Potent inhibition of SARS-associated coronavirus (SCOV) infection and replication by type I interferons (IFN-alpha/beta) but not by type II interferon (IFN-gamma).

We sought to investigate the anti-severe acute respiratory syndrome (SARS)-associated coronavirus (SCoV) activities of type I (alpha and beta) and type II (gamma) interferons (IFN) in vitro. Type I IFNs protected cells from cytopathic effects (CPE) induced by SCoV, and inhibited viral genomic RNA replication in FRhk-4 cells (measured by quantitative RT-PCR) in a dose-dependent manner. Intracellular viral RNA copies were reduced 50% by IFN-alpha at a concentration of 25 U/ml and by IFN-beta at a concentration of 14 U/ml. IFN-gamma had fewer effects on inhibition of viral infection and replication. The type I IFN receptor signaling pathway in host cells is mainly involved in the inhibition of SCoV infection and replication. Type I IFNs could be used as potential agents for anti-SARS treatment.     

Distinct patterns of ALDH1A1 expression predict metastasis and poor outcome of colorectal carcinoma

Purpose: Aldehyde dehydrogenase 1A1 (ALDH1A1) has been proposed as a candidate biomarker for colorectal carcinoma (CRC). However, the heterogeneity of its expression makes it difficult to predict the outcome of CRC. The aim of this study was to evaluate the diagnostic and prognostic value of this molecule in CRC. Methods and Results: In this study, we examined ALDH1A1 expression by immunohistochemistry including 406 cases of primary CRC with corresponding adjacent mucosa, with confirmation of real-time PCR and Western blotting. We found that the expression patterns of ALDH1A1 were heterogeneous in the CRC and corresponding adjacent tissues. We defined the ratio of ALDH1A1 level in adjacent mucosa to that in tumor tissues as R_A/C and found that the capabilities of tumor invasion and metastasis in the tumors with R_A/C < 1 were significantly higher than those with R_A/C ≥ 1. Follow-up data showed the worse prognoses in the CRC patients with R_A/C < 1. For understanding the underlying mechanism, the localization of β-catenin was detected in the CRC tissues with different patterns of ALDH1A1 expression from 221 patients and β-catenin was found preferentially expressed in cell nuclei of the tumors with R_A/C < 1 and ALDH1A1^high expression of HT29 cell line, indicating that nuclear translocation of β-catenin might contribute to the increased potentials of invasion and metastasis. Conclusion: Our results indicate that R_A/C is a novel biomarker to reflect the distinct expression patterns of ALDH1A1 for predicting metastasis and prognosis of CRC.     

Suppression of in vivo tumor growth and induction of suspension cell death by tissue inhibitor of metalloproteinases (TIMP)-3

Tissue inhibitor of metalloproteinases-3(TEMP-3), a novel memberof TEMP family genes, has been recently cloned and shown tobe expressed in preneoplastic but not in neoplastic mouse JB6epidermal cells (Sun et al. 1994 Cancer Res., 54, 11139). Thisdown regulation of the gene appears to be attributable at leastin part to alteration of gene methylation (Sun et al. 1995 J.Biol Chem., 270, 19312). Little is known, however, about therole of TEMP-3 in human cancers. We screened several human tumorcell lines for TEMP-3 expression and found that a colon carcinomaline, DLD-1, did not express TEMP-3. If down regulation of TIMP-3is causally related to carcino-genesis, re-expression by transfectionmay reverse the tumor cell phenotype. We therefore overexpressedhuman TEMP-3 in DLD-1 cells. TEMP-3 transfectants showed a serum-dependentgrowth inhibition in monolayer culture and a decreased growthpotential in nude mice in a manner dependent on the level ofTEMP-3 expression. A transfectant expressing a high level ofactive hTEMP-3 completely lost the ability to form tumors followings.c. injection into nude mice. We also tested TEMP-3 expressingcells and neocontrol TEMP-3 negative cells for their abilityto grow in liquid suspension culture, since both cells grewin semi-solid soft agar. As compared to neocontrol cells, TIMP-3over-expressors formed large aggregates, followed by cell death.This effect was not mimicked by BB94, a broad MMP inhibitor.We conclude from this study that (i) TEMP-3 overexpression inhuman colon carcinoma cells induces growth arrest in low serumconditions and inhibits in vivo tumor growth and (ii) the TEMP-3-inducedlarge aggregate formation and subsequent cell death under suspensiongrowth cannot be explained by its MMP inhibitory activity.     

Aldehyde dehydrogenase 1A1 circumscribes high invasive glioma cells and predicts poor prognosis

Glioma is the most aggressive brain tumor with high invasiveness and poor prognosis. More reliable, sensitive and practical biomarkers to reveal glioma high invasiveness remain to be explored for the guidance of therapy. We herein evaluated the diagnostic and prognostic value of aldehyde dehydrogenase 1A1 (ALDH1A1) in the glioma specimens from 237 patients, and found that ADLH1A1 was frequently overexpressed in the high-grade glioma (WHO grade III-IV) as compared to the low-grade glioma (WHO grade I-II) patients. The tumor cells with ALDH1A1 expression were more abundant in the region between tumor and the borderline of adjacent tissue as compared to the central part of the tumor. ALDH1A1 overexpression was associated with poor differentiation and dismal prognosis. Notably, the overall and disease-free survivals of the patients who had ALDH1A1⁺ tumor cells sparsely located in the adjacent tissue were much worse. Furthermore, ALDH1A1 expression was correlated with the “classical-like” (CL) subtype as we examined GBM specimens from 72 patients. Multivariate Cox regression analysis revealed that ALDH1A1 was an independent marker for glioma patients’ outcome. Mechanistically, both in vitro and in vivo studies revealed that ALDH1A1⁺ cells isolated from either a glioblastoma cell line U251 or primary glioblastoma cells displayed significant invasiveness, clonogenicity, and proliferation as compared to ALDH1A1^- cells, due to increased levels of mRNA and protein for matrix metalloproteinase 2, 7 and 9 (MMP2, MMP7 and MMP9). These results indicate that ALDH1A1⁺ cells contribute to the progression of glioma including invasion, proliferation and poor prognosis, and suggest that targeting ALDH1A1 may have important implications for the treatment of highly invasive glioma.     

Tumor necrosis factor-α-induced protein 1 and immunity to hepatitis B virus

AIM: To compare the gene expression profile in a pair of HBV-infected twins. METHODS: The gene expression profile was compared in a pair of HBV-infected twins. RESULTS: The twins displayed different disease outcomes. One acquired natural immunity against HBV, whereas the other became a chronic HBV carrier. Eighty-eight and forty-six genes were found to be up- or down-regulated in their PBMCs, respectively. Tumor necrosis factor-alpha-induced protein 1 (TNF-alphaIP1) that expressed at a higher level in the HBV-immune twins was identified and four pairs of siblings with HBV immunity by RT-PCR. However, upon HBV core antigen stimulation, TNF-alphaIP1 was downregulated in PBMCs from subjects with immunity, whereas it was slightly upregulated in HBV carriers. Bioinformatics analysis revealed a K+ channel tetramerization domain in TNF-alphaIP1 that shares a significant homology with some human, mouse, and C elegan proteins. CONCLUSION: TNF-alphaIP1 may play a role in the innate immunity against HBV.     

Behavioral and biochemical studies of total furocoumarins from seeds of Psoralea corylifolia in the forced swimming test in mice

The behavioral and biochemical effects of total furocoumarins from seeds of Psoralea corylifolia (TFPC) were investigated in the forced swimming test (FST) in mice in comparison with amitriptyline and fluoxetine. TFPC was found to reduce the duration of immobility in the FST without accompanying changes in ambulatory, rearing and grooming behaviors in the open-field test. After a 3-day treatment, TFPC at the doses from 7.5 to 100 mg/kg significantly decreased the immobility time. The efficacy of the higher doses exceeded that of amitriptyline at 10 and 20 mg/kg and fluoxetine at 13 mg/kg. After a 7- or 14-day treatment, TFPC exhibited an inverted U-shaped dose-response relations, maximal effects were obtained at 30 mg/kg, when the efficacy appeared to be more than that of amitriptyline and fluoxetine. In animal brain and liver, after 14-day treatment, TFPC significantly inhibited monoamine oxidase A and B (MAO-A and MAO-B) activities with an inverted U-shaped dose-dependent relationship in brain, and with dose-dependent relationship in liver. Moreover, TFPC was more potent for MAO-B than MAO-A, except at the lowest dose, which was similar to amitriptyline and fluoxetine. In addition, TFPC blocked plasma elevated cortisol level, an indicator of the hypothalamic-pituitary-adrenal (HPA) axis. TFPC significantly decreased liver superoxide dismutase (SOD) activity and malondialdehyde (MDA) level, two indicators of oxidative stress, providing an inverted U-shaped dose-dependent relationship. These results suggest that TEPC possesses potent antidepressant properties that are mediated via MAO activity, HPA axis action and oxidative stress in the FST in mice.     

Antidepressant-like effects of psoralen isolated from the seeds of Psoralea corylifolia in the mouse forced swimming test

The forced swimming test (FST) is suggested to produce abnormalities in the serotonergic and hypothalamic-pituitary-adrenal (HPA) axis systems. Therefore, compounds that attenuate these neurobiological alterations may have potential as antidepressants. The behavioral and biochemical effects of psoralen, a major furocoumarin isolated from Psoralea corylifolia, were investigated in the FST model of depression in male mice. Psoralen significantly reduced immobility and increased swimming without altering climbing in the mouse FST. Psoralen remarkably reversed FST-induced alterations in serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) levels in frontal cortex and hippocampus in mice. Furthermore, psoralen attenuated FST-induced elevations in serum corticotropin-releasing factor (CRF) and corticosterone concentrations to normalize the HPA axis activity. These results suggested that psoralen possessed potent antidepressant-like properties which were at least in part mediated by improving the abnormalities in the serotonergic and the HPA axis systems.     

Pluronic L-81 ameliorates diabetic symptoms in db/db mice through transcriptional regulation of microsomal triglyceride transfer protein

AIM： To test whether oral L-81 treatment could improve the condition of mice with diabetes and to investigate how L-81 regulates microsomal triglyceride transfer protein （MTP） activity in the liver.
METHODS： Genetically diabetic （db/db） mice were fed on chow supplemented with or without L-81 for 4 wk. The body weight, plasma glucose level, plasma lipid profile, and adipocyte volume of the db/db mice were assessed after treatment. Toxicity of L-81 was also evaluated. To understand the molecular mechanism, HepG2 cells were treated with L-81 and the effects on apolipoprotein B （apoB） secretion and mRNA level of the MTP gene were assessed.
RESULTS： Treatment of db/db mice with L-81 significantly reduced and nearly normalized their body weight, hyperphagia and polydipsia. L-81 also markedly decreased the fasting plasma glucose level, improved glucose tolerance, and attenuated the elevated levels of plasma cholesterol and triglyceride. At the effective dosage, little toxicity was observed. Treatment of HepG2 cells with L-81 not only inhibited apoB secretion, but also significantly decreased the mRNA level of the MTP gene. Similar to the action of insulin, L-81 exerted its effect on the MTP promoter.
CONCLUSION： L-81 represents a promising candidate in the development of a selective insulin-mimetic molecule and an anti-diabetic agent.