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ABSTRACT: A series of twenty-one 7-chloro-4-quinolinylhydrazones derivatives (3a-u) have been synthesized and evaluated for their cytotoxic potential against three cancer cell lines using MTT assay. The compounds 3b, 3e, 3f, 3h, 3j, 3n, 3r and 3u displayed more than 90% of growth inhibition (GI) and they were selected for in vitro anticancer activities evaluation against four human cancer cell lines. These results were expressed as the concentrations that induce 50% inhibition of cell growth (IC50) in μg/mL. Considering that, compounds 3b, 3e, 3h, 3n, 3r and 3u exhibited good cytotoxic activity against at least three cancer cell lines (0.7967-4.200 μg/mL). In general, we observed that the presence of electron-withdrawing groups in the benzene ring is important for the anticancer activity in this series, such as fluorine (3h), chlorine (3b) amd bromine (3e) groups in meta position and nitro group (3r) in para position. These derivatives could be considered interesting start points to develop a new anticancer drug and confirm the potential of chloroquine derivatives as lead compounds in anticancer drug discovery.
Medicinal chemistry (Shāriqah (United Arab Emirates)) 11/2011; 7(6):599-604. · 1.64 Impact Factor
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ABSTRACT: A series of eleven (E)-2-benzothiazole hydrazones were synthesized and evaluated for their in vitro anticancer activities against three neoplastic cancer cells: HL-60 (leukemia), MDAMB-435 (breast) and HCT-8 (colon). Two of them, 3e and 3f, showed good cytotoxicity activity for HL-60. The results also demonstrated that compound 3f seems to be selective to HL-60 cell line, appearing as a good prototype for an antileukemia lead molecule.
Letters in Drug Design & Discovery 09/2010; 7(8):551-555. · 0.87 Impact Factor
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Raquel Carvalho Montenegro,
Ana Jérsia Araújo,
María Teresa Molina,
José Delano Barreto Marinho Filho,
Danilo Damasceno Rocha,
Eulogio Lopéz-Montero,
Marília O F Goulart,
E S Bento,
Ana Paula Nunes Negreiros Alves,
Cláudia Pessoa,
Manoel Odorico de Moraes,
Letícia Veras Costa-Lotufo
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ABSTRACT: The cytotoxicity of nine naphthoquinones (NQ) was assayed against HL-60 (leukaemia), MDA-MB-435 (melanoma), SF-295 (brain) and HCT-8 (colon), all human cancer cell lines, and peripheral blood mononuclear cells (PBMC), as representatives of normal cells, after 72h of incubation. 5-Methoxy-1,4-naphthoquinone was the most active compound, showing IC(50) values in the range of 0.31 (1.7microM) in HL-60 to 0.88microg/mL (4.7microM) in SF-295 and IC(50) of 0.69microg/mL (3.7microM) against PBMC. With the introduction of a bromo-substituent in position 2 or 3 of juglone, the IC(50) significantly decreased, regardless of the position on the NQ moiety. However, compared with juglone methyl ether, the halogen substitution decreased the activity. To further understand the mechanism underlying the cytotoxicity of 5-methoxy-1,4-naphthoquinone, studies involving DNA fragmentation, cell cycle analysis, phosphatidyl serine externalization, mitochondrial depolarization and activation of caspases 8 and 3/7 were performed in HL-60 cell line, using doxorubicin as a positive control. The results indicate that the cytotoxic 5-methoxy-1,4-naphthoquinone activates caspases 8 and 3/7 and thus induces apoptosis independent of mitochondria.
Chemico-biological interactions 02/2010; 184(3):439-48. · 2.46 Impact Factor
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ABSTRACT: Pristimerin has been shown to be cytotoxic to several cancer cell lines. In the present work, the cytotoxicity of pristimerin was evaluated in human tumor cell lines and in human peripheral blood mononuclear cells (PBMC). This work also examined the effects of pristimerin (0.4; 0.8 and 1.7 microM) in HL-60 cells, after 6, 12 and 24h of exposure. Pristimerin reduced the number of viable cells and increased number of non-viable cells in a concentration-dependent manner by tripan blue test showing morphological changes consistent with apoptosis. Nevertheless, pristimerin was not selective to cancer cells, since it inhibited PBMC proliferation with an IC50 of 0.88 microM. DNA synthesis inhibition assessed by 5-bromo-2'-deoxyuridine (BrdU) incorporation in HL-60 cells was 70% and 83% for the concentrations of 0.4 and 0.8 microM, respectively. Pristimerin (10 and 20 microM) was not able to inhibit topoisomerase I. In AO/EB (acridine orange/ethidium bromide) staining, all tested concentrations reduced the number of HL-60 viable cells, with the occurrence of necrosis and apoptosis in a concentration-dependent manner, results in agreement with trypan blue exclusion findings. The analysis of membrane integrity and internucleosomal DNA fragmentation by flow cytometry in the presence of pristimerin indicated that treated cells underwent apoptosis. The present data point to the importance of pristimerin as representative of an emerging class of potential anticancer chemicals, exhibiting an antiproliferative effect by inhibiting DNA synthesis and triggering apoptosis.
Toxicology in Vitro 07/2008; 22(4):854-63. · 2.78 Impact Factor
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ABSTRACT: It has been reported that pisosterol was active against cancer cells but lacked activity on the development of sea urchin eggs. Recently, it was reported that pisosterol induces differentiation in leukemia cell line. The present study evaluated the in vivo antitumor activity of pisosterol a triterpene isolated from Pisolithus tinctorius. Histopathological and morphological analyses of the tumor and the organs, including liver, spleen and kidney, were performed in order to evaluate toxicological aspects associated with pisosterol treatments. Antitumor activity of pisosterol (50 or 100 mg/m2) was confirmed in mice bearing Sarcoma 180 tumor cells. The tumor growth inhibition ratios were 43.0% and 38.7% for mice treated with pisosterol at 50 and 100 mg/m2, respectively. Histopathological analysis of liver, kidney and spleen was also evaluated. Liver and kidney were the major affected organs by pisosterol, although the observed alterations can be considered reversible.
Biological & Pharmaceutical Bulletin 04/2008; 31(3):454-7. · 1.66 Impact Factor
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ABSTRACT: The aim of this study was to determine whether the antiproliferative effects observed for pisosterol, a cytotoxic triterpene isolated from Pisolithus tinctorius, are related to cell differentiation induction using HL-60 cell line as a model. Also, the effects of pisosterol on normal human cells were examined in peripheral blood mononuclear cells (PBMC). The effects on cell viability and morphological changes were the first indications showing that pisosterol induces HL-60 differentiation. The demonstration of blue tetrazolium reduction in HL-60 cells exposed to pisosterol demonstrated differentiation in a dose- and time-dependent manner, reaching a maximum effect after 72 h incubation at 5 microg/mL. Assays for alpha-naphthyl acetate esterase activity indicated that pisosterol triggers differentiation towards a monocytic cell-like pathway. The antiproliferative effect of pisosterol was determined by inhibition of DNA synthesis based on BrdU incorporation into HL-60 proliferating cells. It appears that pisosterol-treated cells, despite displaying a differentiated phenotype, continued to proliferate at all doses tested after 72 h, with a slightly decrease at 5 microg/mL. Apoptosis was observed in pisosterol-treated cells in a dose-dependent way. Nevertheless, after the same period of incubation, no cytotoxicity was detected in PBMC in the presence of pisosterol even at 25 microg/mL, providing some evidence that pisosterol may be selective for tumor cells. The mechanisms underlying the effect of pisosterol in leukemia cells indicates the induction of a monocytic cell-like differentiation, suggesting that this compound could be used in the development of new pharmacological tools with potential therapeutic value in the management of leukemia with fewer side effects.
Toxicology in Vitro 09/2007; 21(5):795-800. · 2.78 Impact Factor
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ABSTRACT: Part of our research program concentrates on the discovery of new bioactive compounds prepared either by total synthesis or molecular transformation of compounds with bioactivity profiles. In this work we have focused our interest on chemical transformations of the Diels-Alder adduct tricyclo[6.2.1.0(2,7)]undeca-4,9-dien-3,6-dione in order to obtain cage-like compounds and derivatives, followed by an evaluation of their biological activity.
Molecules 02/2007; 12(2):271-82. · 2.39 Impact Factor
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ABSTRACT: art of our research program concentrates on the discovery of new bioactivecompounds prepared either by total synthesis or molecular transformation of compoundswith bioactivity profiles. In this work we have focused our interest on chemicaltransformations of the Diels-Alder adduct tricyclo[6.2.1.02,7]undeca-4,9-dien-3,6-dione inorder to obtain cage-like compounds and derivatives, followed by an evaluation of theirbiological activity.
Molecules. 01/2007;
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ABSTRACT: Phytochemical analysis of the leaves of Acnistus arborescens (Solanaceae) resulted in the isolation of two new epimeric withaphysalins (17S,20R,22R)-5beta,6beta: 18,20-diepoxy-4beta,18-dihydroxy-1-oxowitha-24-enolide (2, 18R and 18S), together with the known withaphysalin F (1, 18R and 18S). Their structures were established by spectroscopic methods, including 2D NMR data and comparison with literature data. Compounds 1 and 2 dis-played potent cytotoxic activities against several cancer cell lines with IC50 values in the range of 0.20 to 1.46 microg/mL for 1 and 0.89 to 8.08 microg/mL for 2. The strong cytotoxicity presented by 1 suggests that in this series of compounds, the 2,3-unsaturated ketone moiety is an important pharmacophoric unit. The cytotoxic activity seemed to be related to DNA synthesis inhibition, as revealed by the reduction of 5-bromo-2'-deoxyuridine incorporation after 24 hours of incubation on leukemic cells.
Planta Medica 07/2004; 70(6):551-5. · 2.15 Impact Factor
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ABSTRACT: Pisolithus tinctorius (Basidiomycete) is an ectomicorrhizal fungus found in the roots and soil surrounding of many species of eucalyptus and pine trees. The present work verified the cytotoxic potential of pisosterol, a triterpene isolated from P. tinctorius collected in the Northeast region of Brazil, on three different animal cell models: mouse erythrocytes, sea urchin embryos and tumor cells. Pisosterol lacked activity on mouse erythrocytes as well as on the development of sea urchin eggs, but strongly inhibited the growth of all seven tumor cell lines tested, especially the leukemia and melanoma cells (IC50 of 1.55, 1.84 and 1.65 microg/ ml for CEM, HL-60 and B16, respectively). The results found for pisosterol were compared with those of doxorubicin and etoposide.
Zeitschrift fur Naturforschung C 59(7-8):519-22. · 0.77 Impact Factor
