Anticancer Activity and Mechanism of Action Evaluation of an Acylhydrazone Cu(II) Complex toward Breast Cancer Cells, Spheroids, and Mammospheres

Biodynamers: applications of dynamic covalent chemistry in single-chain polymer nanoparticles

Dynamic Covalent Chemistry (DCC) enables the development of responsive molecular systems through the integration of reversible bonds at the molecular level. These systems are thermodynamically stable and capable of undergoing various molecular assemblies and transformations, allowing them to adapt to changes in environmental conditions like temperature and pH. Introducing DCC into the field of polymer science has led to the design of Single-Chain Nanoparticles (SCNPs), which are formed by self-folding via intramolecular crosslinking mechanisms. Defined by their adaptability, SCNPs mimic biopolymers in size and functionality. Biodynamers, a subclass of SCNPs, are specifically designed for their stimuli-responsive and tunable, dynamic properties. Mimicking complex biological structures, their scope of application includes target-specific and pH-responsive drug delivery, enhanced cellular uptake and endosomal escape. In this manuscript, we discuss the integration of DCC for the design of SCNPs, focusing particularly on the characteristics of biodynamers and their biomedical and pharmaceutical applications. By underlining their potential, we highlight the factors driving the growing interest in SCNPs, providing an overview of recent developments and future perspectives in this research field.

Promising Dual Anticancer and Antimetastatic Action by a Cu(II) Complex Derived from Acylhydrazone on Human Osteosarcoma Models

Osteosarcoma cancers are becoming more common in children and young adults, and existing treatments have low efficacy and a very high mortality rate, making it pressing to search for new chemotherapies with high efficacy and high selectivity index. Copper complexes have shown promise in the treatment of osteosarcoma. Here, we report the synthesis, characterization, and anticancer activity of [Cu(N-N-Fur)(NO3)(H2O)] complex where N-N-Fur is (E)-N'-(2-hydroxy-3-methoxybenzylidene)furan-2-carbohydrazide. The [Cu(N-N-Fur)(NO3)(H2O)] complex was characterized via X-ray diffraction and electron spin resonance (ESR), displaying a copper center in a nearly squared pyramid environment with the nitrate ligand acting as a fifth ligand in the coordination sphere. We observed that [Cu(N-N-Fur)(NO3)(H2O)] binds to DNA in an intercalative manner. Anticancer activity on the MG-63 cell line was evaluated in osteosarcoma monolayer (IC50 2D: 1.1 ± 0.1 μM) and spheroids (IC50 3D: 16.3 ± 3.1 μM). Selectivity assays using nontumoral fibroblast (L929 cell line) showed that [Cu(N-N-Fur)(NO3)(H2O)] has selectivity index value of 2.3 compared to cis-diamminedichloroplatinum(II) (CDDP) (SI = 0.3). Additionally, flow cytometry studies demonstrated that [Cu(N-N-Fur)(NO3)(H2O)] inhibits cell proliferation and conveys cells to apoptosis. Cell viability studies of MG-63 spheroids (IC50 = 16.3 ± 3.1 μM) showed that its IC50 value is 4 times lower than for CDDP (IC50 = 65 ± 6 μM). Besides, we found that cell death events mainly occurred in the center region of the spheroids, indicating efficient transport to the microtumor. Lastly, the complex showed dose-dependent reductions in spheroid cell migration from 7.5 to 20 μM, indicating both anticancer and antimetastatic effects.

Assessment of Mononuclear/Dinuclear copper acylhydrazone complexes for lung cancer treatment

Non-platinum metal-based complexes have good potential for cancer treatment. Here, we designed and synthesized five hydrazone copper(II) complexes, [Cu2(HL)2Cl2] 1A, [Cu2(HL)2(NO3)H2O]·NO3 2A, [Cu2(HL)2Br2] 3A, [Cu(L)pyridine] 1B and [Cu(HL)(pyridine)Br] 3B, and evaluated their anti-lung cancer activities. MTT experiments revealed that these copper(II) complexes exhibit higher anticancer activity than cisplatin. Mechanism studies revealed that complex 3A induced G1 phase cell cycle arrest, and induced cell apoptosis via reactive oxygen species (ROS)-mediated mitochondrial dysfunction. Scratch wound healing assay was also performed, revealing that complex 3A have good anti-cell migration activity. Hemolysis assays showed good blood biocompatibility of complex 3A. Furthermore, complex 3A can significantly inhibit the proliferation of A549 3D tumor spheroid. An in vivo anticancer study showed that complex 3A could delays the growth of A549 tumor xenografts with lower systemic toxicity. These results highlight the great possibility of developing highly active copper complexes as anti-lung cancer agents.

New copper(II) and oxidovanadium(IV) complexes with a vitamin B6 Schiff base: mechanism of action and synergy studies on 2D and 3D human osteosarcoma cell models

We report the synthesis, characterization and anticancer activity of a new Schiff base (H2L) derived from the condensation of pyridoxamine with pyridoxal and its novel copper(II) and oxidovanadium(IV) complexes: [Cu(HL)Cl] (1), [Cu(LH2)(phen)]Cl2 (2), [Cu(LH2)(amphen)]Cl2 (3), [VIVO(HL)Cl] (4), and [VIVO(LH2)(phen)]Cl2 (5), where phen is 1,10-phenanthroline and amphen is its 5-amino derivative. All compounds were characterized by analytical and spectroscopic techniques, namely FTIR, UV-vis and EPR spectroscopy. Their stability in aqueous media was evaluated, revealing that the presence of the phen co-ligand significantly increases the stability. The ternary Cu(II) complexes (2 and 3) impaired cell viability of osteosarcoma cells (MG-63) (IC50 values of 3.6 ± 0.6 and 7 ± 1.9 μM for 2 and 3), while 1 and the VIVO complexes did not show relevant anticancer activity. Complexes 2 and 3 are also more active than cisplatin (CDDP). Synergistic studies between 2 and sorafenib showed significant synergism on MG-63 cells for the following combinations: 2 (2.0 μM) + sorafenib (10.0 μM) and 2 (2.5 μM) + sorafenib (12.5 μM), whilst the combination of 2 and CDDP did not show synergy. Complex 2 interacts with DNA, inducing significant genotoxic effects on MG-63 cells from 1.0 to 2.5 μM and it increases the ROS levels 880% over basal. Moreover, 2 induces apoptosis at 1.0 and 2.0 μM, while its combination with sorafenib induces apoptosis and necrosis. Finally, compound 2 reduces the cell viability of MG-63 spheroids showing an IC50 value 7-fold lower than that of CDDP (8.5 ± 0.4 μM vs. 65 ± 6 μM). The combination of 2 and sorafenib also showed synergism on spheroids, suggesting that the combination of these drugs improves the anticancer effect against bone cancer cells.

Copper(II) complexes of a furan-containing aroylhydrazonic ligand: syntheses, structural studies, solution chemistry and interaction with HSA

Copper(II) complexes have become a potential alternative to the use of platinum drugs in cancer therapy due to their multi-target mode of action. In this context, we report the syntheses of new mononuclear and dinuclear coordination compounds of this element, 1 and 2, derived from the ligand 5-methylsalicylaldehyde 2-furoyl hydrazone (H2L). All three compounds were structurally and spectroscopically characterized, both in the solid state and in solution. In 1, Cu is coordinated by three donor-atoms from the hydrazonic ligand and one chloride ion. H2L is deprotonated at the phenol oxygen. The dinuclear complex 2 is, on the other hand, a dimeric form of 1 in which the chloride ions of a pair of mononuclear units are lost and phenoxo bridges take their places, double-connecting the metal centres and resulting in a single species with the ligand fully deprotonated. The compounds were fairly stable in aqueous medium at room temperature. An experimental-theoretical combined approach demonstrated that all of them are able to bind human serum albumin (HSA), although at different sites and with diverse stoichiometries and affinities (as concluded by the calculated binding energies). In view of this, and due to the well-known antiproliferative activity of hydrazone-containing copper complexes, we consider the compounds presented in here promising, and believe that they deserve more profound studies regarding the assessment of their potential against tumour cell lines.

Cu(II)-acylhydrazone complex, a potent and selective antitumor agent against human osteosarcoma: Mechanism of action studies over in vitro and in vivo models

Osteosarcoma (OS) is a frequent bone cancer, affecting largely children and young adults. Cisplatin (CDDP) has been efficacious in the treatment of different cancer such us OS but the development of chemoresistance and important side effects leading to therapeutic failure. Novel therapies including copper compounds have shown to be potentially effective as anticancer drugs and one alternative to usually employed platinum compounds. The goal of this work is the evaluation of the in vitro and in vivo antitumoral activity and dilucidate the molecular target of a Cu(II) cationic complex containing a tridentate hydrazone ligand, CuHL for short, H2L=N'-'-(2-hydroxy-3-methoxybenzylidene)thiophene-2-carbohydrazide, against human OS MG-63 cells. Anticancer activity on MG-63 cell line was evaluated in OS monolayer and spheroids. CuHL significantly impaired cell viability in both models (IC50 2D: 2.1 ± 0.3 μM; 3D: 9.1 ± 1.0 μM) (p < 0.001). Additional cell studies demonstrated the copper compound inhibits cell proliferation and conveys cells to apoptosis, determined by flow cytometry. CuHL showed a great genotoxicity, evaluated by comet assay. Proteomic analysis by Orbitrap Mass Spectometry identified 27 differentially expressed proteins: 17 proteins were found overexpressed and 10 underexpressed in MG-63 cells after the CuHL treatment. The response to unfolded protein was the most affected biological process. In addition, in vivo antitumor effects of the compound were evaluated on human OS tumors xenografted in nude mice. CuHL treatment, at a dose of 2 mg/kg i.p., given three times/week for one month, significantly inhibited the progression of OS xenografts and was associated to a reduction in mitotic index and to an increment of tumor necrosis (p < 0.01). Administration of standard-of-care cytotoxic agent CDDP, following the same treatment schedule as CuHL, failed to impair OS growth and progression.

Finding New Molecular Targets of Two Copper(II)-Hydrazone Complexes on Triple-Negative Breast Cancer Cells Using Mass-Spectrometry-Based Quantitative Proteomics

Breast cancer is the most common cancer in women, with a high incidence estimated to reach 2.3 million by 2030. Triple-Negative Breast Cancer (TNBC) is the greatest invasive class of breast cancer with a poor prognosis, due to the side-effects exerted by the chemotherapy used and the low effectivity of novel treatments. In this sense, copper compounds have shown to be potentially effective as antitumor agents, attracting increasing interest as alternatives to the usually employed platinum-derived drugs. Therefore, the aim of this work is to identify differentially expressed proteins in MDA-MB-231 cells exposed to two copper(II)-hydrazone complexes using label-free quantitative proteomics and functional bioinformatics strategies to identify the molecular mechanisms through which these copper complexes exert their antitumoral effect in TNBC cells. Both copper complexes increased proteins involved in endoplasmic reticulum stress and unfolded protein response, as well as the downregulation of proteins related to DNA replication and repair. One of the most relevant anticancer mechanisms of action found for CuHL1 and CuHL2 was the down-regulation of gain-of-function-mutant p53. Moreover, we found a novel and interesting effect for a copper metallodrug, which was the down-regulation of proteins related to lipid synthesis and metabolism that could lead to a beneficial decrease in lipid levels.

Design, Synthesis, Characterization, and Evaluation of the Anti-HT-29 Colorectal Cell Line Activity of Novel 8-Oxyquinolinate-Platinum(II)-Loaded Nanostructured Lipid Carriers Targeted with Riboflavin

Colorectal cancer is occasionally called colon or rectal cancer, depending on where cancer begins to form, and is the second leading cause of cancer death among both men and women. The platinum-based [PtCl(8-O-quinolinate)(dmso)] (8-QO-Pt) compound has demonstrated encouraging anticancer activity. Three different systems of 8-QO-Pt-encapsulated nanostructured lipid carriers (NLCs) with riboflavin (RFV) were investigated. NLCs of myristyl myristate were synthesized by ultrasonication in the presence of RFV. RFV-decorated nanoparticles displayed a spherical shape and a narrow size dispersion in the range of 144-175 nm mean particle diameter. The 8-QO-Pt-loaded formulations of NLC/RFV with more than 70% encapsulation efficiency showed sustained in vitro release for 24 h. Cytotoxicity, cell uptake, and apoptosis were evaluated in the HT-29 human colorectal adenocarcinoma cell line. The results revealed that 8-QO-Pt-loaded formulations of NLC/RFV showed higher cytotoxicity than the free 8-QO-Pt compound at 5.0 µM. All three systems exhibited different levels of cellular internalization. Moreover, the hemotoxicity assay showed the safety profile of the formulations (less than 3.7%). Taken together, RFV-targeted NLC systems for drug delivery have been investigated for the first time in our study and the results are promising for the future of chemotherapy in colon cancer treatment.

Cellular and molecular basis of therapeutic approaches to breast cancer

In recent decades, there has been a significant amount of research into breast cancer, with some important breakthroughs in the treatment of both primary and metastatic breast cancers. It's a well-known fact that treating breast cancer is still a challenging endeavour even though physicians have a fantastic toolset of the latest treatment options at their disposal. Due to limitations of current clinical treatment options, traditional chemotherapeutic drugs, and surgical options are still required to address this condition. In recent years, there have been several developments resulting in a wide range of treatment options. This review article discusses the cellular and molecular foundation of chemotherapeutic drugs, endocrine system-based treatments, biological therapies, gene therapy, and innovative techniques for treating breast cancer.

Anticancer and Antioxidant Activity of Water-Soluble Polysaccharides from Ganoderma aff. australe against Human Osteosarcoma Cells

Wild mushrooms have gained great importance for being a source of biologically active compounds. In this work, we evaluate the anticancer and antioxidant activity of a water-soluble crude polysaccharide extract isolated from the fruiting bodies of the Ganoderma aff. australe (GACP). This mushroom was collected in San Mateo (Boyacá, Colombia) and identified based on macroscopic and microscopic characterization. GACP was characterized by UV-Vis spectroscopy, Fourier-transform infrared spectroscopy, high-performance liquid chromatography-diode array detector, and nuclear magnetic resonance. The antiradical and antioxidant activity were evaluated by different methods and its anticancer activity was verified in the osteosarcoma MG-63 human cell line. Chemical and spectroscopic analysis indicated that GACP consisted of β-D-Glcp-(1→, →3)-β-D-Glcp-(1→ and α-D-Glcp-(1→ residues. The results of the biological activity showed that GACP exhibited high antioxidant activity in the different methods and models studied. Moreover, the results showed that GACP impaired cell viability (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay) and cell proliferation (clonogenic assay) in a dose-response manner on MG-63 cells. The findings of this work promote the use of mushroom-derived compounds as anticancer and antioxidant agents for potential use in the pharmaceutical and food industries.