Novel Antitumor Platinum(II) Conjugates Containing the Nonsteroidal Anti-inflammatory Agent Diclofenac: Synthesis and Dual Mechanisms of Antiproliferative Effects

N-Indolyl diiron vinyliminium complexes exhibit antiproliferative effects in cancer cells associated with disruption of mitochondrial homeostasis, ROS scavenging, and antioxidant activity

The indole scaffold has been established as a key organic moiety for developing new drugs; on the other hand, a range of diiron bis-cyclopentadienyl complexes have recently emerged for their promising anticancer potential. Here, we report the synthesis of novel diiron complexes with an indole-functionalized vinyliminium ligand (2-5) and an indole-lacking analogue for comparative purposes (6), which were characterized by analytical and spectroscopic techniques. Complexes 2-6 are substantially stable in DMSO‑d6 and DMEM-d solutions at 37 °C (8% average degradation after 48 h) and display a balanced hydrophilic/lipophilic behaviour (LogPow values in the range -0.32 to 0.47), associated with appreciable water solubility. The complexes display selective antiproliferative potency towards several cancer cells in monolayer cultures, mainly in the low micromolar range, with reduced toxicity towards noncancerous epithelial cells. Thus, the cytotoxicity of the complexes is comparable to or better than clinically used metallopharmaceutical cisplatin. Comparing the antiproliferative activity obtained for complexes containing different ligands, we confirmed the importance of the indolyl group in the mechanism of antiproliferative activity of these complexes. Cell-based mechanistic studies suggest that the investigated diiron vinyliminium complexes (DVCs) show cytostatic rather than cytotoxic effects and subsequently induce a population of cells to undergo apoptosis. Furthermore, the molecular mechanism of action involves interactions with mitochondrial DNA and proteins, the reactive oxygen species (ROS)-scavenging properties and antioxidant activity of these complexes in cancer cells. This study highlights the importance of DVCs to their cancer cell activity and reinforces their prospective therapeutic potential as anticancer agents.

Regulating tumor glycometabolism and the immune microenvironment by inhibiting lactate dehydrogenase with platinum(iv) complexes

Lactate dehydrogenase (LDH) is a key enzyme involved in the process of glycolysis, assisting cancer cells to take in glucose and generate lactate, as well as to suppress and evade the immune system by altering the tumor microenvironment (TME). Platinum(iv) complexes MDP and DDP were prepared by modifying cisplatin with diclofenac at the axial position(s). These complexes exhibited potent antiproliferative activity against a panel of human cancer cell lines. In particular, DDP downregulated the expression of LDHA, LDHB, and MCTs to inhibit the production and influx/efflux of lactate in cancer cells, impeding both glycolysis and glucose oxidation. MDP and DDP also reduced the expression of HIF-1α, ARG1 and VEGF, thereby disrupting the formation of tumor vasculature. Furthermore, they promoted the repolarization of macrophages from the tumor-supportive M2 phenotype to the tumor-suppressive M1 phenotype in the TME, thus enhancing the antitumor immune response. The antitumor mechanism involves reprogramming the energy metabolism of tumor cells and relieving the immunosuppressive TME.

Platinum(IV) Derivatives of [Pt(1S,2S-diaminocyclohexane)(5,6-dimethyl-1,10-phenanthroline)] with Diclofenac Ligands in the Axial Positions: A New Class of Potent Multi-action Agents Exhibiting Selectivity to Cancer Cells

The platinum(II) complex [Pt(1S,2S-diaminocyclohexane)(5,6-dimethyl-1,10-phenanthroline)]²⁺ (Pt^II56MeSS, 1) exhibits high potency across numerous cancer cell lines acting by a multimodal mechanism. However, 1 also displays side toxicity and in vivo activity; all details of its mechanism of action are not entirely clear. Here, we describe the synthesis and biological properties of new platinum(IV) prodrugs that combine 1 with one or two axially coordinated molecules of diclofenac (DCF), a non-steroidal anti-inflammatory cancer-selective drug. The results suggest that these Pt(IV) complexes exhibit mechanisms of action typical for Pt(II) complex 1 and DCF, simultaneously. The presence of DCF ligand(s) in the Pt(IV) complexes promotes the antiproliferative activity and selectivity of 1 by inhibiting lactate transporters, resulting in blockage of the glycolytic process and impairment of mitochondrial potential. Additionally, the investigated Pt(IV) complexes selectively induce cell death in cancer cells, and the Pt(IV) complexes containing DCF ligands induce hallmarks of immunogenic cell death in cancer cells.

In vitro and In vivo Studies of Potential Anticancer Agents of Platinum(II) Complexes of Dicyclopentadiene and Dithiocarbamates

Three platinum(II) complexes of dicyclopentadiene (DCP) and dithiocarbamates (DTC), namely, [Pt(η4-DCP)(Me2DTC)]PF6 (1), [Pt(η4-DCP)(Et2DTC)]PF6 (2) and [Pt(η4-DCP)(Bz2DTC)]PF6 (3) [Me2DTC = dimethyldithiocarbamate, Et2DTC = diethyldithiocarbamate, and Bz2DTC = dibenzyldithiocarbamate] were prepared and characterized by elemental analysis, IR, 1H and 13C NMR spectroscopy. The spectroscopic data indicated the coordination of both DCP and dithiocarbamate ligands to platinum(II). The solution chemisty of complex 1 revealed that the complexes are stable in both DMSO and 1:1 mixture of DMSO: H2O. In vitro cytotoxicity of the complexes relative to cisplatin was tested using MTT assay, against CHL-1 (human melanoma cancer cells), MDA-MB-231 (breast cancer cells), A549 (lung cancer cells), and B16 (murine melanoma cancer cells). The antiproliferative effect of all three prepared complexes was found to be significantly higher than cisplatin. Furthermore, flow cytometric analysis of complex 1 showed that the complex induced apoptosis, oxidative stress, mitochondrial potential depolarization and cell cycle arrest in a concentration-dependent pattern in the CHL-1 cells. Confirmation of apoptosis via gene expression analysis demonstrated down-regulation of anti-apoptotic genes and up-regulation of pro-apoptotic genes in the CHL-1 cells. Wound healing assays also lent support to the strong cytotoxicity of the complexes. In vivo studies showed a significant reduction of tumor volume at the end of the experiment. In addition, the drug did not change the weight of the mice. In conclusion, complex 1 inhibited cell proliferation in vitro and reduced tumor growth in vivo.

Pro-Inflammatory Signalling PRRopels Cisplatin-Induced Toxicity

Cisplatin is a platinum-based chemotherapeutic that has long since been effective against a variety of solid-cancers, substantially improving the five-year survival rates for cancer patients. Its use has also historically been limited by its adverse drug reactions, or cisplatin-induced toxicities (CITs). Of these reactions, cisplatin-induced nephrotoxicity (CIN), cisplatin-induced peripheral neuropathy (CIPN), and cisplatin-induced ototoxicity (CIO) are the three most common of several CITs recognised thus far. While the anti-cancer activity of cisplatin is well understood, the mechanisms driving its toxicities have only begun to be defined. Most of the literature pertains to damage caused by oxidative stress that occurs downstream of cisplatin treatment, but recent evidence suggests that the instigator of CIT development is inflammation. Cisplatin has been shown to induce pro-inflammatory signalling in CIN, CIPN, and CIO, all of which are associated with persisting markers of inflammation, particularly from the innate immune system. This review covered the hallmarks of inflammation common and distinct between different CITs, the role of innate immune components in development of CITs, as well as current treatments targeting pro-inflammatory signalling pathways to conserve the use of cisplatin in chemotherapy and improve long-term health outcomes of cancer patients.

Silver(I) complexes containing diclofenac and niflumic acid induce apoptosis in human-derived cancer cell lines

We investigated the anti-cancer activity of [Ag(μ-dicl)]_n 1 and [AgH(nif)₂] 2 complexes against human cancer cell lines (MCF-7, HT-29, and HepG2) and mouse fibroblast (3T3-L1) cell line. Anti-proliferative activity was monitored by XTT cell viability and LDH leakage assays. Cell death mode was evaluated by multi-caspase activity, annexin V cytofluorimetric, MMP, cell cycle arrest, and ROS generation assays. Antioxidant capacity was evaluated on SOD, GPx, GR, and CAT enzymes. The XTT and LDH assay results showed that both complexes exhibited strong cytotoxicity against the tested cancer cell lines. The apoptotic mechanisms of the complexes were demonstrated by loss of MMP and increase in phosphatidylserine translocation, sub-G1 phase, and multi-caspase activity. Besides, both complexes induced the oxidative stress in MCF-7 cells by decreasing the activity of GPx, GR, and CAT enzymes. In conclusion, both Ag(I) complexes, especially 1, warrant for further in vivo evaluation as a new alternative in cancer treatment.HighlightsAg(I) complexes inhibited cell proliferation and induced LDH leakage in human cancer cell lines.Ag(I) complexes induced apoptosis through MMP disruption and ROS generation.Ag(I) complexes mimicked the multi-caspase activity.Ag(I) complexes increased the accumulation of sub-G1 phase.Ag(I) complexes inhibited the activity of antioxidant system enzymes.

Systematic evaluation of the antitumor activity of three ruthenium polypyridyl complexes

Ruthenium-containing complexes have emerged as good alternative to the currently used platinum-containing drugs for malignant tumor therapy. In this work, cytotoxic effects of recently synthesized ruthenium polypyridyl complexes [Ru(bpy)₂(CFPIP)](ClO₄)₂ (bpy = 2,2'-bipyridine, CFPIP = (E)-2-(4-fluorostyryl)-1H-imidazo[4,5-f][1,10]phenanthroline, Ru(II)-1), [Ru(phen)₂(CFPIP)](ClO₄)₂ (phen = 1,10-phenanthroline, Ru(II)-2) and [Ru(dmb)₂(CFPIP)](ClO₄)₂ (dmb = 4,4'-dimethyl-2,2'-bipyridine, Ru(II)-3) toward different tumor cells were investigated in vitro and compared with cisplatin, the most widely used chemotherapeutic drug against hepatocellular carcinoma (HepG-2). The results demonstrate that target complexes show excellent cytotoxicity against HepG-2 cells with low IC₅₀ value of 21.4 ± 1.5, 18.0 ± 2.1 and 22.3 ± 1.7 μM, respectively. It was important noting that target Ru(II) complexes exhibited better antitumor activity than cisplatin (IC50 = 28.5 ± 2.4 μM) against HepG-2 cells, and has no obvious toxicity to normal cell LO2. DNA binding results suggest that Ru(II)-1, Ru(II)-2 and Ru(II)-3 interact with CT DNA (calf thymus DNA) through intercalative mode. Complexes exerted its antitumor activity through increasing anti-migration and inducing cell cycle arrest at the S phase. In addition, the apoptosis was tested by AO (acridine orange)/EB (ethidium bromide) staining and flow cytometry. Mitochondrial membrane potential (MMP), reactive oxygen species (ROS), and colocalization tests were also evaluated by ImageXpress Micro XLS system. Overall, the results show that the ruthenium polypyridyl complexes induce apoptosis in HepG-2 cells through ROS-mediated mitochondria dysfunction pathway.

Synthesis, Characterization, and Anticancer Activity of Benzothiazole Aniline Derivatives and Their Platinum (II) Complexes as New Chemotherapy Agents

We describe the synthesis, characterization, molecular modeling, and in vitro anticancer activity of three benzothiazole aniline (BTA) ligands and their corresponding platinum (II) complexes. We designed the compounds based on the selective antitumor properties of BTA, along with three types of metallic centers, aiming to take advantage of the distinctive and synergistic activity of the complexes to develop anticancer agents. The compounds were characterized using nuclear magnetic resonance spectrometry, Fourier transform infrared spectroscopy, mass spectrometry, elemental analysis, and tested for antiproliferative activity against multiple normal and cancerous cell lines. L1, L2, and L1Pt had better cytotoxicity in the liver, breast, lung, prostate, kidney, and brain cells than clinically used cisplatin. Especially, L1 and L1Pt demonstrated selective inhibitory activities against liver cancer cells. Therefore, these compounds can be a promising alternative to the present chemotherapy drugs.

Albumin-encapsulated Nanoparticles of Naproxen Platinum(IV) Complexes with Inflammation Inhibitory Competence Displaying Effective Antitumor Activities in vitro and in vivo

BACKGROUND

Platinum(IV) complexes with inflammation inhibitory properties are much favored in improving antitumor activities. Nanodrug-delivery system as a preferable measure for antitumor therapy are widely explored in platinum(IV) drug delivery.

PURPOSE

The aim for this study was to develop novel bovine serum albumin (BSA) nanoparticles (NPs) based on naproxen platinum(IV) complexes to display a synergistic antitumor mechanism targeting cyclooxygenase-2 (COX-2), metalloproteinase-9 (MMP-9) and inducible nitric oxide synthase (iNOS).

METHODS

Herein, we reported the preparation of two BSA NPs of naproxen platinum(IV) complexes, and their antitumor activities were investigated in vitro and in vivo.

RESULTS

Both NPs possessed relatively uniform size and good stability for 30 days in aqueous solution. They exhibited prominent antitumor activities in vitro, and showed great potential in reversing drug resistance. Furthermore, these two NPs played superior tumor growth suppression in vivo in contrast to the free compounds, which were comparable to that of cisplatin and oxaliplatin, but induced lower toxic influences than platinum(II) drugs especially to spleen and liver. Moreover, the naproxen platinum(IV) NPs could decrease tumor inflammation targeting COX-2, MMP-9 and iNOs, and decreasing NO production, which would be in favor of enhancing the antitumor competence, and reducing toxicity.

CONCLUSION

Taken together, BSA NPs of naproxen platinum(IV) complexes demonstrated a powerful antitumor efficacy in vitro and in vivo. The platinum(IV) NPs with inflammation inhibitory competence targeting multiple enzymes reported in this work afford a new strategy for the development of antitumor therapy to overcome drawbacks of clinical platinum(II) drugs.

Recent Progresses in Conjugation with Bioactive Ligands to Improve the Anticancer Activity of Platinum Compounds

Platinum (Pt) drugs, including cisplatin, are widely used for the treatment of solid tumors. Despite the clinical success, side effects and occurrence of resistance represent major limitations to the use of clinically available Pt drugs. To overcome these problems, a variety of derivatives have been designed and synthetized. Here, we summarize the recent progress in the development of Pt(II) and Pt(IV) complexes with bioactive ligands. The development of Pt(II) and Pt(IV) complexes with targeting molecules, clinically available agents, and other bioactive molecules is an active field of research. Even if none of the reported Pt derivatives has been yet approved for clinical use, many of these compounds exhibit promising anticancer activities with an improved pharmacological profile. Thus, planning hybrid compounds can be considered as a promising approach to improve the available Pt-based anticancer agents and to obtain new molecular tools to deepen the knowledge of cancer progression and drug resistance mechanisms.

A carrier-free anti-inflammatory platinum (II) self-delivered nanoprodrug for enhanced breast cancer therapy

Cisplatin is one of the most used first-line anticancer drugs for various solid tumor therapies. However, cisplatin-based chemotherapy can induce tumor cells to secrete excessive prostaglandin E2 (PGE2) catalyzed by cyclooxygenase-2 (COX-2), which, in turn, counteracts its chemotherapeutic effect and further accelerates tumor metastasis. Here, we report a carrier-free self-delivered nanoprodrug based on platinum (II) coordination bonding coupled with tolfenamic acid (Tolf) (named Tolfplatin). Tolfplatin can spontaneously assemble into uniformly sized nanoparticles (NPs) with a high drug-loading capacity. Compared with cisplatin, Tolfplatin NPs can facilitate cellular uptake, significantly decrease PGE2 secretion by COX-2 inhibition, which further downregulate tumorous anti-apoptotic and metastasis-associated proteins, thereby efficiently inducing apoptotic cell death and significantly inhibit tumor metastasis in vitro and in vivo. Therefore, as the carrier-free nanoprodrug, Tolfplatin NPs are promising anti-tumoral agents to inhibit tumor proliferation and metastasis by enriching the function and promoting the anti-tumor activity of cisplatin.

Cis,cis,trans-[PtIVCl2(NH3)2(perillato)2], a dual-action prodrug with excellent cytotoxic and antimetastatic activity

Two Pt(iv) conjugates containing one or two molecules of perillic acid (4-isopropenylcyclohexene-1-carboxylic acid), an active metabolite of limonene, were synthesized both with traditional and microwave-assisted methods and characterized. Their antiproliferative activity was tested on a panel of human tumor cell lines. In particular, cis,cis,trans-[Pt^IVCl₂(NH₃)₂(perillato)₂] exhibited excellent antiproliferative and antimetastatic activity on A-549 lung tumor cells at nanomolar concentrations. A number of in vitro biological tests were performed to decipher some aspects of its mechanism of action, including transwell migration and invasion as well as wound healing assay.

Platinum(IV)-Estramustine Multiaction Prodrugs Are Effective Antiproliferative Agents against Prostate Cancer Cells

Herein, we describe the synthesis, characterization, and biological properties of Pt(IV) derivatives of cisplatin with estramustine at the first axial position, which is known to disrupt the microtubule assembly and act as an androgen antagonist, and varying the second axial position using an innocent ligand (acetate or hydroxyl) to prepare dual-action and triple-action prodrugs with known inhibitors of histone deacetylase, cyclooxygenase, and pyruvate dehydrogenase kinase. We demonstrate superior antiproliferative activity at submicromolar concentrations of the prodrugs against a panel of cancer cell lines, particularly against prostate cancer cell lines. The results obtained in this study exemplify the complex mode of action of "multiaction" Pt(IV) prodrugs. Interestingly, changing the second axial ligand in the Pt-estramustine complex has a significant effect on the mode of action, suggesting that all three components of the Pt(IV) prodrugs (platinum moiety and axial ligands) contribute to the killing of cells and not just one dominant component.

Oxaliplatin and [Pt(R,R-DACH)(panobinostat-2H)] show nanomolar cytotoxicity towards diffuse intrinsic pontine glioma (DIPG)

We report the synthesis of two novel platinum(ii) complexes which incorporate histone deacetylase (HDAC) inhibitors: [Pt^II(R,R-DACH)(Sub_-H)] (1), [Pt^II(R,R-DACH)(panobinostat_-2H)] (2), where SubH = suberoyl-bis-hydroxamic acid; DACH = (1R,2R)-(-)-1,2-diaminocyclohexane and panobinostat = (E)-N-hydroxy-3-[4-[[2-(2-methyl-1H-indol-3-yl)ethylamino]methyl]phenyl]prop-2-enamide. Complexes 1 and 2 were characterised by ¹H, ¹³C, ¹⁹⁵Pt NMR spectroscopy and ESI-MS. Whilst oxaliplatin demonstrated considerable cytotoxicity in two patient-derived low-passage paediatric glioma DIPG cell lines (IC₅₀ values of 0.333 μM in SU-DIPG-IV, and 0.135 μM in SU-DIPG-XXI), complex 2 showed even greater cytotoxicities, with IC₅₀ values of 0.021 μM (SU-DIPG-IV), 0.067 μM (BIOMEDE 194) and 0.009 μM (SU-DIPG-XXI). Complex 2 also demonstrated superior aqueous solubility in comparison to panobinostat. Complex 2 released free intact panobinostat under HPLC conditions, as determined by ESI-MS. Incubation of solutions of oxaliplatin (H₂O) and panobinostat (DMF) resulted in instantaneous reactivity and precipitation of a panobinostat derivative which was not a platinum complex; the same reactivity was not observed between carboplatin and panobinostat.

Recent advances in platinum-based chemotherapeutics that exhibit inhibitory and targeted mechanisms of action

Current platinum-based drugs used in chemotherapy, like cisplatin and its derivatives, are greatly limited due to side-effects and drug resistance. This has inspired the search for novel platinum-based drugs that deviate from the conventional mechanism of action seen with current chemotherapeutics. This review highlights recent advances in platinum(II) and platinum(IV)-based complexes that have been developed within the past six years. The platinum compounds explored within this review are those that display a more targeted approach by incorporating ligands that act on selected cellular targets within cancer cells. This includes mitochondria, overexpressed receptors or proteins and enzymes that contribute to cancer cell proliferation. These types of platinum compounds have shown significant improvements in anticancer activity and as such, this review highlights the importance of pursuing these new designed platinum drugs for cancer therapy, with the potential of undergoing clinical trials.

Discovery of selective, antimetastatic and anti-cancer stem cell metallohelices via post-assembly modification

Helicates and related metallofoldamers, synthesised by dynamic self-assembly, represent an area of chemical space inaccessible by traditional organic synthesis, and yet with potential for discovery of new classes of drug. Here we report that water-soluble, optically pure Fe(ii)- and even Zn(ii)-based triplex metallohelices are an excellent platform for post-assembly click reactions. By these means, the in vitro anticancer activity and most importantly the selectivity of a triplex metallohelix Fe(ii) system are dramatically improved. For one compound, a remarkable array of mechanistic and pharmacological behaviours is discovered: inhibition of Na+/K+ ATPase with potency comparable to the drug ouabain, antimetastatic properties (including inhibition of cell migration, re-adhesion and invasion), cancer stem cell targeting, and finally colonosphere inhibition competitive with the drug salinomycin.

An Anticancer PtIV Prodrug That Acts by Mechanisms Involving DNA Damage and Different Epigenetic Effects

Dual- or multi-action Pt^IV prodrugs represent a new generation of platinum anticancer drugs. The important property of these Pt^IV prodrugs is that their antitumor action combines several different mechanisms owing to the presence of biologically active axial ligands. This work describes the synthesis and some biological properties of a "triple-action" prodrug that releases in cancer cells cisplatin and two different epigenetically acting moieties, octanoate and phenylbutyrate. It is demonstrated, with the aid of modern methods of molecular and cellular biology and pharmacology, that the presence of three different functionalities in a single molecule of the Pt^IV prodrug results in a selective and high potency in tumor cells including those resistant to cisplatin [the IC₅₀ values in the screened malignant cell lines ranged from as low as 9 nm (HCT-116) to 74 nm (MDA-MB-231)]. It is also demonstrated that cellular activation of the Pt^IV prodrug results in covalent modification of DNA through the release of the platinum moiety accompanied by inhibition of the activity of histone deacetylases caused by phenylbutyrate and by global hypermethylation of DNA by octanoate. Thus, the Pt^IV prodrug introduced in this study acts as a true "multi-action" prodrug, which is over two orders of magnitude more active than clinically used cisplatin, in both 2D monolayer culture and 3D spheroid cancer cells.

Half-sandwich Os(ii) and Ru(ii) bathophenanthroline complexes: anticancer drug candidates with unusual potency and a cellular activity profile in highly invasive triple-negative breast cancer cells

There is an urgent need to discover new, selective compounds to add to the limited arsenal of chemotherapeutics displaying selective toxicity for aggressive triple-negative breast cancer (TNBC) cells. The effect of two, recently developed metal-based half-sandwich complexes [Os(η6-pcym)(bphen)(dca)]PF6 (Os-dca) and [Ru(η6-pcym)(bphen)(dca)]PF6 (Ru-dca) [pcym = 1-methyl-4-(propan-2-yl)benzene (p-cymene); bphen = 4,7-diphenyl-1,10-phenanthroline (bathophenanthroline); dca = dichloroacetate] on triple-negative breast cancer cells MDA-MB-231 is reported. The complexes display selective toxicity in several tumor cells (at submicromolar concentrations), and a prominent effect is observed against highly progressive triple negative breast cancer MDA-MB-231 cells for Os-dca. The lower potency of Ru-dca in comparison with Os-dca is apparently connected with a relatively quick release of the dca ligand due to the hydrolysis of Ru-dca before this complex enters the cells. Remarkably, both Os-dca and Ru-dca reduce successfully metastasis-related properties of the triple-negative breast cancer cells such as migration, invasion, and re-adhesion. The anti-metastatic effects of Os-dca and Ru-dca are associated with their ability to suppress matrix metalloproteinase activity and/or production and reduce the expression of aquaporins. Further detailed mechanistic studies reveal that Os-dca reverses Warburg's effect and oncosis seems to be a prominent mode of cell death that predominates over apoptosis. As such, Os-dca can efficiently overcome the resistance of cancer cells to clinically-used apoptotic inducers cisplatin and carboplatin. The cytostatic and anti-metastatic properties of Os-dca in MDA-MB-231 provide a strong impetus for the development of new metal-based compounds to target hardly treatable human TNBC cells and displaying different modes of action compared to the antitumor metallodrugs in clinical use.

A Review of Chronic Musculoskeletal Pain: Central and Peripheral Effects of Diclofenac

Diclofenac is widely used to manage chronic inflammatory and degenerative joint diseases such as osteoarthritis (OA), rheumatoid arthritis (RA), ankylosing spondylitis, and extra-articular rheumatism. Its various mechanisms of action make it particularly effective in treating nociceptive pain, but it is also an alternative for treating spinal and chronic central pain. Osteoarthritis and rheumatoid arthritis are the most frequently encountered arthritic conditions in adults. The management of nociceptive pain requires a sequential hierarchical approach, with the initial NSAID treatment being characterized by the replacement of one drug with another, or complete discontinuation usually because of insufficient pain control. OA- and RA-related pain is complex and multifactorial, and due to physiological interactions between the signaling of the central and peripheral nervous systems. The mechanisms of action of diclofenac make it particularly effective in treating both nociceptive pain and chronic central pain. This review underlines the mechanisms of diclofenac involved in chronic and acute joint pain, the most relevant adverse events.

Hydrogen-Bonded Organic⁻Inorganic Hybrid Based on Hexachloroplatinate and Nitrogen Heterocyclic Cations: Their Synthesis, Characterization, Crystal Structures, and Antitumor Activities In Vitro

Three new crystal structures containing [PtCl₆]²⁻, pyridinium and benzimidazole groups have been prepared: [PtCl₆]·(H-bzm)₂·2(H₂O) (1), [PtCl₆]·(H-bipy)₂·2(H₂O) (2), [PtCl₆]·(H-dimethyl-bipy)₂·2(H₂O) (3) [H-bzm: benzimidazole cation, H-bipy: 2,2′-bipyridine cation, H-dimethyl-bipy: 4,4′-bimethyl-2,2′-bipyridine cation]. All compounds have been fully characterized by elemental analyses, single-crystal X-ray analyses, IR spectra, TG analyses, and fluorescence studies. Single-crystal X-ray diffraction analysis suggests that the primary synthon contains ⁺N–H···Cl⁻, including ionic bonding and hydrogen bonding interactions. The dimensions are enhanced further by secondary O–H ∙∙Cl and N–H ∙∙O hydrogen bonding interactions between donor and acceptor atoms located at the periphery of these synthons. Moreover, coulombic attractions between the ions play an important role in reinforcing the structures of these complexes. In addition, antitumor activity against human lung adenocarcinoma cell line (A549) and human nasopharyngeal carcinoma cell line (CNE-2) was performed. These complexes all showed inhibition to the two cell lines, while complex 3 exhibited higher efficiency than complexes 1–2.

Ruthenium(ii) arene NSAID complexes: inhibition of cyclooxygenase and antiproliferative activity against cancer cell lines

Ru(ii)–arene complexes with NSAIDs as co-ligands show marked antiproliferative activity against cancer cell lines along with cyclooxygenase inhibition properties.

Ruthenium–arene complexes with NSAIDs: synthesis, characterization and bioactivity

Two non-steroidal antiinflammatory drugs indomethacin and mefenamic acid were coordinated to Ru(ii)–arenes to afford four new complexes.

Photoactive platinum(II) complexes of nonsteroidal anti-inflammatory drug naproxen: Interaction with biological targets, antioxidant activity and cytotoxicity

The effect on the therapeutic efficacy of Pt(II) complexes on combining non-steroidal anti-inflammatory drugs (NSAIDs) is an attractive strategy to circumvent chronic inflammation mediated by cancer and metastasis. Two square-planar platinum(II) complexes: [Pt(dach)(nap)Cl] (1) and [Pt(dach)(nap)₂] (2), where dach = (1R,2R)-dichloro(cyclohexane-1,2-diamine) and NSAID drug naproxen (nap), have been designed for studying their biological activity. The naproxen bound to the Pt(II) centre get released upon photoirradiation with low-power UV-A light as confirmed by the significant enhancement in emission intensities of the complexes. The compounds were evaluated for their photophysical properties, photostability, reactivity with 5'-guanosine monophophosphate (5'-GMP), interactions with CT-DNA and BSA, antioxidant activity and reactive oxygen species mediated photo-induced DNA damage properties. ESI-MS studies demonstrated the formation of bis-adduct with 5'-GMP and the formation of Pt^II-DNA crosslinks by gel electrophoretic mobility shift assay and ITC studies. The interaction of the complexes 1 and 2 with the CT-DNA exhibits potential binding affinity (K_b ∼ 10⁴ M^-1, K_app∼ 10⁵ M^-1), implying intercalation to CT-DNA through planar naphthyl ring of the complexes. Both the complexes also exhibit strong binding affinity towards BSA (K_BSA∼ 10⁵ M^-1). The complexes exhibit efficient DNA damage activity on irradiation at 365 nm via formation of singlet oxygen (¹O₂) and hydroxyl radical (^•OH) under physiological conditions. Both the complexes were cytotoxic in dark and exhibit significant enhancement of cytotoxicity upon photo-exposure against HeLa and HepG2 cancer cells giving IC₅₀ values ranging from 8 to 12 μM for 1 and 2. The cellular internalization data showed cytosolic and nuclear localization of the complexes in the HeLa cells.

Research progress in modern structure of platinum complexes

Since the antitumor activity of cisplatin was discovered in 1967 by Rosenberg, platinum-based anticancer drugs have played an important role in chemotherapy in clinic. Nevertheless, platinum anticancer drugs also have caused severe side effects and cross drug resistance which limited their applications. Therefore, a significant amount of efforts have been devoted to developing new platinum-based anticancer agents with equal or higher antitumor activity but lower toxicity. Until now, a large number of platinum-based complexes have been prepared and extensively investigated in vitro and in vivo. Among them, some platinum-based complexes revealing excellent anticancer activity showed the potential to be developed as novel type of anticancer agents. In this account, we present such platinum-based anticancer complexes which owning various types of ligands, such as, amine carrier ligands, leaving groups, reactive molecule, steric hindrance groups, non-covalently binding platinum (II) complexes, Platinum(IV) complexes and polynuclear platinum complexes. Overall, platinum-based anticancer complexes reported recently years upon modern structure are emphasized.

A general strategy to add diversity to ruthenium arene complexes with bioactive organic compounds via a coordinated (4-hydroxyphenyl)diphenylphosphine ligand

Esterification of (4-hydroxyphenyl)diphenylphosphine, coordinated to the [Ru(η⁶-p-cymene)Cl₂] fragment, allows a series of bioactive carboxylic acids to be introduced directly into the organometallic molecule. Evaluation of the compounds on human ovarian cancer cells reveals synergistic enhancements in their antiproliferative activity relative to their bioactive organic and organometallic precursors.