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Beta-Lapachone a novel topoisomerase inhibitor, has been found to induce apoptosis in various human cancer cells. In this study we report that a dramatic elevation of hydrogen peroxide (H2O2) in human leukemia HL-60 cells following 1 microM beta-lapachone treatment and that this increase was
Up-regulation of telomerase activity is associated with immortalization and unlimited cell division in most cancer cells. Therefore, telomerase represents a particularly attractive target for anticancer therapy. Recent reports have suggested that beta-lapachone (LAPA), the product of the South
beta-Lapachone and certain of its derivatives directly bind and inhibit topoisomerase I (Topo I) DNA unwinding activity and form DNA-Topo I complexes, which are not resolvable by SDS-K+ assays. We show that beta-lapachone can induce apoptosis in certain cells, such as in human promyelocytic leukemia
We previously demonstrated that beta-lapachone (beta-lap) killed cancer cells solely by apoptosis. Beta-Lap induced apoptosis in HL-60 cells in a dose-dependent manner as measured by flow cytometry and DNA ladder formation. Cell cycle changes, such as accumulations in S and G2-phases, were not
Beta-lapachone (beta-Lap) has been found to inhibit DNA topoisomerases (Topos) by a mechanism distinct from that of other commonly known Topo inhibitors. Here, we demonstrated a pronounced elevation of H2O2 and O2- in human leukemia HL-60 cells treated with beta-Lap. Treatment with other Topo
Nor-β-lapachone has shown several biological properties. Regarding cytotoxic activity against cancer cell lines, it has been recognized as an important prototype. However, quinonoid drugs present a major challenge because of their toxicity. In this study, we evaluated the cytotoxicity and genetic
In order to find a 3,4-dihydro-2H-naphtho[1,2-b]pyran-5,6-dione more potent than the naturally occurring 2,2-dimethyl derivative [beta-lapachone (10a)], we synthesized a series of analogous compounds with modifications at position 2 of the pyran ring or at positions 8 and 9 of the benzene ring. Of
beta-Lapachone is a naturally occuring compound that can be isolated from a number of tropical trees. It is shown to be a potent inhibitor of reverse transcriptase activity from both avian myeloblastosis virus and Rauscher murine leukaemia virus. In addition, it affects eukaryotic DNA-dependent DNA
beta-lapachone (beta-lap) is a lipophilic o-naphthoquinone isolated from the bark of the lapacho tree. Initial observations proved its capability for inhibiting growth of Yoshida tumor and Walker 256 carcinosarcoma. beta-Lap redox-cycling in the presence of reductants and oxygen yields "reactive
BACKGROUND
Human colon cancers have a high frequency of p53 mutations, and cancer cells expressing mutant p53 tend to be resistant to current chemo- and radiation therapy. It is thus important to find therapeutic agents that can inhibit colon cancer cells with altered p53 status. beta-Lapachone, a
Several 3-arylamino and 3-alkoxy-nor-beta-lapachone derivatives were synthesized in moderate to high yields and found to be highly potent against cancer cells SF295 (central nervous system), HCT8 (colon), MDA-MB435 (melanoma), and HL60 (leukemia), with IC(50) below 2 microM. The arylamino para-nitro
Several arylamino derivatives of nor-beta-lapachone were synthesized in moderate to high yields and found to show very potent cytotoxicity against six neoplastic cancer cells: SF-295 (central nervous system), HCT-8 (colon), MDAMB-435 (breast), HL-60 (leukaemia), PC-3 (prostate), and B-16 (murine
beta-Lapachone, a plant product, has been shown to be a novel inhibitor of DNA topoisomerase I, with a mode of action different from camptothecin and a chemical structure distinct from those of current anti-cancer drugs. We observed that beta-lapachone, at concentrations of less than 8 microM,
Naphthoquinones are considered privileged structures for anticancer drug molecules. The Heck reaction of 2-hydroxy-1,4-naphthoquinone (lawsone) with 1-bromo-3-methyl-2-butene offered easy access to lapachol. Several naturally occurring linear and angular heterocyclic quinoids (α-lapachone,
Chalcogen-containing β-lapachone derivatives were synthesized using a straightforward methodology and evaluated against several cancer cell lines (leukaemia, human colon carcinoma, prostate, human metastatic prostate, ovarian, central nervous system and breast), showing, in some cases, IC50 values