Displaying publications 21 - 40 of 104 in total

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  1. Kamaruzman NI, Aziz NA, Poh CL, Chowdhury EH
    Cancers (Basel), 2019 May 06;11(5).
    PMID: 31064156 DOI: 10.3390/cancers11050632
    Overexpression of oncogenes and cross-talks of the oncoproteins-regulated signaling cascades with other intracellular pathways in breast cancer could lead to massive abnormal signaling with the consequence of tumorigenesis. The ability to identify the genes having vital roles in cancer development would give a promising therapeutics strategy in combating the disease. Genetic manipulations through siRNAs targeting the complementary sequence of the oncogenic mRNA in breast cancer is one of the promising approaches that can be harnessed to develop more efficient treatments for breast cancer. In this review, we highlighted the effects of major signaling pathways stimulated by oncogene products on breast tumorigenesis and discussed the potential therapeutic strategies for targeted delivery of siRNAs with nanoparticles in suppressing the stimulated signaling pathways.
    Matched MeSH terms: RNA, Small Interfering
  2. Lim MN, Lau NS, Chang KM, Leong CF, Zakaria Z
    Singapore Med J, 2007 Oct;48(10):932-8.
    PMID: 17909680
    The multidrug resistance gene, MDR1, is one of the genes responsible for resistance to chemotherapy in the treatment of leukaemia and other cancers. The discovery of RNA interference in mammalian cells has provided a powerful tool to inhibit the expression of this gene. However, very little is known about the transfection of leukaemia cells with short interfering RNA (siRNA) targeted at MDR1. This study aims to evaluate the effectiveness of two chemically-synthesised siRNA in modulating MDR1 gene and inhibiting P-glycoprotein expression in leukaemic cells. We also evaluated two siRNA delivery methods in this study.
    Matched MeSH terms: RNA, Small Interfering/administration & dosage; RNA, Small Interfering/genetics; RNA, Small Interfering/pharmacology*
  3. Teoh HK, Chong PP, Abdullah M, Sekawi Z, Tan GC, Leong CF, et al.
    Leuk. Res., 2016 Jan;40:44-53.
    PMID: 26626206 DOI: 10.1016/j.leukres.2015.10.004
    Studies demonstrated that mesenchymal stromal cells (MSC) from bone marrow stroma produced high concentration of interleukin-6 (IL-6) that promoted multiple myeloma cell growth. In view of the failure of IL-6 monoclonal antibody therapy to demonstrate substantial clinical responses in early clinical trials, more effective methods are needed in order to disrupt the favourable microenvironment provided by the bone marrow stroma. In this study, we evaluated the short interfering RNA (siRNA)-mediated silencing of IL-6 in MSC and the efficacy of these genetically modified MSC, with IL-6 suppression, on inhibition of U266 multiple myeloma cell growth. IL-6 mRNA and protein were significantly suppressed by 72h post IL-6 siRNA transfection without affecting the biological properties of MSC. Here we show significant inhibition of cell growth and IL-6 production in U266 cells co-cultured with MSC transfected with IL-6 siRNA when compared to U266 cells co-cultured with control MSC. We also show that the tumour volume and mitotic index of tumours in nude mice co-injected with U266 and MSC transfected with IL-6 siRNA were significantly reduced compared to tumours of mice co-injected with control MSC. Our results suggest potential use of RNA interference mediated therapy for multiple myeloma.
    Matched MeSH terms: RNA, Small Interfering/genetics*
  4. Amjad MW, Mohd Amin MC, Mahali SM, Katas H, Ismail I, Hassan MN, et al.
    PLoS One, 2014;9(8):e105234.
    PMID: 25133390 DOI: 10.1371/journal.pone.0105234
    Biomolecules have been widely investigated as potential therapeutics for various diseases. However their use is limited due to rapid degradation and poor cellular uptake in vitro and in vivo. To address this issue, we synthesized a new nano-carrier system comprising of cholic acid-polyethylenimine (CA-PEI) copolymer micelles, via carbodiimide-mediated coupling for the efficient delivery of small interfering ribonucleic acid (siRNA) and bovine serum albumin (BSA) as model protein. The mean particle size of siRNA- or BSA-loaded CA-PEI micelles ranged from 100-150 nm, with zeta potentials of +3-+11 mV, respectively. Atomic force, transmission electron and field emission scanning electron microscopy demonstrated that the micelles exhibited excellent spherical morphology. No significant morphology or size changes were observed in the CA-PEI micelles after siRNA and BSA loading. CA-PEI micelles exhibited sustained release profile, the effective diffusion coefficients were successfully estimated using a mathematically-derived cylindrical diffusion model and the release data of siRNA and BSA closely fitted into this model. High siRNA and BSA binding and loading efficiencies (95% and 70%, respectively) were observed for CA-PEI micelles. Stability studies demonstrated that siRNA and BSA integrity was maintained after loading and release. The CA-PEI micelles were non cytotoxic to V79 and DLD-1 cells, as shown by alamarBlue and LIVE/DEAD cell viability assays. RT-PCR study revealed that siRNA-loaded CA-PEI micelles suppressed the mRNA for ABCB1 gene. These results revealed the promising potential of CA-PEI micelles as a stable, safe, and versatile nano-carrier for siRNA and the model protein delivery.
    Matched MeSH terms: RNA, Small Interfering/chemistry
  5. Tekade RK, Maheshwari RG, Sharma PA, Tekade M, Chauhan AS
    Curr Pharm Des, 2015;21(31):4614-36.
    PMID: 26486147
    siRNA technology presents a helpful means of gene silencing in mammalian cells. Advancement in the field includes enhanced attentiveness in the characterization of target and off-target effects employing suitable controls and gene expression microarrays. These will permit expansion in the measurement of single and multiple target combinations and also permit comprehensive efforts to understand mammalian cell processes. Another fact is that the delivery of siRNA requires the creation of a nanoparticulate vector with controlled structural geometry and surface modalities inside the targeted cells. On the other hand, dendrimers represent the class of carrier system where massive control over size, shape and physicochemical properties makes this delivery vector exceptional and favorable in genetic transfection applications. The siRNA therapeutics may be incorporated inside the geometry of the density controlled dendrimers with the option of engineering the structure to the specific needs of the genetic material and its indication. The existing reports on the siRNA carrying and deliverance potential of dendrimers clearly suggest the significance of this novel class of polymeric architecture and certainly elevate the futuristic use of this highly branched vector as genetic material delivery system.
    Matched MeSH terms: RNA, Small Interfering/administration & dosage*
  6. Citartan M, Kaur H, Presela R, Tang TH
    Int J Pharm, 2019 Aug 15;567:118483.
    PMID: 31260780 DOI: 10.1016/j.ijpharm.2019.118483
    Aptamers, nucleic acid ligands that are specific against their corresponding targets are increasingly employed in a variety of applications including diagnostics and therapeutics. The specificity of the aptamers against their targets is also used as the basis for the formulation of the aptamer-based drug delivery system. In this review, we aim to provide an overview on the chaperoning roles of aptamers in acting as the cargo or load carriers, delivering contents to the targeted sites via cell surface receptors. Internalization of the aptamer-biomolecule conjugates via receptor-mediated endocytosis and the strategies to augment the rate of endocytosis are underscored. The cargos chaperoned by aptamers, ranging from siRNAs to DNA origami are illuminated. Possible impediments to the aptamer-based drug deliveries such as susceptibility to nuclease resistance, potentiality for immunogenicity activation, tumor heterogeneity are speculated and the corresponding amendment strategies to address these shortcomings are discussed. We prophesy that the future of the aptamer-based drug delivery will take a trajectory towards DNA nanorobot-based assay.
    Matched MeSH terms: RNA, Small Interfering/administration & dosage
  7. Katas H, Abdul Ghafoor Raja M, Ee LC
    Drug Dev Ind Pharm, 2014 Nov;40(11):1443-50.
    PMID: 23962166 DOI: 10.3109/03639045.2013.828222
    Recently, a newly discovered Dicer-substrate siRNA (DsiRNA) demonstrates higher potency in gene silencing than siRNA but both suffer from rapid degradation, poor cellular uptake and chemical instability. Therefore, Tat-peptide was exploited to protect and facilitate their delivery into cells. In this study, Tat-peptide was complexed with siRNA or DsiRNA through simple complexation. The physicochemical properties (particle size, surface charge and morphology) of the complexes formed were then characterized. The ability of Tat-peptide to carry and protect siRNA or DsiRNA was determined by UV-Vis spectrophotometry and serum protection assay, respectively. Cytotoxicity effect of these complexes was assessed in V79 cell line. siRNA-Tat complexes had particle size ranged from 186 ± 17.8 to 375 ± 8.3 nm with surface charge ranged from -9.3 ± 1.0 to +13.5 ± 1.0 mV, depending on the Tat-to-siRNA concentration ratio. As for DsiRNA-Tat complexes, the particle size was smaller than the ones complexed with siRNA, ranging from 176 ± 8.6 to 458 ± 14.7 nm. Their surface charge was in the range of +27.1 ± 3.6 to +38.1 ± 0.9 mV. Both oligonucleotide (ON) species bound strongly to Tat-peptide, forming stable complexes with loading efficiency of more than 86%. These complexes were relatively non cytotoxic as the cell viability of ∼90% was achieved. In conclusion, Tat-peptide has a great potential as siRNA and DsiRNA vector due to the formation of stable complexes with desirable physical characteristics, low toxicity and able to carry high amount of siRNA or DsiRNA.
    Matched MeSH terms: RNA, Small Interfering/administration & dosage*
  8. Katas H, Wen CY, Siddique MI, Hussain Z, Mohd Fadhil FH
    Ther Deliv, 2017 01;8(3):137-150.
    PMID: 28145827 DOI: 10.4155/tde-2016-0075
    AIM: Chitosan (CS) has been extensively studied as drug delivery systems for wound healing. Results/methodology: CS nanoparticles were loaded with curcumin (Cur) and DsiRNA against prostaglandin transporter gene and they were incorporated into 20 and 25% w/v Pluronic F-127. The gels were later analyzed for their rheology, gelation temperature (Tgel), morphology, drug incorporation and in vitro drug release. The particle size was in the range of 231 ± 17-320 ± 20 nm, depending on CS concentration. The gels had Tgel of 23-28°C and exhibited sustained drug release with high accumulated amount of drugs over 48 h.

    CONCLUSION: A thermo-sensitive gel containing Cur/DsiRNA CS nanoparticles was successfully developed and has a great potential to be further developed.

    Matched MeSH terms: RNA, Small Interfering/chemistry*
  9. Che Mat MF, Abdul Murad NA, Ibrahim K, Mohd Mokhtar N, Wan Ngah WZ, Harun R, et al.
    Int J Oncol, 2016 Dec;49(6):2359-2366.
    PMID: 27840905 DOI: 10.3892/ijo.2016.3755
    Glioblastoma multiforme (GBM) is an aggressive brain tumor and most patients have poor prognosis. Despite many advances in research, there has been no significant improvement in the patient survival rate. New molecular therapies are being studied and RNA interference (RNAi) therapy is one of the promising approaches to improve prognosis and increase survival in patients with GBM. We performed a meta‑analysis of five different microarray datasets and identified 460 significantly upregulated genes in GBM. Loss‑of‑function screening of these upregulated genes using LN18 cells was performed to identify the significant target genes for glioma. Further investigations were performed using siRNA in LN18 cells and various functional assays were carried out on the selected candidate gene to understand further its role in GBM. We identified PROS1 as a candidate gene for GBM from the meta‑analysis and RNAi screening. Knockdown of PROS1 in LN18 cells significantly induced apoptosis compared to siPROS1‑untreated cells (p<0.05). Migration in cells treated with siPROS1 was reduced significantly (p<0.05) and this was confirmed with wound-healing assay. PROS1 knockdown showed substantial reduction in cell invasion up to 82% (p<0.01). In addition, inhibition of PROS1 leads to decrease in cellular proliferation by 18%. Knockdown of PROS1 in LN18 cells caused activation of both of the extrinsic and intrinsic apoptotic pathways. It caused major upregulation of FasL which is important for death receptor signaling activation and also downregulation of GAS6 and other members of TAM family of receptors. PROS1 may play an important role in the development of GBM through cellular proliferation, migration and invasion as well as apoptosis. Targeting PROS1 in GBM could be a novel therapeutic strategy in GBM treatment.
    Matched MeSH terms: RNA, Small Interfering/genetics; RNA, Small Interfering/therapeutic use
  10. Hussain Z, Katas H, Yan SL, Jamaludin D
    Curr Drug Deliv, 2017;14(7):1016-1027.
    PMID: 28240178 DOI: 10.2174/1567201814666170224142446
    BACKGROUND: Despite having excellent anticancer efficacy and ability to knockdown gene expression, the therapeutic feasibility of Dicer-substrate small interfering RNA (DsiRNA) is limited due to its poor cellular uptake, chemical instability and rapid degradation in biological environments.

    OBJECTIVE: The present study was aimed to circumvent the pharmaceutical issues related to DsiRNA delivery to colon for the treatment of colorectal cancer.

    METHOD: In this study, we have prepared water-soluble chitosan (WSC)-DsiRNA complex nanoparticles (NPs) by a simple complexation method and subsequently coated with pectin to protect DsiRNA from gastric milieu.

    RESULTS: The mean particle size and zeta potential of the prepared WSC-DsiRNA complexes were varied from 145 ± 4 nm to 867 ± 81 nm and +38 ± 4 to -6.2 ± 2.7 mV respectively, when the concentrations of WSC (0.1%, 0.2% and 0.3% w/v) and pectin (0.1%, 0.2% and 0.25% w/v) were varied. The electron microscopic analysis revealed that morphology of WSC-DsiRNA complexes was varied from smooth spherical to irregular spherical. Cytotoxicity analysis demonstrated that viability of colorectal adenocarcinoma cell was decreased when the dose of WSC-DsiRNA was increased over the incubation from 24 to 48 h. A significantly low cumulative release of DsiRNA in simulated gastric (<15%) and intestinal fluids (<30%) and a marked increase in its release (>90%) in simulated colonic fluid (SCF) evidenced the feasibility and suitability of WSC-DsiRNA complexes for the colonic delivery.

    CONCLUSION: These findings clearly indicated promising potential of WSC-DsiRNA complexes as a carrier to delivery DsiRNA to colon for the treatment of colorectal cancer.

    Matched MeSH terms: RNA, Small Interfering/administration & dosage*; RNA, Small Interfering/chemistry
  11. Li YT, Chua MJ, Kunnath AP, Chowdhury EH
    Int J Nanomedicine, 2012;7:2473-81.
    PMID: 22701315 DOI: 10.2147/IJN.S30500
    Multidrug resistance, a major impediment to successful cancer chemotherapy, is the result of overexpression of ATP-binding cassette (ABC) transporters extruding internalized drugs. Silencing of ABC transporter gene expression with small interfering RNA (siRNA) could be an attractive approach to overcome multidrug resistance of cancer, although delivery of siRNA remains a major hurdle to fully exploit the potential of siRNA-based therapeutics. Recently, we have developed pH-sensitive carbonate apatite nanoparticles to efficiently carry and transport siRNA across the cell membrane, enabling knockdown of the cyclin B1 gene and consequential induction of apoptosis in synergy with anti-cancer drugs.
    Matched MeSH terms: RNA, Small Interfering/administration & dosage*; RNA, Small Interfering/genetics; RNA, Small Interfering/pharmacokinetics
  12. Thou EMH, Choo QC, Chew CH
    Eur. Cytokine Netw., 2020 Jun 01;31(2):59-67.
    PMID: 32933893 DOI: 10.1684/ecn.2020.0446
    Atherosclerosis is initiated when lipoproteins are trapped by proteoglycans in the arterial intima. Macrophages play a vital role in this disease, especially in the formation of foam cells and the regulation of pro-inflammatory responses. They also participate in plaque stabilization through the secretion of matrix metalloproteinases. Studies have reported the role of ADAMTS proteases in osteoarthritis and atherosclerotic lesions.In the present study, we have studied the effect of interleukin-17A (IL-17A) on the expression of ADAMTS-5 in the macrophage cell line THP-1. The results show that the mRNA and protein expression levels of ADAMTS-5 were significantly upregulated when differentiated THP-1 cells were treated with 100 ng/mL of IL-17A for 24 h with maximum ADAMTS-5 mRNA expression levels obtained at 8 h of stimulation. Subsequent inhibition studies showed that IL-17A upregulation of ADAMTS-5 was mediated through ERK and JNK pathways in THP-1 cells. Phosphorylation studies revealed that the expression of ADAMTS-5 transcripts was upregulated by IL-17A through the activation of p-c-Raf (S338), p-MEK1/2 (Ser217/221), p-p44/42 MAPK (Thr202/Tyr204), and p-Elk1 (Ser383). ERK1/2 siRNA transfection further confirmed that the ERK pathway is involved in the expression of ADAMTS-5 in IL-17A-stimulated THP-1 cells.
    Matched MeSH terms: RNA, Small Interfering
  13. Yıldırım-Buharalıoğlu G, Bond M, Sala-Newby GB, Hindmarch CC, Newby AC
    Front Immunol, 2017;8:92.
    PMID: 28228757 DOI: 10.3389/fimmu.2017.00092
    BACKGROUND: Interferon-γ (IFN-γ) or interleukin-4 (IL-4) drives widely different transcriptional programs in macrophages. However, how IFN-γ and IL-4 alter expression of histone-modifying enzymes involved in epigenetic regulation and how this affects the resulting phenotypic polarization is incompletely understood.

    METHODS AND RESULTS: We investigated steady-state messenger RNA levels of 84 histone-modifying enzymes and related regulators in colony-stimulating factor-1 differentiated primary human macrophages using quantitative polymerase chain reaction. IFN-γ or IL-4 treatment for 6-48 h changed 11 mRNAs significantly. IFN-γ increased CIITA, KDM6B, and NCOA1, and IL-4 also increased KDM6B by 6 h. However, either cytokine decreased AURKB, ESCO2, SETD6, SUV39H1, and WHSC1, whereas IFN-γ alone decreased KAT2A, PRMT7, and SMYD3 mRNAs only after 18 h, which coincided with decreased cell proliferation. Rendering macrophages quiescent by growth factor starvation or adenovirus-mediated overexpression of p27(kip1) inhibited expression of AURKB, ESCO2, SUV39H1, and WHSC1, and mRNA levels were restored by overexpressing the S-phase transcription factor E2F1, implying their expression, at least partly, depended on proliferation. However, CIITA, KDM6B, NCOA1, KAT2A, PRMT7, SETD6, and SMYD3 were regulated independently of effects on proliferation. Silencing KDM6B, the only transcriptional activator upregulated by both IFN-γ and IL-4, pharmacologically or with short hairpin RNA, blunted a subset of responses to each cytokine.

    CONCLUSION: These findings demonstrate that IFN-γ or IL-4 can regulate the expression of histone acetyl transferases and histone methyl transferases independently of effects on proliferation and that upregulation of the histone demethylase, KDM6B, assists phenotypic polarization by both cytokines.

    Matched MeSH terms: RNA, Small Interfering
  14. Khor ES, Wong PF
    Int J Biochem Cell Biol, 2018 Aug;101:64-73.
    PMID: 29857052 DOI: 10.1016/j.biocel.2018.05.016
    Accumulation of senescent endothelial cells can contribute to endothelium dysfunction. Suppression of MTOR signaling has been shown to delay senescence but the mechanism that underpins this effect, particularly one that involves miRNAs, remains to be further defined. This study sought to identify miRNAs involved in MTORC1-mediated inhibition of replicative senescence in endothelial cells. Pre-senescent HUVECs were prolonged treated with low dose rapamycin (1 nM), an MTOR inhibitor. Rapamycin treatment down-regulated the phosphorylated MTOR, RPS6 and 4EBP1 expressions, which confirmed MTORC1 suppression. Prolonged low dose rapamycin treatment has significantly reduced the percentage of senescence-associated beta galactosidase (SA-β gal) positively stained senescent cells and P16INK4A expression in these cells. On the contrary, the percentage of BrdU-labelled proliferating cells has significantly increased. RPTOR, a positive regulator of MTORC1 was knockdown using RPTOR siRNA to inhibit MTORC1 activation. RPTOR knockdown was evidenced by significant suppressions of RPTOR mRNA and protein expression levels. In these cells, the expression of miR-107 was down-regulated whereas miR-145-5p and miR-217 were up-regulated. Target gene prediction revealed PTEN as the target of miR-107 and this was confirmed by biotin pull-down assay. Over-expression of miR-107 has decreased PTEN expression, increased MTORC1 activity, induced cell cycle arrest at G0/G1 phase and up-regulated P16INK4A expression but mitigated tube formation. Collectively, our findings revealed that delayed endothelial replicative senescence caused by the inhibition of MTORC1 activation could be modulated by miR-107 via its influence on PTEN.
    Matched MeSH terms: RNA, Small Interfering
  15. Jaafar F, Abdullah A, Makpol S
    Sci Rep, 2018 Jul 11;8(1):10471.
    PMID: 29992988 DOI: 10.1038/s41598-018-28708-z
    Tocotrienol-rich fraction (TRF) is palm vitamin E that consists of tocopherol and tocotrienol. TRF is involved in important cellular regulation including delaying cellular senescence. A key regulator of cellular senescence, Sirtuin 1 (SIRT1) is involved in lipid metabolism. Thus, SIRT1 may regulate vitamin E transportation and bioavailability at cellular level. This study aimed to determine the role of SIRT1 on cellular uptake and bioavailability of TRF in human diploid fibroblasts (HDFs). SIRT1 gene in young HDFs was silenced by small interference RNA (siRNA) while SIRT1 activity was inhibited by sirtinol. TRF treatment was given for 24 h before or after SIRT1 inhibition. Cellular concentration of TRF isomers was determined according to the time points of before and after TRF treatment at 0, 24, 48, 72 and 96 h. Our results showed that all tocotrienol isomers were significantly taken up by HDFs after 24 h of TRF treatment and decreased 24 h after TRF treatment was terminated but remained in the cell up to 72 h. The uptake of α-tocopherol, α-tocotrienol and β-tocotrienol was significantly higher in senescent cells as compared to young HDFs indicating higher requirement for vitamin E in senescent cells. Inhibition of SIRT1 gene increased the uptake of all tocotrienol isomers but not α-tocopherol. However, SIRT1 inhibition at protein level decreased tocotrienol concentration. In conclusion, SIRT1 may regulate the cellular uptake and bioavailability of tocotrienol isomers in human diploid fibroblast cells while a similar regulation was not shown for α-tocopherol.
    Matched MeSH terms: RNA, Small Interfering
  16. Dua K, Wadhwa R, Singhvi G, Rapalli V, Shukla SD, Shastri MD, et al.
    Drug Dev Res, 2019 09;80(6):714-730.
    PMID: 31691339 DOI: 10.1002/ddr.21571
    Lung diseases are the leading cause of mortality worldwide. The currently available therapies are not sufficient, leading to the urgent need for new therapies with sustained anti-inflammatory effects. Small/short or silencing interfering RNA (siRNA) has potential therapeutic implications through post-transcriptional downregulation of the target gene expression. siRNA is essential in gene regulation, so is more favorable over other gene therapies due to its small size, high specificity, potency, and no or low immune response. In chronic respiratory diseases, local and targeted delivery of siRNA is achieved via inhalation. The effectual delivery can be attained by the generation of aerosols via inhalers and nebulizers, which overcomes anatomical barriers, alveolar macrophage clearance and mucociliary clearance. In this review, we discuss the different siRNA nanocarrier systems for chronic respiratory diseases, for safe and effective delivery. siRNA mediated pro-inflammatory gene or miRNA targeting approach can be a useful approach in combating chronic respiratory inflammatory conditions and thus providing sustained drug delivery, reduced therapeutic dose, and improved patient compliance. This review will be of high relevance to the formulation, biological and translational scientists working in the area of respiratory diseases.
    Matched MeSH terms: RNA, Small Interfering
  17. Loh CY, Arya A, Naema AF, Wong WF, Sethi G, Looi CY
    Front Oncol, 2019;9:48.
    PMID: 30847297 DOI: 10.3389/fonc.2019.00048
    Signal Transducer and Activator of Transcription (STAT) pathway is connected upstream with Janus kinases (JAK) family protein and capable of integrating inputs from different signaling pathways. Each family member plays unique functions in signal transduction and crucial in mediating cellular responses to different kind of cytokines. STAT family members notably STAT3 and STAT5 have been involved in cancer progression whereas STAT1 plays opposite role by suppressing tumor growth. Persistent STAT3/5 activation is known to promote chronic inflammation, which increases susceptibility of healthy cells to carcinogenesis. Here, we review the role of STATs in cancers and inflammation while discussing current therapeutic implications in different cancers and test models, especially the delivery of STAT3/5 targeting siRNA using nanoparticulate delivery system.
    Matched MeSH terms: RNA, Small Interfering
  18. Rahman NIA, Abdul Murad NA, Mollah MM, Jamal R, Harun R
    Front Pharmacol, 2017;8:540.
    PMID: 28871224 DOI: 10.3389/fphar.2017.00540
    About 40% of lung cancer cases globally are diagnosed at the advanced stage. Lung cancer has a high mortality and overall survival in stage I disease is only 70%. This study was aimed at finding a candidate of transcription regulator that initiates the mechanism for metastasis by integrating computational and functional studies. The genes involved in lung cancer were retrieved using in silico software. 10 kb promoter sequences upstream were scanned for the master regulator. Transient transfection of shRNA NFIXs were conducted against A549 and NCI-H1299 cell lines. qRT-PCR and functional assays for cell proliferation, migration and invasion were carried out to validate the involvement of NFIX in metastasis. Genome-wide gene expression microarray using a HumanHT-12v4.0 Expression BeadChip Kit was performed to identify differentially expressed genes and construct a new regulatory network. The in silico analysis identified NFIX as a master regulator and is strongly associated with 17 genes involved in the migration and invasion pathways including IL6ST, TIMP1 and ITGB1. Silencing of NFIX showed reduced expression of IL6ST, TIMP1 and ITGB1 as well as the cellular proliferation, migration and invasion processes. The data was integrated with the in silico analyses to find the differentially expressed genes. Microarray analysis showed that 18 genes were expressed differentially in both cell lines after statistical analyses integration between t-test, LIMMA and ANOVA with Benjamini-Hochberg adjustment at p-value < 0.05. A transcriptional regulatory network was created using all 18 genes, the existing regulated genes including the new genes PTCH1, NFAT5 and GGCX that were found highly associated with NFIX, the master regulator of metastasis. This study suggests that NFIX is a promising target for therapeutic intervention that is expected to inhibit metastatic recurrence and improve survival rate.
    Matched MeSH terms: RNA, Small Interfering
  19. Dua K, Chellappan DK, Singhvi G, de Jesus Andreoli Pinto T, Gupta G, Hansbro PM
    Panminerva Med, 2018 Dec;60(4):230-231.
    PMID: 30563304 DOI: 10.23736/S0031-0808.18.03459-6
    Matched MeSH terms: RNA, Small Interfering/metabolism
  20. Thomas W, Dooley R, Quinn S, Robles MY, Harvey BJ
    Steroids, 2020 03;155:108553.
    PMID: 31836481 DOI: 10.1016/j.steroids.2019.108553
    Protein kinase D2 (PKD2) is a serine/threonine protein kinase which plays an important role in vesicle fission at the trans-Golgi network (TGN) to coordinate subcellular trafficking with gene expression. We found that in the rat kidney, PKD2 is specifically expressed in collecting duct principal cells predominantly at the apical membrane and with lower basal expression in cytosolic compartments. When rats were maintained on a Na+ depleted diet (<0.87 mmol Na+/kg) to increase plasma aldosterone levels, PKD2 became internalized to a cytoplasmic compartment. Treatment of murine M1 cortical collecting duct (M1-CCD) cells with aldosterone (10 nM) promoted PKD2 co-localization with the trans-Golgi network within 30 min. PKD2 underwent autophosphorylation at Ser876 within 10 min of aldosterone treatment and remained phosphorylated (active) for at least 24 h. A stable PKD2 shRNA knock-down (PKD2 KD) M1-CCD cell line was developed to study the role of PKD2 in epithelial Na+ channel (ENaC) trafficking and transepithelial Na+ transport (SCC) in epithelial monolayers grown in Ussing chambers. The PKD2 KD cells developed transepithelial resistance with kinetics equivalent to wild-type cells, however the transepithelial voltage and Na+ current were significantly elevated in PKD2 knock-down CCD epithelia. The higher basal SCC was due to increased ENaC activity. Aldosterone treatment for 24 h resulted in a decline in ENaC activity in the PKD2 KD cells as opposed to the increase observed in the wild-type cells. The paradoxical inhibition of SCC by aldosterone in PKD2 KD epithelium was attributed to a reduction in ENaC current and lower membrane abundance of ENaC, demonstrating that PKD2 plays a critical tonic role in ENaC trafficking and channel subunit stability. The rapid activation of PKD2 by aldosterone is synergistic with the transcriptional activity of MR and contributes to increased ENaC activity.
    Matched MeSH terms: RNA, Small Interfering/pharmacology
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