Reactive oxygen species and glutathione dual responsive nanoparticles for enhanced prostate cancer therapy

Facile construction of gefitinib-loaded zeolitic imidazolate framework nanocomposites for the treatment of different lung cancer cells

Gefitinib (GET) is a revolutionary targeted treatment inhibiting the epidermal growth factor receptor's tyrosine kinase action by competitively inhibiting the ATP binding site. In preclinical trials, several lung cancer cell lines and xenografts have demonstrated potential activity with GET. Response rates neared 25% in preclinical trials for non-small cell lung cancer. Here, we describe the one-pot synthesis of GET@ZIF-8 nanocomposites (NCs) in pure water, encapsulating zeolitic imidazolate framework 8 (ZIF-8). This method developed NCs with consistent morphology and a loading efficiency of 9%, resulting in a loading capacity of 20 wt%. Cell proliferation assay assessed the anticancer effect of GET@ZIF-8 NCs on A549 and H1299 cells. The different biochemical staining (Calcein-AM and PI and 4',6-Diamidino-2-phenylindole nuclear staining) assays assessed the cell death and morphological examination. Additionally, the mode of apoptosis was evaluated by mitochondrial membrane potential (∆ψm) and reactive oxygen species. Therefore, the study concludes that GET@ZIF-8 NCs are pledged to treat lung cancer cells.

The effect of SP/NK1R on expression and activity of glutaredoxin and thioredoxin proteins in prostate cancer cells

Substance P (SP), an important neuropeptide, has a crucial role in the progression of several cancers, including prostate cancer, through interacting with the neurokinin-1 receptor (NK1R). Oxidative stress is also involved in the onset and progression of prostate cancer. However, no studies have been performed on the cross-talk between the SP/NK1R system and cellular redox balance in prostate cancer, and how it is involved in tumorogenesis. We aimed to investigate the effect of the SP/NK1R system and the blockage of NK1R with its specific antagonist (aprepitant) on the cellular redox status of the prostate cancer cell line (PC3 and LNCaP). We performed the resazurin assay to evaluate the toxicity of the aprepitant on the PC3 and LNCaP cell lines. The intracellular reactive oxygen species (ROS) level was measured after SP and aprepitant treatment. The alterations of expression and activity of two crucial cellular oxidoreductases, glutaredoxin, and thioredoxin were evaluated by qRT-PCR and commercial kits (ZellBio GmbH), respectively. Our results revealed that SP increased ROS production and decreased the expression and activity of glutaredoxin and thioredoxin. On the other hand, treatment of cells with aprepitant showed reverse results. In conclusion, we found that the SP/NK1R system could promote prostate cancer progression by inducing oxidative stress. In addition, the inhibition of NK1R by aprepitant modulated the effect of the SP/NK1R system on the cellular redox system. Aprepitant might therefore be introduced as a candidate for the treatment of prostate cancer; however, more studies are required to confirm the validation of this hypothesis.

ROS-driven supramolecular nanoparticles exhibiting efficient drug delivery for chemo/Chemodynamic combination therapy for Cancer treatment

Drug-based supramolecular self-assembling delivery systems have enhanced the bioavailability of chemotherapeutic drugs and reduced systemic side effects; however, improving the delivery efficiency and responsive release ability of these systems remains challenging. This study focuses primarily on the utilization of per-6-thio-β-cyclodextrin (CD) to link a significant quantity of paclitaxel (PTX) via ROS-sensitive thioketal (TK) linkages (designated as CDTP), thereby allowing efficiently drug release when exposed to high levels of reactive oxygen species (ROS) in the tumor microenvironment. To construct these supramolecular nanoparticles (NPs) with CDTP, we introduced PEGylated ferrocene (Fc) through host-guest interactions. The intracellular hydrogen peroxide (H2O2) is converted into hydroxyl radicals (•OH) through the Fc-catalyzed Fenton reaction. Additionally, the generated Fc+ consumes the antioxidant glutathione (GSH). In both in vivo and in vitro experiments, CDTP@Fc-PEG NPs were absorbed effectively by tumor cells, which increased levels of ROS and decreased levels of GSH, disrupting the redox balance of cancer cells and increasing their sensitivity to chemotherapy. Furthermore, CDTP@Fc-PEG NPs exhibited high tumor accumulation and cytotoxicity without causing significant toxicity to healthy organs. Collectively, our results suggest CDTP@Fc-PEG NPs as a promising supramolecular nano-delivery platform for high drug-loading of PTX and synergistic chemotherapy.

Effects of docetaxel on metastatic prostate (DU-145) carcinoma cells cultured as 2D monolayers and 3D multicellular tumor spheroids

Docetaxel (DTX) is one of the chemotherapeutic drugs indicated as a first-line treatment against metastatic prostate cancer (mPCa). This study aimed to compare the impact of DTX on mPCa (DU-145) tumor cells cultured as 2D monolayers and 3D multicellular tumor spheroids (MCTS) in vitro. The cells were treated with DTX (1-96 µM) at 24, 48, or 72 hr in cell viability assays (resazurin, phosphatase acid, and lactate dehydrogenase). Cell death was assessed with fluorescent markers and proliferation by clonogenic assay (2D) and morphology, volume, and integrity assay (3D). The cell invasion was determined using transwell (2D) and extracellular matrix (ECM) (3D). Results showed that DTX decreased cell viability in both culture models. In 2D, the IC50 (72 hr) values were 11.06 μM and 14.23 μM for resazurin and phosphatase assays, respectively. In MCTS, the IC50 values for the same assays were 114.9 μM and 163.7 μM, approximately 10-fold higher than in the 2D model. The % of viable cells decreased, while the apoptotic cell number was elevated compared to the control in 2D. In 3D spheroids, only DTX 24 μM induced apoptosis. DTX (≥24 μM at 216 hr) lowered the volume, and DTX 96 μM completely disintegrated the MCTS. DTX reduced the invasion of mPCa cells to matrigel (2D) and migration from MCTS to the ECM. Data demonstrated significant differences in drug response between 2D and 3D cell culture models using mPCa DU-145 tumor cells. MCTS resembles the early stages of solid tumors in vivo and needs to be considered in conjunction with 2D cultures when searching for new therapeutic targets.

Nanotherapeutics for prostate cancer treatment: A comprehensive review

Prostate cancer (PCa) is the most prevalent solid organ malignancy and seriously affects male health. The adverse effects of prostate cancer therapeutics can cause secondary damage to patients. Nanotherapeutics, which have special targeting abilities and controlled therapeutic release profiles, may serve as alternative agents for PCa treatment. At present, many nanotherapeutics have been developed to treat PCa and have shown better treatment effects in animals than traditional therapeutics. Although PCa nanotherapeutics are highly attractive, few successful cases have been reported in clinical practice. To help researchers design valuable nanotherapeutics for PCa treatment and avoid useless efforts, herein, we first reviewed the strategies and challenges involved in prostate cancer treatment. Subsequently, we presented a comprehensive review of nanotherapeutics for PCa treatment, including their targeting methods, controlled release strategies, therapeutic approaches and mechanisms. Finally, we proposed the future prospects of nanotherapeutics for PCa treatment.

Tumor Therapy Strategies Based on Microenvironment-Specific Responsive Nanomaterials

The tumor microenvironment (TME) is a complex and variable region characterized by hypoxia, low pH, high redox status, overexpression of enzymes, and high-adenosine triphosphate concentrations. In recent years, with the continuous in-depth study of nanomaterials, more and more TME-specific response nanomaterials are used for tumor treatment. However, the complexity of the TME causes different types of responses with various strategies and mechanisms of action. Aiming to systematically demonstrate the recent advances in research on TME-responsive nanomaterials, this work summarizes the characteristics of TME and outlines the strategies of different TME responses. Representative reaction types are illustrated and their merits and demerits are analyzed. Finally, forward-looking views on TME-response strategies for nanomaterials are presented. It is envisaged that such emerging strategies for the treatment of cancer are expected to exhibit dramatic trans-clinical capabilities, demonstrating the extensive potential for the diagnosis and therapy of cancer.

New insight in urological cancer therapy: From epithelial-mesenchymal transition (EMT) to application of nano-biomaterials

A high number of cancer-related deaths (up to 90) are due to metastasis and simple definition of metastasis is new colony formation of tumor cells in a secondary site. In tumor cells, epithelial-mesenchymal transition (EMT) stimulates metastasis and invasion, and it is a common characteristic of malignant tumors. Prostate cancer, bladder cancer and renal cancer are three main types of urological tumors that their malignant and aggressive behaviors are due to abnormal proliferation and metastasis. EMT has been well-documented as a mechanism for promoting invasion of tumor cells and in the current review, a special attention is directed towards understanding role of EMT in malignancy, metastasis and therapy response of urological cancers. The invasion and metastatic characteristics of urological tumors enhance due to EMT induction and this is essential for ensuring survival and ability in developing new colonies in neighboring and distant tissues and organs. When EMT induction occurs, malignant behavior of tumor cells enhances and their tend in developing therapy resistance especially chemoresistance promotes that is one of the underlying reasons for therapy failure and patient death. The lncRNAs, microRNAs, eIF5A2, Notch-4 and hypoxia are among common modulators of EMT mechanism in urological tumors. Moreover, anti-tumor compounds such as metformin can be utilized in suppressing malignancy of urological tumors. Besides, genes and epigenetic factors modulating EMT mechanism can be therapeutically targeted for interfering malignancy of urological tumors. Nanomaterials are new emerging agents in urological cancer therapy that they can improve potential of current therapeutics by their targeted delivery to tumor site. The important hallmarks of urological cancers including growth, invasion and angiogenesis can be suppressed by cargo-loaded nanomaterials. Moreover, nanomaterials can improve chemotherapy potential in urological cancer elimination and by providing phototherapy, they mediate synergistic tumor suppression. The clinical application depends on development of biocompatible nanomaterials.

Research Progress on Stimulus-Responsive Polymer Nanocarriers for Cancer Treatment

As drug carriers for cancer treatment, stimulus-responsive polymer nanomaterials are a major research focus. These nanocarriers respond to specific stimulus signals (e.g., pH, redox, hypoxia, enzymes, temperature, and light) to precisely control drug release, thereby improving drug uptake rates in cancer cells and reducing drug damage to normal cells. Therefore, we reviewed the research progress in the past 6 years and the mechanisms underpinning single and multiple stimulus-responsive polymer nanocarriers in tumour therapy. The advantages and disadvantages of various stimulus-responsive polymeric nanomaterials are summarised, and the future outlook is provided to provide a scientific and theoretical rationale for further research, development, and utilisation of stimulus-responsive nanocarriers.

The Role of Cyclodextrin in the Construction of Nanoplatforms: From Structure, Function and Application Perspectives

Cyclodextrins (CyDs) in nano drug delivery systems have received much attention in pursuit of good compatibility, negligible toxicity, and improved pharmacokinetics of drugs. Their unique internal cavity has widened the application of CyDs in drug delivery based on its advantages. Besides this, the polyhydroxy structure has further extended the functions of CyDs by inter- and intramolecular interactions and chemical modification. Furthermore, the versatile functions of the complex contribute to alteration of the physicochemical characteristics of the drugs, significant therapeutic promise, a stimulus-responsive switch, a self-assembly capability, and fiber formation. This review attempts to list recent interesting strategies regarding CyDs and discusses their roles in nanoplatforms, and may act as a guideline for developing novel nanoplatforms. Future perspectives on the construction of CyD-based nanoplatforms are also discussed at the end of this review, which may provide possible direction for the construction of more rational and cost-effective delivery vehicles.

Glutathione and Esterase Dual-Responsive Smart Nano-drug Delivery System Capable of Breaking the Redox Balance for Enhanced Tumor Therapy

Conventional chemotherapy usually fails to achieve its intended effect because of the poor water solubility, poor tumor selectivity, and low tumor accumulation of chemotherapy drugs. The systemic toxicity of chemotherapy agents is also a problem that cannot be ignored. It is expected that smart nano-drug delivery systems that are able to respond to tumor microenvironments will provide better therapeutic outcomes with decreased side effects of chemotherapeutics. Nano-drug delivery systems capable of breaking the redox balance can also increase the sensitivity of tumor cells to chemotherapeutics. In this study, using polymer-containing disulfide bonds, ester bonds, and d-α-tocopherol polyethylene glycol succinate (TPGS), which can amplify reactive oxygen species (ROS) in tumor cells, we have successfully prepared a smart glutathione (GSH) and esterase dual-responsive nano-drug delivery system (DTX@PAMBE-SS-TPGS NPs) with the ability to deplete GSH as well as amplify ROS and effectively release an encapsulated chemotherapy drug (DTX) in tumor cells. The potential of DTX@PAMBE-SS-TPGS NPs for enhanced antitumor effects was thoroughly evaluated using in vitro as well as in vivo experiments. Our research offers a promising strategy for maximizing the efficacy of tumor therapy.

A co-delivery system based on chlorin e6-loaded ROS-sensitive polymeric prodrug with self-amplified drug release to enhance the efficacy of combination therapy for breast tumor cells

Background: Recently, various combination therapies for tumors have garnered popularity because of their synergistic effects in improving therapeutic efficacy and reducing side effects. However, incomplete intracellular drug release and a single method of combining drugs are inadequate to achieve the desired therapeutic effect.

Methods: A reactive oxygen species (ROS)-sensitive co-delivery micelle (Ce6@PTP/DP). It was a photosensitizer and a ROS-sensitive paclitaxel (PTX) prodrug for synergistic chemo-photodynamic therapy. Micelles size and surface potential were measured. In vitro drug release, cytotoxicity and apoptosis were investigated.

Results: Ce6@PTP/DP prodrug micelles exhibited good colloidal stability and biocompatibility, high PTX and Ce6 loading contents of 21.7% and 7.38%, respectively. Upon light irradiation, Ce6@PTP/DP micelles endocytosed by tumor cells can generate sufficient ROS, not only leading to photodynamic therapy and the inhibition of tumor cell proliferation, but also triggering locoregional PTX release by cleaving the thioketal (TK) bridged bond between PTX and methoxyl poly (ethylene glycol). Furthermore, compared with single drug-loaded micelles, the light-triggered Ce6@PTP/DP micelles exhibited self-amplified drug release and significantly greater inhibition of HeLa cell growth.

Conclusion: The results support that PTX and Ce6 in Ce6@PTP/DP micelles exhibited synergistic effects on cell-growth inhibition. Thus, Ce6@PTP/DP micelles represent an alternative for realizing synergistic chemo-photodynamic therapy.

Effective Sonosensitizer Delivery by Redox Sensitive Nanoparticles for Prostate Cancer Sonodynamic Therapy via Amplifying Oxidative Stress and Peroxidation

Sonodynamic therapy (SDT), a novel noninvasive therapeutic modality, provides many noteworthy benefits by generating reactive oxygen species (ROS). However, water-insoluble sonosensitizer delivery strategies have continuously underperformed because of unavoidable toxicity and a short circulation time. In this study, l-cystine derivative-based biocompatible nanoparticles (NPs) that can be used in SDT and induce limited cytotoxicity are designed and synthesized. After ultrasonic (US) irradiation, these sonosensitizer-loaded NPs show highly efficient sonodynamic performance that leads to cytotoxic ROS production. The ability to stop and start ROS generation induced by US irradiation enables accurate temporal and spatial control. In vivo and in vitro experiments are systematically performed to investigate the effects of this system on tumors, and the results indicate remarkable tumor suppression via markedly high persistent oxidative stress that induces peroxidation and endoplasmic reticulum stress. Thus, this novel temporally and spatially controllable ROS generation platform offers a safe and effective theranostic strategy for prostate cancer treatment.

The Fabrication of Docetaxel-Containing Emulsion for Drug Release Kinetics and Lipid Peroxidation

Docetaxel (DTX)-based formulation development is still confronted with significant challenges, due to its refractory solubility and side effects on normal tissues. Inspired by the application of the transdermal drug delivery model to topical treatment, we developed a biocompatible and slow-release DTX-containing emulsion via self-assembly prepared by a high-speed electric stirring method and optimized the formulation. The results of accelerated the emulsion stability experiment showed that the emulsion prepared at 10,000 rpm/min had a stability of 89.15 ± 2.05%. The ADME, skin irritation, skin toxicity and molecular interaction between DTX and excipients were predicted via Discovery Studio 2016 software. In addition, DTX addition in oil or water phases of the emulsion showed different release rates in vitro and ex vivo. The DTX release ex vivo of the DTX/O-containing emulsion and the DTX/W-containing emulsion were 45.07 ± 5.41% and 96.48 ± 4.54%, respectively. In vitro antioxidant assays and anti-lipid peroxidation models revealed the antioxidant potential of DTX. However, DTX-containing emulsions could maintain and even enhance the antioxidant effect, both scavenging free radicals in vitro and inhibiting the process of lipid peroxidation.

Cyclodextrin-based supramolecular nanoparticles break the redox balance in chemodynamic therapy-enhanced chemotherapy

Drug delivery based on abnormal features of the tumor microenvironment (TME) has attracted considerable interest worldwide. In this study, we proposed an applicable strategy to increase the reactive oxygen species (ROS) and inhibit glutathione (GSH), in an effort to amplify oxidative damage in prostate cancer cells. Specifically, we developed dual-responsive supramolecular self-assembled nanoparticles (NPs) based on polymerized methacrylic acid (MA) and polymerized poly(ethylene glycol) dimethyl acrylate-modified β-cyclodextrin (CD) with ferrocene (Fc)-connected (S) (+)-camptothecin (CPT) (designated as MA-CD/Fc-CPT NPs). The as-prepared negatively charged supramolecular NPs can be taken up by tumor cells successfully owing to their reversible negative-to-positive charge transition capacity at acidic pH. The supramolecular NPs increased ROS generation and decreased GSH to amplify oxidative stress and improve the therapeutic effect of chemotherapy. As expected, MA-CD/Fc-CPT NPs displayed good drug delivery capabilities to tumor cells or tissues. MA-CD/Fc-CPT NPs also inhibited cancer cell proliferation in both the cells and tissues. This result was partially due to increased ROS generation and decreased GSH, which contributed to more pronounced oxidative stress. The as-prepared supramolecular NPs displayed great biosafety to normal tissues. According to our results, negatively charged supramolecular MA-CD/Fc-CPT NPs are well-suited for drug delivery and improved cancer treatment in TMEs.

H2O2-Responsive amphiphilic polymer with aggregation-induced emission (AIE) for DOX delivery and tumor therapy

Stimuli-responsive drug delivery systems (DDSs) based on amphiphilic polymers have attracted much attention. In this study, we reported an innovative H₂O₂-responsive amphiphilic polymer (TBP), bearing a H₂O₂-sensitive phenylboronic ester, AIE fluorophore tetraphenylethene (TPE) hydrophobic, and polyethylene glycol hydrophilic (PEG) moieties. TBP could self-assemble into micelles with an encapsulation efficiency as high as 74.9% for doxorubicin (DOX) in aqueous solution. In the presence of H₂O₂, TBP micelles was decomposed by oxidation, hydrolysis and rearrangement, leading to almost 80% DOX release from TBP@DOX micelles. TBP and the corresponding degradation products were biocompatible, while TBP@DOX micelles only displayed obvious toxicity toward cancer cells. Drug delivery process was clearly monitored by confocal laser scanning microscopic (CLSM) and flow cytometry (FCM) analysis. Moreover, in vivo anticancer study showed that TBP@DOX micelles were accumulated in tumor region of nude mice and effectively inhibited tumor growth. The results suggested that the reported H₂O₂-responsive amphiphilic polymer displayed great potential in drug delivery and tumor therapy.

Dual anticancer drug-loaded self-assembled nanomaterials delivery system for the treatment of prostate cancer

This study explains the engineering of polylactide-polyethylene succinate glycol nanomaterials (NMs), to achieve superior anticancer effectiveness in prostate cancer therapy as a carriers of crizotinib (CZT) and marizomib (MAR). We have shown that the block polymers and hydrophobic drugs can be self-assembled to construct a highly stable nanocarrier with highly adaptable to support the use of cancer medicines. The Drug Release analysis revealed that the interference in the hydrophobic cores of micelles was a continuous release series. In both PC3pip and LNCAP prostate cancer cells, CZT@MAR NMs demonstrated noticeable cytotoxic effects in a dose-responsive method. In addition, morphology analysis and the AO-EB and nuclear staining assay showed a higher effectiveness in prostate cancer for nanomaterials. The polymeric nanomaterials displayed a prominent existence in the cytoplasmic cell regions, which shows a characteristic cell uptake by endocytosis. A significant apoptosis, compared to free CZT@MAR apoptosis, was found in the FITC-Annexin V/PI staining-based apoptosis analysis. In this juncture, the alternative drug delivery mechanism for the improvement of CZT@MAR chemotherapeutic effectiveness in prostate cancer chemotherapy modification PLA nanoparticles.

Dextran-Curcumin Nanosystems Inhibit Cell Growth and Migration Regulating the Epithelial to Mesenchymal Transition in Prostate Cancer Cells

Functional nanocarriers which are able to simultaneously vectorize drugs to the site of interest and exert their own cytotoxic activity represent a significant breakthrough in the search for effective anticancer strategies with fewer side effects than conventional chemotherapeutics. Here, we propose previously developed, self-assembling dextran-curcumin nanoparticles for the treatment of prostate cancer in combination therapy with Doxorubicin (DOXO). Biological effectiveness was investigated by evaluating the cell viability in either cancer and normal cells, reactive oxygen species (ROS) production, apoptotic effect, interference with the cell cycle, and the ability to inhibit cell migration and reverse the epithelial to mesenchymal transition (EMT). The results proved a significant enhancement of curcumin efficiency upon immobilization in nanoparticles: IC50 reduced by a half, induction of apoptotic effect, and improved ROS production (from 67 to 134%) at low concentrations. Nanoparticles guaranteed a pH-dependent DOXO release, with a more efficient release in acidic environments. Finally, a synergistic effect between nanoparticles and Doxorubicin was demonstrated, with the free curcumin showing additive activity. Although in vivo studies are required to support the findings of this study, these preliminary in vitro data can be considered a proof of principle for the design of an effective therapy for prostate cancer treatment.