International Journal of Molecular Medicine

Woo , Jong-Min ; Park, So Jung; Kang, Ho Il; Kim, Byoung Guk; Shim, Sun Bo; Jee, Seung Wan; Lee, Su Hae; Sin, Ji Soon; Bae, Chang Joon; Jang, Mee Kyung; Cho, Chunghee Kyung; Hwang, Dae Youn; Kim, Chuel Kyu

doi: 10.3892/ijmm_00000390pmid: 20372808

Tau is a neuronal phosphoprotein responsible for the formation of the neurofibrillary tangles in Alzheimer's disease. To characterize the changes in global gene expression in the brain of transgenic mice that overexpress human Tau23 protein in response to the increase of Tau23 phosphorylation, total RNA extracted from the hippocampus of 12-month-old transgenic and wild-type mice was converted to cDNA, labeled with biotin and hybridized to oligonucleotide microarrays. The microarray results were confirmed by real-time RT-PCR and Western blotting method. It was determined that 43 genes were up-regulated and 8 genes were down-regulated by Tau23 in transgenic mice compared to controls, based on the arbitrary difference in the 2-fold change. Among the up-regulated transcripts, those encoding for transporter and oxidoreductase were dramatically over-represented, followed by those related to regulatory molecule, cytoskeletal protein, signaling molecule, and extracellular matrix protein. Genes encoding for transcription factor, regulatory molecule, miscellaneous function, and chaperone were significantly reduced in the down-regulated group. The major genes in the up-regulated categories included Ecrg4, Folr1, Defb11, Aqp1 and Soctdc1. The major genes in the down-regulated categories were Ncor1, Gpm6a, and Hspd1. These results indicate that the microarray analysis identifies several gene functional groups and individual genes that respond to a sustained increase in Tau23 phosphorylation levels in the brain of transgenic mice. In addition, the results suggest the microarray test is a useful tool for increased understanding of the role of Tau23 protein in regulating neurodegenerative disorders.

Lee, Tzung-Yan ; Chang, Hen-Hong

doi: 10.3892/ijmm_00000391pmid: 20372809

Longdan Xiegan Tang (LXT) is a Chinese herbal medicine that is prescribed as an anti-inflammatory aid, a hepato-protectant, and an immunostimulant. In this study, we examined the biological effects of LXT administration in MRL/lpr mice. MRL/lpr mice provide a good model of systemic lupus erythematosus (SLE). These mice develop immunological disturbances and dysregulation in Th1 and Th2 cytokine production. Female mice were randomly separated into two groups. The experimental group received LXT (250 mg/kg/day, po) from 19 to 21 weeks of age. Splenic CD3+CD4+, CD3+CD8+, and CD4+CD25+ T cells were increased in the LXT-administered mice compared to MRL/lpr controls, and this was associated with splenomegaly. There was a marked reduction in IFN-γ, TNF-α, anti-dsDNA antibody, and there were reduced IgG immune complex deposits in the glomeruli. LXT also restored kidney glutathione levels, thereby limiting the toxic effects of the inflammatory mediators iNOS and COX-2, which are overproduced in MRL/lpr mice. Two-dimensional gel electrophoresis was used to analyze proteome changes. LXT protected MRL/lpr mice against developing the lupus syndrome through up-regulation of phosphoglycerate kinase 1 and down-regulation of ferritin light chain 1, selenium-binding protein 2, and α-enolase. This study indicates that LXT at this dose and time course of administration was effective in reducing oxidative stress associated with disease progression in MRL/lpr mice. LXT could be useful as adjunctive therapy for reducing distress in SLE.

Huang, Bo ; Gao, Ying ; Tian, Dali ; Zheng, Maogen

doi: 10.3892/ijmm_00000392pmid: N/A

Small cell lung cancer (SCLC) is a highly aggressive lung neoplasm. To study the pathogenesis of SCLC, we investigated roles of ABCE1, a member of the ATP-binding cassette (ABC) superfamily, in the development of small cell lung cancer. RNA interference was used to knock down ABCE1 expression in human small cell lung cancer cell lines (NCI-H446). Then we examined the effects of ABCE1 knockdown in cancer cells, including proliferation, invasiveness, apoptosis, and gene expression. We found that ABCE1 could be efficiently knocked down by siRNA, and the ABCE1 silence inhibited the proliferation, invasiveness of small cell lung cancer cell lines NCI-H446. In conclusion, our results suggest that ABCE1 play an important role in the pathogenesis of human small cell lung cancer cell. ABCE1 may be used as a potential target of gene therapy for small cell lung cancer in future.

Zhang, Yao ; Wu, Xiao-Hou ; Luo, Chun-Li ; Zhang, Jia-Mo ; He, Bai-Cheng ; Chen, Gang

doi: 10.3892/ijmm_00000393pmid: 20372811

Tumor-derived exosomes express tumor antigens, leading to their promising utility as tumor vaccines, but they also can suppress T-cell signaling molecules and reduce cytotoxic effects. We investigated whether interleukin-12 (IL-12)-anchored exosomes (EXO/IL-12) reverse tumor exosome-mediated inhibition of T-cell activation and cytotoxicity was associated with inhibition of JAK3 and p-STAT5. A co-expression plasmid of pBudCE4.1/IL-12A/ IL-12B-GPI was constructed. EXO/IL-12 was identified by transmission electron microscopy and Western blotting, which induced proliferation and cytotoxicity of T-cells and were analyzed by CFSE-based flow cytometry. Expression of JAK2, JAK3 and p-STAT5 was detected by Western blotting. Our results showed that EXO/IL-12 was much more efficient in induction of the proliferation, release of IFN-γ and cytotoxic effect of T lymphocytes than conventional exosomes in vitro. Exosomes inhibited the expression of JAK3 and phosphorylation of STAT5 in high doses in T-cells, but not JAK2, while EXO/IL-12 had much less attenuated reduction of the expression of p-STAT5. The enhanced cytotoxic effects of T lymphocytes might partly depend on EXO/IL-12 reversing the suppressed expression of p-Stat5 by Jak2/Stat5 pathway. These findings might provide an alternative approach for developing exosomes into tumor vaccines.

Kuhne, Maren ; John, Thilo ; El-Sayed, Karym ; Marzahn, Ulrike ; Aue, Annekatrin ; Kohl, Benjamin ; Stoelzel, Katharina ; Ertel, Wolfgang ; Blottner, Dieter ; Haisch, Andreas ; Schulze-Tanzil, Gundula

doi:

Liu, XiaoLi ; Furuya, Tomoko ; Li, DongYan ; Xu, JingDa ; Cao, XiXi ; Li, QingQuan ; Xu, JiaWen ; Xu, ZuDe ; Sasaki, Kohsuke ; Liu, XiuPing

doi: 10.3892/ijmm_00000395pmid: 20372813

Connexin 26 (Cx26), one of the gap junction-forming family members, is more controversial than other members, as a tumor suppressor. Here, we assessed Cx26 expression in gastric carcinoma, which has not been investigated before, and its clinical significance including survival analyses. Cx26 expression was assessed in 205 tissue samples from gastric carcinoma by immunohistochemistry. Of 205 gastric carcinoma cases, 79 (38.5%) were positive for Cx26 with mainly cytoplasmic localization compared to sporadic membranous staining in normal epithelium, and the expression levels were confirmed by Western blotting and real-time PCR. Negative associations were revealed between Cx26 expression and most clinicopathologic features (all P<0.05). Notably, high Cx26 expression was associated with histological intestinal-type (P=0.017) and early stage of gastric carcinoma. The multivariate regression analysis revealed that positive Cx26 expression was an independent prognostic predictor of intestinal-type GC (P=0.023, HR=2.019). Our findings suggest that aberrant expression of Cx26 in cytoplasm plays a tumor-suppressor role in gastric carcinoma and is an independent biomarker for favorable prognosis in intestinal-type gastric carcinoma.

Nishinakagawa, Takuya ; Fujii, Sho ; Nozaki, Tetsuya ; Maeda, Tatsuhiro ; Machida, Kazuyuki ; Enjoji, Munechika ; Nakashima, Manabu

doi: 10.3892/ijmm_00000396pmid: 20372814

A tumor-associated antigen RCAS1 (receptor binding cancer antigen expressed on SiSo cells) induces cell cycle arrest and apoptosis to a putative RCAS1 receptor (RCAS1-R) expressing cells such as T, B, and natural killer cells. Its expression is related with clinical poor prognosis of some malignant tumors. It is suggested that the expression of RCAS1 in tumor cells plays an important role in evasion from host immune system resulting tumor progression, invasion and metastasis. However, the mechanism of RCAS1 induced cell cycle arrest and apoptosis has not been clarified. In this study, we established a mouse L cell line transformed with tetracycline-induced rcas1 gene expression system and analyzed the RCAS1 functions. We showed that RCAS1 induced cytochrome c release and activation of caspase-3 for apoptosis. Moreover, we investigated cell cycle associated proteins and revealed that cyclin D3 decreased significantly and no change was seen in the expression levels of the other proteins. These results suggest that cyclin D3 is one of the key target molecules in the RCAS1-RCAS1-R signaling pathway.

Chai, Linlin ; Cao, Chuan ; Bi, Sheng ; Dai, Xia ; Gan, Lu ; Guo, Rui ; Li, Shirong

doi: 10.3892/ijmm_00000397pmid: 20372815

Epidermal stem cells (ESCs) are essential not only for tissue homeostasis but also for skin to respond to insults, but the mechanisms of stem cell regulation are unknown. To investigate the function of Rac1 in ESC development, we introduced either the dominant negative isoform or constitutively the active mutant of Rac1 in cultured human ESCs by using a retroviral vector and then analyzed the consequences. Upon activation, Rac1 increased surface α6/β1 integrin levels and promoted colony forming efficiency of ESCs. Conversely, dominant negative Rac1 caused a progressive reduction in growth rate, an inhibition of adhesiveness and a marked stimulation of terminal differentiation, without any effect on the cell cycle. These results were consistent with the role of Rac1 in determining the fate of ESCs by controlling their exit from the stem cell compartment. Our results reveal a novel biological role for Rac1 and provide new insights into the mechanism regulating ESCs.

Zhang, Yihua ; Luo, Zhidan ; Ma, Liqun ; Xu, Qiang ; Yang, Qihong ; Si, Liangyi

doi: 10.3892/ijmm_00000398pmid: 20372816

Advanced glycosylation end products (AGE) and its receptor (RAGE) axis is involved in the regulation of lipid homeostasis and is critical in the pathogenesis of diabetic atherosclerosis. We investigated the protective role of resveratrol against the AGE-induced impairment on macrophage lipid homeostasis. In THP-1-derived macrophages, RAGE was dose-dependently induced by AGE and played a key role in the AGE-induced cholesterol accumulation. Resveratrol markedly reduced RAGE expression via peroxisome proliferator-activated receptor (PPAR) γ but not PPARα or AMP-activated protein kinase. Importantly, pretreatment with resveratrol significantly ameliorated AGE-induced up-regulation of scavenger receptor-A (SR-A) and down-regulation of ATP-binding cassette (ABC) A1 and ABCG1 and thus effectively prevented the cholesterol accumulation in macrophages as shown by cellular cholesterol analysis and oil red O staining. Moreover, blockade of PPARγ abolished all these effects of resveratrol. Collectively, our results indicate that resveratrol prevents the impairment of AGE on macrophage lipid homeostasis partially by suppressing RAGE via PPARγ activation, which might provide new insight into the protective role of resveratrol against diabetic atherosclerosis.

Khoshnoud, Reza ; He, Qimin ; Sylván, Maria ; Khoshnoud, Aida ; Ivarsson, Madleen ; Fornander, Tommy ; Bergh, Jonas ; Frisell, Jan ; Rutqvist, Lars-Erik ; Skog, Sven

doi: 10.3892/ijmm_00000399pmid: