Property evaluation of two anticancer candidate platinum complexes with N-isobutyl glycine ligand against human colon cancer

Quantum mechanical approaches and molecular docking studies of platinum based anticancer drugs Satraplatin and picoplatin structures

The structures of the anticancer drug compounds satraplatin and picoplatin are optimized, and theoretical studies done by Density Functional Theory (DFT) to investigate the optical properties, global chemical descriptors, and band gap were calculated using the obtained Frontier molecular orbital values. The theoretically obtained data of the platinum drugs found to possess low energy gap values and low chemical hardness with high chemical softness describe that the compounds are chemically stable and most reactive. Using the molecular docking process, the binding mechanisms of the satraplatin and picoplatin drugs with cancer DNA structures were studied, and the results were analyzed. For the two drug compounds examined, satraplatin has shown the least binding energies at -5.06kcal/mol compared to picoplatin at -2.69 kcal/mol, and conformations with root mean square deviation (RMSD) values by DNA structures are less than or equal to 2.00 Å in targeting the specific DNA target residues of the reference bound ligand. The grid box was generated using the selective grid parameters using the Autodock 4.2 program. The drug molecules found to have the least binding energy value with the lowest inhibition constant implicate the good docking score towards the DNA structure by the docking studies. DFT studies also show good structural properties and chemical reactivity. From the obtained results, satraplatin and picoplatin were found to have good chemical descriptors and good binding affinity and are best suited for biological molecular targets.

Effect of geometric isomerism on the anticancer property of new platinum complexes with glycine derivatives as asymmetric N, O donate ligands against human cancer

In this project, to fallow the anticancer ability of new Pt drugs, several new Pt complexes were synthesized with the asymmetric bidentate glycine derivatives, as named propyl- and hexyl glycine (L), in the general formula: [Pt(NH3)2(L)]NO3, and cis- and trans-[Pt(L)2]. The structure of two cis- and trans-[Pt(propylgly)2] complexes was proved by single crystallography analysis. However, all complex structures were characterized by various methods of 1H NMR, 13C NMR, 195Pt NMR, FTIR, LC-Mass, and Raman spectroscopy. To study the passage of water-soluble complexes of [Pt(NH3)2(L)]NO3 via cell membrane, their solubility, and lipophilicity were analyzed. In addition, the cytotoxic properties of these complexes were evaluated against normal and malignant cell lines (skin, breast, and lung cancer cells). The results indicated that they were either comparable to cisplatin or less damaging than carboplatin and oxaliplatin. It was expected that due to less steric effect, and the presence of length aliphatic hydrocarbon chain in the complex structure, trans-[Pt(hexylgly)2] is more toxic on cancerous cell lines than trans-[Pt(propylgly)2]. Cellular accumulation of all complexes was evaluated on A549 and MCF7 cell lines, and the amount of platinum metal (ng) was measured by the ICP method. Results showed that trans-[Pt(hexylgly)2] complex has the highest accumulation inside both mentioned cell lines and [Pt(NH3)2(L)]NO3 complexes behave like clinical Pt-drugs. Ultimately, the interaction patterns of DNA were examined using spectroscopic methods and molecular docking simulations for all substances.

Platinum (II) complex of isopentyl glycine ligand: DNA binding, molecular dynamic, and anticancer activity against breast cancer

In this paper, we performed thorough experimental and theoretical calculations to examine the interaction between Pt derivative, as an anticancer, and ct-DNA. The mode of DNA binding with [Pt(NH3)2(Isopentylgly)]NO3, where Isopentylgly is Isopentyl glycine, was evaluated by various spectroscopic methods, docking, and molecular dynamics simulation studies. UV-Vis and fluorescence spectroscopic titration results and CD spectra of DNA-drug showed this interaction is via groove binding. Also, thermal stability studies or DNA melting temperature changes (ΔTm), as well as the quenching emissions monitoring proved it. Also, the thermodynamic parameter and binding constant displayed that complex-DNA formation is a spontaneous process, and H-binding and also groove binding were found to be the main forces. Theoretical studies stated [Pt(NH3)2(Isopentylgly)]NO3-DNA formation occurs on C-G center on DNA, along with rising DNA-compound stability. IC50 value against the human breast cell line probably is due to the Isopentyl glycine ligand in the structure of the Pt compound, and it was obtained more than cisplatin and less than carboplatin against the MCF7 cell.Communicated by Ramaswamy H. Sarma.

Structure-bioactivity relationship study on anticancer Pd and Pt complexes with aliphatic glycine derivative ligands

To investigate the structure and bioactivity relationship, six Pd(II)/Pt(II) complexes with N-isobutylglycine (L1) and cyclohexylglycine (L2) as N^O amino acid bidentate ligands, 1,10'-phenanthroline (phen) and 2,2'-bipyridine (bipy) as N^N donor ligands, and [Pd(L1)(bipy)]NO3 (1), [Pd(L2)(bipy)]NO3 (2), [Pd(L1)(phen)]NO3 (3), [Pd(L2)(phen)]NO3·2H2O (4), [Pt(L1)(phen)]NO3 (5), along with [Pt(L2)(phen)]NO3 (6) were prepared and then characterized. The geometry of each compound was validated by doing a DFT calculation. Furthermore, tests were conducted on the complexes' water solubilities and lipophilicity. All bipy complexes had superior aqueous solubility and less lipophilicity in comparison with phen complexes, as well as complexes containing cyclohexyl-glycine compared to isobutyl-glycine complexes, probably because of the steric effects and polarity of cyclohexylglycine. The in-vitro anticancer activities of these compounds were examined against HCT116, A549, and MCF7 cancerous cell lines. Data revealed that all Pd/Pt complexes demonstrate higher anticancer activity than carboplatin, and complexes 3 and 4 are more cytotoxic than cisplatin against the HCT116 cell line, particularly against MCF7 cancerous cells. In addition, among all compounds, complex 4 has more anticancer ability than oxaliplatin. Due to different solubility and lipophilicity behavior, the accumulation of Pt complexes and clinical Pt drugs in each cancerous cell was investigated. The binding capabilities of these complexes to DNA, as the main target in chemotherapy, occur through minor grooves and intercalate into DNA, which was done using absorption, fluorescence, and circular dichroism spectroscopy. Finally, the docking simulation study showed the mode of DNA bindings is in good agreement with the spectral binding data.

Biological interaction of Pt complex with imidazole derivative as an anticancer compound with DNA: Experimental and theoretical studies

This investigation is applied to find out interesting information on DNA binding mode with Pt(II) derivative of two N, N bidentate ligands in treating cancer. Thus, one new water-soluble platinum complex with FIP and phen with a new formula of [Pt(phen)(FIP)](NO3)2 was prepared and specified. DFT data can be used to evaluate geometry parameters. Based on the ADMET prediction, this complex can be considered a drug-like agent. Cytotoxicity property was evaluated against some human cancerous MCF7, A549, and HCT116 cell lines. Accumulation of Pt complex, cisplatin, and oxaliplatin in each cancerous cell was determined, which is probably related to their lipophilicity and solubility properties. The binding mode of the complex to ct-DNA was investigated by fluorescence spectroscopy, circular dichroism, and molecular docking simulation. The viscosity of DNA by different concentrations of EB and Pt complex titration shows Pt complex interacts with DNA via groove binding like the spectroscopic binding result. In the MD study, DNA helix, RMSD, and RMSF analysis showed that DNA stability decreased and that the majority of residues left the initial state. DNA increased residual deviations and flexibility are linked to an increase in its gyratory radius, which is consistent with the findings of the experiments.

Green Synthesis and Bioactivity of Aliphatic N-Substituted Glycine Derivatives

Standard amino acids have an asymmetric α-carbon atom to which -COOH, -NH2, -H, and -R groups are bonded. Among them, glycine is the simplest (R = -H) with no asymmetric carbon, and other natural amino acids are C-substituted of glycine. Here, we have designed and made a green synthesis of some new N-substituted glycine derivatives with R-(NH)CH2-COOH formula, where R is flexible and hydrophobic with different chain lengths and benches of the type propyl, butyl, sec-butyl, tert-butyl, pentyl, isopentyl, tert-pentyl, hexyl, 2-aminoheptyl, and octyl. These glycine derivatives were characterized by recording their melting points and FT-IR, mass, 1H NMR, and 13C NMR spectra. DFT studies revealed that 2-aminoheptyl glycine had the highest electronegativity value and can thus act as a good bidentate ligand for the metal centers. ADME comparative results and bioavailability radars indicated that both octyl- and 2-aminoheptyl glycine had the most lipophilicity, making them good agents in cell passing. Furthermore, lipophilicity determination showed that octyl glycine was the best and propylgly was more soluble than others. Based on solubility, lipophilicity, and dipole moment values, propyl- and 2-aminoheptyl-glycine were considered for bio-macromolecular interaction studies. Thus, the interaction of these two agents with DNA and HSA was studied using absorption spectroscopy and circular dichroism techniques. Due to the presence of the R-amine group, they can interact with the DNA by H-binding and hydrophobicity, while electrostatic mode could not be ruled out. Meanwhile, molecular docking studies revealed that octyl- and 2-aminoheptyl glycine had the highest negative docking energy, which reflects their higher tendency to interact with DNA. The DNA binding affinity of two candidate AAs was determined by viscosity measurement and fluorescence emission recording, which confirms that groove binding occurs. Also, the toxicity of these synthesized amino acid derivates was tested against the human foreskin fibroblast (HFF) cell line. They showed IC50 values within the range of 127-344 μM after 48 h with the highest toxicity for 2-aminoheptyl glycine.

Molecular docking and spectroscopic study of bovine serum albumin interaction with new anticancer Pt complex with isopentyl dithiocarbamate ligand

Although cisplatin is useful in the treatment of cancer, it has a series of side effects that limit its use. Dithiocarbamates reduce the toxicity of platinum due to their structure and the presence of S, and N donating groups. In this article, the interaction of [Pt(bpy)(isopentyl.dtc)]NO3, where bpy is bipyridine and isopentyl.dtc is isopentyl-dithiocarbamate, with BSA, bovine serum albumin has been studied. The molecular binding method, including UV-Vis and fluorescence titration, was carried out in conditions including pH = 7.4 and temperatures of 27 and 37 °C. The negative values of enthalpy (ΔH°b) and entropy (ΔS°b) show that the driving forces of this interaction are hydrogen and van der Waals, and the negative value of the Gibbs free energy, ΔG°b indicates that the interaction proceeds spontaneously. The fluorescence results showed that the quenching mechanism is the static type and the Stern Volmer constant, KSV, was also obtained. The fluorescence titration method data displayed that the quenching mechanism is static. Binding constant (Kb), binding point (n), Hill coefficients, nH, Hill constant, KH, number of binding sites, g, BSA melting temperature, Tm, were also obtained. Finally, the molecular docking method result shows the binding constant, Ki and binding free energy for the platinum complex are -6.53 and 16.39 kcal mol-1, respectively, and also the proper position of binding on BSA can be considered the site I in the subdomain IIA.

High cancer selectivity and improving drug release from mesoporous silica nanoparticles in the presence of human serum albumin in cisplatin, carboplatin, oxaliplatin, and oxalipalladium treatment

In this project, drug release was examined based on the adsorption of cisplatin, carboplatin, oxaliplatin, and oxalipalladium on aminated mesoporous silica nanoparticles (N-HMSNs) and human serum albumin (HSA). These compounds were characterized by different techniques where three clinical Pt-drugs, cisplatin, carboplatin, oxaliplatin, plus oxalipalladium were loaded and investigated for release. Based on loading analysis, the loading ability of the mentioned metallodrug on N-HMSNs was dependent on the nature of the drug structure as well as hydrophobic or hydrophilic interactions. Different adsorption and release profiles were observed for all mentioned compounds via dialysis and ICP method analysis. Although the maximum to minimum loading occurred for oxalipalladium, cisplatin, and oxaliplatin to carboplatin, respectively, release from a surface with greater control belonged to carboplatin to cisplatin systems in the absence and presence of HSA to 48 hours due to weak interaction for carboplatin drug. The quick release of all mentioned compounds from the protein level at high doses of the drug during chemotherapy occurred very fast within the first 6 hours. In addition, the cytotoxic activity of both free drugs and drug-loaded@N-HMSNs samples on cancerous MCF-7, HCT116, A549, and normal HFF cell lines was evaluated by MTT assay. It was found that free metallodrugs exhibited more active cytotoxic behavior on both cancerous and normal cell lines than drug-loaded@N-HMSNs. Data demonstrated that the Cisplatin@N-HMSNs with SI=6.0 and 6.6 for MCF7 and HCT116 cell lines, respectively, and Oxaliplatin@N-HMSNs with SI=7.4 for HCT116 cell line can be good candidates as an anticancer drug with minimal side effects by protecting cytotoxic drugs as well as controlled release and high selectivity.

Spectroscopy and molecular dynamic study of the interaction of calf thymus DNA by anticancer Pt complex with butyl glycine ligand

Despite the past few decades since the discovery of anticancer drugs, there is still no definitive treatment for its treatment. Cisplatin is a chemotherapy medication used to treat some cancers. In this research, the DNA binding affinity of Pt complex with butyl glycine ligand was studied by various spectroscopy methods and simulation studies. Fluorescence and UV-Vis spectroscopic data showed groove binding in ct-DNA-[Pt(NH₃)₂(butylgly)]NO₃ complex formation by the spontaneous process. The results were also confirmed by small changes in CD spectra and thermal study (T_m), as well as the quenching emission of [Pt(NH₃)₂(butylgly)]NO₃ complex on DNA. Finally, thermodynamic and binding parameters displayed that hydrophobic forces are the main forces. Based on docking simulation, [Pt(NH₃)₂(butylgly)]NO₃ could bind to DNA and via minor groove binding on C-G center on DNA, formed a stable DNA complex.

In-vitro cytotoxicity and in-vivo antitumor activity of two platinum complexes with 1,3-dimethyl pentyl glycine ligand against breast cancer

Platinum (Pt) derivatives are good candidates for discovering new anti-tumor agents. The present research aims to explore the in-vivo and in-vitro anticancer activity of two platinum complexes with 1,3-dimethyl pentyl glycine ligand (DMPG), [Pt(bpy)(13DMPG)]NO₃ and [Pt(dach)(13DMPG)]NO₃, against breast cancer cells. The present study was conducted to investigate the cytotoxic potential of these compounds (2-400 μM) compared to standard drugs (cisplatin, oxaliplatin, and carboplatin) on SKBR3 cells using the methyl thiazol-tetrazolium (MTT) assay. Furthermore, the gene expression changes of Bak, Bim, Bcl-2, Caspase-3, and Caspase-9 were carried out by real-time polymerase chain reaction (PCR), and flow cytometric analysis was performed to confirm the cell apoptosis in the presence of the compounds. For more validation, in-vivo anticancer activities of both compounds were investigated against breast transplanted tumors in the BALB/c mice model. The cytotoxic studies by MTT assay revealed the anti-proliferative potential of both derivatives. [Pt(dach)(13DMPG)]NO₃ with an IC₅₀ value of 15 μM, exhibited higher cytotoxicity against SKBR3 cells as compared to [Pt(bpy)(13DMPG)]NO₃, oxaliplatin, and carboplatin. Based on the flow cytometry analysis, both derivatives demonstrated apoptotic effects. Also, real-time PCR analysis revealed an up-regulation of Bak, Bim, Bax, Caspases-3, and Caspase-9 genes and a significant reduction in Bcl-2 gene expression in treated cells with both compounds compared to the control group. In-vivo results validated in-vitro analysis and showed the anticancer activity of compounds against breast transplanted tumors in the BALB/c mice model. According to the results, [Pt(dach)(13DMPG)]NO₃ displayed a significant anticancer activity.

Transition Metal-Decorated B12N12-X (X = Au, Cu, Ni, Os, Pt, and Zn) Nanoclusters as Biosensors for Carboplatin

Theoretical studies on the adsorption, sensibility, and reactivity of a boron nitride nanocage decorated with Au, Cu, Ni, Os, Pt, and Zn metals as a biosensor material were carried out for the adsorption of carboplatin by applying the density functional theory computation at the B3LYP-GD3BJ/def2svp level of theory. All the optimized structures, as well as the calculations as regards the studied objective including electronic properties, geometry optimization parameters, adsorption energy studies, natural bond orbital analysis, topology studies, sensor mechanistic parameters, and thermodynamic properties (ΔG and ΔH), were investigated herein. As a result, the noticeable change in the energy gap of the studied surfaces when interacting with carboplatin accounted for the surfaces' reactivity, stability, conductivity, work function, and overall adsorption ability, implying that the studied decorated surfaces are good sensor materials for sensing carboplatin. Furthermore, the negative adsorption energies obtained for interacting surfaces decorated with Cu, Ni, Os, and Zn suggest that the surface has a superior ability to sense carboplatin as chemisorption was seen. Substantially, the geometric short adsorption bond length after adsorption, thermodynamically spontaneous reactions, and acceptable sensor mechanism results demonstrate that the investigated surfaces have strong sensing characteristics for sensing carboplatin.

Biological Activity of Two Anticancer Pt Complexes with a Cyclohexylglycine Ligand against a Colon Cancer Cell Line: Theoretical and Experimental Study

Because of their extraordinary ability to disrupt the natural structure of nucleic acids, metal complexes could be used in cancer therapy. In this study, cyclohexylglycine (HL) as a ligand and two new Pt complexes, [Pt(NH₃)₂(L)]NO₃ (1) and [Pt(bipy)(L)]NO₃ (2), were synthesized and characterized by elemental analysis, LC-MS, UV-vis spectrometry, FT-IR, ¹H NMR spectroscopy, ¹³C NMR spectroscopy, ¹⁹⁵Pt NMR spectroscopy, HPLC analysis, and single-crystal X-ray diffraction. Complex 2 crystallized in the orthorhombic Pbca space group, and density functional theory (DFT) was used to describe its structural parameters were described in detail. These complexes can be classified as oral medications and drug-like molecules based on a comparison of their absorption, distribution, metabolism, and excretion assessment. Quantum chemical descriptors (QCDs) were determined using DFT calculations to predict the tendency of DNA to approach these complexes. During the determination of the function of the metallodrug in DNA binding, the fluorescence data indicated that static quenching took place for all ligands and complexes with higher DNA binding affinity. CD and isothermal absorption studies indicate the presence of electrostatic and groove binding for the amine derivative and that DNA binds with the bipy moiety via groove binding. Furthermore, the interaction modes were determined using molecular docking to investigate the binding of these compounds with the target DNA molecule. According to docking investigations, binding energies of -5.7, -11.56, and -10.00 kcal/mol for HL and complexes 1 and 2, respectively, indicate partially electrostatic and groove binding. The anticancer activities of the Pt(II) complexes were tested against the HCT116 human colon cancer cell line, with IC₅₀ values of 35.51 and 51.33 μM for 1 and 2, respectively, after 72 h. These values show that the inhibitory effect of complex 1 was better than those of 2 and carboplatin (IC₅₀ = 51.94 μM).