Displaying publications 301 - 320 of 352 in total

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  1. Synthesis, structure, DNA/BSA interaction and in vitro cytotoxic activity of nickel(II) complexes derived from S-allyldithiocarbazate
    Nanjundan N, Selvakumar P, Narayanasamy R, Haque RA, Velmurugan K, Nandhakumar R, et al.
    J. Photochem. Photobiol. B, Biol., 2014 Dec;141:176-85.
    PMID: 25463665 DOI: 10.1016/j.jphotobiol.2014.10.009
    Two nickel(II) complexes with formula NiL1 and NiL2 (HL1 = S-allyl-4-methoxybenzylidene hydrazinecarbodithioate, HL2 = S-allyl-1-napthylidenehydrazinecarbodithioate) have been synthesized and characterized by elemental analysis, FT-IR, NMR, UV-vis spectroscopy and ESI mass spectrometry. The crystal structure of complex 1 has been determined by single crystal X-ray diffractometry. Both HL1 and HL2 ligands are coordinated to the metal in thiolate form. In complexes, squareplanar geometry of the nickel is coordinated with two bidentate ligand units acting through azomethine nitrogen and thiolato sulfur atoms. To explore the potential medicinal value of the complexes with calf thymus DNA and bovine serum albumin (BSA) were studied at normal physiological conditions using fluorescence spectral techniques. The DNA binding constant values of the complexes were found in the range from 5.02 × 10(4), 3.54 × 10(4), and the binding affinities are in the following order 1 > 2. In addition, nickel complexes 1 and 2 shows better binding propensity to the bovine serum albumin (BSA) protein, giving a Ksv value 5.8 × 10(4), 4.47 × 10(4) respectively. From the oxidative cleavage of the complexes with pBR322 DNA, it is inferred that the effects of cleavage are dose-dependent. In addition, in vitro cytotoxicity of the complexes assayed against Vero and HeLa cell lines have shown higher cytotoxic activity with the lower IC50 values indicating their efficiency in killing cancer cells even at various concentrations.
    Matched MeSH terms: Spectrometry, Fluorescence
  2. Fulltext Cytotoxic constituents from the rhizomes of Curcuma zedoaria
    Ahmed Hamdi OA, Syed Abdul Rahman SN, Awang K, Abdul Wahab N, Looi CY, Thomas NF, et al.
    ScientificWorldJournal, 2014;2014:321943.
    PMID: 25126594 DOI: 10.1155/2014/321943
    Curcuma zedoaria also known as Temu putih is traditionally used in food preparations and treatment of various ailments including cancer. The cytotoxic activity of hexane, dichloromethane, ethyl acetate, methanol, and the methanol-soxhlet extracts of Curcuma zedoaria rhizomes was tested on two human cancer cell lines (Ca Ski and MCF-7) and a noncancer cell line (HUVEC) using MTT assay. Investigation on the chemical components in the hexane and dichloromethane fractions gave 19 compounds, namely, labda-8(17),12 diene-15,16 dial (1), dehydrocurdione (2), curcumenone (3), comosone II (4), curcumenol (5), procurcumenol (6), germacrone (7), zerumbone epoxide (8), zederone (9), 9-isopropylidene-2,6-dimethyl-11-oxatricyclo[6.2.1.0(1,5)]undec-6-en-8-ol (10), furanodiene (11), germacrone-4,5-epoxide (12), calcaratarin A (13), isoprocurcumenol (14), germacrone-1,10-epoxide (15), zerumin A (16), curcumanolide A (17), curcuzedoalide (18), and gweicurculactone (19). Compounds (1-19) were evaluated for their antiproliferative effect using MTT assay against four cancer cell lines (Ca Ski, MCF-7, PC-3, and HT-29). Curcumenone (3) and curcumenol (5) displayed strong antiproliferative activity (IC50 = 8.3 ± 1.0 and 9.3 ± 0.3 μg/mL, resp.) and were found to induce apoptotic cell death on MCF-7 cells using phase contrast and Hoechst 33342/PI double-staining assay. Thus, the present study provides basis for the ethnomedical application of Curcuma zedoaria in the treatment of breast cancer.
    Matched MeSH terms: Microscopy, Fluorescence
  3. Low level of TERC gene amplification between chronic myeloid leukaemia patients resistant and respond to imatinib mesylate treatment
    Mohamad Ashari ZS, Sulong S, Hassan R, Husin A, Sim GA, Abdul Wahid SF
    Asian Pac J Cancer Prev, 2014;15(4):1863-9.
    PMID: 24641422
    The amplification of telomerase component (TERC) gene could play an important role in generation and treatment of haematological malignancies. This present study was aimed to investigate copy number amplification status of TERC gene in chronic myeloid leukaemia (CML) patients who were being treated with imatinib mesylate (IM). Genomic DNA was extracted from peripheral blood of CML-IM Resistant (n=63), CML-IM Respond (n=63) and healthy individuals (n=30). TERC gene copy number predicted (CNP) and copy number calculated (CNC) were determined based on Taqman® Copy Number Assay. Fluorescence in situ hybridization (FISH) analysis was performed to confirm the normal signal pattern in C4 (calibrator) for TERC gene. Nine of CML patients showed TERC gene amplification (CNP=3), others had 2 CNP. A total of 17 CML patients expressed CNC>2.31 and the rest had 2.31>CNC>1.5. TERC gene CNP value in healthy individuals was 2 and their CNC value showed in range 1.59-2.31. The average CNC TERC gene copy number was 2.07, 1.99 and 1.94 in CML- IM Resistant patients, CML-IM Respond and healthy groups, respectively. No significant difference of TERC gene amplification observed between CML-IM Resistant and CML-IM Respond patients. Low levels of TERC gene amplification might not have a huge impact in haematological disorders especially in terms of resistance towards IM treatment.
    Matched MeSH terms: In Situ Hybridization, Fluorescence
  4. Synthesis of isatin thiosemicarbazones derivatives: in vitro anti-cancer, DNA binding and cleavage activities
    Ali AQ, Teoh SG, Salhin A, Eltayeb NE, Khadeer Ahamed MB, Abdul Majid AM
    Spectrochim Acta A Mol Biomol Spectrosc, 2014 May 5;125:440-8.
    PMID: 24607427 DOI: 10.1016/j.saa.2014.01.086
    New derivatives of thiosemicarbazone Schiff base with isatin moiety were synthesized L1-L6. The structures of these compounds were characterized based on the spectroscopic techniques. Compound L6 was further characterized by XRD single crystal. The interaction of these compounds with calf thymus (CT-DNA) exhibited high intrinsic binding constant (k(b)=5.03-33.00×10(5) M(-1)) for L1-L3 and L5 and (6.14-9.47×10(4) M(-1)) for L4 and L6 which reflect intercalative activity of these compounds toward CT-DNA. This result was also confirmed by the viscosity data. The electrophoresis studies reveal the higher cleavage activity of L1-L3 than L4-L6. The in vitro anti-proliferative activity of these compounds against human colon cancer cell line (HCT 116) revealed that the synthesized compounds (L3, L6 and L2) exhibited good anticancer potency.
    Matched MeSH terms: Spectrometry, Fluorescence
  5. Fulltext Performance of a cyanobacteria whole cell-based fluorescence biosensor for heavy metal and pesticide detection
    Shing WL, Heng LY, Surif S
    Sensors (Basel), 2013;13(5):6394-404.
    PMID: 23673679 DOI: 10.3390/s130506394
    Whole cell biosensors always face the challenge of low stability of biological components and short storage life. This paper reports the effects of poly(2-hydroxyethyl methacrylate) (pHEMA) immobilization on a whole cell fluorescence biosensor for the detection of heavy metals (Cu, Pb, Cd), and pesticides (dichlorophenoxyacetic acid (2,4-D), and chlorpyrifos). The biosensor was produced by entrapping the cyanobacterium Anabaena torulosa on a cellulose membrane, followed by applying a layer of pHEMA, and attaching it to a well. The well was then fixed to an optical probe which was connected to a fluorescence spectrophotometer and an electronic reader. The optimization of the biosensor using several factors such as amount of HEMA and drying temperature were undertaken. The detection limits of biosensor without pHEMA for Cu, Cd, Pb, 2,4-D and chlorpyrifos were 1.195, 0.027, 0.0100, 0.025 and 0.025 µg/L respectively. The presence of pHEMA increased the limits of detection to 1.410, 0.250, 0.500, 0.235 and 0.117 µg/L respectively. pHEMA is known to enhance the reproducibility of the biosensor with average relative standard deviation (RSD) of ±1.76% for all the pollutants tested, 48% better than the biosensor without pHEMA (RSD = ±3.73%). In storability test with Cu 5 µg/L, the biosensor with pHEMA performed 11.5% better than the test without pHEMA on day-10 and 5.2% better on day-25. pHEMA is therefore a good candidate to be used in whole cell biosensors as it increases reproducibility and enhances biosensor storability.
    Matched MeSH terms: Fluorescence
  6. Cyclin D1 amplification in tongue and cheek squamous cell carcinoma
    Mahdey HM, Ramanathan A, Ismail SM, Abraham MT, Jamaluddin M, Zain RB
    Asian Pac J Cancer Prev, 2011;12(9):2199-204.
    PMID: 22296356
    INTRODUCTION: Several molecular markers have been studied for their usefulness as prognostic markers in oral squamous cell carcinoma (OSCC). One such molecular marker is cyclin D1 which is a proto-oncogene located on 11q13 in humans.

    OBJECTIVE: To explore the feasibility of using cyclin D1 as a prognostic marker in tongue and cheek SCC by the fluorescent-in-situ hybridization (FISH) method.

    METHODS: Fifty paraffin-embedded samples (25 each of cheek and tongue SCCs) were obtained from the archives of the Oral Pathology Diagnostic Laboratory. Sociodemographic data, histopathologic diagnoses, lymph node status and survival data were obtained from the Malaysian Oral Cancer Database and Tissue Bank System (MOCDTBS)coordinated by the Oral Cancer Research and Coordinating Centre (OCRCC), University of Malaya. The FISH technique was used to detect the amplification of cyclin D1 using the Vysis protocol. Statistical correlations of cyclin D1 with site and lymph node status were analyzed using the Fisher exact test. Kaplan-Meier and Log Rank (Mantel-Cox) test were used to analyze cyclin D1 amplification and median survival time.

    RESULTS: Positive amplification of cyclin D1 was detected in 72% (36) of OSCCs. Detection of positive amplification for cyclin D1 was observed in 88% (22) and 56% (14) of the tongue and cheek tumors, respectively, where the difference was statistically significant (P=0.012). Lymph node metastasis of cheek SCCs showed a trend towards a significant association (P= 0.098) with cyclin D1 amplification whereas the lymph node metastasis of tongue SCC was clearly not significant (P=0.593).There was a statistically significant correlation between cyclin D1 positivity and survival rate (P=0.009) for overall SCC cases and (P<0.001) for cheek SCC cases.

    CONCLUSION: The present study found that cyclin D1 amplification may differ in different subsites of OSCC (tongue vs cheek) and its positive amplification implies an overall poor survival in OSCCs, particularly those arising in cheeks.

    Matched MeSH terms: In Situ Hybridization, Fluorescence
  7. Expression and alteration of p16 in diffuse large B cell lymphoma
    Lee ES, Kim LH, Abdullah WA, Peh SC
    Pathobiology, 2010;77(2):96-105.
    PMID: 20332669 DOI: 10.1159/000278291
    This study aimed to examine (1) the expression of P16 protein relative to sites of presentation, immunophenotypic subgroups and proliferative indices of tumour cells, and (2) the relationship between p16 gene alterations and P16 protein overexpression in 70 cases of diffuse large B cell lymphoma (DLBCL).
    Matched MeSH terms: In Situ Hybridization, Fluorescence
  8. Reduction of DNA damage in older healthy adults by Tri E Tocotrienol supplementation
    Chin SF, Hamid NA, Latiff AA, Zakaria Z, Mazlan M, Yusof YA, et al.
    Nutrition, 2008 Jan;24(1):1-10.
    PMID: 17884341
    The free radical theory of aging (FRTA) suggests that free radicals are the leading cause of deteriorating physiologic function during senescence. Free radicals attack cellular structures or molecules such as DNA resulting in various modifications to the DNA structures. Accumulation of unrepaired DNA contributes to a variety of disorders associated with the aging process.
    Matched MeSH terms: In Situ Hybridization, Fluorescence
  9. Interaction of a tyrosine kinase inhibitor, vandetanib with human serum albumin as studied by fluorescence quenching and molecular docking
    Kabir MZ, Feroz SR, Mukarram AK, Alias Z, Mohamad SB, Tayyab S
    J Biomol Struct Dyn, 2016 Aug;34(8):1693-704.
    PMID: 26331959 DOI: 10.1080/07391102.2015.1089187
    Interaction of a tyrosine kinase inhibitor, vandetanib (VDB), with the major transport protein in the human blood circulation, human serum albumin (HSA), was investigated using fluorescence spectroscopy, circular dichroism (CD) spectroscopy, and molecular docking analysis. The binding constant of the VDB-HSA system, as determined by fluorescence quenching titration method was found in the range, 8.92-6.89 × 10(3 )M(-1) at three different temperatures, suggesting moderate binding affinity. Furthermore, decrease in the binding constant with increasing temperature revealed involvement of static quenching mechanism, thus affirming the formation of the VDB-HSA complex. Thermodynamic analysis of the binding reaction between VDB and HSA yielded positive ΔS (52.76 J mol(-1) K(-1)) and negative ΔH (-6.57 kJ mol(-1)) values, which suggested involvement of hydrophobic interactions and hydrogen bonding in stabilizing the VDB-HSA complex. Far-UV and near-UV CD spectral results suggested alterations in both secondary and tertiary structures of HSA upon VDB-binding. Three-dimensional fluorescence spectral results also showed significant microenvironmental changes around the Trp residue of HSA consequent to the complex formation. Use of site-specific marker ligands, such as phenylbutazone (site I marker) and diazepam (site II marker) in competitive ligand displacement experiments indicated location of the VDB binding site on HSA as Sudlow's site I (subdomain IIA), which was further established by molecular docking results. Presence of some common metal ions, such as Ca(2+), Zn(2+), Cu(2+), Ba(2+), Mg(2+), and Mn(2+) in the reaction mixture produced smaller but significant alterations in the binding affinity of VDB to HSA.
    Matched MeSH terms: Spectrometry, Fluorescence
  10. Increase number of mitochondrion-like organelle in symptomatic Blastocystis subtype 3 due to metronidazole treatment
    Raman K, Kumar S, Chye TT
    Parasitol Res, 2016 Jan;115(1):391-6.
    PMID: 26481491 DOI: 10.1007/s00436-015-4760-0
    Blastocystis sp., an intestinal organism is known to cause diarrhea with metronidazole regarded as the first line of treatment despite reports of its resistance. The conflicting reports of variation in drug treatment have been ascribed to subtype differences. The present study evaluated in vitro responses due to metronidazole on ST3 isolated from three symptomatic and asymptomatic patients, respectively. Symptomatic isolates were obtained from clinical patients who showed symptoms such as diarrhea and abdominal bloating. Asymptomatic isolates from a stool survey carried out in a rural area. These patients had no other pathogens other than Blastocystis. Ultrastructural studies using transmission electron microscopy (TEM) and scanning electron microscopy (SEM) revealed drug-treated ST3 from symptomatic patients were irregular and amoebic with surface showing high-convoluted folding when treated with metronidazole. These organisms had higher number of mitochondrion-like organelle (MLO) with prominent cristae. However, the drug-treated ST3 from asymptomatic persons remained spherical in shape. Asymptomatic ST3 showed increase in the size of its central body with the MLO located at the periphery.
    Matched MeSH terms: Microscopy, Fluorescence
  11. Fulltext The Curcumin Analogue 1,5-Bis(2-hydroxyphenyl)-1,4-pentadiene-3-one Induces Apoptosis and Downregulates E6 and E7 Oncogene Expression in HPV16 and HPV18-Infected Cervical Cancer Cells
    Paulraj F, Abas F, Lajis NH, Othman I, Hassan SS, Naidu R
    Molecules, 2015;20(7):11830-60.
    PMID: 26132907 DOI: 10.3390/molecules200711830
    In an effort to study curcumin analogues as an alternative to improve the therapeutic efficacy of curcumin, we screened the cytotoxic potential of four diarylpentanoids using the HeLa and CaSki cervical cancer cell lines. Determination of their EC50 values indicated relatively higher potency of 1,5-bis(2-hydroxyphenyl)-1,4-pentadiene-3-one (MS17, 1.03 ± 0.5 μM; 2.6 ± 0.9 μM) and 1,5-bis(4-hydroxy-3-methoxyphenyl)-1,4-pentadiene-3-one (MS13, 2.8 ± 0.4; 6.7 ± 2.4 μM) in CaSki and HeLa, respectively, with significantly greater growth inhibition at 48 and 72 h of treatment compared to the other analogues or curcumin. Based on cytotoxic and anti-proliferative activity, MS17 was selected for comprehensive apoptotic studies. At 24 h of treatment, fluorescence microscopy detected that MS17-exposed cells exhibited significant morphological changes consistent with apoptosis, corroborated by an increase in nucleosomal enrichment due to DNA fragmentation in HeLa and CaSki cells and activation of caspase-3 activity in CaSki cells. Quantitative real-time PCR also detected significant down-regulation of HPV18- and HPV16-associated E6 and E7 oncogene expression following treatment. The overall data suggests that MS17 treatment has cytotoxic, anti-proliferative and apoptosis-inducing potential in HPV-positive cervical cancer cells. Furthermore, its role in down-regulation of HPV-associated oncogenes responsible for cancer progression merits further investigation into its chemotherapeutic role for cervical cancer.
    Matched MeSH terms: Microscopy, Fluorescence
  12. Isolation, identification and characterization of chicken anaemia virus in Malaysia
    Chowdhury SM, Omar AR, Aini I, Hair-Bejo M, Jamaluddin AA, Kono Y, et al.
    J. Biochem. Mol. Biol. Biophys., 2002 Aug;6(4):249-55.
    PMID: 12186740
    A study was conducted to isolate and identify chicken anaemia virus (CAV) from field samples of clinically infected broiler chickens in Malaysia. A total of 125 samples were collected from chickens aged 2-6 weeks with clinically depressed and retarded growth, of which five samples were found positive to CAV directly by polymerase chain reaction (PCR). Later, five isolates of CAV from the respective five PCR positive samples were isolated in MDCC-MSB1 cells at passage 4 based on cytopathic effects, PCR and indirect immunofluorescent antibody test. The isolates were identified as BL-1, BL-2, BL-3, BL-4 and BL-5. These CAV isolates were found to resist treatment with chloroform and heat at 37 degrees C for 2 h, 56 degrees C for 30 min and 70 degrees C for 5 min. One of the isolates, BL-5 produced significant reduction (p < 0.001) of hematocrit values (9-19%), pale bone marrow, thymus atrophy and haemorrhages in skin/muscle when inoculated into 1-day old SPF chickens. Restriction enzyme digestion of 926 bp genomic fragments of all the isolates including Cux-1 isolate with HindIII exhibited a similar pattern of bands in 2% agarose gel. The present findings confirmed the presence of CAV in Malaysia.
    Matched MeSH terms: Microscopy, Fluorescence
  13. Fulltext Targeted PDT agent eradicates TrkC expressing tumors via photodynamic therapy (PDT)
    Kue CS, Kamkaew A, Lee HB, Chung LY, Kiew LV, Burgess K
    Mol Pharm, 2015 Jan 5;12(1):212-22.
    PMID: 25487316 DOI: 10.1021/mp5005564
    This contribution features a small molecule that binds TrkC (tropomyosin receptor kinase C) receptor that tends to be overexpressed in metastatic breast cancer cells but not in other breast cancer cells. A sensitizer for (1)O2 production conjugated to this structure gives 1-PDT for photodynamic therapy. Isomeric 2-PDT does not bind TrkC and was used as a control throughout; similarly, TrkC- cancer cells were used to calibrate enhanced killing of TrkC+ cells. Ex vivo, 1- and 2-PDT where only cytotoxic when illuminated, and 1-PDT, gave higher cell death for TrkC+ breast cancer cells. A 1 h administration-to-illumination delay gave optimal TrkC+/TrkC--photocytotoxicity, and distribution studies showed the same delay was appropriate in vivo. In Balb/c mice, a maximum tolerated dose of 20 mg/kg was determined for 1-PDT. 1- and 2-PDT (single, 2 or 10 mg/kg doses and one illumination, throughout) had similar effects on implanted TrkC- tumors, and like those of 2-PDT on TrkC+ tumors. In contrast, 1-PDT caused dramatic TrkC+ tumor volume reduction (96% from initial) relative to the TrkC- tumors or 2-PDT in TrkC+ models. Moreover, 71% of the mice treated with 10 mg/kg 1-PDT (n = 7) showed full tumor remission and survived until 90 days with no metastasis to key organs.
    Matched MeSH terms: Microscopy, Fluorescence
  14. The past, present, and prospective on UV-VIS-NIR skin photonics and spectroscopy-a wavelength guide
    Poh AH, Adikan FRM, Moghavvemi M
    Med Biol Eng Comput, 2020 Jun;58(6):1159-1175.
    PMID: 32319030 DOI: 10.1007/s11517-019-02077-9
    The study and applications of in vivo skin optics have been openly documented as early as the year 1954, or possibly earlier. To date, challenges in analyzing the complexities of this field remain, with wide scopes requiring more scrutiny. Recent advances in spectroscopic research and multivariate analytics allow a closer look into applications potentially for detecting or monitoring diseases. One of the challenges in this field is in establishing a reference for applications which correspond to certain bandwidths. This article reviews the scope on past research on skin spectroscopy, and the clinical aspects which have or may have applications on disease detection or enhancing diagnostics. A summary is supplied on the technicalities surrounding the measurements reported in literature, focused towards the wavelength-dependent applications in themes central to the respective research. Analytics on the topology of the papers' data cited in this work is also provided for a statistical perspective. In short, this paper strives to immediately inform the reader with possible applications via the spectroscopic devices at hand. Graphical Abstract .
    Matched MeSH terms: Spectrometry, Fluorescence
  15. Cytotoxicity Analysis of Morphologically Different Sol-Gel-Synthesized MgO Nanoparticles and Their In Vitro Insulin Resistance Reversal Ability in Adipose cells
    Jeevanandam J, Chan YS, Danquah MK, Law MC
    Appl Biochem Biotechnol, 2020 Apr;190(4):1385-1410.
    PMID: 31776944 DOI: 10.1007/s12010-019-03166-z
    Insulin resistance is one of the major factors that leads to type 2 diabetes. Although insulin therapies have been shown to overcome insulin resistance, overweight and hypoglycemia are still observed in most cases. The disadvantages of insulin therapies have driven the interest in developing novel curative agents with enhanced insulin resistance reversibility. Magnesium deficiency has also been recognized as a common problem which leads to insulin resistance in both type 1 and 2 diabetes. Oxide nanoparticles demonstrate highly tunable physicochemical properties that can be exploited by engineers to develop unique oxide nanoparticles for tailored applications. Magnesium supplements for diabetic cells have been reported to increase the insulin resistance reversibility. Hence, it is hypothesized that magnesium oxide (MgO) nanoparticles could be molecularly engineered to offer enhanced therapeutic efficacy in reversing insulin resistance. In the present work, morphologically different MgO nanoparticles were synthesized and evaluated for biophysical characteristics, biocompatibility, cytotoxicity, and insulin resistance reversibility. MTT assay revealed that hexagonally shaped MgO nanoparticles are less toxic to 3T3-L1 adipose cells (diabetic) compared with spherically and rod-shaped MgO nanoparticles. MTT assays using VERO cells (normal, non-diabetic) showed that 400 μg/ml of hexagonal MgO nanoparticles were less toxic to both diabetic and non-diabetic cells. DNS glucose assay and western blot showed that hexagonally shaped MgO nanoparticles had reversed 29.5% of insulin resistance whilst fluorescence microscopy studies indicated that the insulin resistance reversal is due to the activation of intracellular enzymes. The probable mechanism for MgO nanoparticles to induce cytotoxic effect and insulin resistance reversal is discussed.
    Matched MeSH terms: Microscopy, Fluorescence
  16. Activation of phosphatidylinositol 3-kinase/Akt signaling by EGF downregulates membranous E-cadherin and β-catenin and enhances invasion in nasopharyngeal carcinoma cells
    Yip WK, Seow HF
    Cancer Lett, 2012 May 28;318(2):162-72.
    PMID: 22182447 DOI: 10.1016/j.canlet.2011.12.018
    Dysregulation of E-cadherin and β-catenin function in cell-cell adhesion is common in nasopharyngeal carcinoma (NPC) and correlates with metastatic disease. In this study, we examined the role of EGF-activated phosphatidylinositol 3-kinase (PI3K)-Akt signaling in E-cadherin and β-catenin regulation. We found that reduced membranous E-cadherin and β-catenin expression was positively correlated with Akt phosphorylation in NPC tissues. EGF treatment disrupted cell-cell adhesion and resulted in mesenchymal morphological features in NPC cell lines (TW01, TW04, and TW06). Western blot analysis showed that the E-cadherin protein level was partially reduced in TW04 cells only and the β-catenin levels were not considerably affected upon EGF treatment. In contrast, quantitative real-time RT-PCR showed that the E-cadherin, but not β-catenin, mRNA levels were markedly reduced by EGF in all cell lines. Immunofluorescent staining revealed that E-cadherin and β-catenin appeared to be markedly reduced on the cell surface and more localized in the cytoplasm. Inhibition of PI3K by LY294002 did not abolish the EGF-induced downregulation of E-cadherin protein or mRNA in TW04 cells but moderately increased the β-catenin protein level in TW01 cells and mRNA level in TW06 cells. However, LY294002 substantially restored or increased cell surface E-cadherin and β-catenin in all EGF-treated cell lines, in concordance with the inhibition of cell morphological changes. Moreover, LY294002 significantly blocked EGF-driven cell invasion, correlating with the elevation of membranous E-cadherin and β-catenin levels. In conclusion, EGF-induced epithelial-to-mesenchymal transition may not be only dependent on downregulation of E-cadherin protein/mRNA but also on mislocalization of E-cadherin and β-catenin. The mechanisms involved may be related, at least in part, to the PI3K-Akt pathway.
    Matched MeSH terms: Microscopy, Fluorescence
  17. Evidence for Delivery of Abraxane via a Denatured-Albumin Transport System
    Hama M, Ishima Y, Chuang VTG, Ando H, Shimizu T, Ishida T
    ACS Appl Mater Interfaces, 2021 May 05;13(17):19736-19744.
    PMID: 33881292 DOI: 10.1021/acsami.1c03065
    Abraxane, an albumin-bound paclitaxel nanoparticle formulation, is superior to conventional paclitaxel preparations because it has better efficacy against unresectable pancreatic cancer. Previous reports suggest that this better efficacy of Abraxane than conventional paclitaxel preparation is probably due to its transport through Gp60, an albumin receptor on the surface of vascular endothelial cells. The increased tumor accumulation of Abraxane is also caused by the secreted protein acid and rich in cysteine in the tumor stroma. However, the uptake mechanism of Abraxane remains poorly understood. In this study, we demonstrated that the delivery of Abraxane occurred via different receptor pathways from that of endogenous albumin. Our results showed that the uptake of endogenous albumin was inhibited by a Gp60 pathway inhibitor in the process of endocytosis through endothelial cells or tumor cells. In contrast, the uptake of Abraxane-derived HSA was less affected by the Gp60 pathway inhibitor but significantly reduced by denatured albumin receptor inhibitors. In conclusion, these data indicate that Abraxane-derived HSA was taken up into endothelial cells or tumor cells by a mechanism different from normal endogenous albumin. These new data on distinct cellular transport pathways of denatured albumin via gp family proteins different from those of innate albumin shed light on the mechanisms of tumor delivery and antitumor activity of Abraxane and provide new scientific rationale for the development of a novel albumin drug delivery strategy via a denatured albumin receptor.
    Matched MeSH terms: Spectrometry, Fluorescence
  18. Combinatorial effect of genistein and female sex-steroids on uterine fluid volume and secretion rate and aquaporin (AQP)-1, 2, 5, and 7 expression in the uterus in rats
    Chinigarzadeh A, Muniandy S, Salleh N
    Environ Toxicol, 2017 Mar;32(3):832-844.
    PMID: 27235753 DOI: 10.1002/tox.22283
    We hypothesized that genistein can interfere with the regulation of uterine fluid volume, secretion rate and expression of aquaporin in the uterus by female sex-steroids, i.e., estrogen and progesterone. Therefore, the aims of this study were to investigate changes in these parameters in the presence of genistein and female sex-steroids.

    METHODS: Female Sprague-Dawley rats were ovariectomized and received 3-days estradiol-17β benzoate (E2) plus genistein (25, 50, or 100 mg kg(-1)  day(-1) ) or 3-days E2 followed by 3-days E2 plus progesterone with genistein (25, 50, or 100 mg kg(-1)  day(-1) ). A day after last treatment, uterine fluid secretion rate was determined by in vivo uterine perfusion with rats under anesthesia. Animals were sacrificed and uteri were harvested and subjected for histological analyses. Luminal/outer uterine circumference was determined and distribution of AQP-1, 2, 5, and 7 in endometrium was visualized by immunofluorescence. Expression of AQP-1, 2, 5, and 7 proteins and mRNAs were determined by Western blotting and Real-time PCR respectively.

    RESULTS: Combined treatment of E2 with high dose genistein (50 and 100 mg kg(-1)  day(-1) ) resulted in significant decrease in uterine fluid volume, secretion rate and expression of AQP-1, 2, 5, and 7 proteins and mRNAs in uterus (p 

    Matched MeSH terms: Microscopy, Fluorescence
  19. Fulltext Quantitative analysis of ERG expression and its splice isoforms in formalin-fixed, paraffin-embedded prostate cancer samples: association with seminal vesicle invasion and biochemical recurrence
    Hagen RM, Adamo P, Karamat S, Oxley J, Aning JJ, Gillatt D, et al.
    Am J Clin Pathol, 2014 Oct;142(4):533-40.
    PMID: 25239421 DOI: 10.1309/AJCPH88QHXARISUP
    The proto-oncogene ETS-related gene (ERG) is consistently overexpressed in prostate cancer. Alternatively spliced isoforms of ERG have variable biological activities; inclusion of exon 11 (72 base pairs [bp]) is associated with aggressiveness and progression of disease. Exon 10 (81 bp) has also been shown to be alternatively spliced. Within this study, we assess whether ERG protein, messenger RNA (mRNA), and ERG splice isoform mRNA expression is altered as prostate cancer progresses.
    Matched MeSH terms: In Situ Hybridization, Fluorescence
  20. Fulltext Phosphorylated and Nonphosphorylated PfMAP2 Are Localized in the Nucleus, Dependent on the Stage of Plasmodium falciparum Asexual Maturation
    Dahalan FA, Sidek HM, Murtey MD, Embi MN, Ibrahim J, Fei Tieng L, et al.
    Biomed Res Int, 2016;2016:1645097.
    PMID: 27525262 DOI: 10.1155/2016/1645097
    Plasmodium falciparum mitogen-activated protein (MAP) kinases, a family of enzymes central to signal transduction processes including inflammatory responses, are a promising target for antimalarial drug development. Our study shows for the first time that the P. falciparum specific MAP kinase 2 (PfMAP2) is colocalized in the nucleus of all of the asexual erythrocytic stages of P. falciparum and is particularly elevated in its phosphorylated form. It was also discovered that PfMAP2 is expressed in its highest quantity during the early trophozoite (ring form) stage and significantly reduced in the mature trophozoite and schizont stages. Although the phosphorylated form of the kinase is always more prevalent, its ratio relative to the nonphosphorylated form remained constant irrespective of the parasites' developmental stage. We have also shown that the TSH motif specifically renders PfMAP2 genetically divergent from the other plasmodial MAP kinase activation sites using Neighbour Joining analysis. Furthermore, TSH motif-specific designed antibody is crucial in determining the location of the expression of the PfMAP2 protein. However, by using immunoelectron microscopy, PPfMAP2 were detected ubiquitously in the parasitized erythrocytes. In summary, PfMAP2 may play a far more important role than previously thought and is a worthy candidate for research as an antimalarial.
    Matched MeSH terms: Microscopy, Fluorescence
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