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Effects of an integrated yoga program in modulating perceived stress levels, anxiety, as well as depression levels and radiation-induced DNA damage were studied in 68 breast cancer patients undergoing radiotherapy. Two psychological questionnaires-Hospital Anxiety and Depression Scale (HADS) and Perceived Stress Scale (PSS)-and DNA damage assay were used in the study. There was a significant decrease in the HADS scores in the yoga intervention group, whereas the control group displayed an increase in these scores. Mean PSS was decreased in the yoga group, whereas the control group did not show any change pre-and postradiotherapy. Radiation-induced DNA damage was significantly elevated in both the yoga and control groups after radiotherapy, but the postradiotherapy DNA damage in the yoga group was slightly less when compared to the control group. An integrated approach of yoga intervention modulates the stress and DNA damage levels in breast cancer patients during radiotherapy.

BackgroundSevere acute respiratory syndrome (SARS) emerged in later February 2003, as a new epidemic form of life-threatening infection caused by a novel coronavirus. However, the immune-pathogenesis of SARS is poorly understood. To understand the host response to this pathogen, we investigated the gene expression profiles of peripheral blood mononuclear cells (PBMCs) derived from SARS patients, and compared with healthy controls.ResultsThe number of differentially expressed genes was found to be 186 under stringent filtering criteria of microarray data analysis. Several genes were highly up-regulated in patients with SARS, such as, the genes coding for Lactoferrin, S100A9 and Lipocalin 2. The real-time PCR method verified the results of the gene array analysis and showed that those genes that were up-regulated as determined by microarray analysis were also found to be comparatively up-regulated by real-time PCR analysis.ConclusionsThis differential gene expression profiling of PBMCs from patients with SARS strongly suggests that the response of SARS affected patients seems to be mainly an innate inflammatory response, rather than a specific immune response against a viral infection, as we observed a complete lack of cytokine genes usually triggered during a viral infection. Our study shows for the first time how the immune system responds to the SARS infection, and opens new possibilities for designing new diagnostics and treatments for this new life-threatening disease.

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MicroRNAs (miRNAs) are members of a family of non-coding RNAs of 8-24 nucleotide RNA molecules that regulate target mRNAs. The first miRNAs, lin-4 and let-7, were first discovered in the year 1993 by Ambros, Ruvkun, and co-workers while studying development in Caenorhabditis elegans. miRNAs can play vital functions form C. elegans to higher vertebrates by typical Watson-Crick base pairing to specific mRNAs to regulate the expression of a specific gene. It has been well established that multicellular eukaryotes utilize miRNAs to regulate many biological processes such as embryonic development, proliferation, differentiation, and cell death. Recent studies have shown that miRNAs may provide new insight in cancer research. A recent study demonstrated that more than 50% of miRNA genes are located in fragile sites and cancer-associated genomic regions, suggesting that miRNAs may play a more important role in the pathogenesis of human cancers. Exploiting the emerging knowledge of miRNAs for the development of new human therapeutic applications will be important. Recent studies suggest that miRNA expression profiling can be correlated with disease pathogenesis and prognosis, and may ultimately be useful in the management of human cancer. In this review, we focus on how miRNAs regulate tumorigenesis by acting as oncogenes and anti-oncogenes in higher eukaryotes.

BackgroundA major concern of cancer chemotherapy is the side effects caused by the non-specific targeting of both normal and cancerous cells by therapeutic drugs. Much emphasis has been placed on discovering new compounds that target tumour cells more efficiently and selectively with minimal toxic effects on normal cells.Methodology/Principal FindingsThe cytotoxic effect of thymoquinone, a component derived from the plant Nigella sativa, was tested on human glioblastoma and normal cells. Our findings demonstrated that glioblastoma cells were more sensitive to thymoquinone-induced antiproliferative effects. Thymoquinone induced DNA damage, cell cycle arrest and apoptosis in the glioblastoma cells. It was also observed that thymoquinone facilitated telomere attrition by inhibiting the activity of telomerase. In addition to these, we investigated the role of DNA-PKcs on thymoquinone mediated changes in telomere length. Telomeres in glioblastoma cells with DNA-PKcs were more sensitive to thymoquinone mediated effects as compared to those cells deficient in DNA-PKcs.Conclusions/SignificanceOur results indicate that thymoquinone induces DNA damage, telomere attrition by inhibiting telomerase and cell death in glioblastoma cells. Telomere shortening was found to be dependent on the status of DNA-PKcs. Collectively, these data suggest that thymoquinone could be useful as a potential chemotherapeutic agent in the management for brain tumours.

BackgroundMicroglia, the resident immune cells of the central nervous system (CNS), have two distinct phenotypes in the developing brain: amoeboid form, known to be amoeboid microglial cells (AMC) and ramified form, known to be ramified microglial cells (RMC). The AMC are characterized by being proliferative, phagocytic and migratory whereas the RMC are quiescent and exhibit a slow turnover rate. The AMC transform into RMC with advancing age, and this transformation is indicative of the gradual shift in the microglial functions. Both AMC and RMC respond to CNS inflammation, and they become hypertrophic when activated by trauma, infection or neurodegenerative stimuli. The molecular mechanisms and functional significance of morphological transformation of microglia during normal development and in disease conditions is not clear. It is hypothesized that AMC and RMC are functionally regulated by a specific set of genes encoding various signaling molecules and transcription factors.ResultsTo address this, we carried out cDNA microarray analysis using lectin-labeled AMC and RMC isolated from frozen tissue sections of the corpus callosum of 5-day and 4-week old rat brain respectively, by laser capture microdissection. The global gene expression profiles of both microglial phenotypes were compared and the differentially expressed genes in AMC and RMC were clustered based on their functional annotations. This genome wide comparative analysis identified genes that are specific to AMC and RMC.ConclusionsThe novel and specific molecules identified from the trancriptome explains the quiescent state functioning of microglia in its two distinct morphological states.

Although inhibition of the ubiquitin proteasome system has been postulated to play a key role in the pathogenesis of neurodegenerative diseases, studies have also shown that proteasome inhibition can induce increased expression of neuroprotective heat-shock proteins (HSPs). The global gene expression of primary neurons in response to treatment with the proteasome inhibitor lactacystin was studied to identify the widest range of possible pathways affected. Our results showed changes in mRNA abundance, both at different time points after lactacystin treatment and at different lactacystin concentrations. Genes that were differentially up-regulated at the early time point but not when most cells were undergoing apoptosis might be involved in an attempt to reverse proteasome inhibitor-mediated apoptosis and include HSP70, HSP22 and cell cycle inhibitors. The up-regulation of HSP70 and HSP22 appeared specific towards proteasome inhibitormediated cell death. Overexpression of HSP22 was found to protect against proteasome inhibitor-mediated loss of viability by up to 25%. Genes involved in oxidative stress and the inflammatory response were also up-regulated. These data suggest an initial neuroprotective pathway involving HSPs, antioxidants and cell cycle inhibitors, followed by a proapoptotic response possibly mediated by inflammation, oxidative stress and aberrant activation of cell cycle proteins. Keywords: apoptosis, heat-shock proteins, lactacystin, neurons, proteasome inhibition. A common feature of neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease (PD) is the accumulation of abnormal proteins. However, despite the clear association between abnormal proteins and neurodegenerative diseases, the mechanism of neuronal death in these cases is still undetermined. Studies now suggest that protein aggregation directly impairs the function of the ubiquitin proteasome system (UPS) (Bence et al. 2001) and that dysfunction of the UPS is a possible primary mechanism leading to the pathogenesis of various neurodegenerative disorders .The UPS is the main machinery involved in the nonlysosomal degradation of short-lived, damaged and misfolded intracellular proteins in eukaryotic cells . This pathway involves attachment of multiple ubiquitin molecules to the substrate as a signal for degradation, Abbreviations used: AD, Alzheimer's disease; COX-2, cyclo-oxygenase-2; Cdk, cyclin-dependent kinase; CT, threshold cycle; DMEM, Dulbecco's modified Eagle's medium; EGFP, enhanced green fluorescent protein; GFAP, glial fibrillary acidic protein; HSP, heat-shock protein; LSD, least significant difference; MAP2, microtubule-associated protein 2; MT, metallothionein; MTT, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; PD, Parkinson's disease; ROS, reactive oxygen species; STS, staurosporine; UPS, ubiquitin proteasome system; TBS, Tris-buffered saline.Journal of Neurochemistry, 2005Neurochemistry, , 94, 943-956 doi:10.1111Neurochemistry, /j.1471Neurochemistry, -4159.2005