Combining anti-cancer drugs with artificial sweeteners: Synthesis and anti-cancer activity of saccharinate (sac) and thiosaccharinate (tsac) complexes cis -[Pt(sac) 2 (NH 3 ) 2 ] and cis -[Pt(tsac) 2 (NH 3 ) 2 ]

Zn(ii), Cd(ii) and Hg(ii) saccharinate complexes with 2,6-bis(2-benzimidazolyl)pyridine as promising anticancer agents in breast and lung cancer cell lines via ROS-induced apoptosis

New Zn(ii), Cd(ii) and Hg(ii) complexes of saccharinate (sac) and 2,6-bis(2-benzimidazolyl)pyridine (bzimpy), [Zn(bzimpy)2](sac)2·2H2O (Zn), [Cd(sac)2(bzimpy)] (Cd) and [Hg(sac)2(bzimpy)] (Hg), were prepared and fully characterized by spectroscopic methods and X-ray crystallography. In vitro anticancer screening in A549 (lung), MCF-7 (breast) and HT29 (colon) cell lines showed that Zn was highly cytotoxic against A549 and MCF-7 cells with IC50 values of 1.74 ± 0.06 and 3.15 ± 0.10 μM, respectively, and Hg demonstrated potent cytotoxic activity in MCF-7 cells (8.61 ± 0.98 μM), while Cd and bzimpy exhibited moderate growth inhibitory activities in all of the cell lines. In addition, they showed significantly lower toxicity towards normal human breast epithelial MCF10A cells. Moreover, the complexes exhibited significantly high nuclease activity towards plasmid DNA and their interactions with DNA were assessed by gel electrophoresis and DNA docking. Zn and Hg induced G0/G1 cell arrest and apoptotic cell death detected via typical DNA condensation/fragmentation, annexin V staining and caspase 3/7 activity in A549 and MCF-7 cells. These complexes further caused depolarization of mitochondria and oxidative damage of genomic DNA following excessive production of reactive oxygen species (ROS).

Synthesis, characterization and crystal structures of platinum(II) saccharinate complexes with 1,5-cyclooctadiene

Two new platinum(II) complexes, namely [PtCl(sac)(COD)] (1) and [Pt(sac)₂(COD)] (2) (sac = saccharinate and COD = 1,5-cyclooctadiene), were synthesized and characterized by elemental analysis, IR, NMR, ESI-MS spectroscopic and thermal analysis (TG/DTA) methods. The platinum(II) complexes were prepared from the reaction of [PtCl₂(COD)] with Na(sac)•2H₂O. The addition of the sac ligand resulted in the replacement of 1 and 2 chlorido ligands in [PtCl₂(COD)] to yield 1 and 2, respectively. The structures of the complexes were determined by single crystal X-ray diffraction and showed a distorted square planar coordination geometry around platinum(II). COD acted as a π-donor ligand, while sac was N -coordinated in both complexes. The TG/DTA data indicated that both complexes were thermally stable up to 220 °C in air and their thermal decompositions yielded Pt as a final product. Complexes 1 and 2 were also designed as possible precursors to synthesize new mixed-ligand platinum(II) sac complexes in a one-pot reaction.

Structures and anticancer activity of chlorido platinum(II) saccharinate complexes with mono- and dialkylphenylphosphines

cis-[PtCl(sac)(PPh₂Me)₂] (1), cis-[PtCl(sac)(PPhMe₂)₂] (2), trans-[PtCl(sac)(PPh₂Et)₂] (3) and trans-[PtCl(sac)(PPhEt₂)₂] (4) complexes (sac = saccharinate) were synthesized and characterized by elemental analysis and spectroscopic methods. The structures of 2-4 were determined by X-ray single-crystal diffraction. The interaction of the complexes with DNA was studied various biochemical, biophysical and molecular docking methods. Only the cis-configured complexes (1 and 2) showed nuclease activity and their binding affinity towards DNA was considerably higher than those of their trans-congeners (3 and 4). The chlorido ligand in the cis-configured complexes underwent aquation, making them more reactive towards DNA. Furthermore, 1 and 2 exhibited anticancer potency on breast (MCF-7) and colon (HCT116) cancer cells similar to cisplatin, whereas 3 and 4 were biologicallly inactive. Mechanistic studies on MCF-7 cells showed that higher nuclear uptake, cell cycle arrest at the S phase, dramatically increased DNA double-strand breaks, apoptosis induction, elevated levels of reactive oxygen species (ROS) and high mitochondrial membrane depolarization greatly contribute to the anticancer potency of 1 and 2.

Palladium(ii) and platinum(ii) saccharinate complexes with bis(diphenylphosphino)methane/ethane: synthesis, S-phase arrest and ROS-mediated apoptosis in human colon cancer cells

New neutral [M(sac)2(diphos)] and cationic [M(diphos)2](sac)2 complexes, where M = PdII or PtII, sac = saccharinate, and diphos = 1,1-bis(diphenylphosphino)methane (dppm) or 1,2-bis(diphenylphosphino)ethane (dppe), were synthesized and structurally characterized. The anticancer activity of the complexes was investigated against MCF-7 (breast), A549 (lung), HCT116 (colon), DU145 (prostate) cancer and BEAS-2B (normal bronchial epithelial) cells. Neutral Pt-dppm (2) and Pd-dppe complexes (5) did not show any biological activity. The cationic Pd-dppe (7) complex displayed antiproliferative activity, while the rest of the complexes exhibited potent cytotoxicity compared with cisplatin. The active Pd(ii)/Pt(ii) complexes were then included in further studies including interaction with DNA/HSA, nuclease activity, cellular uptake and lipophilicity. The potent complexes induced the apoptotic cell death as probed through annexin V positivity and caspase activation. Mechanistic studies on HCT116 cells showed that the complexes cause cell cycle arrest at the DNA synthesis (S) phase and excessive generation of reactive oxygen species (ROS), damaging to both mitochondria and DNA.

In vitro evaluation of apoptotic effect of bis(acetylacetonato-k2 O,O')(1,10-phenanthroline-k2 N,N')Zn(II) complex

Phenanthroline derivatives have been reported as potential bioactive compounds because of their ability to interact with DNA. To evaluate the antiproliferative effect of bis(acetylacetonate-k² O,O)(1,10-phenanthroline-k² N,N)Zn(II) or Zn(acac)₂ (phen) complex, the compound was obtained in a simple manner and further characterized to determine crystal structure, thermal behavior, morphology, and spectroscopic properties. The structure of the complex was confirmed by X-ray single structure as well as by 1H and 13C nuclear magnetic resonance (NMR) in dmso-d6 (dimethyl sulfoxide) solution and in the solid state by 13C CP/MAS. Although preparation of this compound has been described previously, there are no reports on its biological activity; here, we assessed its antiproliferative effect on fibroblasts, A253, FaDu, Cal-27, RH-30, RD, U-373, C6, A-549, MDA-MB-231, and MCF-7 cancer cell lines at different doses (50-100 and 150 μg/ml). The cell viability was determined by MTT assay and high activity was observed for the most of the cell lines, and TUNEL results showed the induction of apoptosis.