cancer database. Results were compared with data in articles reporting immunohistochemical (IHC) MSLN tumor expression. FGM profiling is a technique that allows prediction of biologically relevant overexpression of proteins from a robust data set of mRNA microarrays. This technique was used in a database comprising 19,746 tumors to identify for 41 tumor types the percentage of samples with an overexpression of MSLN compared to a normal background. A literature search was performed to compare the FGM profiling data with studies reporting IHC MSLN tumor expression. FGM profiling showed MSLN overexpression in gastrointestinal (12–36%) and gynecological tumors (20–66%), non-small cell lung cancer (21%) and synovial sarcomas (30%). The overexpression found in thyroid cancers (5%) and renal cell cancers (10%) was not yet reported with IHC analyses. We observed that MSLN amplification rate within esophageal cancer depends on the histotype (31% for adenocarcinomas versus 3% for squamous-cell carcinomas). Subset analysis in breast cancer showed MSLN amplification rates of 28% in triple-negative breast cancer (TNBC) and 33% in basal-like breast cancer. Further subtype analysis of TNBCs showed the highest amplification rate (42%) in the basal-like 1 subtype and the lowest amplification rate (9%) in the luminal androgen receptor subtype.