Recent advancements in DNA interaction studies of organotin(IV) complexes

Liposomal Formulations of Metallodrugs for Cancer Therapy

The search for new antineoplastic agents is imperative, as cancer remains one of the most preeminent causes of death worldwide. Since the discovery of the therapeutic potential of cisplatin, the study of metallodrugs in cancer chemotherapy acquired increasing interest. Starting from cisplatin derivatives, such as oxaliplatin and carboplatin, in the last years, different compounds were explored, employing different metal centers such as iron, ruthenium, gold, and palladium. Nonetheless, metallodrugs face several drawbacks, such as low water solubility, rapid clearance, and possible side toxicity. Encapsulation has emerged as a promising strategy to overcome these issues, providing both improved biocompatibility and protection of the payload from possible degradation in the biological environment. In this respect, liposomes, which are spherical vesicles characterized by an aqueous core surrounded by lipid bilayers, have proven to be ideal candidates due to their versatility. In fact, they can encapsulate both hydrophilic and hydrophobic drugs, are biocompatible, and their properties can be tuned to improve the selective delivery to tumour sites exploiting both passive and active targeting. In this review, we report the most recent findings on liposomal formulations of metallodrugs, with a focus on encapsulation techniques and the obtained biological results.

The Development of Organotin(IV) N-Ethyl-N-Benzyldithiocarbamate Complexes: A Study on Their Synthesis, Characterization, and Cytocidal Effects on A549 Cell Line

BACKGROUND

Organotin(IV) complexes of dithiocarbamate are vital in medicinal chemistry, exhibiting potential in targeting cancer cells due to their unique properties that enhance targeted delivery. This study aimed to synthesize and characterize organotin(IV) N-ethyl-N-benzyldithiocarbamate complexes (ONBDCs) and evaluate their cytotoxicity against A549 cells, which are commonly used as a model for human lung cancer research.

METHODS

The two ONBDC derivatives - ONBDC 1 (dimethyltin(IV) N-ethyl-N-benzyldithiocarbamate) and ONBDC 2 (triphenyltin(IV) N-ethyl-N-benzyldithiocarbamate) - were synthesized via the reaction of tin(IV) chloride with N-ethylbenzylamine in the presence of carbon disulfide. A range of analytical techniques, including elemental analysis, IR spectroscopy, NMR spectroscopy, UV-Vis spectrometry, TGA/DTA analysis, and X-ray crystallography, was conducted to characterize these compounds comprehensively. The cytotoxic effects of ONBDCs against A549 cells were evaluated using MTT assay.

RESULTS

Both compounds were synthesized and characterized successfully via elemental and spectroscopies analysis. MTT assay revealed that ONBDC 2 demonstrated remarkable cytotoxicity towards A549 cells, with an IC50 value of 0.52 μM. Additionally, ONBDC 2 displayed significantly higher cytotoxic activity against the A549 cell line when compared to the commercially available chemotherapeutic agent cisplatin (IC50: 32 μM).

CONCLUSION

Thus, it was shown that ONBDC 2 could have important anticancer properties and should be further explored as a top contender for creating improved and specialized cancer treatments.

Organotin (IV) Dithiocarbamate Compounds as Anticancer Agents: A Review of Syntheses and Cytotoxicity Studies

Organotin (IV) dithiocarbamate has recently received attention as a therapeutic agent among organotin (IV) compounds. The individual properties of the organotin (IV) and dithiocarbamate moieties in the hybrid complex form a synergy of action that stimulates increased biological activity. Organotin (IV) components have been shown to play a crucial role in cytotoxicity. The biological effects of organotin compounds are believed to be influenced by the number of Sn-C bonds and the number and nature of alkyl or aryl substituents within the organotin structure. Ligands target and react with molecules while preventing unwanted changes in the biomolecules. Organotin (IV) dithiocarbamate compounds have also been shown to have a broad range of cellular, biochemical, and molecular effects, with their toxicity largely determined by their structure. Continuing the investigation of the cytotoxicity of organotin (IV) dithiocarbamates, this mini-review delves into the appropriate method for synthesis and discusses the elemental and spectroscopic analyses and potential cytotoxic effects of these compounds from articles published since 2010.

What Can Electrochemical Methods Offer in Determining DNA-Drug Interactions?

The interactions of compounds with DNA have been studied since the recognition of the role of nucleic acid in organisms. The design of molecules which specifically interact with DNA sequences allows for the control of the gene expression. Determining the type and strength of such interaction is an indispensable element of pharmaceutical studies. Cognition of the therapeutic action mechanisms is particularly important for designing new drugs. Owing to their sensitivity, simplicity, and low costs, electrochemical methods are increasingly used for this type of research. Compared to other techniques, they require a small number of samples and are characterized by a high reliability. These methods can provide information about the type of interaction and the binding strength, as well as the damage caused by biologically active molecules targeting the cellular DNA. This review paper summarizes the various electrochemical approaches used for the study of the interactions between pharmaceuticals and DNA. The main focus is on the papers from the last decade, with particular attention on the voltammetric techniques. The most preferred experimental approaches, the electrode materials and the new methods of modification are presented. The data on the detection ranges, the binding modes and the binding constant values of pharmaceuticals are summarized. Both the importance of the presented research and the importance of future prospects are discussed.

Organotin derivatives of cholic acid induce apoptosis into breast cancer cells and interfere with mitochondrion; Synthesis, characterization and biological evaluation

Organotin(IV) derivatives of cholic acid (CAH) with the formulae R3Sn(CA) (R = Ph- (1), n-Bu- (2)) and R2Sn(CA)2 (R = Ph- (3), n-Bu- (4) and Me- (5)) were synthesized. The compounds were characterized in solid state by melting point, FT-IR, 119Sn Mössbauer, X-ray fluorescence (XRF) spectroscopy and in solution by 1H NMR, UV-Vis spectral data and by Electrospray Ionisation Mass spectrometry (ESI-MS), High Resolution Mass spectrometry (HRMS), and atomic absorption analysis. The in vitro bioactivity of 1-5 against human breast adenocarcinoma cancer cells MCF-7 (positive to hormone receptors) and MDA-MB-231 (negative to hormone receptors) reveal that triorganotin derivatives 1-2 exhibit significantly stronger activity than the corresponding diorganotin ones. Compound 5 is inactive against both cell lines at the concentrations tested. Triorganotins 1-2 inhibit selectively MCF-7 than MDA-MB-231 cells, suggesting hormone mimetic behavior of them. Organotins 1-4 inhibit both cancerous cell lines, stronger than cisplatin which rise up to 55-fold against MCF-7 and 170-fold against MDA-MB-231. The in vitro toxicity of 1-4 was evaluated on normal human fetal lung fibroblast cells (MRC-5), while their genotoxicity in vitro by micronucleus assay (MN). Moreover, the in vivo toxicity of 1-4 was tested by Artemia salina assay and their in vivo genotoxicity with Allium cepa test. The mechanism of action of 1-4 against MCF-7 was clarified in vitro by the means of cell morphology studies, cell cycle arrest, Acridine Orange/Ethidium Bromide (AO/EB) Staining, mitochondrial membrane permeabilization test and by their binding affinity toward the calf thymus (CT) DNA.

Multispectroscopic analysis, atomic force microscopy, molecular docking and molecular dynamic simulation studies of the interaction between [SnMe2Cl2(Me2phen)] complex and ct-DNA in the presence of glucose

In this study, the spectroscopic methods (UV-vis, fluorimetric), Atomic force microscopy, and computational studies (molecular docking and molecular dynamic simulation) were used to investigate the interaction of [SnMe₂Cl₂(Me₂phen)] complex with CT-DNA in the presence of glucose. The results showed the complex in the medium containing glucose has less effect on calf thymus DNA (ct-DNA) than the medium without glucose. Cytotoxicity of [SnMe₂Cl₂(Me₂phen)] complex on MCF-7 cells was examined and showed Sn(IV) complex possesses potential cytotoxicity against this cell line. Molecular docking study showed that Sn(IV) complex interacts with DNA by groove binding mode. Radius of gyration (Rg) was smaller upon binding of the Sn(IV) complex suggesting a more compact structure of DNA in the presence of Sn(IV) complex.Communicated by Ramaswamy H. Sarma.

Dibutyltin(IV) and Tributyltin(IV) Derivatives of meso-Tetra(4-sulfonatophenyl)porphine Inhibit the Growth and the Migration of Human Melanoma Cells

Melanoma is the most aggressive and deadly form of skin cancer, which is largely due to its propensity to metastasize. Therefore, with the aim to inhibit the growth and the metastatic dissemination of melanoma cells and to provide a novel treatment option, we studied the effects of the melanoma treatment with two organotin(IV) complexes of the meso-tetra(4-sulfonato-phenyl)porphine, namely (Bu2Sn)2TPPS and (Bu3Sn)4TPPS. In particular, we showed that nanomolar concentrations of (Bu2Sn)2TPPS and (Bu3Sn)4TPPS are sufficient to inhibit melanoma cell growth, to increase the expression of the full-length poly (ADP-ribose) polymerase (PARP-1), to induce the cell cycle arrest respectively at G2/M and G0/G1 through the inhibition of the Cyclin D1 expression and to inhibit cell colony formation. Nanomolar concentrations of (Bu2Sn)2TPPS and (Bu3Sn)4TPPS are also sufficient to inhibit the melanoma cell migration and the expression of some adhesion receptors. Moreover, we report that (Bu2Sn)2TPPS and (Bu3Sn)4TPPS act downstream of BRAF, mainly bypassing its functions, but targeting the STAT3 signalling protein. Finally, these results suggest that (Bu2Sn)2TPPS and (Bu3Sn)4TPPS may be effective therapeutic strategies for their role in the inhibition of melanoma growth and migration.

Studies on the Interaction of [SnMe2Cl2(bu2bpy)] Complex with ct-DNA Using Multispectroscopic, Atomic Force Microscopy (AFM) and Molecular Docking

The interaction of SnMe₂Cl₂(bu₂bpy)complex with calf thymus DNA (ct-DNA) has been explored following, using spectroscopic methods, viscosity measurements, Atomic force microscopy, Thermal denaturation and Molecular docking. It was found that Sn(IV) complex could bind with DNA via intercalation mode as evidenced by hyperchromism and bathochromic in UV-Vis spectrum; these spectral characteristics suggest that the Sn(IV) complex interacts with DNA most likely through a mode that involves a stacking interaction between the aromatic chromophore and the base pairs of DNA. In addition, the fluorescence emission spectra of intercalated methylene blue (MB) with increasing concentrations of SnMe₂Cl₂(bu₂bpy) represented a significant increase of MB intensity as to release MB from MB-DNA system. Positive values of ΔH and ΔS imply that the complex is bound to ct-DNA mainly via the hydrophobic attraction. Large complexes contain the DNA chains with an average size of 859 nm were observed by using AFM for Sn(IV) Complex-DNA. The Fourier transform infrared study showed a major interaction of Sn(IV) complex with G-C and A-T base pairs and a minor perturbation of the backbone PO₂ group. Addition of the Sn(IV)complex results in a noticeable rise in the Tm of DNA. In addition, the results of viscosity measurements suggest that SnMe₂Cl₂(bu₂bpy) complex may bind with the classical intercalative mode. From spectroscopic and hydrodynamic studies, it has been found that Sn(IV)complex interacts with DNA by intercalation mode. Optimized docked model of DNA-complex mixture confirmed the experimental results.