Kailash C. Chadha

Gene expression of angiogenic factors correlates with metastatic potential of prostate cancer cells.

We hypothesize that expression of proangiogenic genes correlates with the metastatic potential of prostate cancer cells. LNCaP, DU-145, and PC-3 are prostate cancer cell lines with low, moderate, and high metastatic potential, respectively, as we demonstrated by their capacity to invade an extracellular matrix, an established tumor invasion assay. The constitutive gene expression of the proangiogenic factors, vascular endothelial growth factor, intercellular adhesion molecule-1, interleukin-8, and transforming growth factor-β2, was significantly greater in the more metastatic DU-145 and PC-3 cells as compared with LNCaP cells. Matrix metalloproteinase (MMP)-9 is thought to contribute to the invasive phenotype of tumor cells. PC-3 cells showed increased expression of MMP-9 and membrane type 4-MMP as compared with LNCaP and DU-145. Tissue inhibitors of metalloproteinase 1 and 4 gene expression were elevated in DU-145 and PC-3 cells, but paradoxically, LNCaP cells had undetectable levels of these genes. We transfected and overexpressed MMP-9 in poorly metastatic LNCaP cells and measured their invasive activity. Transient expression of human MMP-9 in LNCaP cells produced a 3–5-fold increase in MMP-9 activity with a comparable increase in invasiveness. Antisense ablation of the expression of MMP-9 in DU-145 and PC-3 cells produced concomitant inhibition of the gene expression of the proangiogenic factors, vascular endothelial growth factor, and intercellular adhesion molecule-1 (ICAM-1). Treatment of DU-145 and PC-3 cells with a selective chemical inhibitor of MMP-9 proteinase activity also inhibited their invasive activity. These results support our hypothesis that metastatic potential of prostate cancer cells correlates with expression of proangiogenic factors.

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

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 quercetins action.

The flavonoid, quercetin, differentially regulates Th-1 (IFNγ) and Th-2 (IL4) cytokine gene expression by normal peripheral blood mononuclear cells

Flavonoids are plant metabolites that are dietary antioxidants and exert significant anti-tumor, anti-allergic, anti-inflammatory and anti-viral effects. It is generally accepted that Th-1 derived cytokines such as IL-2, IFNgamma and IL-12 promote cellular immunity while Th-2 derived cytokines such as IL-4, IL-5, IL-6 exert negative immunoregulatory effects on cellular immunity while upregulating humoral immunity. The molecular mechanisms underlying the biological activities of flavonoids have not been elucidated. We hypothesize that the flavonoid, quercetin, exert significant anti-viral and anti-tumor effects possibly by modulating the production of Th-1 and Th-2 derived cytokines. Peripheral blood mononuclear cells (PBMC, 1 x 10(6) cells/ml) from normal subjects were cultured with different concentrations of quercetin (0.5-50 microM) for 24-72 h and supernates were quantitated for IFN-gamma and IL-4 by ELISA and antiviral activity of IFNgamma by bioassay. FACS analysis was done to determine the number of IFN-gamma and IL-4 positive cells and RT-PCR was done to quantitate gene expression. Quercetin significantly induces the gene expression as well as the production of Th-1 derived IFNgamma and the downregulates Th-2 derived IL-4 by normal PBMC. Further, quercetin treatment increased the phenotypic expression of IFNgamma cells and decreased IL-4 positive cells by FACS analysis, which corroborate with protein secretion and gene expression studies. These results suggest that the beneficial immuno-stimulatory effects of quercetin may be mediated through the induction of Th-1 derived cytokine, IFNgamma, and inhibition of Th-2 derived cytokine, IL-4.

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.

Cocaine Differentially Modulates Chemokine Production by Mononuclear Cells from Normal Donors and Human Immunodeficiency Virus Type 1-Infected Patients

ABSTRACT Earlier studies have supported a significant role for cocaine in the susceptibility to and the progression of human immunodeficiency virus type 1 (HIV-1) infection. Recently, several unique HIV-1 entry coreceptors (e.g., CCR5 and CCR3) and a trio of HIV-1-specific suppressor chemokines, namely, RANTES (regulated-upon-activation T expressed and secreted), macrophage inflammatory protein 1α (MIP-1α) and MIP-1β, were identified. Although cocaine has been linked to the immunopathogenesis of HIV-1 infection, the corresponding cellular and molecular mechanism(s) have not been well defined. We hypothesize that cocaine mediates these pathologic effects through the downregulation of HIV-1-suppressing chemokines and/or upregulating HIV-1 entry coreceptors in HIV-1-infected subjects, resulting in disease progression to AIDS. Our results show that cocaine selectively downregulates endogenous MIP-1β secretion by normal peripheral blood mononuclear cells (PBMC), while cocaine did not affect the MIP-1β production by PBMC from AIDS patients. Cocaine also selectively suppresses lipopolysaccharide-induced MIP-1β production by PBMC from HIV-infected patients. Further, cocaine significantly downregulates endogenous MIP-1β gene expression, while it upregulates HIV-1 entry coreceptor CCR5 by normal PBMC. These studies suggests a role for cocaine as a cofactor in the pathogenesis of HIV infection and support the premise that cocaine increases susceptibility to and progression of HIV-1 infection by inhibiting the synthesis of HIV-1 protective chemokines and/or upregulating the HIV-1 entry coreceptor, CCR5.

Soluble receptor for advanced glycation end products in multiple sclerosis: a potential marker of disease severity.

Objectives To compare serum levels of the receptor for advanced glycation end products (sRAGE) between multiple sclerosis (MS) patients and healthy control subjects, and to investigate whether serum sRAGE levels correlate with MS disease severity as indicated by the Kurtzke Expanded Disability Status Scale (EDSS). Method 37 patients with clinical diagnosis of MS and 22 healthy control subjects were investigated in a cross-sectional study using enzyme-linked immunosorbent assays (ELISA). Results Serum levels of sRAGE were found to be significantly lower in MS patients compared to levels in healthy controls (p = 0.005). A trend toward lower levels of serum sRAGE was observed in female MS patients compared to their male counterparts (p = 0.05). A relationship between sRAGE and EDSS, and sRAGE and rate of clinical relapse was observed (p = 0.012). Conclusion The significant reduction of sRAGE in MS patients relative to healthy controls supports the potential role for RAGE axis in MS clinical pathology. Lower levels of sRAGE may be associated with enhanced inflammatory responses. Based on these observations, further investigations into the role of sRAGE in MS clinical pathology is warranted.

Effect of alcohol on spleen cells and their functions in C57BL/6 mice

Spleen cells from C57BL/6 mice maintained on alcohol containing liquid diet for two weeks were evaluated for different immune functions. On an average, 22% fewer spleen cells were recovered from alcohol-fed mice when compared to cells from control animals. In alcohol-fed mice, the relative frequency of B cells increased, whereas total T cells including CD4+ cells decreased significantly. Alcoholic mice, when challenged with poly(rI) poly(rC), produced significantly less interferon than control mice. In vitro production of interferon alpha and gamma by the spleen cells of alcoholic mice was reduced by 67-90%. No significant differences were seen in the level of natural killer cell activity in spleen cells of control and alcoholic mice. These results suggest that chronic alcohol intake can result in not only changes in the number of immune cells, but more importantly affect their biological functions such as their ability to produce interferons.

Regulation of PSA secretion and survival signaling by calcium-independent phopholipase A2β in prostate cancer cells

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.

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.

Free interferon‐α/β receptors in the circulation of patients with adenocarcinoma

Many viral and neoplastic diseases are resistant to interferon‐α/β (IFN‐α/β) therapy or develop resistance during the course of IFN treatment. In patients with viral diseases, the authors identified four IFN inhibitors, of which the most important, most likely is a free IFN receptor of type 1 appearing in the circulation that captures and neutralizes IFN‐α/β.