Increased free prostate specific antigen serum levels in Alzheimer's disease, correlation with Cognitive Decline.

BACKGROUND/AIMS: Prostate specific antigen (PSA) is regulated by steroid hormones, such as testosterone, the serum levels of which are altered in patients with Alzheimer's disease (AD).This pilot study compared serum levels of the free (f) PSA between AD, mild cognitive impairment (MCI), and control subjects, and evaluated the relationship between fPSA serum levels and cognitive assessment tests and neuroimaging data. In addition, in a subgroup of AD patients, we correlated fPSA serum levels with the existing data on serum levels of amyloid-beta (Aß), and iron-related proteins, including hepcidin and ferritin. METHODS: Frozen serum samples from the Oregon Tissue Bank were used to measure serum levels of fPSA using enzyme-linked immunosorbent assay. RESULTS: fPSA serum levels calculated as median ±â€¯SD were higher in AD males (663.6 ±â€¯821.0 pg/ml) compared to control males (152.0 ±â€¯207.0 pg/ml), p = 0.003. A similar Pattern emerged when comparing MCI males (310.7 ±â€¯367.0 pg/ml) to control males (P = 0.02). Correlation studies showed a significant association between fPSA and CDR (r = 0.56, P = 0.006) and CDR-SOB (r = 0.54, P = 0.009) in AD males. CONCLUSION: Additional studies in a larger cohort are required for determining whether fPSA can be used as biomarker of AD disease progression and whether it has the potential to identify male subjects at risk of AD dementia.

Fingolimod anti-inflammatory and neuroprotective effects modulation of RAGE axis in multiple sclerosis patients.

BACKGROUND: We investigated Fingolimod treatment effects on the RAGE (receptor for advanced glycation endproducts) axis in multiple sclerosis (MS) patients. The primary outcome of the study was whether Fingolimod treatment increases serum levels of the soluble RAGE isoforms, sRAGE and esRAGE - both being considered putative endogenous inhibitors of RAGE signaling. Additional variables were serum levels of RAGE ligands, the high mobility group box (HMGB)1 and pentosidine. METHODS: Serum levels of the study variables were measured by ELISA, and compared between baseline (before Fingolimod treatment) and 6 and 12 months post-drug treatment in 17 relapsing MS patients. Fingolimod treatment effects on MS disease progression were assessed by comparing pre- and post-Fingolimod values of the EDSS and rate of clinical relapse, and changes in the T1-and T2-enahncing lesions on the MRI scan.methods RESULTS: Twelve months treatment with Fingolimod increased serum levels of sRAGE and esRAGE by 32.4% (P = 0.004) and 48.5% (P = 0.007) respectively. In addition, Fingolimod treatment reduced serum levels of HMGB1 by 71.6% (P = 0.02) and pentosidine serum levels by 41.3% (P = 0.12). EDSS remained stable (baseline: 3.57 ± 1.56; post-Fingolimod: 3.54 ± 1.2, P = 0.96) and the rate of clinical relapse decreased near significantly (P = 0.094). T1-and T2-enhancing lesions remained stable, showing no significant changes pre-vs. post-Fingolimod treatment. CONCLUSION: Fingolimod mediates modulation of the RAGE axis which apparently contributes to the Fingolimod's anti-inflammatory and neuroprotective effects. These findings may provide a rationale for the clinical efficacy of Fingolimod in pathological states other than MS, where dysregulation of the RAGE axis plays a role.

Nanotherapy silencing the interleukin-8 gene produces regression of prostate cancer by inhibition of angiogenesis.

Interleukin-8 (IL-8) is a pro-angiogenic cytokine associated with aggressive prostate cancer (CaP). We detected high levels of IL-8 in sera from patients with CaP compared with healthy controls and patients with benign prostatic hypertrophy. This study examines the role of IL-8 in the pathogenesis of metastatic prostate cancer. We developed a biocompatible, cationic polylactide (CPLA) nanocarrier to complex with and efficiently deliver IL-8 small interfering RNA (siRNA) to CaP cells in vitro and in vivo. CPLA IL-8 siRNA nanocomplexes (nanoplexes) protect siRNA from rapid degradation, are non-toxic, have a prolonged lifetime in circulation, and their net positive charge facilitates penetration of cell membranes and subsequent intracellular trafficking. Administration of CPLA IL-8 siRNA nanoplexes to immunodeficient mice bearing human CaP tumours produced significant antitumour activities with no adverse effects. Systemic (intravenous) or local intra-tumour administration of IL-8 siRNA nanoplexes resulted in significant inhibition of CaP growth. Magnetic resonance imaging and ultrasonography of experimental animals demonstrated reduction of tumour perfusion in vivo following nanoplex treatment. Staining of tumour sections for CD31 confirmed significant damage to tumour neovasculature after nanoplex therapy. These studies demonstrate the efficacy of IL-8 siRNA nanotherapy for advanced, treatment-resistant human CaP.

Reduced expression of membrane-bound (m)RAGE is a biomarker of multiple sclerosis disease progression.

OBJECTIVES: This study is one in series measuring RAGE axis (receptor for advanced glycation end products, its isoforms, and ligands) as a biomarker in multiple sclerosis (MS). We identified and quantified membrane-bound RAGE (mRAGE) expression levels on freshly isolated PBMCs and its subpopulation (monocytes and T cells), and determined the relationship between mRAGE expression levels and MS disease severity. MATERIALS AND METHODS: mRAGE expression was determined for 28 MS patients and 16HCs, by flow cytometry, using fluorochrome unconjugated primary RAGE monoclonal antibody and a polyclonal secondary antibody conjugated to R-Phycoerythrin (PE). RESULTS: After adjusting for multiple comparisons and correcting for group differences in age and gender, MS patients showed higher percentages of mRAGE-positive on PBMCs (12.4±2.1 vs. 4.08±0.8, P=0.02), monocytes (37.4±5.8 vs. 20.1±5.0, P=0.08) and T cells (4.1±1.2 vs. 2.1±0.3, P=0.05). SPMS patients' showed lower percentages of RAGE-positive monocytes (13.7±5.5 vs. 49.5±6.6, P=0.0006) and RAGE-positive T cells (4.1±1.8 vs. 6.6±1.5, P=0.04) than RRMS patients. We observed a negative relationship between the percentages of mRAGE-positive PBMCs and MS severity scale (MSSS) (r=-0.39, P=0.04), monocytes and EDSS (r=-0.48, P=0.01), monocytes and MSSS (r=-0.58, P=0.001), and T cells and MSSS (r=-0.40, P=0.04). Monocytes expression of mRAGE showed 0.811 area under the curve (95% CI: 0.64-0.98) sensitivity/specificity for MSSS. CONCLUSION: The reduced mRAGE expression on PBMCs in general, and on monocytes in particular, can be used as biomarker of MS disease severity and progression.

High-mobility group box 1 in multiple sclerosis.

This study is one in series determining the potential of RAGE axis (receptor for advanced glycation end products, isoforms, ligands) as a biomarker in multiple sclerosis (MS). We evaluated serum levels of RAGE ligand, the high-mobility group box (HMGB)1 in MS patients, and assessed the correlation between HMGB1 serum levels and the use of disease-modifying drugs (DMDs), and between HMGB1 serum levels and indicators of MS disease severity. HMGB1 serum levels were compared between 96 (23 males) MS patients and 34 age- and gender-matched healthy controls (HCs) using enzyme-linked immunosorbent assays. DMD-naïve MS patients had significantly higher HMGB1 serum levels compared with DMD-treated (P = 0.04) and compared with HCs (P = 0.01). HMGB1 serum levels were not significantly different between total MS patients (DMD-naïve plus DMD-treated) and HCs (P = 0.09). DMD-naïve MS patients in clinical relapse tended to have lower HMGB1 serum levels than clinically stable RRMS patients (P = 0.07). HMGB1 serum levels showed 0.65 area under the curve (95 % CI 0.55-0.95) sensitivity/specificity for MS clinical relapse. The role of HMGB1 in MS disease pathology and DMD modulation of this protein warrant further investigations.

Anti-angiogenic activity of PSA-derived peptides.

BACKGROUND: PSA is a biomarker for diagnosis and management of prostate cancer. PSA is known to have anti-tumorigenic activities, however, the physiological role of PSA in prostate tumor progression is not well understood. METHODS: Five candidate peptides identified based upon computer modeling of the PSA crystal structure and hydrophobicity were synthesized at >95% purity. The peptides in a linear form, and a constrained form forced by a di-sulfide bond joining the two ends of the peptide, were investigated for anti-angiogenic activity in HUVEC. RESULTS: None of the five PSA-mimetic peptides exhibited PSA-like serine protease activity. Two of the peptides demonstrated significant anti-angiogenic activity in HUVEC based on (i) inhibition of cell migration and invasion; (ii) inhibition of tube formation in Matrigel; (iii) anti-angiogenic activity in a sprouting assay; and (iv) altered expression of pro- and anti-angiogenic growth factors. Constrained PSA-mimetic peptides had greater anti-angiogenic activity than the corresponding linearized form. Complexing of PSA with ACT eliminated PSA enzymatic activity and reduced anti-angiogenic activity. In contrast, ACT had no effect on the anti-angiogenic effects of the linear or constrained PSA-mimetic peptides. Modeling of the ACT-PSA complex demonstrated ACT sterically blocks the anti-angiogenic activity of the two bioactive peptides. CONCLUSIONS: The interaction of a hydrophilic domain on the surface of the PSA molecule with a target on the cell membrane of prostate endothelial and epithelial cells was responsible for the anti-angiogenic or anti-tumorigenic activity of PSA: enzymatic activity was not associated with anti-angiogenic effects. Furthermore, since PSA and ACT are both expressed within the human prostate tissue microenvironment, the balance of their expression may represent a mechanism for endogenous regulation of tissue angiogenesis.

New serum biomarkers for prostate cancer diagnosis.

BACKGROUND: Prostate-specific antigen (PSA) is currently used as a biomarker for diagnosis and management of prostate cancer (CaP). However, PSA typically lacks the sensitivity and specificity desired of a diagnostic marker. OBJECTIVE: The goal of this study was to identify an additional biomarker or a panel of biomarkers that is more sensitive and specific than PSA in differentiating benign versus malignant prostate disease and/or localized CaP versus metastatic CaP. METHODS: Concurrent measurements of circulating interleukin-8 (IL-8), Tumor necrosis factor-α (TNF-α) and soluble tumor necrosis factor-α receptors 1 (sTNFR1) were obtained from four groups of men: (1) Controls (2) with elevated prostate-specific antigen with a negative prostate biopsy (elPSA_negBx) (3) with clinically localized CaP and (4) with castration resistant prostate cancer. RESULTS: TNF-α Area under the receiver operating characteristic curve (AUC = 0.93) and sTNFR1 (AUC = 0.97) were strong predictors of elPSA_negBx (vs. CaP). The best predictor of elPSA_negBx vs CaP was sTNFR1 and IL-8 combined (AUC = 0.997). The strongest single predictors of localized versus metastatic CaP were TNF-α (AUC = 0.992) and PSA (AUC = 0.963) levels. CONCLUSIONS: The specificity and sensitivity of a PSA-based CaP diagnosis can be significantly enhanced by concurrent serum measurements of IL-8, TNF-α and sTNFR1. In view of the concerns about the ability of PSA to distinguish clinically relevant CaP from indolent disease, assessment of these biomarkers in the larger cohort is warranted.

The prevalence of the classical and non-classical cardiovascular risk factors in multiple sclerosis patients.

BACKGROUND: Inflammation is known to play a role in cererovascular risk. Multiple sclerosis (MS) is a neurodegenerative disease that is initially characterized by inflammatory changes in the brain. We hypothesized that due to chronic inflammation, MS patients would present with a higher levels of cardiovascular (CV) risk factors than non-MS patients. METHODS: We performed a retrospective chart review on 206 MS patients and 142 control patients suffering from meningiomas and acoustic neuromas, non inflammatory, non autoimmune diseases of the brain. The obtained data included fasting lipid profiles, plasma glucose, systolic and diastolic blood pressure (BP), serum levels of homocysteine and uric acid, data on iron status, smoking habit, and list of medications. In addition, data on indicators of MS disease severity was obtained for MS patients. RESULTS: MS patients had significantly higher total plasma cholesterol, p = 0.01, and plasma high density lipoprotein, P < 0.001, but lower plasma glucose, P < 0.001, and systolic BP, P = 0.001, than non-MS patients. In addition, MS patients had lower erythrocyte sedimentation rate and serum vitamin B12, but higher serum folic acid and vitamin D3 than non-MS patients. A positive correlation was observed between plasma glucose and the extended disability status scale (EDSS), P = 0.008, and between plasma glucose and the rate of clinical relapse, P = 0.001. CONCLUSION: The MS pathophysiology may be among factors for the lower CV risk factors in MS patients. Future studies should examine whether the chronic use of many pharmacological agents influence CV risk factors in MS patients.

Overexpression of MMP-9 contributes to invasiveness of prostate cancer cell line LNCaP.

Matrix metallaprotinase-9 (MMP-9) is zinc-containing proteinase whose expression and trafficking are frequently altered in cancer. MMP-9 in the plasma membrane and the secreted forms are thought to contribute to the invasive and metastatic properties of malignant tumors. We have manipulated the expression of MMP-9 in prostate tumor cell line LNCaP and measured their capacity to invade through a basement membrane matrix. Stable expression of human MMP-9 in a poorly metastatic LNCaP prostate cancer cell line produced a 2-3-fold increase in MMP-9 activity and a comparable increase in invasiveness. Transient transfection of LNCaP stable clone expressing MMP-9 with MMP-9 antisense oligonucleotide (ASODN) produced 55-90% less MMP-9 than control cells and were proportionately less invasive. In contrast, manipulating MMP-9 levels had no effect on cell migration across an uncoated membrane. A standard MMP-9 inhibitor at a concentration ranging from 1-10 nM, caused a nearly quantitative inhibition of extracellular MMP-9 activity and had significant effect on basement membrane invasion. Collectively, these results confirm the role of MMP-9 in tissue remodeling associated with prostate tumor invasion.

Enzymatic activity of free-prostate-specific antigen (f-PSA) is not required for some of its physiological activities.

BACKGROUND: Prostate specific antigen (PSA) is a well known biomarker for early diagnosis and management of prostate cancer. Furthermore, PSA has been documented to have anti-angiogenic and anti-tumorigenic activities in both in vitro and in vivo studies. However, little is known about the molecular mechanism(s) involved in regulation of these processes, in particular the role of the serine-protease enzymatic activity of PSA. METHODS: Enzymatic activity of PSA isolated directly from seminal plasma was inhibited specifically (>95%) by incubation with zinc2+ . Human umbilical vein endothelial cells (HUVEC) were utilized to compare/contrast the physiological effects of enzymatically active versus inactive PSA. RESULTS: Equimolar concentrations of enzymatically active PSA and PSA enzymatically inactivated by incubation with Zn2+ had similar physiological effects on HUVEC, including inhibiting the gene expression of pro-angiogenic growth factors, like VEGF and bFGF, and up-regulation of expression of the anti-angiogenic growth factor IFN-γ; suppression of mRNA expression for markers of blood vessel development, like FAK, FLT, KDR, TWIST-1; P-38; inhibition of endothelial tube formation in the in vitro Matrigel Tube Formation Assay; and inhibition of endothelial cell invasion and migration properties. DISCUSSION: Our data provides compelling evidence that the transcriptional regulatory and the anti-angiogenic activities of human PSA are independent of the innate enzymatic activity.

Plasma pentosidine: a potential biomarker in the management of multiple sclerosis.

BACKGROUND: The chronic inflammation associated with multiple sclerosis (MS) may lead to the upregulation of pentosidine. OBJECTIVES: This cross-sectional study compares plasma pentosidine levels among healthy controls (HCs) and patients with MS at different disease stages. The study also determines pentosidine's usefulness as a biomarker of MS disease activity and/or severity via its correlation with a number of indicators of MS disease. METHODS: Pentosidine levels were analyzed in 98 MS patients and 43 HCs using reverse-phase high-pressure liquid chromatography with fluorescence detection. RESULTS: Plasma pentosidine levels were significantly higher in MS patients when compared with HCs (p = 0.02). Patients on disease-modifying therapies (DMTs) had lower plasma pentosidine levels when compared with DMT-naïve patients (p = 0.01). Pentosidine plasma levels correlated with indicators of MS disease severity, including Extended Disability Status Scale (p = 0.03), MS Severity Scale (p = 0.01), and MS Functional Composite (p = 0.03). No correlation between pentosidine levels and age, rate of clinical relapse, and disease duration was observed. CONCLUSIONS: Our results suggest that pentosidine could be a novel, inflammatory biomarker in MS clinical practice. Longitudinal studies are warranted to determine any causal relationship between changes in plasma pentosidine levels and MS disease pathology. These studies may pave the way for use of advanced glycation end product (AGE) inhibitors and AGE-breaking agents as new therapeutic modalities in MS.

Immunomodulatory responses of peripheral blood mononuclear cells from multiple sclerosis patients upon in vitro incubation with the flavonoid luteolin: additive effects of IFN-beta.

The study is aimed to determine the role of luteolin (3',4',5,7-tetrahydroxyflavone), alone and in combination with human interferon-beta (IFN-beta), in modulating the immune response(s) of peripheral blood mononuclear cells (PBMCs) isolated from multiple sclerosis (MS) patients. PBMC proliferation in the presence or absence of these drugs was determined and the production of pro-inflammatory cytokines (IL-1beta, TNF-alpha), and the ratio of cell migration mediator MMP-9, and its inhibitor, TIMP-1 was assessed in the culture supernatants. Luteolin reduced, in a dose-dependent manner, the proliferation of PBMCs, and modulated the levels of IL-1beta and TNF-alpha released by PBMCs in the culture supernatants. Luteolin reduced the MMP-9/TIMP-1 ratio via lowering MMP-9 production. In the majority of cases, luteolin, when combined with IFN-beta, had additive effects in modulating cell proliferation, IL-1beta, TNF-alpha, MMP-9 and TIMP-1.

Regulation of PSA secretion and survival signaling by calcium-independent phopholipase A(2)beta in prostate cancer cells.

BACKGROUND: Serum prostate specific antigen (PSA) levels in prostate cancer patients serve as a useful biomarker for diagnosing and monitoring prostate cancer. Recently, secreted PSA has been characterized as an autocrine survival factor through activation of Akt and induction of AR. In the normal prostate, PSA is secreted in the lumen of prostatic ducts to lyse proteins in the seminal coagulum. METHODS: However, the mechanism for constitutive PSA secretion from benign prostate and its transport across the prostate-blood barrier into serum are unknown. Regulation of peptide secretion by iPLA(2)-beta has been reported in non-prostatic tissue and in prostate tissue iPLA(2)-beta is reported to be under androgen regulation. We investigated whether iPLA(2) plays a role for in PSA secretion by comparing iPLA(2) activity and expression in normal prostate epithelial RWPE-1 cells and in LNCaP prostate cancer cells. Expression of the two active iPLA(2)-beta mRNA splice variants, LH-iPLA(2) and SH-iPLA(2), were increased and the inhibitory ankyrin-iPLA(2) isoform was markedly reduced in LNCaP cells as compared to normal prostate epithelial RWPE-1 cells. RESULTS: These changes are consistent with a higher enzymatic activity in LNCaP cells. The iPLA(2)-beta-specific inhibitor BEL inhibited PSA secretion and induced apoptosis in LNCaP cells. iPLA(2) knockdown using SiRNA inhibited PSA secretion, downregulated AR and induced apoptosis. Exogenous PSA suppressed BEL-induced apoptosis and neutralizing anti-PSA antibody blocked the survival effect of PSA. CONCLUSIONS: These data indicate that iPLA(2)-beta participates in regulating PSA secretion and supports the concept that secreted PSA provides an autocrine survival function in LNCaP cells.

Quercetin and interferon-beta modulate immune response(s) in peripheral blood mononuclear cells isolated from multiple sclerosis patients.

The study is aimed to determine the role of quercetin (3,3'4',5,7-pentahydroxy flavone), alone and in combination with human interferon-beta (IFN-beta), in modulating the immune response(s) of peripheral blood mononuclear cells (PBMC) isolated from multiple sclerosis (MS) patients and from normal healthy subjects. PBMC proliferation in the presence or absence of these drugs was determined and the production of proinflammatory cytokines (IL-1beta, TNF-alpha), and the ratio of cell migration mediator MMP-9, and its inhibitor, TIMP-1 were assessed in the culture supernatants. Quercetin reduced, in a dose-dependent manner, the proliferation of PBMC and modulated the level of IL-1beta and TNF-alpha released by PBMC in the culture supernatants. Quercetin reduced the MMP-9/TIMP-1 ratio via lowering MMP-9 production. Quercetin, when combined with IFN-beta, had additive effects in modulating TNF-alpha and MMP-9. These immunomodulatory responses to quercetin were similar between MS patients and healthy control (HC) subjects.

The dietary bioflavonoid, quercetin, selectively induces apoptosis of prostate cancer cells by down-regulating the expression of heat shock protein 90.

BACKGROUND: Human and animal studies have suggested that diet-derived flavonoids, in particular quercetin may play a beneficial role by preventing or inhibiting oncogenesis, but the underlying mechanism remains unclear. The aim of this study is to evaluate the effect(s) of quercetin on normal and malignant prostate cells and to identify the target(s) of quercetin's action. METHODOLOGY: We addressed this question using cells in culture and investigated whether quercetin affects key biological processes responsible for tumor cell properties such as cell proliferation and apoptosis and also studied the effect of quercetin on the proteome of prostate cancer cells using difference gel electrophoresis (DIGE) to assess changes in the expression of relevant proteins. RESULTS: Our findings demonstrate that quercetin treatment of prostate cancer cells results in decreased cell proliferation and viability. Furthermore, we demonstrate that quercetin promotes cancer cell apoptosis by down-regulating the levels of heat shock protein (Hsp) 90. Depletion of Hsp90 by quercetin results in decreased cell viability, levels of surrogate markers of Hsp90 inhibition (intracellular and secreted), induced apoptosis and activation of caspases in cancer cells but not in normal prostate epithelial cells. Knockdown of Hsp90 by short interfering RNA also resulted in induction apoptosis similar to quercetin in cancer cells as indicated by annexin V staining. CONCLUSION: Our results demonstrate that quercetin down-regulates the expression of Hsp90 which, in turn, induces inhibition of growth and cell death in prostate cancer cells while exerting no quantifiable effect on normal prostate epithelial cells.

Proteomic profiling of the effect of prostate-specific antigen on prostate cancer cells.

BACKGROUND: Prostate-specific antigen (PSA) is a well-known biomarker for diagnosis and management of prostate cancer. PSA has been shown to have anti-angiogenic activity. We used the emerging proteomic research technology to identify proteins in prostate cancer cells whose expression is regulated by enzymatically active PSA. METHODS: Differentially expressed proteins in PC-3M cells treated with PSA were analyzed by 2D-DIGE analysis and identified by HPLC-MS/MS and SEQUEST data mining. Biological network analysis was carried out using MetaCore integrated software designed for functional analysis of experimental data. Gene expression data for several regulated proteins were confirmed by real-time, quantitative PCR. RESULTS: A total of 41 proteins were significantly (P < 0.05) changed in abundance in PC-3M cells in response to PSA treatment. Proteins from 26 gel-spots were identified. Many of the down-regulated proteins including N8 gene product long isoform, laminin receptor, vimentin, DJ-1 and Hsp60 are known to be involved in tumor progression. DISCUSSION: The relevance of the level of PSA in prostate tissue microenvironment and its relation to tumor progression has not been elucidated. PSA has been shown to down-regulate several proteins that are known to have involvement in tumor progression. This suggests that normal physiological levels of PSA in prostate tissue microenvironment may be promoting non-angiogenic environment and its down-regulation may promote tumor growth.

Thiophilic-interaction chromatography of enzymatically active tissue prostate-specific antigen (T-PSA) and its modulation by zinc ions.

Prostate-specific antigen (PSA) is a serine protease secreted both by normal prostate glandular epithelial cells and prostate cancer cells. We explored "thiophilic-interaction chromatography" (TIC) to isolate tissue prostate-specific antigen (T-PSA) from fresh human prostate cancer tissue harvested by radical prostatectomy for the purpose to characterize T-PSA for its enzymatic activity and sensitivity to zinc ions. We have shown, for the first time, that T-PSA has strong affinity for the thiophilic gel (T-gel). The average recovery of T-PSA from T-gel is over 87%. The presence of PSA in the column eluate was confirmed by ELISA and SDS/PAGE. Western blot developed with monoclonal antibody to PSA revealed that T-PSA was predominantly in the "free" form having a molecular weight of 33 kDa. Furthermore, T-PSA was found to be enzymatically active. T-PSA was found to be less enzymatically active as compared to seminal plasma PSA. The inhibition of enzymatic activity of both f-PSA and T-PSA over a wide range of concentrations of Zn(2+) ions (10nM to 50 microM) was comparable. In contrast, the enzymatic activity of chymotrypsin, another serine-protease, was affected differently. At higher concentrations of Zn(2+) (10 microM and higher) the enzymatic activity of chymotrypsin was inhibited, whereas, at lower concentrations of Zn(2+) (5 microM and lower), the enzymatic activity was enhanced.

Interferon inhibitory activity in patients with multiple sclerosis.

BACKGROUND: Interferon inhibitory activity (IIA) is a logical candidate for explaining neutralizing antibody-negative partial responsiveness to interferon beta in multiple sclerosis (MS), but its role has not been evaluated. OBJECTIVE: To investigate the role of IIA and soluble interferon-alpha/beta receptor (sIFNR) in determining response of patients with MS to interferon beta therapy. DESIGN: Parallel-group, open-label study. SETTING: Baird Multiple Sclerosis Center, Buffalo, NY. Patients Blood was obtained before and 24 hours after injection of interferon beta-1a from 38 anti-interferon beta neutralizing antibody-negative patients with relapsing-remitting MS and 16 untreated healthy controls. On the basis of clinical parameters of response to interferon beta therapy, the patients were divided into stable or good-responder (n = 20) and active or partial-responder (n = 18) groups. MAIN OUTCOME MEASURES: Quantitative analyses of magnetic resonance imaging were obtained; the IIA and sIFNR levels were measured using bioassay and enzyme-linked immunosorbent assay, respectively. RESULTS: The IIA and sIFNR levels were elevated in MS patients compared with controls (P<.001). The IIA levels were higher in active or partial responders compared with stable or good responders (P<.001); the sIFNR levels were not different between groups. The Extended Disability Status Score and T2 lesion volumes were higher in the active or partial-responder group compared with the stable or good-responder group. Interferon beta-1a did not have short-term effects on the IIA and sIFNR levels. In univariate general linear model and stepwise regression analyses, IIA levels were associated with T2 lesion volume. CONCLUSION: The levels of IIA are associated with increased MS disease activity and with responsiveness to interferon beta therapy in anti-interferon beta neutralizing antibody-negative MS patients.

Treatment of viral and neoplastic diseases with double-stranded RNA derivatives and other new agents.

Many attempts have been made to inhibit viral and neoplastic diseases by targeting the RNA system. The pathophysiologic significance of the microRNA system and the therapeutic potential of its manipulation are discussed. Studies of double-stranded RNA derivatives are reviewed. The therapeutic potential of one of these compounds, polyI:MPC, is emphasized. Studies of other related antiviral and antineoplastic agents are discussed, including 2'-deoxyoligocytidilates and telomerase inhibitors.