Publications (4)13.32 Total impact
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Article: Trans-resveratrol boronic acid exhibits enhanced anti-proliferative activity on estrogen-dependent MCF-7 breast cancer cells.
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ABSTRACT: Resveratrol (RSV), a natural compound present in the skin and seeds of red grapes, is considered a phytoestrogen and has structural similarity to the synthetic estrogen diethylstilbestrol. RSV inhibits tumor cell growth in estrogen receptor-positive (ER+) and negative (ER-) breast cancer cell lines resulting in cell specific regulation of the G1/S and G2/M stages of the cell cycle. However apoptotic cell death was only observed in ER+ MCF-7 cells. In this study, we designed and synthesized boronic acid derivative of RSV and evaluated their biological effects on ER+ MCF-7 breast cancer cells. The trans-4 analog inhibited the growth of MCF-7 cells and is not a substrate for p-glycoprotein. The trans-4 analog induces G1 cell cycle arrest, which coincides with marked inhibition of G1 cell cycle proteins and a greater pro-apoptotic effect. Finally, the trans-4 analog had no effect on the estrogen-stimulated growth of MCF-7 cells. Our results demonstrate that the trans-4 analog inhibits MCF-7 breast cancer cells by a different mechanism of action than that of RSV (S-phase arrest), and provides a new class of novel boronic acids of RSV that inhibit breast cancer cell growth.Cancer biology & therapy 08/2012; 13(10):925-34. · 2.64 Impact Factor -
Article: Fluorescent cyclin-dependent kinase inhibitors block the proliferation of human breast cancer cells.
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ABSTRACT: Inhibitors of cyclin-dependent kinases (CDKs) are an emerging class of drugs for the treatment of cancers. CDK inhibitors are currently under evaluation in clinical trials as single agents and as sensitizers in combination with radiation therapy and chemotherapies. Drugs that target CDKs could have important inhibitory effects on cancer cell cycle progression, an extremely important mechanism in the control of cancer cell growth. Using rational drug design, we designed and synthesized fluorescent CDK inhibitors (VMY-1-101 and VMY-1-103) based on a purvalanol B scaffold. The new agents demonstrated more potent CDK inhibitory activity, enhanced induction of G2/M arrest and modest apoptosis as compared to purvalanol B. Intracellular imaging of the CDK inhibitor distribution was performed to reveal drug retention in the cytoplasm of treated breast cancer cells. In human breast cancer tissue, the compounds demonstrated increased binding as compared to the fluorophore. The new fluorescent CDK inhibitors showed undiminished activity in multidrug resistance (MDR) positive breast cancer cells, indicating that they are not a substrate for p-glycoprotein. Fluorescent CDK inhibitors offer potential as novel theranostic agents, combining therapeutic and diagnostic properties in the same molecule.Bioorganic & medicinal chemistry 03/2011; 19(8):2714-25. · 2.82 Impact Factor -
Article: VMY-1-103, a dansylated analog of purvalanol B, induces caspase-3-dependent apoptosis in LNCaP prostate cancer cells.
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ABSTRACT: The 2,6,9-trisubstituted purine group of cyclin dependent kinase inhibitors have the potential to be clinically relevant inhibitors of cancer cell proliferation. We have recently designed and synthesized a novel dansylated analog of purvalanol B, termed VMY-1-103, that inhibited cell cycle progression in breast cancer cell lines more effectively than did purvalanol B and allowed for uptake analyses by fluorescence microscopy. ErbB-2 plays an important role in the regulation of signal transduction cascades in a number of epithelial tumors, including prostate cancer (PCa). Our previous studies demonstrated that transgenic expression of activated ErbB-2 in the mouse prostate initiated PCa and either the overexpression of ErbB-2 or the addition of the ErbB-2/ErbB-3 ligand, heregulin (HRG), induced cell cycle progression in the androgen-responsive prostate cancer cell line, LNCaP. In the present study, we tested the efficacy of VMY-1-103 in inhibiting HRG-induced cell proliferation in LNCaP prostate cancer cells. At concentrations as low as 1 μM, VMY-1-103 increased both the proportion of cells in G(1) and p21(CIP1) protein levels. At higher concentrations (5 μM or 10 μM), VMY-1-103 induced apoptosis via decreased mitochondrial membrane polarity and induction of p53 phosphorylation, caspase-3 activity and PARP cleavage. Treatment with 10 μM Purvalanol B failed to either influence proliferation or induce apoptosis. Our results demonstrate that VMY-1-103 was more effective in inducing apoptosis in PCa cells than its parent compound, purvalanol B, and support the testing of VMY-1-103 as a potential small molecule inhibitor of prostate cancer in vivo.Cancer biology & therapy 08/2010; 10(4):320-5. · 2.64 Impact Factor -
Article: Tumor-targeting nanodelivery enhances the anticancer activity of a novel quinazolinone analogue.
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ABSTRACT: GMC-5-193 (GMC) is a novel anticancer small-molecule quinazolinone analogue with properties that include antimicrotubule activity and inherent fluorescence. The aim of this study was to produce and optimize a systemically administered liposomal formulation for tumor-targeting delivery of GMC to enhance the anticancer effect of this compound and evaluate its bioefficacy. GMC was encapsulated within a cationic liposome, which was decorated on the surface with an anti-transferrin receptor single-chain antibody fragment (TfRscFv) as the tumor-targeting moiety to form a nanoscale complex (scL/GMC). Confocal imaging of fluorescent GMC uptake in a human melanoma cell line, MDA-MB-435, showed higher cellular uptake of GMC when delivered via the liposome complex compared with free GMC. Delivery of GMC by the tumor-targeting liposome nanoimmunocomplex also resulted in a 3- to 4-fold decrease in IC(50) values in human cancer cells [DU145 (prostate) and MDA-MB-435] compared with the effects of GMC administered as free GMC. In addition, the GMC nanoimmunocomplex increased the sensitivity of cancer cells to doxorubicin, docetaxel, or mitoxantrone by approximately 3- to 30-fold. In the MDA435/LCC6 athymic nude mice xenograft lung metastases model, GMC was specifically delivered to tumors by the nanoimmunocomplex. These data show that incorporation of small-molecule therapeutic GMC within the tumor-targeting liposome nanocomplex enhances its anticancer effect.Molecular Cancer Therapeutics 04/2008; 7(3):559-68. · 5.23 Impact Factor
Top Journals
Institutions
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2011–2012
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Georgetown University
- Department of Oncology
Washington, D. C., DC, USA
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