Neoplastic transformation appears to be a multi-step process in which the normal controls of cell proliferation and cell-cell interaction are lost, thus transforming normal cells into cancer. The tumorigenic process involves the interplay between oncogenes and tumour suppressor genes. In this study, we have selected the ras family, c-myc and epidermal growth factor receptor (EGFR) genes to detect whether their abnormalities are associated with the expression and progression of glioma cases in Malay patients. We have used the polymerase chain reaction-single stranded conformation polymorphism followed by direct sequencing for the study. For the ras gene family, we screened the point mutations in codons 12 and 61 of the H-, K-, and N-ras gene; for EGFR and c-myc, we analyzed only the exon 1 in glioma samples. In mutational screening analyses of the ras family, c-myc and EGFR gene, there was no mobility shift observed in any tumour analyzed. All patterns of single stranded conformation polymorphism (SSCP) band observed in tumour samples were normal compared to those in normal samples. The DNA sequencing results in all high-grade tumours showed that all base sequences were normal. All 48 patients survived after five years of treatment. In simple logistic regression analysis, variables which were found to be significant were hemiplegia (p=0.047) and response radiotherapy (p=0.003). Hemiplegics were 25 times more likely to have high pathological grade compared to those without. Patients with vascular involvement were 5.5 times more likely to have higher pathological grade. However, these findings were not significant in multivariate analysis. Patients who had radiotherapy were nearly 14 times more likely to have higher pathological grade. Multivariate analysis revealed that patients with hemiplegia were more likely to have higher pathological grade (p= 0.008). Those with higher pathological grading were 80 times more likely to have radiotherapy (p=0.004).
Ras gene; c-myc; EGFR; Gliomas; Malaysia
The kava-kava plant (Piper methsyticum) is traditionally known as the pacific elixir by the pacific islanders for its role in a wide range of biological activities. The extract of the roots of this plant contains a variety of interesting molecules including Flavokawain A and this molecule is known to have anti-cancer properties. Breast cancer is still one of the leading diagnosed cancers in women today. The metastatic process is also very pertinent in the progression of tumorigenesis.
MCF-7 and MDA-MB231 cells were treated with several concentrations of FKA. The apoptotic analysis was done through the MTT assay, BrdU assay, Annexin V analysis, cell cycle analysis, JC-1 mitochondrial dye, AO/PI dual staining, caspase 8/9 fluorometric assay, quantitative real time PCR and western blot. For the metastatic assays, the in vitro scratch assay, trans-well migration/invasion assay, HUVEC tube formation assay, ex vivo rat aortic ring assay, quantitative real time PCR and western blot were employed.
We have investigated the effects of FKA on the apoptotic and metastatic process in two breast cancer cell lines. FKA induces apoptosis in both MCF-7 and MDA-MB231 in a dose dependent manner through the intrinsic mitochondrial pathway. Additionally, FKA selectively induces a G2/M arrest in the cell cycle machinery of MDA-MB231 and G1 arrest in MCF-7. This suggests that FKA's anti-cancer activity is dependent on the p53 status. Moreover, FKA also halted the migration and invasion process in MDA-MB231. The similar effects can be seen in the inhibition of the angiogenesis process as well.
FKA managed to induce apoptosis and inhibit the metastatic process in two breast cancer cell lines, in vitro. Overall, FKA may serve as a promising candidate in the search of a new anti-cancer drug especially in halting the metastatic process but further in vivo evidence is needed.
Feline Infectious Peritonitis (FIP) is a severe fatal immune-augmented disease in cat population. It is caused by FIP virus (FIPV), a virulent mutant strain of Feline Enteric Coronavirus (FECV). Current treatments and prophylactics are not effective. The in vitro antiviral properties of five circular Triple-Helix Forming Oligonucleotide (TFO) RNAs (TFO1 to TFO5), which target the different regions of virulent feline coronavirus (FCoV) strain FIPV WSU 79-1146 genome, were tested in FIPV-infected Crandell-Rees Feline Kidney (CRFK) cells. RT-qPCR results showed that the circular TFO RNAs, except TFO2, inhibit FIPV replication, where the viral genome copy numbers decreased significantly by 5-fold log10 from 1014 in the virus-inoculated cells to 109 in the circular TFO RNAs-transfected cells. Furthermore, the binding of the circular TFO RNA with the targeted viral genome segment was also confirmed using electrophoretic mobility shift assay. The strength of binding kinetics between the TFO RNAs and their target regions was demonstrated by NanoITC assay. In conclusion, the circular TFOs have the potential to be further developed as antiviral agents against FIPV infection.
Pasteurella multocida serotypes B:2 and E:2 are the main causative agents of ruminant hemorrhagic septicemia in Asia and Africa, respectively. Pasteurella multocida strain PMTB was isolated from a buffalo with hemorrhagic septicemia and has been determined to be serotype B:2. Here we report the draft genome sequence of strain PMTB.
In order to develop a systemically administered safe and effective nonviral gene delivery system against avian influenza virus (AIV) that induced cytokine expression, the hemagglutinin (H5) gene of AIV, A/Ck/Malaysia/5858/04 (H5N1) and green fluorescent protein were cloned into a coexpression vector pIRES (pIREGFP-H5) and formulated using green synthesis of silver nanoparticles (AgNPs) with poly(ethylene glycol) and transfected into primary duodenal cells taken from 18-day-old specific-pathogen-free chick embryos. The AgNPs were prepared using moderated temperature and characterized for particle size, surface charge, ultraviolet-visible spectra, DNA loading, and stability. AgNPs and AgNP-pIREGFP-H5 were prepared in the size range of 13.9 nm and 25 nm with a positive charge of +78 ± 0.6 mV and +40 ± 6.2 mV, respectively. AgNPs with a positive surface charge could encapsulate pIREGFP-H5 efficiently. The ultraviolet-visible spectra for AgNP-pIREGFP-H5 treated with DNase I showed that the AgNPs were able to encapsulate pIREGFP-H5 efficiently. Polymerase chain reaction showed that AgNP-pIREGFP-H5 entered into primary duodenal cells rapidly, as early as one hour after transfection. Green fluorescent protein expression was observed after 36 hours, peaked at 48 hours, and remained stable for up to 60 hours. In addition, green fluorescent protein expression generally increased with increasing DNA concentration and time. Cells were transfected using Lipocurax in vitro transfection reagent as a positive control. A multiplex quantitative mRNA gene expression assay in the transfected primary duodenal cells via the transfection reagent and AgNPs with pIREGFP-H5 revealed expression of interleukin (IL)-18, IL-15, and IL-12â.
silver nanoparticles; avian influenza; hemagglutinin; transfection; primary cells
Marine microalgae have been prominently featured in cancer research. Here, we examined cytotoxic effect and apoptosis mechanism of crude ethanol extracts of an indigenous microalga, Chaetoceros calcitrans (UPMAAHU10) on human breast cell lines. MCF-7 was more sensitive than MCF-10A with IC50 value of 3.00 ± 0.65, whilst the IC50 value of Tamoxifen against MCF-7 was 12.00 ± 0.52 μg/mL after 24 hour incubation. Based on Annexin V/Propidium iodide and cell cycle flow cytometry analysis, it was found that inhibition of cell growth by EEC on MCF-7 cells was through the induction of apoptosis without cell cycle arrest. The apoptotic cells at subG0/G1 phase in treated MCF-7 cells at 48 and 72 hours showed 34 and 16 folds increased compared to extract treated MCF-10A cells which showed only 6 and 7 folds increased at the same time points, respectively. Based on GeXP study, EEC induced apoptosis on MCF-7 cells via modulation of CDK2, MDM2, p21Cip1, Cyclin A2, Bax and Bcl-2. The EEC treated MCF-7 cells also showed an increase in Bax/Bcl-2 ratio that in turn activated the caspase-dependent pathways by activating caspase 7. Thus, marine microalga, Chaetoceros calcitrans may be considered a good candidate to be developed as a new anti-breast cancer drug.
Attenuated Salmonella has been used as a carrier for DNA vaccine. However, in vitro and in vivo studies on the bacteria following transfection of plasmid DNA were poorly studied. In this paper, eukaryotic expression plasmids encoding avian influenza virus (AIV) subtype H5N1 genes, pcDNA3.1/HA, NA, and NP, were transfected into an attenuated Salmonella enteric typhimurium SV4089. In vitro stability of the transfected plasmids into Salmonella were over 90% after 100 generations. The attenuated Salmonella were able to invade MCF-7 (1.2%) and MCF-10A (0.5%) human breast cancer cells. Newly hatched specific-pathogen-free (SPF) chicks were inoculated once by oral gavage with 109 colony-forming unit (CFU) of the attenuated Salmonella. No abnormal clinical signs or deaths were recorded after inoculation. Viable bacteria were detected 3 days after inoculation by plating from spleen, liver, and cecum. Fluorescent in situ hybridization (FISH) and polymerase chain reaction (PCR) were carried out for confirmation. Salmonella was not detected in blood cultures although serum antibody immune responses to Salmonella O antiserum group D1 factor 1, 9, and 12 antigens were observed in all the inoculated chickens after 7 days up to 35 days. Our results showed that live attenuated S. typhimurium SV4089 harboring pcDNA3.1/HA, NA, and NP may provide a unique alternative as a carrier for DNA oral vaccine in chickens.
Avian influenza viruses (AIV), the causative agent of avian flu or bird flu, cause widespread morbidity and mortality in poultry. The symptoms of the disease range from mild flu like symptoms to death. These viruses possess two important surface glycoproteins, namely hemagglutinin (HA) and neuraminidase (NA) against which neutralizing antibodies are produced. Due to the highly mutative nature of the genes which encode these proteins, the viruses often confer resistance to the current anti-viral drugs making the prevention and treatment of infection challenging. In our laboratory, we have recently identified a novel anti-viral peptide (P1) against the AIV H9N2 from a phage displayed peptide library. This peptide inhibits the replication of the virus in ovo and in vitro by its binding to the HA glycoprotein. In the current study, we demonstrate that the peptide inhibits the virus replication by preventing the attachment to the host cell but it does not have any effect on the viral fusion. The reduction in the viral nucleoprotein (NP) expression inside the host cell has also been observed during the peptide (P1) treatment. This novel peptide may have the potential to be developed as a therapeutic agent for the treatment and control of avian influenza virus H9N2 infections.
Influenza; peptide inhibitors; fluorescence microscopy; flow cytometry
Newcastle disease virus (NDV) is one of the most economically important avian virus which affects the poultry industry worldwide. Although NDV is being very actively studied in Malaysia, there are still no studies on its potential as an anticancer agent, a new approach to treating cancer known as virotherapy. Currently, a collaborative research is being undertaken between Universiti Putra Malaysia (UPM), Universiti Sains Malaysia (USM) and Majlis Kanser Nasional (MAKNA) in characterising various local NDV isolates as anticancer agent. This paper describes an overview of the research that have been carried out worldwide in the use of NDV for cancer treatment and also some of our findings in characterising local NDVs with oncolytic properties.
Newcastle disease virus; anticancer agent; apoptosis
Vitamin C is generally thought to enhance immunity and is widely taken as a supplement especially during cancer treatment. Tamoxifen (TAM) has both cytostatic and cytotoxic properties for breast cancer. TAM engaged mitochondrial oestrogen receptor beta in MCF-7 cells and induces apoptosis by activation of pro-caspase-8 followed by downstream events, including an increase in reactive oxygen species and the release of pro-apoptotic factors from the mitochondria. In addition to that, TAM binds with high affinity to the microsomal anti-oestrogen-binding site and inhibits cholesterol esterification at therapeutic doses. This study aimed to investigate the role of vitamin C in TAM-mediated apoptosis. Cells were loaded with vitamin C by exposure to dehydroascorbic acid, thereby circumventing in vitro artefacts associated with the poor transport and pro-oxidant effects of ascorbic acid. Pre-treatment with vitamin C caused a dose-dependent attenuation of cytotoxicity, as measured by acridine-orange/propidium iodide (AO/PI) and Annexin V assay after treatment with TAM. Vitamin C dose-dependently protected cancer cells against lipid peroxidation caused by TAM treatment. By real-time PCR analysis, an impressive increase in FasL and tumour necrosis factor-α (TNF-α) mRNA was detected after TAM treatment. In addition, a decrease in mitochondrial transmembrane potential was observed. These results support the hypothesis that vitamin C supplementation during cancer treatment may detrimentally affect therapeutic response.
vitamin C; tamoxifen; breast cancer; ROS; free radical; apoptosis; lipid peroxidation
The influenza virus (IV) is known to be a resistant virus with frequent mutations, causing severe respiratory diseases in the upper respiratory system. Public health concerns about clinical efficacy of all conventional drugs are ambiguous; therefore, finding additional therapeutic agents is critical to prevent and control influenza outbreaks. Influenza is associated with the induction of proinflammatory cytokines. Scientists have reported that anti-inflammatory drugs, with pleiotropic effects, reduce the burden of severe influenza diseases. Therefore, statins, which are cardioprotective drugs with anti-inflammatory and immunomodulatory effects, may help patients suffering from influenza virus (IV). This review delineates the potential use of statins as an alternative therapy in treating influenza related illness.
Polymerase chain reaction-enzyme linked immunosorbent assay (PCR-ELISA) is an immunodetection method that can quantify PCR product directly after immobilization of biotinylated DNA on a microplate. This method, which detects nucleic acid instead of protein, is a much more sensitive method compared to conventional PCR method, with shorter analytical time and lower detection limit. Its high specificity and sensitivity, together with its semiquantitative ability, give it a huge potential to serve as a powerful detection tool in various industries such as medical, veterinary, and agricultural industries. With the recent advances in PCR-ELISA, it is envisaged that the assay is more widely recognized for its fast and sensitive detection limit which could improve overall diagnostic time and quality.
Prolonged standing has been hypothesized as a vital contributor to discomfort and muscle fatigue in the workplace. The objective of this study was to develop a decision support system that could provide systematic analysis and solutions to minimize the discomfort and muscle fatigue associated with prolonged standing.
The integration of object-oriented programming and a Model Oriented Simultaneous Engineering System were used to design the architecture of the decision support system.
Validation of the decision support system was carried out in two manufacturing companies. The validation process showed that the decision support system produced reliable results.
The decision support system is a reliable advisory tool for providing analysis and solutions to problems related to the discomfort and muscle fatigue associated with prolonged standing. Further testing of the decision support system is suggested before it is used commercially.
decision support system; discomfort; ergonomics; fatigue; prolonged standing
Influenza A virus is one of the most important health risks that lead to significant respiratory infections. Continuous antigenic changes and lack of promising vaccines are the reasons for the unsuccessful treatment of influenza. Statins are pleiotropic drugs that have recently served as anti-influenza agents due to their anti-inflammatory activity. In this study, the effect of simvastatin on influenza A-infected cells was investigated. Based on the MTT cytotoxicity test, hemagglutination (HA) assay and qPCR it was found that simvastatin maintained cell viability and decreased the viral load significantly as compared to virus-inoculated cells. The expression of important pro-inflammatory cytokines (tumor necrosis factor-α, interleukin-6 and interferon-γ), which was quantified using ELISA showed that simvastatin decreased the expression of pro-inflammatory cytokines to an average of 2-fold. Furthermore, the modulation of actin filament polymerization was determined using rhodamine staining. Endocytosis and autophagy processes were examined by detecting Rab and RhoA GTPase protein prenylation and LC3 lipidation using western blotting. The results showed that inhibiting GTPase and LC3 membrane localization using simvastatin inhibits influenza replication. Findings of this study provide evidence that modulation of RhoA, Rabs and LC3 may be the underlying mechanisms for the inhibitory effects of simvastatin as an anti-influenza compound.
statin; influenza; cytokine; actin; RhoA; endocytosis; Rab; autophagy; inhibition
Influenza virus is still a severe respiratory disease affecting human and other species. As conventional drugs are not recommended for long time because of side effects and drug resistance occurrence, traditional medication has been focused as alternative remedy. HESA-A is a natural compound from herbal-marine origin. Previous studies have reported the therapeutic properties of HESA-A on psoriasis vulgaris and different types of cancers and we also showed its anti-inflammatory effects against influenza A infection.
This study was designed to investigate the potential properties of HESA-A as prophylaxis or treatment. To investigate the prophylaxis or treatment activities of HESA-A, Madin-Darby Canine Kidney (MDCK) cells were exposed to HESA-A and influenza A virus in different manners of exposure and different time intervals. The results were evaluated by MTT and HA assays.
It was found that HESA-A is much more effective against influenza cytopathic effects when it is applied for prophylaxis and also in concurrent treatment (p ≤ 0.05) but not in post-infection treatment (p ≥ 0.05).
In conclusion, HESA-A is significantly effective against influenza replication in prophylaxis application affecting the virus penetration/adsorption to the cell without any toxic effect on the cell viability.
HESA-A; H1N1; Influenza virus; HA; MTT
Immunomodulators are agents that are able to stimulate or inhibit the immune response. The leaf extracts from Potentilla indica and Dendrophthoe pentandra were analyzed in vitro for immunomodulatory activity and an MTT colorimetric assay was conducted to determine the proliferation of mice splenocytes and thymocytes. A bromodeoxyuridine assay was performed to analyze DNA synthesis and the Trypan blue exclusion method was conducted to evaluate the changes in total cell population. The results indicated that treatment with P. indica and D. pentandra produced a time- and dose-dependent increase in cell viability and proliferation. Following 72 h of treatment with P. indica and D. pentandra, thymocyte proliferation was augmented by 18 and 41%, respectively and splenocyte proliferation increased by 35 and 42%, respectively, when compared with untreated cells. The present study demonstrated that these extracts may act as potential immunostimulants and, thus, represent an alternative source of immunomodulatory compounds for the treatment of human immune-mediated diseases.
immunomodulatory; Rosaceae; mistletoe; bromodeoxyuridine assay; MTT; spleen; thymus
Damnacanthal, an anthraquinone compound, is isolated from the roots of Morinda citrifolia L. (noni), which has been used for traditional therapy in several chronic diseases, including cancer. Although noni has long been consumed in Asian and Polynesian countries, the molecular mechanisms by which it exerts several benefits are starting to emerge. In the present study, the effect of damnacanthal on MCF-7 cell growth regulation was investigated. Treatment of MCF-7 cells with damnacanthal for 72 h indicated an antiproliferative activity. The MTT method confirmed that damnacanthal inhibited the growth of MCF-7 cells at the concentration of 8.2 μg/ml for 72 h. In addition, the drug was found to induce cell cycle arrest at the G1 checkpoint in MCF-7 cells by cell cycle analysis. Damnacanthal induced apoptosis, determined by Annexin V-fluorescein isothiocyanate/propidium iodide (PI) dual-labeling, acridine-orange/PI dyeing and caspase-7 expression. Furthermore, damnacanthal-mediated apoptosis involves the sustained activation of p21, leading to the transcription of p53 and the Bax gene. Overall, the present study provided significant evidence demonstrating that p53-mediated damnacanthal induced apoptosis through the activation of p21 and caspase-7.
damnacanthal; MCF-7; anticancer; caspase; p53; p21; apoptosis
Immunotherapy has raised the attention of many scientists because it hold promise to be an attractive therapeutic strategy to treat a number of disorders. In this study, the immunomodulatory effects of low titers of Newcastle disease virus (NDV) AF2240 on human peripheral blood mononuclear cells (PBMC) were analyzed. We evaluated cytokine secretion and PBMC activation by cell proliferation assay, immunophenotyping and enzyme linked immunosorbent assay. The proliferation of the human PBMC was measured to be 28.5% and 36.5% upon treatment with 8 hemaglutinin unit (HAU) and 2 HAU of NDV respectively. Interestingly, the percentage of cells with activating markers CD16 and CD56 were increased significantly. Furthermore, the intracellular perforin and granzyme levels were also increased upon virus infection. Human PBMC treated with NDV titer 8 HAU was found to stimulate the highest level of cytokine production including interferon-γ, interleukin-2 and interleukin-12. The release of these proteins contributes to the antitumor effect of PBMC against MCF-7 breast cancer cells. Based on the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide assay, activated human PBMC showed high cytolytic efficiency towards human breast tumor cells. In summary, NDV was able to stimulate PBMC proliferation, cytokine secretion and cytolytic activity.
Newcastle disease virus; AF2240; immunomodulation; PBMC; breast cancer; immunophenotyping
Feline Infectious Peritonitis (FIP) is a lethal systemic disease, caused by the FIP Virus (FIPV); a virulent mutant of Feline Enteric Coronavirus (FECV). Currently, the viruses virulence determinants and host gene expressions during FIPV infection are not fully understood.
RNA sequencing of Crandell Rees Feline Kidney (CRFK) cells, infected with FIPV strain 79–1146 at 3 hours post infection (h.p.i), were sequenced using the Illumina next generation sequencing approach. Bioinformatic’s analysis, based on Felis catus 2X annotated shotgun reference genome, using CLC bio Genome Workbench mapped both control and infected cell reads to 18899 genes out of 19046 annotated genes. Kal’s Z test statistical analysis was used to analyse the differentially expressed genes from the infected CRFK cells. Real time RT-qPCR was developed for further transcriptional profiling of three genes (PD-1, PD-L1 and A3H) in infected CRFK cells and Peripheral Blood Mononuclear Cells (PBMCs) from healthy and FIP-diseased cats.
Based on Kal’s Z-test, with False Discovery Rate (FDR) <0.05 and >1.99 fold change on gene expressions, a total of 61 genes were differentially expressed by both samples, where 44 genes were up-regulated and the remainder were down-regulated. Most genes were closely clustered together, suggesting a homogeneous expression. The majority of the genes that were significantly regulated, were those associated with monocytes-macrophage and Th1 cell functions, and the regulation of apoptosis. Real time RT-qPCR developed focusing on 2 up-regulated genes (PD-L1 and A3H) together with an apoptosis associated gene PD-1 expressions in FIPV infected CRFK cells and in PBMCs from healthy and FIP diagnosed cats produced concordant results with transcriptome data.
The possible roles of these genes, and their importance in feline coronaviruses infection, are discussed.
FIPV; CRFK; PBMCs; Transcriptome; RT-qPCR; Gene expression; Fold change
Plant-based compounds have been in the spotlight in search of new and promising drugs. Flavokawain A, B and C are naturally occurring chalcones that have been isolated from several medicinal plants; namely the piper methysticum or commercially known as the kava-kava. Multiple researches have been done to evaluate the bioactivities of these compounds. It has been shown that all three flavokawains may hold promising anti-cancer effects. It has also been revealed that both flavokawain A and B are involved in the induction of cell cycle arrest in several cancer cell lines. Nevertheless, flavokawain B was shown to be more effective in treating in vitro cancer cell lines as compared to flavokawain A and C. Flavokawain B also exerts antinociceptive effects as well as anti-inflammation properties. This mini-review attempts to discuss the biological properties of all the flavokawains that have been reported.
Anti-cancer; Anti-inflammation; Apoptosis; Flavokawain; Kava-kava
Bacteriophage EC1-UPM is an N4-like bacteriophage which specifically infects Escherichia coli O78:K80, an avian pathogenic strain that causes colibacillosis in poultry. The complete genome sequence of bacteriophage EC1-UPM was analysed and compared with other closely related N4-like phage groups to assess their genetic similarities and differences.
Bacteriophage EC1-UPM displays a very similar codon usage profile with its host and does not contain any tRNA gene. Comparative genomics analysis reveals close resemblance of bacteriophage EC1-UPM to three N4-like bacteriophages namely vB_EcoP_G7C, IME11 and KBNP21 with a total of 44 protein coding genes shared at 70% identity threshold. The genomic region coding for the tail fiber protein was found to be unique in bacteriophage EC1-UPM. Further annotation of the tail fiber protein using HHpred, a highly sensitive homology detection tool, reveals the presence of protein structure homologous to various polysaccharide processing proteins in its C-terminus. Leveraging on the availability of multiple N4-like bacteriophage genome sequences, the core genes of N4-like bacteriophages were identified and used to perform a multilocus phylogenetic analysis which enabled the construction of a phylogenetic tree with higher confidence than phylogenetic trees based on single genes.
We report for the first time the complete genome sequence of a N4-like bacteriophage which is lytic against avian pathogenic Escherichia coli O78:K80. A novel 928 amino acid residues tail fiber protein was identified in EC1-UPM which may be useful to further the understanding of phage-host specificity. Multilocus phylogenetic analysis using core genes of sequenced N4-like phages showed that the evolutionary relationship correlated well with the pattern of host specificity.
Bacteriophage EC1-UPM; Tail fiber protein; Complete genome; Multilocus phylogenetic analysis
We constructed a novel chicken (Gallus gallus) lung cDNA library fused inside yeast acting domain vector (pGADT7). Using yeast two-hybrid screening with highly pathogenic avian influenza (HPAI) nucleoprotein (NP) from the strain (A/chicken/Malaysia/5858/2004(H5N1)) as bait, and the Gallus gallus lung cDNA library as prey, a novel interaction between the Gallus gallus cellular RNA export adaptor protein Aly/REF and the viral NP was identified. This interaction was confirmed and validated with mammalian two hybrid studies and co-immunoprecipitation assay. Cellular localization studies using confocal microscopy showed that NP and Aly/REF co-localize primarily in the nucleus. Further investigations by mammalian two hybrid studies into the binding of NP of other subtypes of influenza virus such as the swine A/New Jersey/1976/H1N1 and pandemic A/Malaysia/854/2009(H1N1) to human Aly/REF, also showed that the NP of these viruses interacts with human Aly/REF. Our findings are also supported by docking studies which showed tight and favorable binding between H5N1 NP and human Aly/REF, using crystal structures from Protein Data Bank. siRNA knockdown of Aly/REF had little effect on the export of HPAI NP and other viral RNA as it showed no significant reduction in virus titer. However, UAP56, another component of the TREX complex, which recruits Aly/REF to mRNA was found to interact even better with H5N1 NP through molecular docking studies. Both these proteins also co-localizes in the nucleus at early infection similar to Aly/REF. Intriguingly, knockdown of UAP56 in A549 infected cells shows significant reduction in viral titer (close to 10 fold reduction). Conclusively, our study have opened new avenues for research of other cellular RNA export adaptors crucial in aiding viral RNA export such as the SRSF3, 9G8 and ASF/SF2 that may play role in influenza virus RNA nucleocytoplasmic transport.
Newcastle disease virus (NDV) exerts its naturally occurring oncolysis possibly through the induction of apoptosis. We hypothesized that the binding of the virus to the cell via the hemagglutinin-neuraminidase (HN) glycoprotein may be sufficient to not only induce apoptosis but to induce a higher apoptosis level than the parental NDV AF2240 virus. NDV AF2240 induction of apoptosis in MCF-7 human breast cancer cells was analyzed and quantified. In addition, the complete HN gene of NDV strain AF2240 was amplified, sequenced and cloned into the pDisplay eukaryotic expression vector. HN gene expression was first detected at the cell surface membrane of the transfected MCF-7 cells. HN induction of apoptosis in transfected MCF-7 cells was analyzed and quantified. The expression of the HN gene alone was able to induce apoptosis in MCF-7 cells but it was a less potent apoptosis inducer compared to the parental NDV AF2240 strain. In conclusion, the NDV AF2240 strain is a more suitable antitumor candidate agent than its recombinant HN gene unless the latter is further improved by additional modifications.
Newcastle disease virus AF2240; hemagglutinin-neuraminidase glycoprotein; MCF-7; apoptosis
Rhaphidophora korthalsii (Araceae) is a root-climber plant which has been widely used in Chinese traditional medicine for cancer and skin disease treatment. Previous reports have recorded its immunomodulatory effects on mice splenocyte and human peripheral blood. This study investigated the potential immunostimulatory effect of Rhaphidophora korthalsii on human PBMC enriched NK cell.
PBMC was exposed to various concentrations of R. korthalsii extract and the T and NK cell population in the control and extract treated PBMC were identified by immunophenotyping. Intracellular perforin and granzyme B expressions were detected by flow cytometry and extra-cellular Granzyme B, IFN-γ and TNF-α production in the isolated NK cells were determined by ELISA. The cytotoxicity of effector NK cell towards target K562 cell was assessed by CytoTox 96 assay.
Rhaphidophora korthalsii methanol extract significantly increased PBMC NK cell population and intracellular perforin and granzyme B expressions. Moreover, the extract also enhanced the secretion of IFN-γ and TNF-α which subsequently enhanced the cytotoxicity of NK cell against the NK sensitive target K562 cell line. NK cell enriched with extract treated PBMC showed better activation than NK cell directly treated with the extract.
Our findings indicated a potential IL-2 free immunotherapy through direct and indirect R. korthalsii stimulation on NK cell activation.
Rhaphidophora korthalsii; NK cell; Immunomodulation
Germinated brown rice (GBR) is rich in bioactive compounds, which confer GBR with many functional properties. Evidence of its hypocholesterolemic effects is emerging, but the exact mechanisms of action and bioactive compounds involved have not been fully documented. Using type 2 diabetic rats, we studied the effects of white rice, GBR, and brown rice (BR) on lipid profile and on the regulation of selected genes involved in cholesterol metabolism. Our results showed that the upregulation of apolipoprotein A1 and low-density lipoprotein receptor genes was involved in the hypocholesterolemic effects of GBR. Additionally, in vitro studies using HEPG2 cells showed that acylated steryl glycoside, gamma amino butyric acid, and oryzanol and phenolic extracts of GBR contribute to the nutrigenomic regulation of these genes. Transcriptional and nontranscriptional mechanisms are likely involved in the overall hypocholesterolemic effects of GBR suggesting that it may have an impact on the prevention and/or management of hypercholesterolemia due to a wide variety of metabolic perturbations. However, there is need to conduct long-term clinical trials to determine the clinical relevance of the hypocholesterolemic effects of GBR determined through animal studies.