Current Issue : January - March Volume : 2014 Issue Number : 1 Articles : 6 Articles
Background: The cancer stem cell (CSC) theory proposes that tumours arise from and are sustained by a\r\nsubpopulation of cells with both cancer and stem cell properties. One of the key hallmarks of CSCs is the ability to\r\ngrow anchorage-independently under serum-free culture conditions resulting in the formation of tumourspheres.\r\nIt has further been reported that these cells are resistant to traditional chemotherapeutic agents.\r\nMethods: In this study, the tumoursphere assay was validated in MCF-7 cells and used to screen novel marine algal\r\ncompounds for potential anti-cancer stem cell (CSC) activity in vitro.\r\nResults: MCF-7 breast cancer cells were observed to generate tumourspheres or mammospheres after 3-5 days\r\ngrowth in anchorage-independent conditions and an apparent enrichment in potential CSCs was observed by an\r\nincrease in the proportion of CD44high/CD24low marker-bearing cells and Oct4 expression compared to those in the\r\nbulk population grown in regular adherent conditions. Using this assay, a set of algal metabolites was screened for\r\nthe ability to inhibit mammosphere development as a measure of potential anti-CSC activity. We report that the\r\npolyhalogenated monoterpene stereoisomers RU017 and RU018 isolated from the red alga Plocamium cornutum,\r\nboth of which displayed no cytotoxicity against either adherent MCF-7 breast cancer or MCF-12A non-transformed\r\nbreast epithelial cells, were able to prevent MCF-7 mammosphere formation in vitro. On the other hand, neither the\r\nbrown algal carotenoid fucoxanthin nor the chemotherapeutic paclitaxel, both of which were toxic to adherent\r\nMCF-7 and MCF-12A cells, were able to inhibit mammosphere formation. In fact, pre-treatment with paclitaxel\r\nappeared to enhance mammosphere formation and development, a finding which is consistent with the reported\r\nresistance of CSCs to traditional chemotherapeutic agents.\r\nConclusion: Due to the proposed clinical significance of CSC in terms of tumour initiation and metastasis,\r\nthe identification of agents able to inhibit this subpopulation has clinical significance....
Understanding the mechanisms that maintain protective antibody levels after immunisation is important for vaccine\r\ndesign. In this study, we have determined the kinetics of plasma and memory B cells detectable in the blood of\r\ncattle immunised with model T-dependent or T-independent antigens. Immunisation with the T-D antigen resulted\r\nin an expansion of TNP-specific plasma cells post-TNP primary and booster immunisations, which was associated\r\nwith increased titres of TNP-specific IgG antibodies. Although no TNP-specific memory B cells were detected in the\r\nT-D group following the primary immunisation, we detected an increase in the number of TNP-specific memory B\r\ncells post-TNP boost. In contrast, no TNP-specific plasma or memory B cells were detected after primary or\r\nsecondary immunisation with the T-I antigen. We then investigated if immunisation with a third party antigen\r\n(tetanus toxin fragment C, TTC) would result in a bystander stimulation and increase the number of TNP-specific\r\nplasma and memory B cells in the T-D and/or T-I group. TTC immunisation in the T-D group resulted in a small\r\nincrease in the number of TNP-specific plasma cells post-TTC primary immunisation and boost, and in an increase\r\nin the number of TNP-specific memory B cells post-TTC boost. This bystander effect was not observed in the\r\nanimals previously immunised with the T-I antigen. In conclusion, the present study characterised for the first time\r\nthe B cell response in cattle to immunisation with T-D and T-I antigens and showed that bystander stimulation of\r\nan established T-D B cell memory response may occur in cattle....
Abstract: Extranodal natural killer (NK)/T-cell lymphoma, nasal type, is an uncommon lymphoma associated with\r\nthe Epstein-Barr virus (EBV). It most commonly involves the nasal cavity and upper respiratory tract. Primary\r\npulmonary NK/T cell lymphoma is extremely rare. If a patient with a NK or T-cell tumor has an unusual reaction to\r\ntreatment or an unusual prognosis, it is wise to differentiate NK from T-cell tumors. The clinicopathologic\r\ncharacteristics, immunophenotype, EBV in situ hybridization, and T cell receptor (TCR) gene rearrangement of\r\nprimary pulmonary NK cell lymphoma from a 73-year-old Chinese woman were investigated and the clonal status\r\nwas determined using female X-chromosomal inactivation mosaicism and polymorphisms at the phosphoglycerate\r\nkinase (PGK) gene. The lesion showed the typical histopathologic characteristics and immunohistochemical features\r\nof NK/T cell lymphoma. However, the sample was negative for TCR gene rearrangement. A clonality assay\r\ndemonstrated that the lesion was monoclonal. It is concluded that this is the first recorded case of genuine primary\r\npulmonary NK cell lymphoma. The purpose of the present work is to recommend that pathologists carefully\r\ninvestigate the whole lesion to reduce the likelihood that primary pulmonary NK cell lymphoma will be\r\nmisdiagnosed as an infectious lesion. In addition, TCR gene rearrangement and clonal analysis, which is based on\r\nfemale X-chromosomal inactivation mosaicism and polymorphisms at PGK and androgen receptor (AR) loci, were\r\nfound to play important roles in differentiating NK cell lymphoma from T cell lymphoma.\r\nVirtual slides: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/\r\nvs/5205300349457729....
Natural products are important leads in drug discovery, represent a reservoir of diverse templates and are being tapped to outsource novel anticancer agents many other plants have been examined to identify new and effective anti cancer compounds. The purpose of present study was designed to investigate cytotoxic activity of hydromethanolic leaf extract of syzygiumjambos (L) Alston, in-vitro cytotoxic evaluation was determined by using MTT assay on MCF-7 (Breast Cancer); HT-29 (Human colorectal cancer) A-549 cell lines (Human lung cancer) and Vero cell lines. To determine cytotoxic activity various concentration of plant extract were used. Test drug was separately dissolved in distilled DMSO and volume was made up with DMEM supplemented with 2% inactivated FBS to obtain a stock solution of 1 mg/ml concentration and sterilized by filtration. Serial two fold dilutions were prepared from this for carrying out cytotoxic studies. By using ELISA reader wavelength measured at 540 nm and percentage of cell inhibition was determined by plotting a graph of concentration vs. percentage of inhibition. The concentration of plant extract required to inhibit 50 % of cell growth (IC 50) values was determined....
Background: Gamijinhae-tang (GJHT) has long been used in Korea to treat respiratory diseases. The therapeutic\r\neffect of GJHT is likely associated with its anti-inflammatory activity. However, the precise mechanisms underlying\r\nits effects are unknown. This study was conducted to evaluate the protective effects of GJHT in a porcine\r\npancreatic elastase (PPE) and lipopolysaccharide(LPS) induced animal model of acute lung injury (ALI).\r\nMethods: In this study, mice were intranasally exposed to PPE and LPS for 4 weeks to induce chronic obstructive\r\npulmonary disease (COPD)-like lung inflammation. Two hours prior to PPE and LPS administration, the treatment\r\ngroup was administered GJHT extracts via an oral injection. The numbers of neutrophils, lymphocytes, macrophages\r\nand total cells in the bronchoalveolar lavage (BAL) fluid were counted, and pro-inflammatory cytokines were also\r\nmeasured. For histologic analysis, hematoxylin and eosin (H&E) stains and periodic acid-Schiff (PAS) stains were\r\nevaluated.\r\nResults: After inducing ALI by treating mice with PPE and LPS for 4 weeks, the numbers of neutrophils,\r\nlymphocytes and total cells were significantly lower in the GJHT group than in the ALI group. In addition, the IL-1�Ÿ\r\nand IL-6 levels were significantly decreased in the GJHT group. The histological results also demonstrated the\r\nattenuation effect of GJHT on PPE- and LPS-induced lung inflammation.\r\nConclusions: The results of this study indicate that GJHT has significantly reduces PPE- and LPS-induced lung\r\ninflammation. The remarkable protective effects of GJHT suggest its therapeutic potential in COPD treatment....
Background: Oral immunization with vaccines may be an effective strategy for prevention of Clostridium difficile\r\ninfection (CDI). However, application of previously developed vaccines for preventing CDI has been limited due\r\nto various reasons. Here, we developed a recombinant Lactococcus lactis oral vaccine and evaluated its effect on\r\na C. difficile-infected animal model established in golden hamsters in attempt to provide an alternative strategy\r\nfor CDI prevention.\r\nMethods: Recombinant L. lactis vaccine was developed using the pTRKH2 plasmid, a high-copy-number\r\nEscherichia coli-L. shuttle vector: 1) L. lactis expressing secreted proteins was constructed with recombinant\r\npTRKH2 (secreted-protein plasmid) carrying the Usp45 signal peptide (SPUsp45), nontoxic adjuvanted tetanus\r\ntoxin fragment C (TETC), and 14 of the 38 C-terminal repeats (14CDTA) of nontoxic C. difficile toxin A (TcdA); and\r\n2) L. lactis expressing secreted and membrane proteins was constructed with recombinant pTRKH2 (membrane-anchored\r\nplasmid) carrying SPUsp45, TETC, 14CDTA, and the cell wall-anchored sequence of protein M6 (cwaM6). Then, 32 male\r\nSyrian golden hamsters were randomly divided into 4 groups (n = 8 each) for gavage of normal saline (blank control) and\r\nL. lactis carrying the empty shuttle vector, secreted-protein plasmid, and membrane-anchored plasmid, respectively. After\r\n1-week gavage of clindamycin, the animals were administered with C. difficile spore suspension. General symptoms and\r\nintestinal pathological changes of the animals were examined by naked eye and microscopy, respectively. Protein levels\r\nof anti-TcdA IgG/IgA antibodies in intestinal tissue and fluid were analyzed by enzyme-linked immunosorbent assay\r\n(ELISA). A cell culture cytotoxicity neutralization assay was done by TcdA treatment with or without anti-TcdA serum\r\npre-incubation or treatment. Apoptosis of intestinal epithelial cells was examined by flow cytometry (FL) assay.\r\nExpression of mucosal inflammatory cytokines in the animals was detected by polymer chain reaction (PCR) assay....
Loading....