Apoptosis-inducing, anti-angiogenic and anti-migratory effects of a dinuclear Pd(II) complex on breast cancer: A promising novel compound

Because of the high mortality and morbidity rate of breast cancer, successful management of the disease requires synthesis of novel compounds. To this end, ongoing attempts to create new candidates include synthesis of multinuclear metal complexes. The high DNA binding affinity and cytotoxic activity of these complexes makes them promising as breast cancer treatments. This study investigated anti-growth/cytotoxic effect of the dinuclear Pd(II) complex on breast cancer cell lines (MCF-7, MDA-MB-231) using various methods of staining, flow cytometry, and immunoblotting. The study conducted colony formation, invasion, and migration assays were to assess the effect of the complex on metastasis. Increased caspase-3/7 levels and positive annexin V staining were observed in both cell lines, proving apoptosis. Altered TNFR1 and TRADD expression with caspase-8 cleavage followed by BCL-2 inactivation with loss of mitochondrial membrane potential confirmed the presence of apoptosis in MCF-7 and MDA-MB-231, regardless of p53 expression status. The results implied anti-migration properties. Finally, the study used the CAM assay to assess antiangiogenic properties and showed that the complex inhibited angiogenesis. The study concluded the dinuclear Pd(II) complex warrants further in vivo experiments to show its potential in the treatment of breast cancer.

Synthesis, Structure and Photoluminescence Properties of Cd and Cd-Ln Pentafluorobenzoates with 2,2′:6′,2′-Terpyridine Derivatives

Six new complexes [Cd(tpy)(pfb)2] (1, tpy = 2,2′:6′,2″-terpyridine), [Ln2Cd2(tpy)2(pfb)10] (Ln = Eu (2Eu), Tb (2Tb)), [Ln2Cd2(tbtpy)2(pfb)10]·2MeCN (Ln = Eu (3Eu), Tb (3Tb), tbtpy = 4,4′,4″-tri-tert-butyl-2,2′:6′,2″-terpyridine), [Eu2Cd2(tppz)(pfb)10]n (4, tppz = 2,3,5,6-tetra-(pyridin-2-yl)pyrazine) based on pentafluorobenzoic acid (Hpfb) have been prepared and investigated. The effect of tridentate ligands on geometry heterometallic scaffolds synthesized complexes is discussed. The supramolecular crystal structures of the new compounds are stabilized by π-π, C-F···π, C-H···O, C-H...F, F….F interactions. Non-covalent interactions have been studied using Hirschfeld surface analysis. The obtained compounds were characterized by single-crystal and powder X-ray diffraction, luminescence spectroscopy, IR spectroscopy, CHN analysis. Complexes 2Ln and 3Ln exhibit metal-centered photoluminescence, but the presence of ligand luminescence bands indicates incomplete energy transfer from the d-block to the lanthanide ion.

Syntheses, crystal structures, and biological evaluations of new dinuclear platinum(ii) complexes with 1,2,4-triazole derivatives as bridging ligands

A series of new dinuclear platinum(ii) complexes with the general formula [Pt₂(μ-HL)₄] (1-4), where H₂L is 4-[(5-chloro-2-hydroxy-benzylidene)-amino]-3-R-1,2,4-triazole-5-thione: R = H (1), methyl (2), ethyl (3) and propyl (4), were synthesized and characterized. The X-ray crystal structures of 2, 3 and 4 reveal that the two platinum atoms form a paddlewheel core with four chelating triazole ligands as bridges, revealing a radically different structure than those of the traditional anticancer platinum(ii) complexes. These complexes show higher in vitro antiproliferative activity against human liver hepatocellular carcinoma (HepG2) and human breast adenocarcinoma (MCF7) than human lung cancer (A549) and human normal hepatocyte (HL-7702) cell lines. In particular, 3 exhibits antiproliferative activity (IC₅₀ = 5.5 μM) against HepG2 cells comparable to that of cisplatin. Different from the traditional anticancer platinum(ii) complexes with high DNA affinity, 3 binds very weakly to DNA. Upon comparison, it exhibits potent inhibiting activity against protein tyrosine phosphatases 1B (PTP1B, IC₅₀ = 16 μM) through possible binding to its active sites and its binding constant is 5.28 × 10⁴ M^-1. The results suggest that the antiproliferative mechanism of 3 against HepG2 cells may be different from that of cisplatin.

Highly Promising Antitumor Agent of a Novel Platinum(II) Complex Bearing a Tetradentate Chelating Ligand

A new mononuclear cationic platinum(II) coordination compound with 6,6'-bis(NH-benzimidazol-2-yl)-2,2'-bipyridine (L) ligand having N₄-tetradentate binding pocket [Pt(L)]Cl₂·2H₂O (Complex 1) was synthesized and characterized by FT-IR(ATR), UV-vis, ¹H NMR, APCI and MALDI MS, and CHN analysis. The antigrowth effect of Complex 1 was tested in breast cancer (MDA-MB-231), lung cancer (A549), colorectal cancer (HCT-116), prostate cancer (PC-3) cell lines, and bronchial epithelial cell line (BEAS-2B) by the SRB and ATP cell viability assays. Apoptosis was detected with Annexin V, mitopotential, BCL-2 inactivation, and γH2AX assays by flow cytometry. Complex 1 was found to have cytotoxic activity of MDA-MB-231, A549, HCT-116, and PC-3 cancer cell lines in a dose-dependent manner for 48 h. Complex 1 has been found to cause cell death through different mechanisms depending on the type of cancer. The findings indicated that complex induced intrinsic apoptosis with the increased mitochondrial membrane depolarization level, Bcl-2 inactivation, and DNA damage in PC-3 and A549 cell lines.

High-performance liquid chromatography associated with resonance Rayleigh scattering spectral study of the interactions of palladium(ii)–antimigraine chelates with Erythrosin B and their analytical applications

For the first time, a highly sensitive and selective detection technology of high-performance liquid chromatography associated with resonance Rayleigh scattering spectra (HPLC-RRS) is applied to analyze migraine drugs including zolmitriptan (ZON) and rizatriptan (RIN).

Crystal and mol-ecular structures of a binuclear mixed ligand complex of silver(I) with thio-cyanate and 1H-1,2,4-triazole-5(4H)-thione

The complete mol-ecule of the binuclear title complex, bis-[μ-1H-1,2,4-triazole-5(4H)-thione-κ2 S:S]bis-{(thio-cyanato-κS)[1H-1,2,4-triazole-5(4H)-thione-κS]silver(I)}, [Ag2(SCN)2(C2H3N3S)4], is generated by crystallographic inversion symmetry. The independent triazole-3-thione ligands employ the exocyclic-S atoms exclusively in coordination. One acts as a terminal S-ligand and the other in a bidentate (μ2) bridging mode to provide a link between two AgI centres. Each AgI atom is also coordinated by a terminal S-bound thio-cyanate ligand, resulting in a distorted AgS4 tetra-hedral coordination geometry. An intra-molecular N-H⋯S(thio-cyanate) hydrogen bond is noted. In the crystal, amine-N-H⋯S(thione), N-H⋯N(triazol-yl) and N-H⋯N(thio-cyanate) hydrogen bonds give rise to a three-dimensional architecture. The packing is consolidated by triazolyl-C-H⋯S(thio-cyanate), triazolyl-C-H⋯N(thiocyanate) and S⋯S [3.2463 (9) Å] inter-actions as well as face-to-face π-π stacking between the independent triazolyl rings [inter-centroid separation = 3.4444 (15) Å]. An analysis of the calculated Hirshfeld surfaces shows the three major contributors are due to N⋯H/H⋯N, S⋯H/H⋯S and C⋯H/H⋯C contacts, at 35.8, 19.4 and 12.7%, respectively; H⋯H contacts contribute only 7.6% to the overall surface.