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M Coluccia

Publications and source records attributed to M Coluccia.

At least 19 recordsLinked to original sources
PubMed2002

Inhibition of endothelial cell functions and of angiogenesis by the metastasis inhibitor NAMI-A.

NAMI-A is a ruthenium-based compound with selective anti-metastasis activity in experimental models of solid tumours. We studied whether this activity was dependent on anti-angiogenic ability of NAMI-A. We thus investigated its in vitro effects on endothelial cell functions necessary for angiogenesis to develop, as well as its in vivo effects in the chick embryo chorioallantoic membrane model. Endothelial cell proliferation, chemotaxis, and secretion of the matrix-degrading enzyme metalloproteinase-2 were inhibited by NAMI-A in a dose-dependent manner, and without morphologic signs of cell apoptosis or necrosis. Lastly, NAMI-A displayed a dose-dependent in vivo anti-angiogenic activity in the chorioallantoic membrane model. These data suggest that the anti-angiogenic activity of NAMI-A can contribute to its anti-metastatic efficacy in mice bearing malignant solid tumours.

Angiogenesis Inhibitors↗
PubMed2000

Synthesis, crystal structure, spectral properties and cytotoxic activity of platinum(II) complexes of 2-acetyl pyridine and pyridine-2-carbaldehyde N(4)-ethyl-thiosemicarbazones.

The reactions of Na2PtCl4 with pyridine-2-carbaldehyde and 2-acetyl pyridine N(4)-ethyl-thiosemicarbazones, HFo4Et and HAc4Et respectively, afforded the complexes [Pt(Fo4Et)Cl], [Pt(HFo4Et)2]Cl2, [Pt(Fo4Et)2] and [Pt(Ac4Et)Cl], [Pt(HAc4Et)2]Cl2 x 2H2O, [Pt(Ac4Et)2]. The new complexes have been characterized by elemental analyses and spectroscopic studies. The crystal structure of the complex [Pt(Ac4Et)Cl] has been solved. The anion of Ac4E coordinates in a planar conformation to the central platinum(II) through the pyridyl N, azomethine N and thiolato S atoms. Intermolecular hydrogen, non-hydrogen bonds, pi-pi and weak Pt-pi contacts lead to aggregation and a supramolecular assembly. The cytotoxic activity for the platinum(II) complexes in comparison to that of cisplatin and thiosemicarbazones was evaluated in a pair of cisplatin-sensitive and -resistant ovarian cancer cell lines A2780 and A2780/Cp8. The platinum(II) complexes showed a cytotoxic potency in a very low micromolar range and were found able to overcome the cisplatin resistance of A2780/Cp8 cells.

Cell Division↗
PubMed2000

Antimetastatic properties and DNA interactions of the novel class of dimeric Ru(III) compounds Na2[[trans-RuCl4(Me2SO)]2(mu-L)] (L = ditopic, non-chelating aromatic N-ligand). A preliminary investigation.

A novel class of dianionic Ru(III) dimers of formula Na2[[trans-RuCl4(Me2SO)]2(mu-L)], with L = pyrazine (pyz, 1), pyrimidine (pym, 2), 4,4'-bipyridine (bipy, 3), and 1,2-bis(4-pyridine) ethane (etbipy, 4), was developed by us with the specific aim of assessing their antitumor properties. The dimers are in fact structurally related to the antimetastatic mononuclear compound (ImH) [trans-RuCl4(Me2SO)(Im)] (NAMI-A, Im = imidazole). Preliminary results concerning the antineoplastic activity of 1-4 against the murine MCa carcinoma model, a tumor which spontaneously metastasizes in the lungs, are reported. Similarly to what is normally observed with NAMI-A, the treatment with the dimeric complexes was scarcely effective against the growth of the primary tumor. However, dimers 1, 2, and 4 reduced very effectively the number and, in particular, the weight of lung metastases (to about 5% with respect to controls); in particular, Na2[[trans-RuCl4(Me2SO)]2(mu-etbipy)] (4) was as effective as NAMI-A in reducing the spontaneous metastases at a dosage which, in terms of moles of ruthenium, is about 3.5 times lower compared to that normally used for NAMI-A. Furthermore, in vitro tests showed that dimers 1-4 are capable of forming interstrand cross-links with linearized plasmidic DNA in a time-dependent manner. All the dimeric species are more active in inducing cross-links compared to NAMI-A, and the dimer bridged by the etbipy ligand (4) is the most effective among those tested.

Animals↗
PubMed2000

Replacement of an NH(3) by an iminoether in transplatin makes an antitumor drug from an inactive compound.

To investigate the modifications of antitumor activity and DNA binding mode of transplatin after replacement of one nonleaving group NH(3) by an iminoether group, trans-[PtCl(2)(Z-HN=C(OMe)Me)(NH(3)] and trans-[PtCl(2)(E-HN=C(OMe)Me)(NH(3)] complexes (differing in the Z or E configuration of iminoether, and abbreviated mixed Z and mixed E, respectively), have been synthesized. In a panel of human tumor cell lines, both mixed Z and mixed E show a cytotoxic potency higher than that of transplatin, the mean IC(50) values being 103, 37, and 215 microM, respectively. In vivo mixed Z is more active and less toxic than mixed E in murine P388 leukemia and retains its efficacy against SK-OV-3 human cancer cell xenograft in nude mice. In the reaction with naked DNA, mixed Z forms monofunctional adducts that do not evolve into intrastrand cross-links but close slowly into interstrand cross-links between complementary guanine and cytosine residues. The monofunctional mixed Z adducts are removed by thiourea and glutathione. The interstrand cross-links behave as hinge joints, increasing the flexibility of DNA double helix. The mixed Z, transplatin, and cisplatin interstrand cross-links, as well as mixed Z monofunctional adducts are not specifically recognized by HMG1 protein, which was confirmed to be able to specifically recognize cisplatin d(GpG) intrastrand cross-links. These data demonstrate that the DNA interaction properties of the antitumor-active mixed Z are very similar to those of transplatin, thus suggesting that clinical inactivity of transplatin could not depend upon its peculiar DNA binding mode.

Animals↗
PubMed1999

In vitro and in vivo antitumour activity and cellular pharmacological properties of new platinum-iminoether complexes with different configuration at the iminoether ligands.

In order to widen our knowledge on antitumour trans-[PtCl2(iminoether)2] complexes, we have synthesised two new derivatives, trans-[PtCl2¿E-HN = C(OEt)Me¿2] (1) and trans-[PtCl2¿Z-HN = C(OEt)Me¿2] (2), which differ in the configuration of the iminoether ligands. Isomer 1 showed an in vitro cytotoxicity similar to that of cisplatin in a panel of human tumour cell lines (mean IC50 = 8 and 7.7 microM, respectively), whereas isomer 2 showed a lower activity (IC50 = 14.3 microM). Both 1 and 2 isomers overcame cisplatin resistance of ovarian cancer cell line A2780/Cp8. In agreement with the n-octanol/saline partition ratios, intracellular platinum content (and DNA platination) after a 2-h exposure to equimolar drug concentrations was in the order 1 > 2 >> cisplatin, thus indicating that substitution of imminoethers for ammines determines a major lipophilicity and cellular uptake of the platinum drug. Both 1 and 2 showed a major toxic effect towards an excision repair-defective Drosophila strain, thus indicating cellular DNA as cytotoxic target. Finally, both 1 and 2 were active in vivo against the murine P388 system, but, contrary to the in vitro activity, isomer 2 was slightly more active than 1. On the whole, the results confirm the antitumour activity of trans-[PtCl2(iminoether)2] complexes, and indicate that the configuration of the iminoether ligands may affect the pharmacological properties of this class of complexes.

Animals↗
PubMed1999

In vitro antitumour activity and cellular pharmacological properties of the platinum-iminoether complex trans-[PtCl2[E-HN=C(OMe)Me]2].

The platinum complex trans-[PtCl2¿E-HN=C(OMe)Me¿2] was compared to cisplatin for cytotoxicity towards tumour cells, and for cellular pharmacological properties in A2780 and cisplatin-resistant A2780/Cp8 ovarian cancer cells. Trans-[PtCl2¿E-HN=C(OMe)Me¿2] was comparably cytotoxic to cisplatin (mean IC50 after 72 h exposure = 6. 1 microM and 7 microM, respectively) and did not show cross-resistance in A2780/Cp8 cells (resistance factor = 0.9). Cellular accumulation measurements after treatment with equimolar drug concentrations showed that trans-[PtCl2¿E-HN=C(OMe)Me¿2] entered both A2780 and A2780/Cp8 cells much more efficiently than cisplatin, whose accumulation was reduced in A2780/Cp8 cells. Unlike cisplatin, trans-[PtCl2¿E-HN=C(OMe)Me¿2] induced rapidly cell death and cell cycle modifications of treated cells, thus indicating substantially different mechanistic properties.

Antineoplastic Agents↗
PubMed1999

Cytotoxicity and DNA binding mode of new platinum-iminoether derivatives with different configuration at the iminoether ligands.

The platinum-iminoether complexes trans-[PtCl2[E - HN = C(OEt)Me]2] (1) and trans-[PtCl2[Z - HN = C(OEt)Me[2] (2), differing in the configuration of the iminoether ligands, were investigated for cytotoxicity towards human tumor cell lines, the involvement of DNA as a cytotoxic target, and their DNA binding mode. The cytotoxicity of isomer 1 was comparable to that of cisplatin, whereas isomer 2 was slightly less active. Excision-repair-deficient xeroderma pigmentosum group A cells were four times more sensitive to both isomers than normal cells, thus implicating cellular DNA as the cytotoxic target. Replication mapping experiments showed that both isomers interact preferentially with guanine residues at py-G-py sites. Oligodeoxyribonucleotides containing unique N7-guanine monofunctional adducts of the more cytotoxic isomer 1 were prepared and investigated for chemical reactivity, stability and DNA conformational alterations. The results showed that the ability of thiourea to labilize the monofunctional adducts depends upon the DNA secondary structure, but not upon the sequence context. Monofunctional adducts evolve to bidentate adducts in single-stranded oligonucleotides, but they are stable in double-stranded oligonucleotides and produce conformational distortions selectively located at the 5'-adjacent base pair. This study gives new insight into the mechanism of action of trans platinum-iminoether complexes, enabling for the first time comparison between different ligand isomers.

Antineoplastic Agents↗
PubMed1997

DNA modifications by antitumor trans-[PtCl2(E-iminoether)2].

Recent findings that an analogue of clinically ineffective transplatin, trans-[PtCl2(E-iminoether)2], exhibits antitumor activity has helped reevaluation of the empirical structure-antitumor activity relationship generally accepted for platinum(II) complexes. According to this relationship, only the cis geometry of leaving ligands in the bifunctional platinum(II) complexes, should be therapeutically active. Global modifications of natural DNAs in cell-free media by trans-[PtCl2(E-iminoether)2] were studied through various molecular biophysical methods and compared with modifications by cis-[PtCl2(E-iminoether)2], transplatin, cisplatin, and monofunctional chlorodiethylenetriamineplatinum(II) chloride. Thus, the results of this study have extended our recent finding, indicating that the prevalent lesion occurring in double-helical DNA on its modification by trans-[PtCl2(E-iminoether)2] is a monofunctional adduct at guanine residues. The modification by trans-[PtCl2(E-iminoether)2] has been found to induce local distortions in DNA, which have a character differing fundamentally from those induced by both clinically ineffective or antitumor platinum complexes tested in this study. The different character of alterations induced in DNA by the adducts of trans-[PtCl2(E-iminoether)2] and transplatin has been suggested to be relevant to the unexpected observation that the new complex with leaving chloride groups in trans position exhibits antitumor efficacy. In addition, the results support the idea that platinum drugs that bind to DNA in a manner fundamentally different from that of cisplatin can exhibit altered biological properties, including differing spectra and intensities of antitumor activity.

Animals↗
PubMed1996

DNA adducts of antitumor trans-[PtCl2 (E-imino ether)2].

It has been shown recently that some analogues of clinically ineffective trans-diamminedichloroplatinum (II) (transplatin) exhibit antitumor activity. This finding has inverted the empirical structure-antitumor activity relationships delineated for platinum(II) complexes, according to which only the cis geometry of leaving ligands in the bifunctional platinum complexes is therapeutically active. As a result, interactions of trans platinum compounds with DNA, which is the main pharmacological target of platinum anticancer drugs, are of great interest. The present paper describes the DNA binding of antitumor trans-[PtCl(2)(E-imino ether)(2)] complex (trans-EE) in a cell-free medium, which has been investigated using three experimental approaches. They involve thiourea as a probe of monofunctional DNA adducts of platinum (II) complexes with two leaving ligands in the trans configuration, ethidium bromide as a probe for distinguishing between monofunctional and bifunctional DNA adducts of platinum complexes and HPLC analysis of the platinated DNA enzymatically digested to nucleosides. The results show that bifunctional trans-EE preferentially forms monofunctional adducts at guanine residues in double-helical DNA even when DNA is incubated with the platinum complex for a relatively long time (48 h at 37 degrees C in 10 mM NaCIO(4). It implies that antitumor trans-EE modifies DNA in a different way than clinically ineffective transplatin, which forms prevalent amount of bifunctional DNA adducts after 48 h. This result has been interpreted to mean that the major adduct of trans-EE, occurring in DNA even after long reaction times, is a monofunctional adduct in which the reactivity of the second leaving group is markedly reduced. It has been suggested that the different properties of the adducts formed on DNA by transplatin and trans-EE are relevant to their distinct clinical efficacy.

Animals↗
PubMed1995

Platinum(II) complexes containing iminoethers: a trans platinum antitumour agent.

The biological activity of cis and trans complexes of formula [PtCl2(HN = C(OMe)Me)2] has been investigated. The iminoether ligands can have either E or Z configuration about the C = N double bond, therefore EE, EZ and ZZ isomers are obtainable. Substitution of iminoether with EE configuration for amine leads to unexpectedly high antitumor activity for the complex with trans geometry which turns out to be more active than the cis congener in the P388 leukaemia system. The same trans-EE complex shows an activity comparable to that of cisplatin in reducing the primary tumour mass and lung metastases in mice bearing Lewis lung carcinoma, thus representing a trans platinum complex active on both limphoproliferative and solid metastasizing murine tumours. Also the cytotoxicity, the inhibition of DNA synthesis and the mutagenic activity, which are greater for the cis- with respect to the trans-isomer in the amine complexes, are instead greater for the trans- than for the cis- isomer in the case of iminoether compounds. Binding to calf thymus DNA is slower for iminoether complexes than it is for amine complexes, however after 24 h reaction time the level of binding is similar for both types of complexes. Trans-EE, like trans-DDP, does not give the DNA conformational alterations (terbium fluorescence) typical of antitumour-active cis- platinum compounds, but, under strictly analogous experimental conditions, shows a greatly reduced DNA interstrand cross-linking ability (heat denaturation/renaturation assay) with respect to either trans-DDP or cis-EE and cis-DDP. The data in hand point to a new trans platinum antitumour complex with a mechanism of action different from that of cis-DDP and classical analogues.

Animals↗
PubMed1993

Anti-leukaemic action of RuCl2 (DMSO)4 isomers and prevention of brain involvement on P388 leukaemia and on P388/DDP subline.

Two ruthenium(II) complexes, characterised by the presence of dimethylsulphoxide ligands, were investigated in comparison to cisplatin on mouse P388 leukaemia and on a subline made resistant to cisplatin (P388/DDP). Both cis- and trans-RuCl2(DMSO)4 significantly prolonged the survival time of leukaemic mice, independently of the tumour line used. Unlike cisplatin, the prolongation of life-span of tumour-bearing hosts caused by ruthenium complexes was not supported by a parallel inhibition of the number of tumour cells in the treated hosts, as evidenced by tumour cell count in the peritoneal cavity and by vivo-vivo bioassays of blood samples and of whole brains. Thus, cis- and trans-RuCl2(DMSO)4 appear capable of preventing leukaemic spread into the central nervous system also when the number of tumour cells in the peritoneal cavity and in the blood stream is as high as in untreated controls. When the drug-induced DNA damage was investigated by modifying double stranded DNA and identifying the lesions able to inhibit DNA synthesis in vitro, trans-RuCl2(DMSO)4 and, to a lesser extent, cis-RuCl2(DMSO)4 formed blocking lesions at the same sites of cisplatin; nevertheless, the mechanism of antitumour activity of ruthenium complexes appears to be different from that of cisplatin for the absence of any relationship between cytotoxicity and prevention of leukaemic dissemination into the central nervous system. These data indicate that the activity of cis- and trans-RuCl2(DMSO)4 on the P388 leukaemia is characterised by the lack of cross-resistance with cisplatin and by the alteration of the metastasising behaviour of leukaemic cells which lose their natural capacity to invade the central nervous system.

Animals↗
PubMed1988

Treatment with cyclosporin A does not affect macrophage procoagulant activity and plasminogen activator inhibitor in mice.

Using a mouse model, we have investigated the in vivo effect of cyclosporin on macrophage procoagulant activity and on plasma levels of plasminogen activator inhibitor. Procoagulant activity of peritoneal macrophages was studied after treatment of mice with different regimens of cyclosporin (10 to 100 mg/kg body weight) for seven days. No significant difference was found between treated and control animals in both basal procoagulant activity and procoagulant activity generated during short-term culture in the absence or in the presence of endotoxin. These findings are in striking contrast with in vitro experiments showing that cyclosporin induced a significant increase in procoagulant activity when added to peritoneal macrophages from normal animals before challenge with endotoxin (p less than 0.01). Plasma levels of plasminogen activator inhibitor in cyclosporin-treated mice were not different from those of controls. It is suggested that factors other than monocyte-macrophage procoagulant activity or plasminogen activator inhibitor may be important for the postulated 'prothrombotic' action of cyclosporin.

Animals↗
PubMed1985

In vitro cisplatin effects on phagocyte functions.

The effects of cis-diamminedichloroplatinum (II) (cisplatin), a drug used in cancer chemotherapy, on the oxidative metabolism, endocytosis, chemotaxis and exocytosis of guinea-pig polymorphonuclear leukocytes were studied. All these functions were negatively influenced, but the same effect (50% inhibition) was observed at different drug concentrations (3 X 10(-5) M for chemotaxis, 10(-4) M for O2 consumption by FMLP and beta-glucuronidase release, 10(-3) M for O2 consumption by PMA and for zymosan engulfment). The effects of the drug can be explained by its ability to bind to membrane proteins, essentially to -SH groups.

Animals↗
PubMedDate not supplied

Interaction of RuCl2 (dimethylsulphoxide)4 isomers with DNA.

A wide series of restriction enzymes with a range of specificities was used to investigate the interaction with DNA of Ru(II)-DMSO complexes with anticancer activity. While cis-RuCl2 (DMSO)4 was almost completely inactive, treatment of pBR 322 DNA with trans-RuCl2 (DMSO)4 protected G rich sequences from cutting of specific restriction endonucleases, indicating a preferential interaction with adjacent guanines.

Base Sequence↗
PubMedDate not supplied

Synthesis, mutagenicity, binding to pBR 322 DNA and antitumour activity of platinum(II) complexes with ethambutol.

Platinum complexes with N,N'-bis(1-hydroxybut-2-yl)ethylenediamine, [PtCl2(ethambutol)] were prepared and the biological activity of three isomers [with (-), (+) and (+/-) ethambutol, respectively] investigated. All species interact with the Bam HI and Ava I recognition sequences showing a binding preference for GC rich sequences of DNA. The complex which showed the greatest interaction with adjacent guanines, [PtCl2[+/-)ethambutol)] was also found to be the most mutagenic of the three. On the other hand, only [PtCl2[+)ethambutol)] had a considerable antitumour activity against both P388 leukaemia and Lewis lung carcinoma, and this was not correlated either with restriction enzyme blocking activity or with mutagenicity.

Animals↗