A Lipophilic Pt(IV) Oxaliplatin Derivative Enhances Antitumor Activity

Pt(IV) complexes loaded hollow copper sulfide nanoparticles for tumor chemo/photothermal/photodynamic therapy

Hollow CuS nanoparticles can achieve photothermal and photodynamic therapy (PDT) in tumor treatment. However, excessive GSH in the tumor cells will consume the reactive oxygen species produced by PDT and reduce the PDT effect. Cisplatin is a broad-spectrum antineoplastic drug that can be used in a variety of tumor treatments. However, cisplatin is cytotoxic to normal cells while it kills tumor cells. Therefore, we construct Pt(IV) complexes loaded hollow CuS nanoparticles to attenuate the toxicity of cisplatin and enhance the PDT effect of the hollow CuS nanoparticles. The nanoparticles were proved to be able to accumulate around the tumor site through the enhanced permeability and retention (EPR) effect to achieve a synergistic chemo/photothermal/photodynamic therapy.

Effect of home-based resistance training on chemotherapy relative dose intensity and tolerability in colon cancer: The FORCE randomized control trial

BACKGROUND

Many patients with colon cancer cannot fully adhere to postoperative chemotherapy due to dose-limiting toxicities, resulting in lower relative dose intensity (RDI) and potentially compromising overall survival. This study examined whether home-based resistance training (RT) during adjuvant chemotherapy improves RDI and patient-reported toxicities versus usual care (UC) in colon cancer patients.

METHODS

Multicenter, randomized control trial (RCT) conducted at community and academic practices. Enrollment of patients receiving postoperative chemotherapy for colon cancer occurred between February 23, 2018, and September 29, 2021; final follow-up was March 21, 2022. Participants were randomized to RT (n = 90) or UC (n = 91) for the duration of chemotherapy. Participants in the RT group engaged in twice weekly home-based progressive RT. At the end of the study, UC was given an online exercise program.

RESULTS

Among 181 randomized patients (mean age, 55.2 [SD, 12.8] years, 95 [52.5%] were men), there were no differences in the mean RDI among those in RT (79% [SD, 19%]) and those in UC (82% [SD, 19%]); (mean difference -0.04 [95% confidence interval (CI), -0.09 to 0.02]). Assignment to RT did not significantly reduce the number of moderate/severe symptoms per week across follow-up (relative rate: 0.94 [95% CI, 0.72-1.22]). Additionally, time since randomization did not significantly modify the effect of RT on the overall number of symptoms (p = .06).

CONCLUSIONS

Among patients with colon cancer, these results do not support home-based RT as an adjunct to chemotherapy specifically to improve planned treatment intensity.

Body Composition, Relative Dose Intensity, and Adverse Events among Patients with Colon Cancer

BACKGROUND

Despite evidence that low muscle increases the risk of chemotoxicity, most chemotherapies are dosed on body surface area without considering body composition. Among 178 patients with colon cancer, we assessed muscle and adipose tissue with multiple techniques and examined their associations with relative dose intensity (RDI) and adverse events.

METHODS

We estimated (i) cross-sectional skeletal muscle area (SMA) and total adipose tissue (TAT) area at L3 from computed tomography (CT); (ii) appendicular lean mass (ALM) and total body fat (TBF) mass from dual-energy X-ray absorptiometry (DXA); and (iii) total body skeletal muscle mass using D3-creatine (D3Cr) dilution. We standardized each measurement by its sex-specific standard deviation (SD). The primary outcome was reduced RDI (RDI <85%). The secondary outcome was the number of moderate and severe adverse events during each cycle of chemotherapy. We estimated the associations of muscle and adipose tissue measurements (per SD increase) with reduced RDI using logistic regression and adverse events using generalized estimating equations for repeated measures.

RESULTS

Higher CT SMA and DXA ALM were significantly associated with a lower risk of reduced RDI [odds ratios: 0.56 (0.38-0.81) for CT SMA; 0.56 (0.37-0.84) for DXA ALM]. No measurements of muscle or adipose tissue were associated with adverse events.

CONCLUSIONS

More muscle was associated with improved chemotherapy completion among patients with colon cancer, whereas muscle and adipose tissue were not associated with adverse events.

IMPACT

Considering body composition may help personalize dosing for colon cancer chemotherapy by identifying patients at risk for poor chemotherapy outcomes.

Exploring the Impact of Head Group Modifications on the Anticancer Activities of Fatty-Acid-like Platinum(IV) Prodrugs: A Structure-Activity Relationship Study

We conducted the first comprehensive investigation on the impact of head group modifications on the anticancer activities of fatty-acid-like Pt(IV) prodrugs (FALPs), which are a class of platinum-based metallodrugs that target mitochondria. We created a small library of FALPs (1-9) with diverse head group modifications. The outcomes of our study demonstrate that hydrophilic modifications exclusively enhance the potency of these metallodrugs, whereas hydrophobic modifications significantly decrease their cytotoxicity. To further understand this interesting structure-activity relationship, we chose two representative FALPs (compounds 2 and 7) as model compounds: one (2) with a hydrophilic polyethylene glycol (PEG) head group, and the other (7) with a hydrophobic hydrocarbon modification of the same molecular weight. Using these FALPs, we conducted a targeted investigation on the mechanism of action. Our study revealed that compound 2, with hydrophilic modifications, exhibited remarkable penetration into cancer cells and mitochondria, leading to subsequent mitochondrial and DNA damage, and effectively eradicating cancer cells. In contrast, compound 7, with hydrophobic modifications, displayed a significantly lower uptake and weaker cellular responses. The collective results present a different perspective, indicating that increased hydrophobicity may not necessarily enhance cellular uptake as is conventionally believed. These findings provide valuable new insights into the fundamental principles of developing metallodrugs.

Visible light-activatable platinum(IV) prodrugs harnessing CD36 for ovarian cancer therapy

We hereby engineered photoactivatable Pt(IV) metallodrugs that harness CD36 to target ovarian cancer cells. Pt(IV) compounds mimic the structure of fatty acids and take advantage of CD36 as a "Trojan horse" to gain entry into the cells. We confirmed that CD36-dependent entry occurs using graphite furnace atomic absorption spectroscopy with ovarian cancer cells expressing different levels of CD36 and a CD36 inhibitor, SSO. Once the Pt(IV) metallodrugs enter the cancer cells, they can be activated to form Pt(II) with characteristics of cisplatin under visible light (490 nm) irradiation, promoting photoinduced electron transfer from the attached fluorophore to the metal center. This light-induced activation can increase the cytotoxicity of the Pt(IV) metallodrugs by up to 20 times toward ovarian cancer cells, inducing DNA damage and enabling efficient elimination of drug-resistant cancer cells.

Novel 4-Amino-Quinazoline Moieties Ligated Platinum(IV) Prodrugs Overcome Cisplatin Resistance in EGFRWT Human Lung Cancer

Developing bioactive axial ligands ligated platinum(IV) complexes with advantages over monotherapy and drug combinations is an efficient strategy to ameliorate the clinical defects of platinum(II) drugs. In this article, a series of 4-amino-quinazoline moieties (privileged pharmacophores of well-studied EGFR inhhibitors) ligated platinum(IV) were synthesized and evaluated for their anticancer activities. Among the complex, 17b demonstrated higher cytotoxicity against the tested lung cancer cells (including CDDP-resistant A549/CDDP cells) while lower cytotoxicity toward human normal cells than Oxaliplatin (Oxa) or cisplatin (CDDP). Mechanistic investigation demonstrated that the enhanced intracellular uptake of 17b efficiently elevated the of reactive oxygen species levels by 6.1 times more than Oxa. Detailed mechanisms of overcoming CDDP resistance revealed that 17b significantly induced apoptosis via inducing severe DNA damage, disturbing mitochondrial transmembrane potentials, efficiently disturbing EGFR-PI3K-Akt signaling transduction and activating a mitochondria-dependent apoptosis pathway. Besides, 17b significantly inhibited migration and invasion in A549/CDDP cells. In vivo tests exhibited that 17b obtained superior antitumor effect and attenuated systemic toxicity in A549/CDDP xenografts. All these results emphasized that the antitumor action of 17b differed from that of. classical platinum(II) drugs and provided a novel practical method to overcome CDDP resistance in lung cancer.

Supramolecular platinum complexes for cancer therapy

The rise of supramolecular chemistry offers new tools to design therapeutics and delivery platforms for biomedical applications. This review aims to highlight the recent developments that harness host-guest interactions and self-assembly to design novel supramolecular Pt complexes as anticancer agents and drug delivery systems. These complexes range from small host-guest structures to large metallosupramolecules and nanoparticles. These supramolecular complexes integrate the biological properties of Pt compounds and novel supramolecular structures, which inspires new designs of anticancer approaches that overcome problems in conventional Pt drugs. Based on the differences in Pt cores and supramolecular structures, this review focuses on five different types of supramolecular Pt complexes, and they include host-guest complexes of the FDA-approved Pt(II) drugs, supramolecular complexes of nonclassical Pt(II) metallodrugs, supramolecular complexes of fatty acid-like Pt(IV) prodrugs, self-assembled nanotherapeutics of Pt(IV) prodrugs, and self-assembled Pt-based metallosupramolecules.

Synthesis, Characterization and Biological Investigation of the Platinum(IV) Tolfenamato Prodrug–Resolving Cisplatin-Resistance in Ovarian Carcinoma Cell Lines

The research on the anticancer potential of platinum(IV) complexes represents one strategy to circumvent the deficits of approved platinum(II) drugs. Regarding the role of inflammation during carcinogenesis, the effects of non-steroidal anti-inflammatory drug (NSAID) ligands on the cytotoxicity of platinum(IV) complexes is of special interest. The synthesis of cisplatin- and oxaliplatin-based platinum(IV) complexes with four different NSAID ligands is presented in this work. Nine platinum(IV) complexes were synthesized and characterized by use of nuclear magnetic resonance (NMR) spectroscopy (1H, 13C, 195Pt, 19F), high-resolution mass spectrometry, and elemental analysis. The cytotoxic activity of eight compounds was evaluated for two isogenic pairs of cisplatin-sensitive and -resistant ovarian carcinoma cell lines. Platinum(IV) fenamato complexes with a cisplatin core showed especially high in vitro cytotoxicity against the tested cell lines. The most promising complex, 7, was further analyzed for its stability in different buffer solutions and behavior in cell cycle and cell death experiments. Compound 7 induces a strong cytostatic effect and cell line-dependent early apoptotic or late necrotic cell death processes. Gene expression analysis suggests that compound 7 acts through a stress-response pathway integrating p21, CHOP, and ATF3.

Combination of DNA Damage, Autophagy, and ERK Inhibition: Novel Evodiamine-Inspired Multi-Action Pt(IV) Prodrugs with High-Efficiency and Low-Toxicity Antitumor Activity

Exploring multi-targeting chemotherapeutants with advantages over single-targeting agents and drug combinations is of great significance in drug discovery. Herein, we employed phytogenic evodiamine (EVO) and conventional Pt(II) drugs to design and synthesize multi-target EVO-Pt(IV) anticancer prodrugs (4-14). Among them, compound 10 exhibited a 118-fold enhancement in the IC₅₀ value compared to cisplatin and low toxicity to normal cells. Further studies proved that 10 significantly enhanced intracellular Pt accumulation and DNA damage, perturbed mitochondrial membrane potential, inhibited cell migration and invasion, upregulated reactive oxygen species levels, and induced apoptosis and autophagic cell death. Molecular docking assay revealed that 10 fits perfectly into the extracellular signal-regulated protein kinase (ERK)-1 pocket, which was verified to produce profound ERK suppression. Most strikingly, compound 10 exhibited superior in vivo antitumor efficiency and effectively attenuated systemic toxicity. Our results emphasize that functionalizing platinum drugs with the multi-target EVO could generate synergistically excellent anticancer activity with low toxicity and decreased resistance, which may represent a brand-new cancer therapy modality.

Carboxylate-Capped Analogues of Ru265 Are MCU Inhibitor Prodrugs

The mitochondrial calcium uniporter (MCU) is a transmembrane protein that resides on the inner membrane of the mitochondria and mediates calcium uptake into this organelle. Given the critical role of mitochondrial calcium trafficking in cellular function, inhibitors of this channel have arisen as tools for studying the biological relevance of this process and as potential therapeutic agents. In this study, four new analogues of the previously reported Ru-based MCU inhibitor [ClRu(NH3)4(μ-N)Ru(NH3)4Cl]Cl3 (Ru265) are reported. These compounds, which bear axial carboxylate ligands, are of the general formula [(RCO2)Ru(NH3)4(μ-N)Ru(NH3)4(O2CR)]X3, where X = NO3- or CF3SO3- and R = H (1), CH3 (2), CH2CH3 (3), and (CH2)2CH3 (4). These complexes were fully characterized by IR spectroscopy, NMR spectroscopy, and elemental analysis. X-ray crystal structures of 1 and 3 were obtained, revealing the expected presence of both the linear Ru(μ-N)Ru core and axial formate and propionate ligands. The axial carboxylate ligands of complexes 1-4 are displaced by water in buffered aqueous solution to give the aquated compound Ru265'. The kinetics of these processes were measured by 1H NMR spectroscopy, revealing half-lives that span 5.9-9.9 h at 37 °C. Complex 1 with axial formate ligands underwent aquation approximately twice as fast as the other compounds. In vitro cytotoxicity and mitochondrial membrane potential measurements carried out in HeLa and HEK293T cells demonstrated that none of these four complexes negatively affects cell viability or mitochondrial function. The abilities of 1-4 to inhibit mitochondrial calcium uptake in permeabilized HEK293T cells were assessed and compared to that of Ru265. Fresh solutions of 1-4 are approximately 2-fold less potent than Ru265 with IC50 values in the range of 14.7-19.1 nM. Preincubating 1-4 in aqueous buffers for longer time periods to allow for the aquation reactions to proceed increases their potency of mitochondrial uptake inhibition to match that of Ru265. This result indicates that 1-4 are aquation-activated prodrugs of Ru265'. Finally, 1-4 were shown to inhibit mitochondrial calcium uptake in intact, nonpermeabilized cells, revealing their value as tools and potential therapeutic agents for mitochondrial calcium-related disorders.

Synthesis and characterization of thiocarbonato-linked platinum(IV) complexes

Herein we show the formation of new oxaliplatin-based platinum(IV) complexes by reaction with DSC-activated thiols via thiocarbonate linkage. Three model complexes based on aliphatic and aromatic thiols, as well as one complex with N-acetylcysteine as biologically active thiol were synthesized. This synthetic strategy affords the expansion of biologically active compounds other than those containing carboxylic, amine or hydroxy groups for coupling to the platinum(IV) center. The complexes were characterized by high-resolution mass spectrometry, NMR spectroscopy (¹H, ¹³C, ¹⁹⁵Pt) and elemental analysis. Their biological behavior was evaluated against two ovarian carcinoma cell lines and their cisplatin-resistant analogues. Remarkably, the platinum(IV) samples show modest in vitro cytotoxicity against A2780 cells and comparable effects against A2780cis cells. Two complexes in particular demonstrate improved activity against SKOV3cis cells. The reduction experiment of complex 8, investigated by UHPLC-HRMS, provides evidence of interesting platinum-species formed during reaction with ascorbic acid.

Cyclooxygenase-Inhibiting Platinum(IV) Prodrugs with Potent Anticancer Activity

Platinum(IV) prodrugs of the [Pt(P_L)(A_L)(COXi)(OH)]²⁺ type scaffold (where P_L is 1,10-phenanthroline or 5,6-dimethyl-1,10-phenanthroline, A_L is 1S,2S-diaminocyclohexane, and COXi is a COX inhibitor, either indomethacin or aspirin) were synthesised and characterised, and their biological activity was explored. MTT assays showed that these complexes exhibit outstanding activity against a range of cancer cell lines, and nanomolar activities were observed. The most potent complex, 4, exhibited a GI₅₀ of 3 nM in the Du145 prostate cancer cell line and was observed to display a 1614-fold increased activity against the HT29 colon cancer cell line relative to cisplatin. ICP-MS studies showed a linear correlation between increased cellular accumulation of the complexes and increased cytotoxicity, while an enzyme immunoassay showed that 1 and 2 inhibited COX-2 at 14 and 1.4 µM, respectively, which is comparable to the inhibition exhibited by indomethacin. These results suggest that while the cytotoxicity of prodrugs 1–4 was influenced by cellular uptake, it was not entirely dependent on either COX inhibition or lipophilicity.

Copper(II) Complexes of Halogenated Quinoline Schiff Base Derivatives Enabled Cancer Therapy through Glutathione-Assisted Chemodynamic Therapy and Inhibition of Autophagy Flux

Twelve new complexes Cu(L¹)₂-Cu(L¹²)₂ were designed and synthesized to improve their chemotherapeutic properties. They showed considerable antiproliferative activity against T24 cancer cells but lower cytotoxicity to human normal cells HL-7702 and WI-38. A mechanism study indicated that Cu(L⁴)₂ and Cu(L¹⁰)₂ were reduced to Fenton-like Cu⁺ by glutathione depletion, and the resulting Cu⁺ catalyzed the generation of highly toxic hydroxyl radicals from excess H₂O₂. Simultaneously, Cu(L⁴)₂ and Cu(L¹⁰)₂ could decrease the catalase activity to restrain H₂O₂ transfer to H₂O for enhanced chemodynamic therapy (CDT). These induced mitochondrial dysfunctions and endoplasmic reticulum stress to induce T24 cell apoptosis. In addition, Cu(L⁴)₂ and Cu(L¹⁰)₂ inhibited autophagy flux to promote cell apoptosis. Cu(L⁴)₂ and Cu(L¹⁰)₂ demonstrated strong tumor inhibition ability in the T24 xenograft model. Moreover, Cu(L¹⁰)₂ showed higher antitumor activity and a better safety profile than the CDT agent Cu1. Cu(L¹⁰)₂ exhibited excellent pharmacokinetic properties. Collectively, Cu(L⁴)₂ and Cu(L¹⁰)₂ could be developed as potential CDT candidates for cancer treatment.

Ptxplatin: a multifunctional Pt(iv) antitumor prodrug

Ptxplatin, comprising paclitaxel and cisplatin, intervened in several cellular processes including the p53 apoptosis pathway, mitochondrial damage and ER stress to kill cancer cells.

Analytical methods for the quantification of cisplatin, carboplatin, and oxaliplatin in various matrices over the last two decades

Background:

Platinum derivatives including cisplatin and its later generations carboplatin, and oxaliplatin remain the most largely used drugs in the therapy of malignant diseases. They exert notable anticancer activity towards numerous types of solid tumors such as gastric, colorectal, bladder, ovary, and several others. The chemotherapeutic activity of these compounds, however, is associated with many unwanted side effects and drug resistance problems limiting their application and effectiveness. Proper dosage is still an inherent problem, as these drugs are usually prescribed in small doses.

Objective:

Several analytical methods have been reported for the accurate quantification of cisplatin, carboplatin, and oxaliplatin and their metabolites either alone or in combination with other chemotherapeutic drugs, in different matrices such as pharmaceutical formulations, biological fluids, cancer cells, and environmental samples. The main goal of this review is to systematically study the analytical methods already used for the analysis of cisplatin, carboplatin, and oxaliplatin in various matrices during the last two decades.

Results and Conclusion:

In the literature, reviews showed that numerous analytical methods such as electroanalytical, UV-visible spectrophotometry, chromatographic, fluorescence, atomic absorption spectrophotometry, and other spectroscopic methods combined with mass spectrometry were used for the determination of these compounds in various matrices.

Co(II) complexes of curcumin and a ferrocene-based curcuminoid: a study on photo-induced antitumor activity

Co(II) complexes having a ferrocene-based curcuminoid (Fc-curH) ligand viz. [Co(L)₂(Fc-cur)]ClO₄ (1, 2), where L is phenanthroline base, namely, 1,10-phenanthroline (phen in 1) and dipyrido[3,2-a:2',3'-c]phenazine (dppz in 2) have been synthesized, characterized and evaluated as photochemotherapeutic agents in vitro. The corresponding Co(II) complexes of the naturally occurring polyphenol curcumin (curH), namely, [Co(L)₂(cur)]ClO₄ (3, 4), where L is phen (in 3) and dppz (in 4) were synthesized and their photo-induced anticancer activities compared with their ferrocene containing counterparts 1 and 2. The Co(II) acetylacetonato complex viz. [Co(phen)₂(acac)]ClO₄ (5) was structurally characterized through X-ray crystallography and used as control for cellular experiments. The Co(II) complexes having ferrocene-based curcuminoid are remarkably stable at physiological condition with higher lipophilicity compared to their curcumin analogues. The complexes display significant binding propensity to calf thymus (ct) DNA and human serum albumin (HSA). The complexes 1-4 display remarkable visible light induced cytotoxicity with the ferrocenyl analogues showing more phototoxic index (PI). The Co(II) curcumin complexes localize in the nucleus and mitochondria of A549 cells. The primary cell death mechanism is believed to be apoptotic in nature induced by light assisted generation of reactive oxygen species (ROS).Graphic abstract.

Biodistribution and efficacy of the anticancer drug, oxaliplatin palmitate acetate, in mice

Oxaliplatin palmitate acetate (OPA), a platinum (IV) oxaliplatin derivative, was previously designed with the aim to improve the platinum-based anti-cancer therapy. In this work, we further explore the potential of OPA in extensive in vitro and in vivo studies. OPA in pancreatic (BxPC3-luc), lung (NCI-H1993) and liver (Hep3B) cancer cell lines showed a higher toxicity in comparison to oxaliplatin. The in vitro release kinetic experiments of OPA from the nanoparticles (NPs) under sink conditions exhibited a very rapid profile. Furthermore, OPA cannot be considered a prodrug of oxaliplatin, based on the OPA intact molecule pharmacokinetic profile study in rats. The formation of oxaliplatin from the biodegradation of OPA ranges only from 5% to 7% and both drugs were rapidly eliminated from the plasma. Pharmacokinetics of OPA PLGA nanoparticles in mice showed that nanoparticles failed to prolong the release of OPA in the plasma and did not add any therapeutic benefit over OPA solution, as suggested by the rapid in vitro release of OPA from nanoparticles. In pancreatic xenograft BxPC3-luc cancer model, both OPA in solution and OPA nanoparticles inhibited the tumor growth, equally and significantly, as compared to oxaliplatin. In liver xenograft Hep3B cancer model, OPA solution and cisplatin demonstrated good and similar antitumor efficacy. In lung xenograft NCI-H1993 cancer model, OPA solution, with a significant antitumor efficacy, was superior to cisplatin, which did not differ from the vehicle. In conclusion, OPA may offer a promising advance in platinum-based chemotherapy against various forms of cancers in an adequate dose and schedule.

Methodology for characterization of platinum-based drug's targeted delivery nanosystems

Conventional anticancer therapies exploiting platinum-based drugs rely principally on the intravascular injection of the therapeutic agent. The anticancer drug is distributed throughout the body by the systemic blood circulation undergoing cellular uptake, rapid clearance and excretion. Consequently, only a small portion of the platinum-based drug reaches the tumor site, which is associated with severe side effects. For this reason, targeted delivery systems are of great need since they offer enhanced and selective delivery of a drug to cancerous cells making the therapy safe and more effective. Up to date, a variety of the Pt-based drug targeted delivery systems (Pt-based DTDSs) utilizing nanomaterials have been developed and tested using a range of analytical techniques that provided essential information on their synthesis, stability, biodistribution and cytotoxicity. Here we summarize those experimental techniques indicating their applicability at different stages of the research, as well as pointing out their strengths, advantages, drawbacks and limitations. Also, the existing strategies and approaches are critically reviewed with the objective to reveal and give rise to the development of the analytical methodology suitable for reliable Pt-based DTDSs characterization which would eventually result in novel therapies and better patients' outcomes.

Synthesis and biological evaluation of novel artemisone-piperazine-tetronamide hybrids

For the first time, six novel artemisone-piperazine-tetronamide hybrids (12a-f) were efficiently synthesised from dihydroartemisinin (DHA) and investigated for their in vitro cytotoxicity against some human cancer cells and benign cells. All the targets showed good cytotoxic activity in vitro. Hybrid 12a exhibited much better inhibitory activity against human liver cancer cell line SMMC-7721 (IC₅₀ = 0.03 ± 0.04 μM for 24 h) than the parent DHA (IC₅₀ > 0.7 μM), and two references, vincristine (VCR; IC₅₀ = 0.27 ± 0.03 μM) & cytosine arabinoside (ARA; IC₅₀ = 0.63 ± 0.04 μM). Furthermore, hybrid 12a had low toxicity against human benign liver cell line LO2 (IC₅₀ = 0.70 ± 0.02 μM for 24 h) compared with VCR, ARA, and DHA in vitro. Moreover, the inhibitory activity of hybrid 12a was obviously enhanced when human liver cancer cell line MHCC97H absorbed Fe²⁺ in vitro.

Biomimetic clotrimazole-loaded PLGA films with enhanced adhesiveness for controlled drug release

Biomimetic adhesive surfaces have a number of potential applications in the pharmaceutical and biomedical fields. Fabrication techniques must be adapted to biocompatible and biodegradable materials required for controlled drug release applications. In this study biomimetic adhesive poly(lactic-co-glycolic acid) (PLGA) films loaded with different concentrations of clotrimazole (CTZ) were prepared without combining other adhesive excipients as a controlled release system for potential local oral drug delivery. The films were fully characterized from morphological point of view, and CTZ-loaded biomimetic films exhibited adequate surface pH values, high drug encapsulation efficiency, and loading content. The adhesion strength of the obtained films was significantly higher compared to a flat film reference under different contact conditions. Thermal analysis indicated a decrease of drug crystallinity upon incorporation into PLGA films. The in vitro release of CTZ from PLGA biomimetic films was tested in simulated saliva, and it exhibited an initial burst release, accompanied by a sustained release phase over 10 days. Finally, the mucoadhesive properties of the obtained films was studied using agar/mucin plate as a representative mucosal substrate, and the results demonstrated superior mucoadhesion potential of CTZ-loaded biomimetic film in comparison to its flat counterpart. Having demonstrated the ability to load CTZ into PLGA biomimetic films with enhanced adhesion capacity, the potential use in local oral drug delivery applications warrants further in vitro and in vivo investigations.

Use of Half-Generation PAMAM Dendrimers (G0.5–G3.5) with Carboxylate End-Groups to Improve the DACHPtCl2 and 5-FU Efficacy as Anticancer Drugs

The DACHPtCl2 compound (trans-(R,R)-1,2-diaminocyclohexanedichloroplatinum(II)) is a potent anticancer drug with a broad spectrum of activity and is less toxic than oxaliplatin (trans-l-diaminocyclohexane oxalate platinum II), with which it shares the active metal fragment DACHPt. Nevertheless, due to poor water solubility, its use as a chemotherapeutic drug is limited. Here, DACHPtCl2 was conjugated, in a bidentate form, with half-generation PAMAM dendrimers (G0.5–G3.5) with carboxylate end-groups, and the resulting conjugates were evaluated against various types of cancer cell lines. In this way, we aimed at increasing the solubility and availability at the target site of DACHPt while potentially reducing the adverse side effects. DNA binding assays showed a hyperchromic effect compatible with DNA helix’s disruption upon the interaction of the metallodendrimers and/or the released active metallic fragments with DNA. Furthermore, the prepared DACHPt metallodendrimers presented cytotoxicity in a wide set of cancer cell lines used (the relative potency regarding oxaliplatin was in general high) and were not hemotoxic. Importantly, their selectivity for A2780 and CACO-2 cancer cells with respect to non-cancer cells was particularly high. Subsequently, the anticancer drug 5-FU was loaded in a selected metallodendrimer (the G2.5COO(DACHPt)16) to investigate a possible synergistic effect between the two drugs carried by the same dendrimer scaffold and tested for cytotoxicity in A2780cisR and CACO-2 cancer cell lines. This combination resulted in IC50 values much lower than the IC50 for 5-FU but higher than those found for the metallodendrimers without 5-FU. It seems, thus, that the metallic fragment-induced cytotoxicity dominates over the cytotoxicity of 5-FU in the set of considered cell lines.

Use of Half-Generation PAMAM Dendrimers (G0.5-G3.5) with Carboxylate End-Groups to Improve the DACHPtCl2 and 5-FU Efficacy as Anticancer Drugs

The DACHPtCl₂ compound (trans-(R,R)-1,2-diaminocyclohexanedichloroplatinum(II)) is a potent anticancer drug with a broad spectrum of activity and is less toxic than oxaliplatin (trans-l-diaminocyclohexane oxalate platinum II), with which it shares the active metal fragment DACHPt. Nevertheless, due to poor water solubility, its use as a chemotherapeutic drug is limited. Here, DACHPtCl₂ was conjugated, in a bidentate form, with half-generation PAMAM dendrimers (G0.5-G3.5) with carboxylate end-groups, and the resulting conjugates were evaluated against various types of cancer cell lines. In this way, we aimed at increasing the solubility and availability at the target site of DACHPt while potentially reducing the adverse side effects. DNA binding assays showed a hyperchromic effect compatible with DNA helix's disruption upon the interaction of the metallodendrimers and/or the released active metallic fragments with DNA. Furthermore, the prepared DACHPt metallodendrimers presented cytotoxicity in a wide set of cancer cell lines used (the relative potency regarding oxaliplatin was in general high) and were not hemotoxic. Importantly, their selectivity for A2780 and CACO-2 cancer cells with respect to non-cancer cells was particularly high. Subsequently, the anticancer drug 5-FU was loaded in a selected metallodendrimer (the G2.5COO(DACHPt)₁₆) to investigate a possible synergistic effect between the two drugs carried by the same dendrimer scaffold and tested for cytotoxicity in A2780cisR and CACO-2 cancer cell lines. This combination resulted in IC₅₀ values much lower than the IC₅₀ for 5-FU but higher than those found for the metallodendrimers without 5-FU. It seems, thus, that the metallic fragment-induced cytotoxicity dominates over the cytotoxicity of 5-FU in the set of considered cell lines.

Multifunctional polymeric micellar nanomedicine in the diagnosis and treatment of cancer

Polymeric micelles are a prevalent topic of research for the past decade, especially concerning their fitting ability to deliver drug and diagnostic agents. This delivery system offers outstanding advantages, such as biocompatibility, high loading efficiency, water-solubility, and good stability in biological fluids, to name a few. The multifunctional polymeric micellar architect offers the added capability to adapt its surface to meet the looked-for clinical needs. This review cross-talks the recent reports, proof-of-concept studies, patents, and clinical trials that utilize polymeric micellar family architectures concerning cancer targeted delivery of anticancer drugs, gene therapeutics, and diagnostic agents. The manuscript also expounds on the underlying opportunities, allied challenges, and ways to resolve their bench-to-bedside translation for allied clinical applications.

Synthesis and anticancer activity of mixed ligand 3d metal complexes

Our previously reported copper-based complexes of tropolone show nice antitumor effects, but with high cytotoxicity to normal cells, which is presumably caused by copper ions. Here, we managed to achieve this challenge by using other 3D metals to replace copper ions. We thus prepared four mononuclear 3D metal complexes [M(phen)L2] (M = Mn, Co, Ni, and Zn for 1-4, respectively). Complexes 1 and 4 show selectivity on different cancer cell lines with much lower cytotoxicity to normal cells than cisplatin. The anticancer effects for complexes 2 and 3 on the tested cancer cell lines are very poor. It revealed a tuning effect of different metal ions on the anticancer activities with those for Mn(II) and Zn(II) being much higher than those for Co(II) and Ni(II) in this system. Among them, complex 1 presents a best anticancer effect on HeLa cells comparable to cisplatin. It overcame the afore-mentioned shortage of high cytotoxicity to normal cells for the reported Cu(II) complexes. It revealed from the mechanistic studies that complex 1 mainly induces apoptosis through the mitochondrial pathway by increasing intracellular reactive oxygen species, releasing Ca2+, and activating Caspase 9 and proapoptotic gene Bax.

Systematically altering the lipophilicity of rhenium(I) tricarbonyl anticancer agents to tune the rate at which they induce cell death

Rhenium-based anticancer agents have arisen as promising alternatives to conventional platinum-based drugs. Based on previous studies demonstrating how increasing lipophilicity improves drug uptake within the cell, we sought to investigate the effects of lipophilicity on the anticancer activity of a series of six rhenium(i) tricarbonyl complexes. These six rhenium(i) tricarbonyl structures, called Re-Chains, bear pyridyl imine ligands with different alkyl chains ranging in length from two to twelve carbons. The cytotoxicities of these compounds were measured in HeLa cells. At long timepoints (48 h), all compounds are equally cytotoxic. At shorter time points, however, the compounds with longer alkyl chains are significantly more active than those with smaller chains. Cellular uptake studies of these compounds show that they are taken up via both passive and active pathways. Collectively, these studies show how lipophilicity affects the rate at which these Re compounds induce their biological activities.

Multifunctional tumor-targeted PLGA nanoparticles delivering Pt(IV)/siBIRC5 for US/MRI imaging and overcoming ovarian cancer resistance

Cisplatin (Pt(II)) resistance is an important factor in the high mortality rates of ovarian cancer. Herein, we synthesized multifunctional tumor-targeted poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs-cRGD) for monitoring therapeutic effects by dual-mode imaging and overcoming cisplatin resistance. Uniformly sized NPs-cRGD demonstrated controlled and sustained release of drugs and genes, excellent gene loading and gene protection capacity, good storage stability and no serum-induced aggregation in vitro. NPs-cRGD demonstrated clear, targeting and prolonged ultrasound imaging and magnetic resonance imaging (MRI) in vivo. The targeting of NPs-cRGD combined with ultrasound facilitated nanoparticle penetrattion into cells; entry was time-dependent. NPs-cRGD escaped from lysosomes, thereby preventing siBIRC5 degradation, which enabled siBIRC5 to efficiently inhibit the antiapoptosis effects of BIRC5 in SKO3-DDP to overcome the antiapoptosis properties of resistant cells. Furthermore, Pt(IV) in NPs-cRGD exhausted glutathione (GSH), thereby increasing drug accumulation to effectively increase Pt(II) levels. The subsequent combination of Pt(II) with DNA prevented the expressions of genes and upregulated the expression of p53 to induce the mitochondria apoptosis pathway. The reduced GSH activity and the generation of Pt(II) further promoted high levels of reactive oxygen species (ROS) to induce cell apoptosis. Therefore, NPs-cRGD with ultrasound promoted the apoptosis of resistant ovarian cancer cells by multiple mechanisms, including increased cellular drug accumulation, reversed antiapoptotic effects by siBIRC5, and enhanced ROS levels. In a tumor-bearing nude mice model, NPs-cRGD with US demonstrated excellent tumor-targeting, high efficiency tumor inhibition and low systemic toxicity. Therefore, NPs-cRGD provides a means to monitor treatment processes and can be combined with ultrasound treatment to overcome ovarian cancer resistance in vitro and in vivo.

Supramolecular combination chemotherapy: a pH-responsive co-encapsulation drug delivery system

Most cancer chemotherapy regimens rely on the use of two or more chemotherapeutic agents. However, achieving the best possible dosing of the individual drugs can be challenging due to differences in metabolism, uptake, and clearance among other factors. Here we describe a supramolecular strategy for achieving drug delivery in which the loading ratio of two active components is easily defined. Specifically, we report the formation of aggregates comprised of self-assembled amphiphiles between carboxylatopillar[6]arene (CP6A) and an oxaliplatin (OX)-type Pt(iv) prodrug (PtC10). The association constant (K a) for the underlying host-guest interaction at pH 7.4 ((1.16 ± 0.03) × 104 M-1) is an order of magnitude higher than at pH 5.0 ((1.73 ± 0.15) × 103 M-1). A second chemotherapeutic, doxorubicin (DOX), may be encapsulated in the resulting vesicles (PtC10⊂CP6A) to give a supramolecular combination chemotherapeutic system DOX@PtC10⊂CP6A. Drug release studies served to confirm that PtC10 and DOX are released in acidic environments. Support for a synergistic antiproliferative effect relative to PtC10 + DOX came from cellular studies of DOX@PtC10⊂CP6A using the human liver hepatocellular carcinoma (HepG-2) cell line. In vivo studies revealed that DOX@PtC10⊂CP6A is not only able to retard tumor growth efficiently but also reduce drug-related toxic side effects in BALB/c nude mice bearing HepG-2 subcutaneous tumor xenografts. These favorable findings are attributed to the formation of a ternary complex that benefits from an enhanced permeability and retention (EPR) effect in vivo while allowing for the pH-based release of PtC10 and DOX at the tumor site.

A Pt(IV)-based mononitro-naphthalimide conjugate with minimized side-effects targeting DNA damage response via a dual-DNA-damage approach to overcome cisplatin resistance

Platinum(Pt)(II) drugs and new Pt(IV) agents behave the dysregulation of apoptosis as the result of DNA damage repair and thus, are less effective in the treatment of resistant tumors. Herein, mononitro-naphthalimide Pt(IV) complex 10b with minimized side-effects was reported targeting DNA damage response via a dual-DNA-damage approach to overcome cisplatin resistance. 10b displayed remarkably evaluated antitumor (70.10%) activities in vivo compared to that of cisplatin (52.88%). The highest fold increase (FI) (5.08) for A549cisR cells and the lowest (0.72) for A549 indicated 10b preferentially accumulated in resistant cell lines. The possible molecular mechanism indicates that 10b targets resistant cells in a totally different way from the existing Pt drugs. The cell accumulation and the Pt levels in genomic DNA from 10b is almost 5 folds higher than that of cisplatin and oxaliplatin, indicating the naphthalimide moiety in 10b exhibits preferentially DNA damage. Using 5'-dGMP as a DNA model, the DNA-binding properties of 10b (1 mM) with 5'-dGMP (3 mM) in the presence of ascorbic acid (5 mM) deduced that 10b was generated by the combination of cisplatin with 5'-dGMP after reduction by ascorbic acid. Moreover, 10b promoted the expression of p53 gene and protein more effectively than cisplatin, leading to the increased anticancer activity. The up-regulated γH2A.X and down-regulated RAD51 indicates that 10b not only induced severe DNA damage but also inhibited the DNA damage repair, thus resulting in its higher cytotoxicity in comparison to that of cisplatin. Their preferential accumulation in cancer cells (SMMC-7721) compared to the matched normal cells (HL-7702 cells) demonstrated that they were potentially safe for clinical therapeutic use. In addition, the higher therapeutic indices of 10b for 4T1 cells in vivo indicated that naphthalimide-Pt(IV) conjugates behaved a vital function in the treatment of breast cancer. For the first time, our study implies a significant strategy for Pt drugs to treat resistance cancer targeting DNA damage repair via dual DNA damage mechanism in a totally new field.

Developing Biodegradable Nanoparticles Loaded with Mometasone Furoate for Potential Nasal Drug Delivery

Intranasal drug administration is considered a routine in the treatment of many nasal conditions including chronic rhinosinusitis (CRS), which is a common disease involving long-term inflammation of the nasal mucosa. Topical nasal steroid treatment is safe and easy to use and plays a basic role in both nonsurgical and surgical treatments for CRS. Intranasal steroid therapy for various time intervals is commonly used before and after endoscopic CRS nasal surgeries to reduce inflammation and edema and to improve mucosal healing. The medication is currently administered via conventional nasal sprays; therefore, there is an incentive to develop more efficient drug delivery systems for the controlled release of topical steroids into the sinonasal cavities over a prolonged period of time. In this study, poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) loaded with mometasone furoate (MF) were generated using the nanoprecipitation method and characterized physicochemically and morphologically. MF NPs exhibited adequate physicochemical properties and high drug encapsulation efficiency and loading content. MF exhibited sustained release from NPs over 7 days in vitro with an initial burst release; various mathematical models were applied to determine the kinetics of drug release. Having demonstrated the ability to load MF in PLGA-NPs using the nanoprecipitation method for the first time, these NPs urge the need for additional investigations to demonstrate their therapeutic potential in nasal delivery applications.

Targeting drug delivery system for platinum(Ⅳ)-Based antitumor complexes

Classical platinum(II) anticancer agents are widely-used chemotherapeutic drugs in the clinic against a range of cancers. However, severe systemic toxicity and drug resistance have become the main obstacles which limit their application and effectiveness. Because divalent cisplatin analogues are easily destroyed in vivo, their bioavailability is low and no selective to tumor tissues. The platinum(IV) prodrugs are attractive compounds for cancer treatment because they have great advantages, e.g., higher stability in biological media, aqueous solubility and no cross-resistance with cisplatin, which may become the next generation of platinum anticancer drugs. In addition, platinum(IV) drugs could be taken orally, which could be more acceptable to cancer patients, breaking the current situation that platinum(II) drugs can only be given by injection. The coupling of platinum(IV) complexes with tumor targeting groups avoids the disadvantages such as instability in blood, irreversible binding to plasma proteins, rapid renal clearance, and non-specific distribution in normal tissues. Because of the above advantages, the combination of platinum complexes and tumor targeting groups has become the hottest field in the research and development of new platinum drugs. These approaches can be roughly categorized into two groups: active and passive targeted strategies. This review concentrates on various targeting and delivery strategies for platinum(IV) complexes to improve the efficacy and reduce the side effects of platinum-based anticancer drugs. We have made a summary of the related articles on platinum(IV) targeted delivery in recent years. We believe the results of the studies described in this review will provide new ideas and strategies for the development of platinum drugs.

Palladium(ii) complexes with thiosemicarbazones derived from pyrene as topoisomerase IB inhibitors

New palladium complexes with thiosemicarbazonate ligands derived from pyrene exhibit potent antiproliferative activity against A2780 and cisplatin-resistant A2780Cis human ovarian cancer cells, which is dependent on substituent groups of the thiosemicarbazone ligands. Cellular accumulation and distribution studies confirmed that palladium enters the cell nucleus. DNA and topoisomerase IB studies show that one complex is a potent TopIB inhibitor, with selectivity for cancer versus normal cells.

Synthesis of 2-deoxy-d-glucose coated Fe3O4 nanoparticles for application in targeted delivery of the Pt(iv) prodrug of cisplatin – a novel approach in chemotherapy

Pt(IV) prodrug of cisplatin was loaded on 2DG functionalized silica coated Fe₃O₄ nanoparticles. The formulation alone exhibited biocompatibility whereas Pt(IV) loaded formulation exhibited cytotoxicity comparable with cisplatin.

A class of Pt(iv) triple-prodrugs targeting nucleic acids, thymidylate synthases and histone deacetylases

A Pt(iv)-triple-prodrug, comprising VPA, 5-FU, regulated TS, HDAC, and γH2AX, showing higher efficiency and lower toxicity than cisplatin.

Improving the anticancer activity of platinum(iv) prodrugs using a dual-targeting strategy with a dichloroacetate axial ligand

Four novel platinum(iv) complexes, characteristic of DCA/TFA and with chloride ions as axial ligands, were designed and synthesized. This type of platinum(iv) complexes 1a–2b exhibited significant cytotoxic activity, and the cytotoxicity of 1b was the greatest among these four complexes, which was 20.61 fold and 7.65 fold higher than that of cisplatin against HepG-2 and NCI-H460 cancer cells, respectively. The result from the apoptosis assay of 1b was consistent with the result from the cytotoxicity assay. In addition, complexes 1a and 1b induced cell cycle arrest at the S phase on HepG-2 cells. Taken together, our data showed that Pt(iv) complex 1b released the corresponding Pt(ii) complex and DCA, and induced apoptosis as well as disruption of the mitochondrial membrane potential, establishing Pt(iv) complex 1b as a potential dual-targeting anticancer agent.

Complex 1b could release complex B and DCA, playing a dual-targeting anti-tumor effect against cancer cells, targeting nuclear DNA and mitochondria, respectively.

Fuplatin: An Efficient and Low-Toxic Dual-Prodrug

As FDA-approved chemotherapeutic agents, cisplatin, oxaliplatin, and 5-fluorouracil are widely used in clinic but limited by severe side-effects. To ameliorate their respective defects, a series of "dual-prodrug" by linking oxoplatin and 5-FU were designed and synthesized. The assembled compounds 10-17, named Fuplatin, exhibited much higher cytotoxicity against the tested cancer cells while lower cytotoxicity toward the human normal lung cells than free drugs or their combinations. Among them, 14 enhanced cellular accumulation with 62- and 825-fold amount of oxaliplatin and 8 at 9 h, respectively, significantly induced DNA damage and cell apoptosis, and inhibited migration and invasion in HCT-116 cells. Compound 14 arrested the cell cycle at S and G2 phases and up-regulated thymidylate synthase and p53, consistent with the results of the combination, suggesting 14 adopted a collaborative mode of 5-FU and oxaliplatin to kill cancer cells. In vivo, compound 14 showed high antitumor effect and no observable toxicity in NOD/SCID mice bearing HCT-116 tumors.

Pt(IV) Bifunctional Prodrug Containing 2-(2-Propynyl)octanoato Axial Ligand: Induction of Immunogenic Cell Death on Colon Cancer

The synthesis, characterization, and in vitro activity of a cyclohexane-1 R,2 R-diamine-based Pt(IV) derivative containing the histone deacetylase inhibitor rac-2-(2-propynyl)octanoato, namely, ( OC-6-44)-acetatodichlorido(cyclohexane-1 R,2 R-diamine)( rac-2-(2-propynyl)octanoato)platinum(IV), are reported together with those of its isomers containing enantiomerically enriched axial ligands. These Pt(IV) complexes showed comparable activity, of 2 orders of magnitude higher than reference drug oxaliplatin on three human (HCT 116, SW480, and HT-29) and one mouse (CT26) colon cancer cell lines. In vivo experiments were carried out on immunocompetent BALB/c mice bearing the same syngeneic tumor. The complex ( OC-6-44)-acetatodichlorido(cyclohexane-1 R,2 R-diamine)( rac-2-(2-propynyl)octanoato)platinum(IV) showed higher tumor mass Pt accumulation than oxaliplatin, due to its higher lipophilicity, with negligible nephro- and hepatotoxicities when administered intravenously. A remarkable tumor mass invasion by cytotoxic CD8+ T lymphocytes, following the Pt(IV) treatment, indicated a strong induction of immunogenic cell death.

Synthesis and characterization of cyclohexane-1R,2R-diamine-based Pt(iv) dicarboxylato anticancer prodrugs: their selective activity against human colon cancer cell lines

Three pairs of asymmetric dicarboxylato derivatives based on the cisplatin and oxaliplatin-like skeletons have been synthesized de novo or re-synthesized. The axial ligands consist of one medium-chain fatty acid (MCFA), namely clofibrate (i.e. 2-(p-chlorophenoxy)-2-methylpropionic acid, CA), heptanoate (HA) or octanoate (OA), respectively, and an inactive acetato ligand that imparts acceptable water solubility to such conjugates. Stability tests provided evidence for the partial formation of two hydrolyzed products, corresponding to two monoaqua diastereomers derived from the substitution of an equatorial chlorido ligand with a water molecule. The complexes have been tested on three different colon cancer cell lines having different histological history, and also on the cisplatin-sensitive A2780 ovarian cancer cell line for comparison. This allowed the evaluation not only of the increase in activity on passing from Pt(ii) to Pt(iv) derivatives, but also the selectivity towards colon cancer cells brought about by the cyclohexane-1R,2R-diamine carrier ligand.

Synthesis of monofunctional platinum(iv) carboxylate precursors for use in Pt(iv)-peptide bioconjugates

Herein we present platinum(iv) bioconjugates with polyarginine peptides as prospective prodrug delivery systems. Asymmetrical platinum(iv) complexes 3 were obtained via oxidation of parent platinum(ii) complexes 2 with N-bromosuccinimide (NBS) in the presence of succinic anhydride. The combination of these two oxidation reagents furnishes the platinum(iv) environment with two different axial ligands, one of which bears a free carboxylic acid. All platinum(ii) and (iv) compounds were characterized by FT-IR, ESI-MS, HPLC, ¹H-, ¹³C- and ¹⁹⁵Pt-NMR. Standard solid-phase peptide chemistry was used for the synthesis of polyarginine (R₉) peptides. Coupling of the platinum complexes with peptides N-terminally afforded peptide monoconjugates, which were purified by semi-preparative HPLC and characterized by analytical HPLC and ESI-MS. Platinum(iv)-peptide bioconjugates as well as platinum(ii) and platinum(iv) complexes were tested as cytotoxic agents against two different human cancer cell lines (MCF-7, HepG2) and normal human fibroblasts cell lines (GM5657T). Preliminary in vitro data showed that all platinum(iv) complexes exhibit lower activity than their platinum(ii) precursors towards most cell lines. Interestingly, in the case of HepG2 cells, the Pt(iv)-(R)₉-G-A-L bioconjugate (4a) showed even higher activity compared to the non-targeting platinum(iv) parent compound.