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Mauro Coluccia

Publications and source records attributed to Mauro Coluccia.

6 recordsLinked to original sources

Sterically hindered complexes of platinum(II) with planar heterocyclic nitrogen donors. A novel complex with 1-methyl-cytosine has a spectrum of activity different from cisplatin and is able of overcoming acquired cisplatin resistance.

A very interesting series of water soluble platinum compounds violating some of the classical structure-activity relationships, but still showing antitumor activity, was reported by Hollis and collaborators some 25 years ago [L.S. Hollis, A.R. Amundsenm, E.W. Stern. J. Med. Chem. 32 (1989) 128-136]. The compounds, having formula [PtClA(2)L](+) (A(2)=two monodentate or a bidentate amine, L=a secondary or tertiary amine or a N-donor heterocycle), were characterized by a positive charge and three non-labile N-donor ligands. We have extended the investigation to analogous compounds in which 2,9-dimethyl-1,10-phenanthroline has taken the place of the A(2) ligand(s) and L is 2-picoline (1), 6-amino-2-picoline (2), or 1-methyl-cytosine (3). The X-ray analysis of 2 has revealed a bow-like distortion of the phenanthroline plane, a sloping of the phenanthroline plane with respect to the coordination plane, and an overall shielding of the metallic core by the ortho substituents of the phenanthroline and pyridine ligands. In vitro grow inhibition assays have been performed on the most water soluble complex 3. The results indicate that this complex is characterized by a potent growth inhibitory activity with mean IC(50) value (in a panel of 11 human tumor cell lines) of 1.1 microM to be compared with a mean value of 3.8 microM for cisplatin. The same compound also appears to completely overcome the acquired cisplatin resistance stemming from reduced uptake or a multifocal mechanism, thus pointing to a mechanism of action distinctly different from that of cisplatin.

Antineoplastic Agents↗

Differential processing of antitumour-active and antitumour-inactive trans platinum compounds by SKOV-3 ovarian cancer cells.

In order to compare the mechanistic properties of the antitumour-active trans platinum complex trans-[PtCl(2){Z-HN=C(OMe)Me}(NH(3))] (trans-Z) and of the antitumour-inactive isomer of cisplatin trans-[PtCl(2)(NH(3))(2)] (trans-DDP), the differential processing of the two compounds by SKOV-3 ovarian cancer cells has been investigated. trans-Z and trans-DDP enter cells with the same efficacy, but trans-Z shows a two-fold higher affinity for cellular DNA. The treatment with trans-DDP IC(50) determines an initial and transient cytostatic effect, paralleled by a moderate increase of apoptosis and by sequential and reversible arrests in S and G(2)/M phases of cell-cycle. In contrast, trans-Z IC(50) determines an initial cytotoxic effect, a more persistent and marked increase of apoptosis, and a more marked and prolonged arrest in S and G(2)/M phases of the cell-cycle. Treatment-induced gene expression modifications indicate that phenotypic effects of trans-DDP are driven by an initial and transient up-regulation of some genes related to cell-cycle checkpoint and arrest networks, whereas the more dramatic phenotypic effects of trans-Z are driven by a persistent up-regulation of more numerous genes involved in cell-cycle checkpoint and arrest networks, and in genome stability and DNA repair. Therefore, molecular and cellular events have been identified which are produced by trans-Z but not by trans-DDP, and which likely represent the mechanistic basis of antitumour activity of trans-Z in the SKOV-3 system.

Animals↗

Synthesis and in vitro antitumor activity of platinum acetonimine complexes.

The cis- and trans-dichloro- and diiodo-platinum(II) complexes containing two acetonimines (cis- and trans-[PtX(2){HN=C(CH(3))(2)}(2)], 1 and 2 for X = Cl and 1' and 2' for X = I, respectively) or one acetonimine and one ammine (cis- and trans-[PtX(2)(NH(3)){HN=C(CH(3))(2)}], 3 and 4 for X = Cl and 3' and 4' for X = I, respectively) have been prepared from platinum-ammine precursors by condensation with acetone. Except for the cis-diiodo species, in all other cases the presence of a base was required. A crucial role of the ligand trans to the ammine undergoing condensation with acetone has been disclosed: the greater the trans effect the greater the reactivity. In a panel of human tumor cell lines representative of ovarian, colon, lung, and breast cancers, cis complexes 1 and 3 are less active than cis-DDP (mean IC(50) = 20, 12.5, and 2.8 microM, respectively), whereas trans complexes 2 and 4 are more active than trans-DDP (mean IC(50) = 10.6, 26, and 164 microM, respectively), thus indicating that substitution of acetonimine for one or two ammine ligands determines strikingly different effects depending upon the complex geometry.

Antineoplastic Agents↗

Platinum complexes with imino ethers or cyclic ligands mimicking imino ethers: synthesis, in vitro antitumour activity, and DNA interaction properties.

Both trans- and cis-[PtCl(2)(NH(3))(L)] compounds have been synthesized, L representing either the imino ether HN=C(OMe)Me having a Z or E configuration at the C=N double bond, or the cyclic ligands N = C(OMe)CH2CH2CH2 and N = C(Me)OCH2CH2 (compounds 1-4 for trans geometry and 5-8 for cis geometry, respectively). The cyclic ligands mimic the imino ether ligands but, differently from imino ethers, cannot undergo change of configuration. In a panel of human tumor cells, trans compounds inhibit growth much more than transplatin. Moreover, compound 1 in most cases is less active than 2, and 1 and 2 are less active than 3 and 4, respectively. For cis compounds with imino ethers, the activity is reduced (5) or unaffected (6) with respect to cisplatin. Moreover, unlike trans compounds, substitution of cyclic ligands (7,8) for imino ethers (5,6) generally decreases the activity. This determines, for compounds with cyclic ligands, an unusual inversion of the cis geometry requirement for activity of platinum(II) species. Importantly,1-4 and 5-8 partially circumvent the multifocal cisplatin resistance of A2780cisR cells, and 1-4 also overcome resistance from reduced uptake of 41McisR cells. DNA interaction regioselectivity of 1-4 and 5-8 is not substantially modified with respect to transplatin and cisplatin. However, both imino ethers and cyclic ligands slow down the DNA interstrand cross-link reaction, ( E)-HN=C(OMe)Me and N = C(Me)OCH2CH2 decreasing also its extent. Therefore, DNA interaction of 1-4 and 5-8 appears to be characterized by persistent monoadducts (1-4), and by monoadducts and/or intrastrand cross-links structurally different from those of cisplatin (5-8). This study demonstrates that ligand configuration modulates the activity of both trans and cis compounds, and supports the development of platinum drugs based on their coordination chemistry to combat cisplatin resistance.

Antineoplastic Agents↗

Endothelial cells in the bone marrow of patients with multiple myeloma.

Endothelial cells (EC) were extracted through a lectin-based method from bone marrow of 57 patients with active multiple myeloma (MM) and compared with their healthy quiescent counterpart, human umbilical vein EC (HUVEC). MMECs exhibit specific antigens that indicate ongoing angiogenesis and embryo vasculogenesis; solid intercellular connections, hence stability of MM neovessels; and frequent interactions with plasma cells, hence tumor dissemination. They show heterogeneous antigen expression, hence existence of subsets. Their main genetic markers are indicative of a vascular phase. They show intrinsic angiogenic ability, because they rapidly form a capillary network in vitro, and extrinsic ability, because they generate numerous new vessels in vivo. They vividly secrete growth and invasive factors for plasma cells. They signal through kinases mandatory for development of neovascularization. Ultrastructurally, they are abnormal and show metabolic activation, like tumor ECs. Thalidomide heavily interferes with their functions. Vasculogenesis and angiogenesis might contribute to the MM vascular tree and progression, in the form of growth, invasion, and dissemination. In view of the heterogeneity of the antigenic phenotype of MMECs, a mixture (or a sequence) of antiangiogenic agents coupled with thalidomide would seem plausible for the biologic management of MM.

Aged↗