One concept of improving anticancer effects of conventional platinum-based antitumor drugs consists of conjugating these compounds with other biologically (antitumor) active agents, acting by a different mechanism. Here, we present synthesis, physicochemical characterization, biological effects, and mechanisms of action of four new analogs of conventional cisplatin, namely, cis-Pt(II) complexes containing either methyl or ethyl pyrazole N-donor ligands and chlorido or iodido ligands. It is noteworthy that while chlorido complexes display activity in a variety of cancer cell lines comparable to cisplatin, iodido complexes are considerably more potent due to their enhanced hydrophobicity and consequently enhanced cellular accumulation. Moreover, all of the studied Pt(II) alkylpyrazole complexes display a higher selectivity for tumor cells and effectively overcome the acquired resistance to cisplatin. Further results focused on the mechanism of action of the studied complexes and showed that in contrast to cisplatin and several platinum-based antitumor drugs, DNA damage by the investigated Pt(II)-alkylpyrazole complexes does not play a major role in their mechanism of action. Our findings demonstrate that inhibition of the tubulin kinesin Eg5, which is essential for forming a functional mitotic spindle, plays an important role in their mechanism of antiproliferative action.

• Publikační typ
• časopisecké články MeSH

4-Azaindole (1H-pyrrolo[3,2-b]pyridine; 4aza) and its N1-alkylated derivative N1-isopropyl-4-azaindole (1-(propan-2-yl)-1H-pyrrolo[3,2-b]pyridine; ip4aza) have been used for the preparation of the cis-diiodido-platinum(II) complexes cis-[Pt(4aza)2I2] (1), cis-[PtI2(ip4aza)2] (2), cis-[Pt(4aza)I2(NH3)] (3) and cis-[PtI2(ip4aza)(NH3)] (4). The prepared complexes were thoroughly characterized (e.g., multinuclear NMR spectroscopy and ESI mass spectrometry) and their in vitro cytotoxicity was assessed at human ovarian carcinoma (A2780), cisplatin-resistant ovarian carcinoma (A2780R) and colon carcinoma (HT-29) cell lines, where they showed, in some cases, significantly higher activity than the used reference-drug cisplatin. The results of in vitro cytotoxicity testing at the A2780 and A2780R cells indicated that alkylation of the 4-azaindole moiety at the position of the N1 atom had a positive biological effect, because the ip4aza-containing complexes 2 and 4 showed significantly (p < 0.005) higher cytotoxicity than 4aza-containing analogues 1 and 3. The resistance factors (A2780R/A2780 model) equalled 0.8-1.4, indicating the ability of complexes 1-4 to overcome the acquired resistance of the A2780 cells against cisplatin. Complexes 1 and 2 revealed low toxicity against primary culture of human hepatocytes. The flow cytometry studies of the A2780 cell cycle modification showed that complexes 1-4 induce different cell cycle perturbations as compared with cisplatin, thus suggesting a different mechanism of their antitumor action.

• Klíčová slova
• 4-Azaindole, Cytotoxicity, In vitro, Iodido, Platinum(II) complexes,
• MeSH
• buněčný cyklus účinky léků   MeSH
• hydrofobní a hydrofilní interakce MeSH
• indoly chemie   farmakologie   MeSH
• lidé MeSH
• molekulární struktura MeSH
• nádorové buňky kultivované MeSH
• organoplatinové sloučeniny chemická syntéza   chemie   farmakologie   MeSH
• proliferace buněk účinky léků   MeSH
• protinádorové látky chemická syntéza   chemie   farmakologie   MeSH
• screeningové testy protinádorových léčiv MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 4-azaindole MeSH Prohlížeč
• indoly MeSH
• organoplatinové sloučeniny MeSH
• protinádorové látky MeSH

A series of gold(I) complexes of the general composition [Au(naza)(PPh₃)] (1-8) was prepared and thoroughly characterized (e.g., electrospray ionization (ESI) mass spectrometry and multinuclear nuclear magnetic resonance (NMR) spectroscopy). The N1-deprotonated anions of 7-azaindole or its derivatives (naza) are coordinated to the metal centre through the N1 atom of their pyrrole ring, as proved by a single crystal X-ray analysis of the complexes [Au(3I5Braza)(PPh₃)] (7) and [Au(2Me4Claza)(PPh₃)]·½H₂O (8'). The in vitrocytotoxicity of the complexes 1-8 was studied against both the cisplatin-sensitive and -resistant variants of the A2780 human ovarian carcinoma cell line, as well as against the MRC-5 human normal fibroblast cell line. The complexes 4, 5, and 8, containing deprotonated 3-iodo-7-azaindole, 5-bromo-7-azaindole, and 2-methyl-4-chloro-7-azaindole (2Me4Claza), respectively, showed significantly higher potency (IC50 = 2.8-3.5 µM) than cisplatin (IC50 = 20.3 µM) against the A2780 cells and markedly lower effect towards the MRC-5 non-cancerous cells (IC50 = 26.0-29.2 µM), as compared with the mentioned A2780 cancer cells. The results of the flow cytometric studies of the A2780 cell cycle perturbations revealed a G₂-cell cycle phase arrest of the cells treated by the representative complexes 1 and 5, which is indicative of a different mechanism of action from cisplatin (induced S-cell cycle phase arrest). The stability of the representative complex 8 in the water-containing solution as well as its ability to interact with the reduced glutathione, cysteine and bovine serum albumin was also studied using ¹H and 31P-NMR spectroscopy (studied in the 50% DMF-d₇/50% D₂O mixture) and ESI+ mass spectrometry (studied in the 50% DMF/50% H₂O mixture); DMF = dimethylformamide. The obtained results are indicative for the release of the N-donor azaindole-based ligand in the presence of the used biomolecules.

• Klíčová slova
• 7-azaindole, antitumor activity, crystal structures, gold(I) complexes, in vitro, triphenylphosphane,
• MeSH
• buněčná smrt účinky léků   MeSH
• buněčný cyklus účinky léků   MeSH
• fosfiny chemická syntéza   chemie   farmakologie   MeSH
• indoly chemická syntéza   chemie   farmakologie   MeSH
• krystalografie rentgenová MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• protinádorové látky farmakologie   MeSH
• protonová magnetická rezonanční spektroskopie MeSH
• voda chemie   MeSH
• zlato farmakologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• 7-azaindole dimer MeSH Prohlížeč
• fosfiny MeSH
• indoly MeSH
• protinádorové látky MeSH
• voda MeSH
• zlato MeSH

A series of platinum(II) diiodido complexes containing 7-azaindole derivatives, having the general formula cis-[PtI2(naza)2] (1-8), has been prepared and thoroughly characterized, including X-ray structure analysis of cis-[PtI2(2Me4Claza)2]∙DMF (8∙DMF; 2Me4Claza = 2-methyl-4-chloro-7-azaindole). Complexes showed high in vitro cytotoxicity against nine human cancer cell lines (IC50 ranging from 0.4 to 12.8 μM), including the cisplatin-resistant ovarian cancer cell line (A2780R; IC50 = 1.0-3.5 μM). The results of in vivo testing, using the L1210 lymphocytic leukaemia model, at the equimolar doses of Pt with cisplatin (2 mg/kg) confirmed the activity of complex 8 comparable to cisplatin. From the mechanistic point of view, evaluated ex vivo by Western blot analyses on the samples of isolated tumour tissues, the treatment of the animals with complex 8, contrary to cisplatin, decreased the levels of tumour suppressor p53 and increased significantly the amount of intracellular anti-apoptotic protein MCL-1L (37 kDa). Additionally, the active form of caspase 3 was significantly elevated in the sample of tumour tissues treated with complex 8, indicating that the activation of p53-independent cell-death pathway was initiated. The light and electron microscopy observations of the cancerous tissues revealed necrosis as a dominant mechanism of cell death, followed by scarce signs of apoptosis. The additional results (e.g. in vitro interaction experiments with selected biomolecules, cell cycle perturbations, gel electrophoretic studies on pUC19 plasmid DNA) supported the hypothesis that the complexes might be involved in the mechanism of action quite different from cisplatin.

• MeSH
• apoptóza účinky léků   MeSH
• buněčný cyklus účinky léků   MeSH
• chemorezistence účinky léků   MeSH
• cisplatina aplikace a dávkování   MeSH
• indoly aplikace a dávkování   chemie   MeSH
• kaspasa 3 genetika   MeSH
• lidé MeSH
• molekulární struktura MeSH
• nádorové buněčné linie MeSH
• nádorový supresorový protein p53 genetika   MeSH
• nádory vaječníků farmakoterapie   genetika   patologie   MeSH
• organoplatinové sloučeniny aplikace a dávkování   chemie   MeSH
• plazmidy účinky léků   MeSH
• proliferace buněk účinky léků   MeSH
• viabilita buněk účinky léků   MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• 7-azaindole dimer MeSH Prohlížeč
• cisplatina MeSH
• indoly MeSH
• kaspasa 3 MeSH
• nádorový supresorový protein p53 MeSH
• organoplatinové sloučeniny MeSH

The cis-[PtCl2(naza)2] complexes (1-3) containing monosubstituted 7-azaindole halogeno-derivatives (naza), showed significantly higher activity than cisplatin towards ovarian carcinoma A2780, its cisplatin-resistant variant A2780R, osteosarcoma HOS, breast carcinoma MCF7 and cervix carcinoma HeLa cell lines, with the IC50 values of 3.8, 3.5, 4.5, 2.7, and 9.2 μM, respectively, obtained for the most active complex 3. As for 4 and 5 having disubstituted 7-azaindoles in their molecule, the significant cytotoxicity was detected only for 4 against A2780 (IC50 = 4.8 μM), A2780R (IC50 = 3.8 μM) and HOS (IC50 = 4.3 μM), while 5 was evaluated as having only moderate antiproliferative effect against the mentioned cancer cell lines with IC50 = 33.4, 24.7 and 46.7 μM, respectively. All the studied complexes 1-5 effectively avoided the acquired resistance of ovarian carcinoma cell line. On the other hand, the complexes did not reveal any inhibition activity on the purified 20S proteasome from the A2780 cells. The representative complexes 3 and 5 showed low ability to be hydrolysed, but their stability was markedly lowered in the presence of physiological sulphur-containing biomolecule glutathione (GSH), as proved by the 1H NMR spectroscopy and mass spectrometry studies. A rate of interaction of the studied complexes with GSH was affected by an addition of another mechanistically relevant biomolecule guanosine monophosphate. The differences in interactions of 3 and 5 with GSH correlate well with their different cytotoxicity profiles.

• MeSH
• chemorezistence MeSH
• cisplatina chemie   farmakologie   MeSH
• glutathion chemie   MeSH
• HeLa buňky MeSH
• hmotnostní spektrometrie MeSH
• indoly chemie   farmakologie   MeSH
• lidé MeSH
• MFC-7 buňky MeSH
• molekulární struktura MeSH
• nukleární magnetická rezonance biomolekulární MeSH
• organoplatinové sloučeniny chemie   farmakologie   MeSH
• protinádorové látky chemie   farmakologie   MeSH
• viabilita buněk účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 7-azaindole dimer MeSH Prohlížeč
• cisplatina MeSH
• glutathion MeSH
• indoly MeSH
• organoplatinové sloučeniny MeSH
• protinádorové látky MeSH

The moderate-to-high in vitro cytotoxicity against ovarian A2780 (IC50 = 4.7-14.4 μM), prostate LNCaP (IC50 = 18.7-30.8 μM) and prostate PC-3 (IC50 = 17.6-42.3 μM) human cancer cell lines of the platinum(II) cyclobutane-1,1'-dicarboxylato complexes [Pt(cbdc)(naza)2] (1-6; cbdc = cyclobutane-1,1'-dicarboxylate(2-); naza = halogeno-substituted 7-azaindoles), derived from the anticancer metallodrug carboplatin, are reported. The complexes containing the chloro- and bromo-substituted 7-azaindoles (1, 2, and 4-6) showed a significantly higher (p < 0.05) cytotoxicity against A2780 cell line as compared to cisplatin used as a reference drug. Addition of the non-toxic concentration (5.0 μM) of L-buthionine sulfoximine (L-BSO, an effective inhibitor of γ-glutamylcysteine synthase) markedly increases the in vitro cytotoxicity of the selected complex 3 against A2780 cancer cell line by a factor of about 4.4. The cytotoxicity against A2780 and LNCaP cells, as well as the DNA platination, were effectively enhanced by UVA light irradiation (λmax = 365 nm) of the complexes, with the highest phototoxicity determined for compound 3, resulting in a 4-fold decline in the A2780 cells viability from 25.1% to 6.1%. The 1H NMR and ESI-MS experiments suggested that the complexes did not interact with glutathione as well as their ability to interact with guanosine monophosphate. The studies also confirmed UVA light induced the formation of the cis [Pt(H2O)2(cbdc`)(naza)] intermediate, where cbdc` represents monodentate-coordinated cbdc ligand, which is thought to be responsible for the enhanced cytotoxicity. This is further supported by the results of transcription mapping experiments showing that the studied complexes preferentially form the bifunctional adducts with DNA under UVA irradiation, in contrast to the formation of the less effective monofunctional adducts in dark.

• MeSH
• adukty DNA chemie   genetika   MeSH
• buthionin sulfoximin farmakologie   MeSH
• dvouřetězcové zlomy DNA účinky léků   účinky záření   MeSH
• hmotnostní spektrometrie s elektrosprejovou ionizací MeSH
• indoly chemie   farmakologie   MeSH
• karboplatina chemie   farmakologie   MeSH
• konformace nukleové kyseliny MeSH
• lidé MeSH
• molekulární struktura MeSH
• nádorové buněčné linie MeSH
• nádory genetika   patologie   MeSH
• protinádorové látky chemie   farmakologie   MeSH
• protonová magnetická rezonanční spektroskopie MeSH
• synergismus léků MeSH
• ultrafialové záření * MeSH
• viabilita buněk účinky léků   genetika   účinky záření   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 7-azaindole dimer MeSH Prohlížeč
• adukty DNA MeSH
• buthionin sulfoximin MeSH
• indoly MeSH
• karboplatina MeSH
• protinádorové látky MeSH

The in vitro antitumour activity studies on a panel of human cancer cell lines (A549, HeLa, G-361, A2780, and A2780R) and the combined in vivo and ex vivo antitumour testing on the L1210 lymphocytic leukaemia model were performed on the cis-[PtCl2(naza)2] complexes (1-3) involving the 7-azaindole derivatives (naza). The platinum(II) complexes showed significantly higher in vitro cytotoxic effects on cell-based models, as compared with cisplatin, and showed the ability to avoid the acquired resistance of the A2780R cell line to cisplatin. The in vivo testing of the complexes (applied at the same dose as cisplatin) revealed their positive effect on the reduction of cancerous tissues volume, even if it is lower than that of cisplatin, however, they also showed less serious adverse effects on the healthy tissues and the health status of the treated mice. The results of ex vivo assays revealed that the complexes 1-3 were able to modulate the levels of active forms of caspases 3 and 8, and the transcription factor p53, and thus activate the intrinsic (mitochondrial) pathway of apoptosis. The pharmacological observations were supported by both the histological and immunohistochemical evaluation of isolated cancerous tissues. The applicability of the prepared complexes and their fate in biological systems, characterized by the hydrolytic stability and the thermodynamic aspects of the interactions with cysteine, reduced glutathione, and human serum albumin were studied by the mass spectrometry and isothermal titration calorimetric experiments.

• MeSH
• cisplatina farmakologie   MeSH
• HeLa buňky MeSH
• hmotnostní spektrometrie s elektrosprejovou ionizací MeSH
• imunohistochemie MeSH
• indoly chemie   MeSH
• Kaplanův-Meierův odhad MeSH
• kaspasa 3 metabolismus   MeSH
• kaspasa 8 metabolismus   MeSH
• lidé MeSH
• lymfoidní leukemie farmakoterapie   patologie   MeSH
• magnetická rezonanční spektroskopie MeSH
• MFC-7 buňky MeSH
• molekulární struktura MeSH
• myši inbrední DBA MeSH
• nádorové buněčné linie MeSH
• nádorový supresorový protein p53 metabolismus   MeSH
• organoplatinové sloučeniny chemie   farmakologie   MeSH
• protinádorové látky chemie   farmakologie   MeSH
• stabilita léku MeSH
• termodynamika MeSH
• viabilita buněk účinky léků   MeSH
• výsledek terapie MeSH
• western blotting MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 7-azaindole dimer MeSH Prohlížeč
• cisplatina MeSH
• indoly MeSH
• kaspasa 3 MeSH
• kaspasa 8 MeSH
• nádorový supresorový protein p53 MeSH
• organoplatinové sloučeniny MeSH
• protinádorové látky MeSH

This study describes a one-pot synthesis of superparamagnetic maghemite-based 4-aminobenzoic acid-coated spherical core-shell nanoparticles (PABA@FeNPs) as suitable nanocomposites potentially usable as magnetic carriers for drug delivery. The PABA@FeNPs system was subsequently functionalized by the activated species (1* and 2*) of highly in vitro cytotoxic cis-[PtCl2(3Claza)2] (1; 3Claza stands for 3-chloro-7-azaindole) or cis-[PtCl2(5Braza)2] (2; 5Braza stands for 5-bromo-7-azaindole), which were prepared by a silver(I) ion assisted dechlorination of the parent dichlorido complexes. The products 1*@PABA@FeNPs and 2*@PABA@FeNPs, as well as an intermediate PABA@FeNPs, were characterized by a combination of various techniques, such as Mössbauer, FTIR and EDS spectroscopy, thermal analysis, SEM and TEM. The results showed that the products consist of well-dispersed maghemite-based nanoparticles of 13 nm average size that represent an easily obtainable system for delivery of highly cytotoxic cisplatin-like complexes in oncological practice.

• MeSH
• cisplatina aplikace a dávkování   chemie   MeSH
• indoly chemická syntéza   chemie   MeSH
• kyselina 4-aminobenzoová aplikace a dávkování   chemická syntéza   chemie   MeSH
• lékové transportní systémy * MeSH
• lidé MeSH
• nádory farmakoterapie   MeSH
• nanočástice chemie   MeSH
• nosiče léků chemická syntéza   chemie   MeSH
• protinádorové látky chemie   MeSH
• stříbro chemie   MeSH
• železité sloučeniny chemická syntéza   chemie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 7-azaindole dimer MeSH Prohlížeč
• cisplatina MeSH
• ferric oxide MeSH Prohlížeč
• indoly MeSH
• kyselina 4-aminobenzoová MeSH
• nosiče léků MeSH
• protinádorové látky MeSH
• stříbro MeSH
• železité sloučeniny MeSH