New adamantane phenylalkylamines with σ-receptor binding affinity and anticancer activity, associated with putative antagonism of neuropathic pain.

The synthesis of the adamantane phenylalkylamines 2a-d, 3a-c, and 4a-e is described. These compounds exhibited significant antiproliferative activity, in vitro, against eight cancer cell lines tested. The σ(1), σ(2), and sodium channel binding affinities of compounds 2a, 3a, 4a, and 4c-e were investigated. The most interesting analogue, 4a, exhibited significant in vivo anticancer profile on pancreas, prostate, leukemia, and ovarian cancer cell line xenografts together with apoptosis and caspase-3 activation. Inhibition of the cancer cells cycle at the sub-G1 level was also obtained with 4a. Finally, encouraging results were observed with 4a in vivo on mice, suggesting putative antimetastatic and analgesic activities of this compound.

Implications of pleiotrophin in human PC3 prostate cancer cell growth in vivo.

Pleiotrophin (PTN) is a heparin-binding growth factor with diverse functions related to tumor growth, angiogenesis, and metastasis. Pleiotrophin seems to have a significant role in prostate cancer cell growth and to mediate the stimulatory actions of other factors that affect prostate cancer cell functions. However, all studies carried out up to date are in vitro, using different types of human prostate cancer cell lines. The aim of the present work was to study the role of endogenous PTN in human prostate cancer growth in vivo. For this purpose, human prostate cancer PC3 cells were stably transfected with a plasmid vector, bearing the antisense PTN sequence, in order to inhibit PTN expression (AS-PC3). Migration, apoptosis, and adhesion on osteoblastic cells were measured in vitro. In vivo, PC3 cells were s.c. injected into male NOD/SCID mice, and tumor growth, survival rates, angiogenesis, apoptosis, and the number of metastasis were estimated. Pleiotrophin depletion resulted in a decreased migration capability of AS-PC3 cells compared with the corresponding mock-transfected or the non-transfected PC3 cells, as well as increased apoptosis and decreased adhesiveness to osteoblastic cells in vitro. In prostate cancer NOD/SCID mouse xenografts, PTN depletion significantly suppressed tumor growth and angiogenesis and induced apoptosis of cancer cells. In addition, PTN depletion decreased the number of metastases, providing a survival benefit for the animals bearing AS-PC3 xenografts. Our data suggest that PTN is implicated in human prostate cancer growth in vivo and could be considered a potential target for the development of new therapeutic approaches for prostate cancer.

Synthesis, σ1, σ2-receptors binding affinity and antiproliferative action of new C1-substituted adamantanes.

The synthesis of N-{4-[a-(1-adamantyl)benzyl]phenyl}piperazines 2a-e is described. The in vitro antiproliferative activity of most compounds against main cancer cell lines is significant. The σ(1), σ(2)-receptors and sodium channels binding affinity of compounds 2 were investigated. One of the most active analogs, 2a, had an interesting in vivo anticancer profile against the BxPC-3 and Mia-Paca-2 pancreas cancer cell lines with caspase-3 activation, which was associated with an anagelsic activity against the neuropathic pain.

New adamantane derivatives with sigma affinity and antiproliferative activity.

The synthesis of 4-(1-adamantyl)-4,4-diarylbutylamines 1, 5-(1-adamantyl)-5,5-diarylpentylamines 2 and 6-(1-adamantyl)-6,6-diarylhexylamines 3 is described and the σ1, σ2-receptors and sodium channels binding affinity of compounds 1 were investigated. The in vitro activity of compounds 1, 2 and 3 against main cancer cell lines is significant. One of the most active analogs, 1a, had an interesting in vivo anticancer profile against the ovarian cancer cell line IGROV-1, which was associated with an anagelsic activity against the neuropathic pain induced by the main anticancer drugs.

Sesquiterpene lactones from Anthemis melanolepis and their antibacterial and cytotoxic activities. Prediction of their pharmacokinetic profile.

Nine sesquiterpene lactones, anthemin A (1), 1alpha-hydroxydeacetylirinol-4alpha,5beta-epoxide (2), anthemin C (3), tatridin A (4), 1-epi-tatridin B (5), anthemin B (6), 6-deacetyl-beta-cyclopyrethrosin (7), elegalactone A (8), and 1beta,4alpha,6alpha-trihydroxyeudesm-11-en-8alpha-12-olide (9), were isolated from the aerial parts of A. melanolepis in addition to eight known flavonoids and three phenolic acids. Compounds 1, 3, and 6 are new natural products. The structures of the compounds were deduced by spectroscopic methods. The in vitro antimicrobial potential of the isolated sesquiterpene lactones against four Gram-positive and five Gram-negative bacteria and one fungus was evaluated using the microdilution method, and their in vitro cytotoxic activity was determined against a panel of human tumor cell lines. Furthermore, the pharmacokinetic profile of the sesquiterpene lactones was investigated using computational methods.

Design and development of liposomes incorporating a bioactive labdane-type diterpene. In vitro growth inhibiting and cytotoxic activity against human cancer cell lines.

The isolation and identification of bioactive compounds from natural sources has given insights in the discovery of new drugs against several diseases. Labdane-type diterpenes isolated from nature, have been investigated in the past for their pharmaceutical activities. Labd-7,13-dien-15-ol (1), a major lipophilic constituent of the resin 'ladano' was found to exhibit cytotoxic and cytostatic activity against cell lines derived from solid tumors with a profound activity on small lung cancer cells, DMS114. The present study, based on liposomal technology, aimed to develop a suitable carrier of compound 1 to overcome its water insolubility that inhibits further in vivo administration. Liposomes have been proved adequate drug carriers which enhance the solubility of water insoluble drugs and reduce possible side effects. Dipalmitoyl phosphatidylcholine (DPPC), egg phosphatidylcholine (EPC) and dipalmitoyl phosphatidylglycerol (DPPG) were used to prepare liposomes incorporating compound 1 at various molar ratios. Their physicochemical characteristics were determined and liposomes composed of EPC:DPPG 9:0.1 (molar ratio) was chosen as the most suitable carrier concerning their physical characteristics, stability, incorporation efficiency as well as the ability to retain the capture of compound 1 in the presence of RPMI-1640 medium. The activity of the liposomal formulation of compound 1 against human cancer cell lines was compared to that of its free form. The results showed that EPC:DPPG:1 9:0.1:5 (molar ratio) liposomal formulation maintained the pharmacological activity of 1, improved its water solubility and was justified as suitable formulation for in vivo administration of compound 1.

Sesquiterpene lactones from Centaurea spinosa and their antibacterial and cytotoxic activities.

Ten sesquiterpene lactones, 8alpha-O-(3,4-dihydroxy-2-methylenebutanoyloxy)sonchucarpolide (4-epi-malacitanolide) (1), 8alpha-O-(4-acetoxy-2-hydroxymethylbuten-2-oyloxy)-4-epi-sonchucarpolide (2), malacitanolide (3), its 4'-acetyl derivative (4), 8alpha-O-(3,4-dihydroxy-2-methylenebutanoyloxy)dehydromelitensine (5), 8alpha-O-(3,4-dihydroxy-2-methylenebutanoyloxy)-15-oxo-5,7alphaH,6betaH-eleman-1,3,11(13)-trien-6,12-olide (6), the germacranolides 8alpha-O-(4-acetoxy-2-hydroxymethylbuten-2-oyloxy)salonitenolide (7), cnicin (8), and 4'-acetylcnicin (9), and the sesquiterpene methyl 8alpha-O-(3,4-dihydroxy-2-methylenebutanoyloxy)-6alpha,15-dihydroxyelema-1,3,11(13)-trien-12-oate (10), were isolated from the aerial parts of Centaurea spinosa. Nine known flavonoids were also isolated. The structures and the stereochemistry of the new compounds 1 and 2 were deduced by spectroscopic methods. The in vitro activity of 1-10 against three Gram-positive and three Gram-negative bacteria was evaluated using a microdilution method, and their in vitro cytotoxic activity was determined against a panel of human tumor cell lines.

Labdane-type diterpenes: thermal effects on phospholipid bilayers, incorporation into liposomes and biological activity.

Labd-13(E)-ene-8alpha,15-diol (1) and its derivative labd-13(E)-ene-8alpha-ol-15-yl-acetate (2) are water insoluble biological active molecules and their structures were elucidated using NMR and X-ray techniques. Differential scanning calorimetry (DSC) was applied to study the thermal effects of 1 and 2 on DPPC bilayers. Liposomes composed of egg phosphatidylcholine/dipalmytoylphosphatidylglycerol (9:0.1 molar ratio) were prepared by the thin-film hydration method and were used for incorporating 1 and 2. Free and liposomal 1 and 2 were tested for their activity against human cancer cell lines using the sulphorhodamine B assay. The effect of 1 and 2 on DPPC bilayers caused abolition of the pre-transition temperature, lowering of the main phase transition and reduction of the transition enthalpy only in the presence of cholesterol. The liposomes that have been designed and developed offer high incorporation efficiency; 62.4% (0.369 drug/lipid molar ratio) and 99.7% (0.661 drug/lipid molar ratio) for 1 and 2, respectively. Liposomal 2 showed growth-inhibiting activity against the majority of the tested cell lines.

Doxorubicin-PAMAM dendrimer complex attached to liposomes: cytotoxic studies against human cancer cell lines.

Liposomes composed of HePC:EPC:SA 10:10:0.1 (molar ratio) (1) and EPC:SA 10:0.1 (molar ratio) (2) were prepared and were used for incorporating the doxorubicin-PAMAM complex (3:1 molar ratio) (3). The doxorubicin-PAMAM complex was attached to liposomes and the incorporation efficiency was 91 and 95% for 1 and 2, respectively. The incorporation efficiency for doxorubicin into PAMAM was almost 97% while doxorubicin to PAMAM molar ratio was 3.56+/-0.04. The release rate of doxorubicin as doxorubicin-PAMAM complex from liposomes 1 and 2 and from the complex 3, was studied using buffers and 50% RPMI cell culture medium at 37 and 25 degrees C. The low release rate of doxorubicin as well as the high incorporation efficiency of doxorubicin-PAMAM complex into liposomes are considered as beneficial factors concerning the activity of doxorubicin. The cytotoxic activity of the liposomal formulation 1 incorporating doxorubicin-PAMAM complex, based on doxorubicin activity, was compared to that of 2 incorporating doxorubicin-PAMAM complex and to that of 3. The results showed that complex 1 was the most active formulation against all cancer cell lines compared to that of 2 and 3. Liposomal formulations composed of lipids and of a drug-dendrimer complex could be characterized as modulatory liposomal controlled release system (MLCRS), and could provide benefits to the delivery of drugs and modulate their release.

Liposomal formulations from phospholipids of Greek almond oil. Properties and biological activity.

The seeds of the almond tree [(Prunus dulcis (Mill.) D. A. Webb. (syn. Prunus amygdalus)] were collected in two different periods of maturity and were studied for their lipid content. The total lipids (TL) were extracted by the Bligh-Dyer method and the lipid classes have been isolated by chromatographic techniques and were analyzed by HPTLC coupled with a flame ionization detector (HPTLC/FID) and GC-MS. The oils were found to be rich in neutral lipids (89.9% and 96.3% of total lipids) and low in polar lipids (10.1% and 3.7% of total lipids) for the immature and mature seed oils, respectively. The neutral lipid fraction consisted mainly of triacylglycerides whereas the polar lipids mainly consisted of phospholipids. GC-MS data showed that the main fatty acid for both oils was 9-octadecenoic acid (oleic acid). The unsaturated fatty acids were found as high as 89.4% and 89.7%, while the percentage of the saturated fatty acids was found 10.6% and 10.3% for the immature and mature seed oils, respectively. Liposomes were prepared from the isolated phospholipids using the thin lipid film methodology, and their physical properties were characterized. Cytotoxicity was found absent when assayed against normal and cancerous cell lines. These new formulations may have future applications for encapsulation and delivery of drugs and cosmetically active ingredients.

Bioactive sesquiterpene lactones from Centaurea species and their cytotoxic/cytostatic activity against human cell lines in vitro.

Sesquiterpene lactones isolated from the aerial parts of various species of the genus Centaurea were examined for their in vitro cytotoxic/cytostatic activity against five human cell lines (i. e., DLD1, SF268, MCF7, H460 and OVCAR3). Compounds 1 - 4 were isolated from C. zuccariniana, 5 and 6 from C. achaia, 7 from C. thessala ssp. drakiensis and compounds 8 and 9 from C. deusta. Compound 1, 8alpha- O-(3,4-dihydroxy-2-methylenebutanoyloxy)dehydromelitensine was found to be the most active, exhibited a considerable growth inhibiting activity against three of the cell lines tested, while compound 5 8alpha- O-(3-hydroxy-2-methylenepropanoyl)dehydromelitensin exhibited a growth inhibiting effect against most of the tested cell lines. A new eudesmanolide (8alpha-hydroxysonchucarpolide, 4) was isolated from C. zuccariniana and its structure was elucidated by spectroscopic methods.

New 2-(1-adamantylcarbonyl)pyridine and 1-acetyladamantane thiosemicarbazones-thiocarbonohydrazones: cell growth inhibitory, antiviral and antimicrobial activity evaluation.

The new thiosemicarbazones and thiocarbonohydrazones derived from 2-(1-adamantylcarbonyl)pyridine and 1-acetyladamantane were synthesized and evaluated for their inhibitory effect on tumor cell proliferation and their antiviral and antimicrobial activity. Thiosemicarbazone inhibited tumor cell proliferation (GI50's range: 2.4-100 microM and mean GI50 43.9 microM against various human leukemic cell lines) while thiosemicarbazone and thiocarbonohydrazone 5d exhibited significant inhibition of tumor cell proliferation (GI50's range 2.3-23.6 microM and mean GI50 7.2 microM for and GI50's range 2.4-32.4 microM and mean GI50 12.8microM for ). These GI50 values are comparable to that of 2-acetylpyridine thiosemicarbazone an important lead in TSC's family. The compounds did not afford specific activity against any of the viruses tested when examined at non-toxic concentrations. A weak activity was found for thiocarbonohydrazones against Gram-(+) bacteria (MIC(50) 117.3 and 133 microM, respectively). Using a combination of molecular mechanics calculations and NOE spectroscopy it was shown that the parent compounds and have opposite configuration around C=N bond. Whether this difference in structure can be correlated with the biological activity will be investigated in future studies.