At elevated levels, homocysteine (Hcy, 1) is a risk factor for cardiovascular diseases, Alzheimer's disease, neural tube defects, and osteoporosis. Both 1 and cysteine (Cys, 3) are linked to neurotoxicity. The biochemical mechanisms by which 1 and 3 are involved in disease states are relatively unclear. Herein, we describe simple methods for detecting either Hcy or Cys in the visible spectral region with the highest selectivity reported to date without using biochemical techniques or preparative separations. Simple methods and readily available reagents allow for the detection of Cys and Hcy in the range of their physiologically relevant levels. New HPLC postcolumn detection methods for biological thiols are reported. The potential biomedical relevance of the chemical mechanisms involved in the detection of 1 is described.
Abstract. Cranberry extracts may provide beneficial health effects in the treatment of various diseases, including cancer. However, the underlying molecular mechanisms of antineoplastic properties are not understood. We report the effect of a proanthocyanidin (PAC)-rich isolate from cranberry (PAC-1) as a therapeutic agent with dual activity to target both ovarian cancer viability and angiogenesis in vitro. PAC-1 treatment of chemotherapy-resistant SKOV-3 cells blocked cell cycle progression through the G 2 /M phase, increased the generation of reactive oxygen species (ROS), and induced apoptosis through activation of intrinsic and extrinsic pathway components. Cytotoxicity of PAC-1 was partially based on ROS generation and could be blocked by co-treatment with antioxidant glutathione. PAC-1 reduced the cell viability of both SKOV-3 ovarian cancer cells and HUVEC endothelial cells in a dose-dependent manner and blocked the activation of the pro-survival factor AKT. Furthermore, PAC-1 blocked vascular endothelial growth factor (VEGF)-stimulated receptor phosphorylation in endothelial cells, which correlated with the inhibition of endothelial tube formation in vitro. Our findings suggest that PAC-1 exerts potent anticancer and anti-angiogenic properties and that highly purified PAC from cranberry can be further developed to treat ovarian cancer in combinational or single-agent therapy.
Polyphenolic extracts of the principal flavonoid classes present in cranberry were screened in vitro for cytotoxicity against solid tumor cells lines, identifying two fractions composed principally of proanthocyanidins (PACs) with potential anticancer activity. Matrix-Assisted Laser Desorption/ Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF-MS) analysis of the proanthocyanidins (PACs) fractions indicated the presence of A-type PACs with 1-4 linkages containing between 2-8 epicatechin units with a maximum of 1 epigallocatechin unit. PACs exhibited in vitro cytotoxicity against platinum-resistant human ovarian, neuroblastoma and prostate cancer cell lines (IC 50 = 79-479 μg/mL) but were non-cytotoxic to lung fibroblast cells (IC 50 > 1000 μg/ml). SKOV-3 ovarian cancer cells treated with PACs exhibited classic apoptotic changes. PACs acted synergistically with paraplatin in SKOV-3 cells. Pretreatment of SKOV-3 cells with PACs (106 μg/ ml) resulted in a significant reduction of the paraplatin IC 50 value. Similarly, in a BrdU incorporation assay, cotreatment of SKOV-3 cells with PACs and paraplatin revealed reduced cell proliferation at lower concentrations than with either individually. In SKOV-3 cell cultures co-treated with PAC-1 and paraplatin, an HPLC analysis indicated differential quantitative presence of various PAC oligomers such as DP-8, -9, -11 and -14 indicating either selective binding or uptake. Cranberry proanthocyanidins exhibit cell-line specific cytotoxicity, induce apoptotic markers and augment cytotoxicity of paraplatin in platinum-resistant SKOV-3 ovarian cancer cells.
BackgroundIn this pioneer study to the biological activity of organometallic compound Iron(III)-salophene (Fe-SP) the specific effects of Fe-SP on viability, morphology, proliferation, and cell-cycle progression on platinum-resistant ovarian cancer cell lines were investigated.Methodology/Principal FindingsFe-SP displayed selective cytotoxicity against SKOV-3 and OVCAR-3 (ovarian epithelial adenocarcinoma) cell lines at concentrations between 100 nM and 1 µM, while the viability of HeLa cells (epithelial cervix adenocarcinoma) or primary lung or skin fibroblasts was not affected. SKOV-3 cells in contrast to fibroblasts after treatment with Fe-SP revealed apparent hallmarks of apoptosis including densely stained nuclear granular bodies within fragmented nuclei, highly condensed chromatin and chromatin fragmentation. Fe-SP treatment led to the activation of markers of the extrinsic (Caspase-8) and intrinsic (Caspase-9) pathway of apoptosis as well as of executioner Caspase-3 while PARP-1 was deactivated. Fe-SP exerted effects as an anti-proliferative agent with an IC50 value of 300 nM and caused delayed progression of cells through S-phase phase of the cell cycle resulting in a complete S-phase arrest. When intra-peritoneally applied to rats Fe-SP did not show any systemic toxicity at concentrations that in preliminary trials were determined to be chemotherapeutic relevant doses in a rat ovarian cancer cell model.Conclusion/SignificanceThe present report suggests that Fe-SP is a potent growth-suppressing agent in vitro for cell lines derived from ovarian cancer and a potential therapeutic drug to treat such tumors in vivo.
Several discreet sugar-boronate complexes exist in solution. This is due to the complex equilibria between isomeric species of even the simplest monosaccharides. In the current investigation, we determine the regio- and stereochemical features of the various equilibrating sugar isomers that induce signal transduction in boronic acid chemosensors such as 1 as well as 2 and 3. We present a unique example of a chemosensor (1) that is selective for ribose, adenosine, nucleotides, nucleosides, and congeners. As a result of this study, we are able to predict and achieve selective fluorescence and colorimetric responses to specific disaccharides as a consequence of their terminal sugar residue linkage patterns and configurations. We also find that the combined use of chemosensors exhibiting complementary reactivities may be used cooperatively to obtain enhanced selectivity for ribose and rare saccharides.
The colorimetric properties of resorcinarene solutions had not been investigated since Baeyer's initial synthesis. We recently reported that solutions containing resorcinarene macrocycles develop color upon heating or standing. In the presence of saccharides, these solutions exhibit significant color changes which are easily seen. We herein present strong evidence that the solution color is due to macrocycle ring opening and oxidation. The optical responses to saccharides are due to complexation of the sugar with the acyclic chromophores. We apply these mechanistic insights toward the challenging problem of the visual detection of neutral oligosaccharides by simple chromogens. In addition, we also report the first single-crystal X-ray crystal structure determination of a rarely observed "diamond" resorcinarene stereoisomer.
The cytotoxic, anti-proliferative and apoptotic effects of 3-Bromoacetoxy Calcidiol (B3CD), a derivative of vitamin D 3 precursor calcidiol, on human neuroblastoma (NB) cells were examined. NB, predominantly a tumor of early childhood, is the most common extracranial solid tumor. Despite aggressive treatments, survival for advanced stages remains low and novel treatment strategies are needed. B3CD-induced apoptosis in various neuroblastic cells via caspases-3 and -9 activation. B3CD upregulated mitochondrial pro-apoptotic Bax and anti-apoptotic Bcl-2 expression, caused cytochrome c release, downregulated N-Myc expression and activated pro-survival marker Akt. Accordingly, B3CD treatment dose dependently reduced the viability of NB cells with IC 50 values between 1 and 3 μM. The cytotoxicity of B3CD was significantly higher than for the calcemic parentcompound vitamin D 3 (IC 50 between 10 and 30 μM). Further studies revealed that B3CD treatment inhibits the proliferation of NB cells at low concentrations (IC 50 between 30 and 100 nM). Cell cycle analysis showed a dramatic increase in the apoptotic sub-diploidal population along with a cell cycle block. In summary, the present study shows that B3CD is toxic to NB cells via suppression of cell proliferation and cell viability by caspase activation and regulation of survival signals. These results suggest that B3CD could be developed as a treatment for NB. Keywords chemical biology; drug design; kinases; signal transductionNeuroblastoma (NB), predominantly a tumor of early childhood, is the most common extracranial solid tumor. Two-thirds of the cases occur in children below the age of five. NB account for 7-10% of all childhood cancers; in the majority of patients older than 1 year of age, the disease is fatal (1). There are approximately 500-1000 new cases of NB in the USA each year (2). Treatment methods currently available include surgery, radiation therapy, chemotherapy, and autologous stem cell transplantation (3-5) either alone or in combination, depending on the location and biological characteristics of the cancer cells, stage and the risk group to which the patient belongs. However, despite intensive multimodality treatment, more than 50% of children with high-risk disease relapse, because of drug-resistant residual disease *Corresponding author: Laurent Brard, lbrard@wihri.org; Laurent_Brard_MD@Brown.edu Thilo S. Lange and Rakesh K. Singh contributed equally to the manuscript. [6][7][8]. Eradication of refractory microscopic disease remains one of the most significant challenges in the treatment of the high-risk NB and innovative treatments need to be designed. NIH Public AccessCalcitriol/vitamin D 3 (1,25-dihydroxy-vitamin D 3 ) (Figure 1), an endocrine hormone responsible for calcium and mineral homeostasis, inhibits cell proliferation and induces differentiation, via binding to the vitamin D receptor (VDR) (9). Its clinical use in cancer therapy is limited by its hypercalcemic side-effects (10-12). Synthetic analogs of calcitriol/ vitamin D ...
Summary The objective of the present study was to test the hypothesis that Calcidiol derivative B3CD qualifies as a potential anti-cancer drug in vivo employing an ovarian cancer xenograft model in mice. In addition, the selectivity of B3CD on viability and proliferation of platinum-resistant human ovarian cancer cell lines in comparison to control cell lines was analyzed in vitro. B3CD displayed cell line-specific cytotoxicity screened against a panel of ovarian and other carcinoma cell lines, endothelial and control cells. B3CD, at sub-cytotoxic concentrations, revealed stronger effects on the proliferation of SKOV-3 ovarian cancer cells vs. primary fibroblasts as determined by BrdU incorporation analysis. Treatment with B3CD at 0.5 μM resulted in highly condensed chromatin and fragmented nuclei in SKOV-3 cells but not in primary fibroblasts. B3CD induced cell death at low drug concentrations (≤0.5 μM) in SKOV-3 ovarian cancer cells is mediated by the p38 MAPK signaling pathway: B3CD induced p38 MAPK expression and activation in SKOV-3 cells and inhibition of p38 signaling counteracted B3CD induced cell death in vitro. An ovarian cancer cell animal model (human SKOV-3 cell derived xenografts in nude mice) revealed that tumor growth in few B3CD treated mice accelerated while the majority of B3CD treated mice displayed delayed tumor growth or full tumor regression. B3CD possesses anti-ovarian cancer properties in vitro and in vivo. We propose the further development of non-calcemic bromoacetoxy derivatives of vitamin D3 as potential anti-cancer therapeutics.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.