Cisplatin-loaded polymeric nanoparticles: characterization and potential exploitation for the treatment of non-small cell lung carcinoma

Platinum-based targeted chemotherapies and reversal of cisplatin resistance in non-small cell lung cancer (NSCLC)

Lung cancer is the one of the most prevalent cancer in the world. It kills more people from cancer than any other cause and is especially common in underdeveloped nations. With 1.2 million instances, it is also the most prevalent cancer in men worldwide, making about 16.7% of the total cancer burden. Surgery is the main form of curative treatment for early-stage lung cancer. However, the majority of patients had incurable advanced non-small cell lung cancer (NSCLC) recurrence after curative purpose surgery, which is indicative of the aggressiveness of the illness and the dismal outlook. The gold standard of treatment for NSCLC patients includes drug targeting of specific mutated genes drive in development of lung cancer. Furthermore, patients with advanced NSCLC and those with early-stage illness needing adjuvant therapy should use cisplatin as it is the more active platinum drug. So, this review encompasses the non-small cell lung cancer microenvironment, treatment approaches, and use of cisplatin as a first-line regimen for NSCLC, its mechanism of action, cisplatin resistance in NSCLC and also the prevention strategies to revert the drug resistance.

Investigations into the characterization, degradation, and applications of biodegradable polymers by mass spectrometry

Biodegradable polymers have been getting more and more attention because of their contribution to the plastic pollution environmental issues and to move towards a circular economy. Nevertheless, biodegradable materials still exhibit various disadvantages restraining a widespread use in the market. Therefore, additional research efforts are required to improve their performance. Mass spectrometry (MS) affords a relevant contribution to optimize biodegradable polymer synthesis, to confirm macromolecular structures, to examine along the time the progress of degradation processes and highlight advantages and drawbacks in the extensive applications. This review aims to provide an overview of the MS investigations carried out to support the synthesis of biodegradable polymers, with helpful information on undesirable products or polymerization mechanism, to understand deterioration pathways by the structure of degradation products and to follow drug release and pharmacokinetic. Additionally, it summarizes MS studies addressed on environmental and health issues related to the extensive use of plastic materials, that is, potential migration of additives or microplastics identification and quantification. The paper is focused on the most significant studies relating to synthetic and microbial biodegradable polymers published in the last 15 years, not including agro-polymers such as proteins and polysaccharides.

Polypeptide-Based Systems: From Synthesis to Application in Drug Delivery

Synthetic polypeptides are biocompatible and biodegradable macromolecules whose composition and architecture can vary over a wide range. Their unique ability to form secondary structures, as well as different pathways of modification and biofunctionalization due to the diversity of amino acids, provide variation in the physicochemical and biological properties of polypeptide-containing materials. In this review article, we summarize the advances in the synthesis of polypeptides and their copolymers and the application of these systems for drug delivery in the form of (nano)particles or hydrogels. The issues, such as the diversity of polypeptide-containing (nano)particle types, the methods for their preparation and drug loading, as well as the influence of physicochemical characteristics on stability, degradability, cellular uptake, cytotoxicity, hemolysis, and immunogenicity of polypeptide-containing nanoparticles and their drug formulations, are comprehensively discussed. Finally, recent advances in the development of certain drug nanoformulations for peptides, proteins, gene delivery, cancer therapy, and antimicrobial and anti-inflammatory systems are summarized.

Redox/pH-responsive hollow manganese dioxide nanoparticles for thyroid cancer treatment

The nano drug delivery system MnO2/CDDP@PDA-Cy5.5 was synthesized in this study to increase the efficacy of Cisplatin (CDDP) on thyroid cancer and alleviate the damage to normal tissue, with the aim of enhancing the anti-cancer efficacy, increasing the drug load, optimizing the control of drug release, and alleviating the systemic toxicity arising from drug off-target. On that basis, high efficacy and low toxicity win-win can be obtained. In this study, hollow manganese dioxide nanoparticles (MnO2 NPs) were prepared based on the template method. CDDP was loaded into the hollow cavity and then modified with polydopamine (PDA) and Cy5.5, with the aim of obtaining the nano-drug loading system MnO2/CDDP@PDA-Cy5.5 NPs. The NPs precisely delivered drugs by intelligently responding to the tumor microenvironment (TME). As indicated by the release curves, the NPs release CDDP rapidly by inducing the decomposition of PDA and MnO2 under acidic or redox conditions, and Magnetic resonance imaging (MRI) contrast agent Mn2+ was generated. The results of the in vivo MRI studies suggested that T1 contrast at the tumor site was notably enhanced under the Enhanced permeability and retention (EPR) effect. After the intravenous administration, the effective tumor accumulation exhibited by the NPs was confirmed by magnetic resonance imaging as a function of time. Compared with free CDDP, the in vivo therapeutic effect was remarkably increased. As indicated by the above-described results, MnO2/CDDP@PDA-Cy5.5 NPs is a drug delivery system exhibiting diagnostic and therapeutic functions.

Quantifying causal effects from observed data using quasi-intervention

BACKGROUND

Causal inference is a crucial element within medical decision-making. There have been many methods for investigating potential causal relationships between disease and treatment options developed in recent years, which can be categorized into two main types: observational studies and experimental studies. However, due to the nature of experimental studies, financial resources, human resources, and patients' ethical considerations, researchers cannot fully control the exposure of the research participants. Furthermore, most existing observational research designs are limited to determining causal relationships and cannot handle observational data, let alone determine the dosages needed for medical research.

RESULTS

This paper presents a new experimental strategy called quasi-intervention for quantifying the causal effect between disease and treatment options in observed data by using a causal inference method, which converts the potential effect of different treatment options on disease into computing differences in the conditional probability. We evaluated the accuracy of the quasi-intervention by quantifying the impact of adjusting Chinese patients' neutrophil-to-lymphocyte ratio (NLR) on their overall survival (OS) (169 lung cancer patients and 79 controls).The results agree with the literature in this study, consisting of nine papers on cohort studies on the NLR and the prognosis of lung cancer patients, proving that our method is correct.

CONCLUSION

Taken together, the results imply that quasi-intervention is a promising method for quantifying the causal effect between disease and treatment options without clinical trials, and it could improve confidence about treatment options' efficacy and safety.

Ameliorative impacts of polymeric and metallic nanoparticles on cisplatin-induced nephrotoxicity: a 2011-2022 review

Cisplatin (CDDP) is a well-known platinum-based drug used in the treatment of various malignancies. However, the widespread side effects that this drug leaves on normal tissues make its use limited. Since cisplatin is mainly eliminated from the kidneys, CDDP-induced nephrotoxicity is the most significant dose-limiting complication attributed to cisplatin, which often leads to dose withdrawal. Considering the high efficiency of cisplatin in chemotherapy, finding renoprotective drug delivery systems for this drug is a necessity. In this regard, we can take advantages of different nanoparticle-based approaches to deliver cisplatin into tumors either using passive targeting or using specific receptors. In an effort to find more effective cisplatin-based nano-drugs with less nephrotoxic effect, the current 2011-2022 review study was conducted to investigate some of the nanotechnology-based methods that have successfully been able to mitigate CDDP-induced nephrotoxicity. Accordingly, although cisplatin can cause renal failures through inducing mitochondria dysfunction, oxidative stress, lipid peroxidation and endoplasmic reticulum stress, some CDDP-based nano-carriers have been able to reverse a wide range of these advert effects. Based on the obtained results, it was found that the use of different metallic and polymeric nanoparticles can help renal cells to strengthen their antioxidant systems and stay alive through reducing CDDP-induced ROS generation, inhibiting apoptosis-related pathways and maintaining the integrity of the mitochondrial membrane. For example, nanocurcumin could inhibit oxidative stress and acting as a ROS scavenger. CONPs could reduce lipid peroxidation and pro-inflammatory cytokines. CDDP-loaded silver nanoparticles (AgNPs) could inhibit mitochondria-mediated apoptosis. In addition, tea polyphenol-functionalized SeNPs (Se@TE) NPs could mitigate the increased level of dephosphorylated AKT, phosphorylated p38 MAPK and phosphorylated c-Jun N-terminal kinase (JNK) induced by cisplatin. Moreover, exosomes mitigated cisplatin-induced renal damage through inhibiting Bcl2 and increasing Bim, Bid, Bax, cleaved caspase-9, and cleaved caspase-3. Hence, nanoparticle-based techniques are promising drug delivery systems for cisplatin so that some of them, such as lipoplatins and nanocurcumins, have even reached phases 1-3 trials.

Cisplatin Nanoparticles Promote Intratumoral CD8+ T Cell Priming via Antigen Presentation and T Cell Receptor Crosstalk

Nanomedicines are highly promising for cancer therapy due to their minimal side effects. However, little is known regarding their host immune response, which may limit their clinical efficacy and applications. Here, we find that cisplatin (CDDP)-loaded poly(l-glutamic acid)-graft-methoxy poly(ethylene glycol) complex nanoparticles (CDDP-NPs) elicit a strong antitumor CD8⁺ T cell-mediated immune response in a tumor-bearing mouse model compared to free CDDP. Mechanistically, the sustained retention of CDDP-NPs results in persistent tumor MHC-I overexpression, which promotes the formation of MHC-I-antigen peptide complex (pMHC-I), enhances the interaction between pMHC-I and T cell receptor (TCR), and leads to the activation of TCR signaling pathway and CD8⁺ T cell-mediated immune response. Furthermore, CDDP-NPs upregulate the costimulatory OX40 on intratumoral CD8⁺ T cells, and synergize with the agonistic OX40 antibody (aOX40) to suppress tumor growth by 89.2%. Our study provides a basis for the efficacy advantage of CDDP-based nanomedicines and immunotherapy.

Platinum Nanoparticles in Biomedicine: Preparation, Anti-Cancer Activity, and Drug Delivery Vehicles

Cancer is the main cause of morbidity and mortality worldwide, excluding infectious disease. Because of their lack of specificity in chemotherapy agents are used for cancer treatment, these agents have severe systemic side effects, and gradually lose their therapeutic effects because most cancers become multidrug resistant. Platinum nanoparticles (PtNPs) are relatively new agents that are being tested in cancer therapy. This review covers the various methods for the preparation and physicochemical characterization of PtNPs. PtNPs have been shown to possess some intrinsic anticancer activity, probably due to their antioxidant action, which slows tumor growth. Targeting ligands can be attached to functionalized metal PtNPs to improve their tumor targeting ability. PtNPs-based therapeutic systems can enable the controlled release of drugs, to improve the efficiency and reduce the side effects of cancer therapy. Pt-based materials play a key role in clinical research. Thus, the diagnostic and medical industries are exploring the possibility of using PtNPs as a next-generation anticancer therapeutic agent. Although, biologically prepared nanomaterials exhibit high efficacy with low concentrations, several factors still need to be considered for clinical use of PtNPs such as the source of raw materials, stability, solubility, the method of production, biodistribution, accumulation, controlled release, cell-specific targeting, and toxicological issues to human beings. The development of PtNPs as an anticancer agent is one of the most valuable approaches for cancer treatment. The future of PtNPs in biomedical applications holds great promise, especially in the area of disease diagnosis, early detection, cellular and deep tissue imaging, drug/gene delivery, as well as multifunctional therapeutics.

Lipid, polymeric, inorganic-based drug delivery applications for platinum-based anticancer drugs

The three main FDA-approved platinum drugs in chemotherapy such as carboplatin, cisplatin, and oxaliplatin are extensively applied in cancer treatments. Although the clinical applications of platinum-based drugs are extremely effective, their toxicity profile restricts their extensive application. Therefore, recent studies focus on developing new platinum drug formulations, expanding the therapeutic aspect. In this sense, recent advances in the development of novel drug delivery carriers will help with the increase of drug stability and biodisponibility, concomitantly with the reduction of drug efflux and undesirable secondary toxic effects of platinum compounds. The present review describes the state of the art of platinum drugs with their biological effects, pre- and clinical studies, and novel drug delivery nanodevices based on lipids, polymers, and inorganic.

Polypeptides-Drug Conjugates for Anticancer Therapy

Polypeptides are an important class of biodegradable polymers that have been widely used in drug delivery field. Owing to the controllable synthesis and robust side chain-functionalization ability, polypeptides have long been ideal candidates for conjugation with anticancer drugs. The chemical conjugation of anticancer drugs with polypeptides, termed polypeptides-drug conjugates, has demonstrated several advantages in improving pharmacokinetics, enhancing drug targeting, and controlling drug release, thereby leading to enhanced therapeutic outcomes with reduced side toxicities. This review focuses on the recent advances in the design and preparation of polypeptides-drug conjugates for enhanced anticancer therapy. Strategies for conjugation of different types of drugs, including small-molecule chemotherapeutic drugs, proteins, vascular disrupting agents, and gas molecules, onto polypeptides backbone are summarized. Finally, the challenges and future perspectives on the development of innovative polypeptides-drug conjugates for clinical cancer treatment are also presented.

Cisplatin Loaded Poly(L-glutamic acid)-g-Methoxy Polyethylene Glycol Complex Nanoparticles Combined with Gemcitabine Presents Improved Safety and Lasting Anti-Tumor Efficacy in a Murine Xenograft Model of Human Aggressive B Cell Lymphoma

Cisplatin (CDDP) is a highly effective anti-tumor drug with a broad spectrum of activity. However, the clinical efficacy of CDDP-containing regimens is yet unsatisfactory due to the severe dose-related toxicity of CDDP. In a previous study, CDDP nanoparticles (L-CDDP) forms a complex as CDDP with poly(L-glutamic acid)-g-methoxy poly(ethylene glycol) with improved safety compared to CDDP. Herein, a murine xenograft model of human aggressive B cell lymphoma (BCL) was established to explore anti-lymphoma efficiency of L-CDDP combined with GEM. BJAB cells represent an aggressive BCL, which were utilized to explore the anti-proliferative effect, cell apoptosis via CCK-8 test and flow cytometry technology, respectively. Toxicity experiment and the maximum tolerated dose (MTD) test were conducted in Kunming mice. Tumor inhibition experiment was conducted at the dose of MTD in SCID beige mice-bearing lymphoma. In this study, the loading capacity and encapsulating efficiency of CDDP in the L-CDDP was 18.3% and 89.7%, respectively, and the hydrodynamic diameter of the prepared L-CDDP was 20.6 nm. The CCK-8 data indicated that the anti-proliferative activity of monodrug groups (GEM, CDDP, L-CDDP) was dose- and time-dependent in BJAB cells. The synergistic effects in anti-lymphoma were detected in these two groups (GEM+CDDP, GEM + L-CDDP). Compared to control group, the proportion of apoptotic cells in experimental groups in BJAB cells was significantly higher at 48 h. Toxicity assays revealed that GEM + L-CDDP regimen had low hematological toxicity, hepatotoxicity, and nephrotoxicity. Tumor inhibition experiment demonstrated that GEM + L-CDDP group exhibited significant tumor-suppressing effects. Moreover, tumors continued to shrink in GEM + L-CDDP group, while these appeared to grow in the GEM + CDDP group. Finally, tumor necrosis was most prominent in the GEM + CDDP and GEM + L-CDDP groups, as assessed by hematoxylin-eosin staining. In conclusion, compared to CDDP, L-CDDP combined with GEM seriously induces BJAB cell apoptosis. Also, GEM + L-CDDP exhibits low hematotoxicity, hepatotoxicity, and nephrotoxicity. Importantly, GEM + L-CDDP presents lasting anti-lymphoma efficacy in a SCID beige mice-bearing lymphoma.

Poly(L-Glutamic Acid)-Drug Conjugates for Chemo- and Photodynamic Combination Therapy

Despite the polymeric vascular disrupting agent (poly(_L -glutamic acid)-graft-methoxy poly(ethylene glycol)/combretastatin A4) nanoparticles can efficiently inhibit cancer growth, their further application is still a challenge owing to the tumor recurrence and metastasis after treatment. In this study, two poly(_L -glutamic acid)-drug conjugates for chemo-and photodynamic combination therapy are fabricated. PLG-g-mPEG-CA4 nanoparticles are prepared by combretastatin A4 (CA4) and poly(_L -glutamic acid)-graft-methoxy poly(ethylene glycol) (PLG-g-mPEG) using the Yamaguchi esterification reaction. PLG-g-mPEG-TPP (TPP: 5, 10, 15, 20-tetraphenylporphyrin) nanoparticles are constructed using PLG-g-mPEG and amine porphyrin through condensation reaction between carboxyl group of PLG-g-mPEG and amino group of porphyrin. The results showed that PLG-g-mPEG-CA4 nanoparticles have good antitumor ability. PLG-g-mPEG-TPP nanoparticles can produce singlet oxygen under the laser irradiation. Moreover, the combined therapy of PLG-g-mPEG-CA4 and PLG-g-mPEG-TPP nanoparticles has higher antitumor effect than the single chemotherapy or the single photodynamic therapy in vitro. The combination of CA4 nondrug and photodynamic therapy provides a new insight for enhancing the tumor therapeutic effect with vascular disrupting agents and other therapy.

An immune cocktail therapy to realize multiple boosting of the cancer-immunity cycle by combination of drug/gene delivery nanoparticles

Immune checkpoint blockade therapy (ICT) has shown potential in the treatment of multiple tumors, but suffers poor response rate in clinic. We found that even combining ICT with chemotherapy, which was wildly used in clinical trials, failed to achieve satisfactory tumor inhibition in the B16F10 model. Thus, we further constructed a previously unexplored immune cocktail therapy and realized multiple boosting of the cancer-immunity cycle. Cocktail therapy consisted of two kinds of tumor microenvironment-responsive drug and gene delivery nanoparticles to achieve specific delivery of doxorubicin and codelivery of plasmids expressed small hairpin RNA of PD-L1 (pshPD-L1) and hyaluronidase (pSpam1) in the tumor area. Experimental evidences proved that any component in the cocktail therapy was indispensable, and the cocktail therapy exhibited excellent antitumor effects against different types of tumors. The cocktail therapy presented here offers a searching strategy for more synergistic units with ICT and is meaningful for developing more efficient antitumor immunotherapy.

Recent advances in metallopolymer-based drug delivery systems

Metallopolymers (MPs) or metal-containing polymers have shown great potential as new drug delivery systems (DDSs) due to their unique properties, including universal architectures, composition, properties and surface chemistry. Over the past few decades, the exponential growth of many new classes of MPs that deal with these issues has been demonstrated. This review presents and assesses the recent advances and challenges associated with using MPs as DDSs. Among the most widely used MPs for these purposes, metal complexes based on synthetic and natural polymers, coordination polymers, metal-organic frameworks, and metallodendrimers are distinguished. Particular attention is paid to the stimulus- and multistimuli-responsive metallopolymer-based DDSs. Of considerable interest is the use of MPs for combination therapy and multimodal systems. Finally, the problems and future prospects of using metallopolymer-based DDSs are outlined. The bibliography includes articles published over the past five years.

Diplatin, a Novel and Low-Toxicity Anti-Lung Cancer Platinum Complex, Activation of Cell Death in Tumors via a ROS/JNK/p53-Dependent Pathway, and a Low Rate of Acquired Treatment Resistance

Background: Platinum-based drugs prevail as the main treatment of lung cancer; this is caused by their relative effectiveness despite known side effects, such as neurotoxicity. The risk reward of the treatment and side effects is confronted when dosage is considered and when resistance to treatment develops. Development of new compounds that improve effectiveness and safety profiles addresses this ongoing need in clinical practice.

Objectives: The novel water-soluble platinum complex, diplatin, was synthesized, and its antitumor potency and toxicology profile were evaluated in murine xenograft tumor models and in lung cancer cell lines.

Methods: The effects of diplatin, cisplatin (DDP), and carboplatin (CBP) on the viability of nine lung tumor cell lines and one normal human lung epithelial cell line were evaluated using the MTT assay. Therapeutic index was calculated as LD₅₀/ED₅₀ to identify and compare the ideal therapeutic windows of the above compounds. Diplatin’s antitumor effects were assessed in lung xenograft tumors of nude mice; molecular mechanisms of therapeutic effects were identified.

Results: Diplatin had desirable IC₅₀ compared to CBP in a variety of cultured tumor cells, notably lung tumor cells. In the mouse xenograft lung tumor, diplatin led to a substantially improved therapeutic index when compared to the effects of DDP and CBP. Importantly, diplatin inhibited the growth of DDP-resistant lung tumor cells. Diplatin’s mode of action was characterized to be through cell cycle arrest in the G2/M phase and induction of lung tumor apoptosis via ROS/JNK/p53-mediated pathways.

Conclusion: Diplatin was observed to have antitumor effects in mice with both greater potency and safety compared with DDP and CBP. These observations indicate that diplatin is promising as a potential treatment in future clinical applications.

Recent progress in nanotechnology-based novel drug delivery systems in designing of cisplatin for cancer therapy: an overview

Cisplatin cis-(diammine)dichloridoplatinum(II) (CDDP) is the first platinum-based complex approved by the food and drug administration (FDA) of the United States (US). Cisplatin is the first line chemotherapeutic agent used alone or combined with radiations or other anti-cancer agents for a broad range of cancers such as lung, head and neck. Aroplatin™, Lipoplatin™ and SPI-077 are PEGylated liposome-based nano-formulations that are still under clinical trials. They have many limitations, for example, poor aqueous solubility, drug resistance and toxicities, which can be overcome by encapsulating the cisplatin in Nemours nanocarriers. The extensive literature from different electronic databases covers the different nano-delivery systems that are developed for cisplatin. This review critically emphasizes on the recent advancement, development, innovations and updated literature reported for different carrier systems for CDDP.

Cisplatin-loaded polymeric complex micelles with a modulated drug/copolymer ratio for improved in vivo performance

This study aimed to evaluate the performance of cisplatin-loaded polymeric micelles (CDDP-PMs) with different drug/copolymer ratios of 1:1, 1:3 and 1:6 (w/w) prepared by coordinated complexation and self-assembly method. The mass ratio influenced the self-assembly behaviors and the complex degree, where both single- and double- complexation existed in CDDP-PMs. With the increase of CDDP/copolymer ratio, the particle size and drug loading increased, while encapsulation efficiency decreased. The PEG density of CDDP-PM_1-6, CDDP-PM_1-3 and CDDP-PM_1-1 were 0.20, 0.61 and 0.38 PEG/nm², respectively. CDDP-PM_1-3 and CDDP-PM_1-6 had similar sustained release behavior, while CDDP-PM_1-1 showed burst release. Pharmacokinetics showed the AUC of CDDP-PM_1-6, CDDP-PM_1-3 and CDDP-PM_1-1 was 27.2, 76.6 and 13.0 fold higher than CDDP solution. Tissue distribution presented the platinum concentration of CDDP-PM_1-6, CDDP-PM_1-3 and CDDP-PM_1-1 was 1.03, 0.80 and 0.48 times of CDDP solution in kidney at 10 min, and 17.61, 28.63 and 16.6 times in tumor at 48 h respectively, indicating CDDP-PMs significantly reduced nephrotoxicity and increased tumor-targeting accumulation. In vivo antitumor test showed that CDDP-PMs exhibited an improved antitumor efficacy and lower systemic toxicity compared with CDDP solution. From CDDP-PM_1-1 to CDDP-PM_1-6, the toxicity decreased with the increase of copolymer ratio, but the tumor inhibition rate also decreased. CDDP-PM_1-3 had relative high therapeutic effect and low toxicity compared with other formulations. CDDP-PM_1-3 could improve the antitumor efficacy by increasing the dose within systemic tolerability, but CDDP solution cannot. This work provides an effective strategy by modulating drug/copolymer ratio of CDDP-PMs to balance the antitumor efficacy and toxicity for better payoff. STATEMENT OF SIGNIFICANCE: Cancer chemotherapy always exists a contradiction between antitumor efficacy and toxicity. Higher efficacy against tumor often associated with larger toxicity for normal tissues. This work provides an important strategy by modulating the drug/copolymer ratios to balance the antitumor efficacy and toxicity to obtain better payoff. The cisplatin-loaded polymeric micelles (CDDP-PMs) based on the complexation between CDDP and copolymer with different mass ratios make differences in vitro and in vivo because of the single- or double-complexation degree. Most importantly, we found the balance at CDDP/copolymer ratio of 1:3, which has relative high therapeutic effect and low toxicity compared with other formulations. CDDP-PM_1-3 could improve the antitumor efficacy by increasing the dose within systemic tolerability, but CDDP solution cannot.

Gold nanoparticle-assisted enhancement in the anti-cancer properties of theaflavin against human ovarian cancer cells

Redox-active quinones have been reported to show good potential for biological activities, while efforts are directed to explore the usefulness of these materials further in cancer management. Our previous study demonstrated that theaflavin and theaflavin-gallates (tea-extracted polyphenols) selectively induce apoptosis of tumour cells in vitro, but its concentration for showing half-maximal therapeutic response remains a matter of concern. In this report, we demonstrated that if theaflavin is conjugated with gold nanoparticles (AuNPs) to form a nanoconjugate AuNP@TfQ, its apoptotic ability increases significantly in comparison to the bare theaflavin (Tf). The nanoconjugate is prepared by following a one-step green synthesis ̶ a reaction between HAuCl₄ and the aflavin at room temperature. AuNP@TfQ is characterized using particle size analysis, FESEM, UV-vis, FTIR, fluorescence, and X-ray photoelectron spectroscopytechniques. We assume that the enhanced anti-cancer effect of AuNP@TfQ appears due to the facile oxidation of the pristine theaflavin to its quinone derivative on the surface of AuNPs. The presence of quinone motif in AuNP@TfQ induces an increased level of ROS generation probably through the depolarization of mitochondria and resulted in the caspase-mediated apoptotic cell death which may hold the potential for a "magic bullet"-mediated ovarian cancer treatment.

pH responsible and fluorescent Cy5.5-PEG-g-A-HA/CDDP complex nanoparticles: synthesis, characterization, and application for targeted drug delivery

Clinical application of cisplatin (CDDP) against various solid tumors is often limited due to its poor selectivity and severe side effect. Considering this, in our study, CDDP was incorporated in fluorescent PEG amine grafted aldehyde hyaluronic acid by imine bond and metal ion coordination bond linking and formed a complex, the complex was then self-assembled into nanoparticles in water simply. FT-IR, XRD, DLS and SEM analysis demonstrated that the nanoparticles were prepared successfully and exhibited a spherical structure with size ranged from 216.4 to 372.3 nm in diameter. CDDP releasing from the nanoparticles was in a controlled manner, and had faster release rate at lower pH, indicating the nanoparticles were responsive to tumor micro-acid environment. Since fluorescent Cy5.5 and targeting hyaluronic acid existed on the surface of the nanoparticles, CLSM images clearly showed that the nanoparticles could target and internalize into HeLa cells, and then inhibited the growth of HeLa cells. In addition, MTT, AO-EB staining, and hemolysis assay showed that the nanoparticles had good cyto-/hemo-compatibility. Hence, the nanoparticles had the potential to be used for cancer therapy and diagnosis. The further in vivo experiment will be shown in the next work. pH responsible and fluorescent Cy5.5-PEG-g-A-HA/CDDP complex nanoparticles were facilely fabricated for controlled and targeted delivery of CDDP.

Reducing the toxicity of amphotericin B by encapsulation using methoxy poly(ethylene glycol)-b-poly(l-glutamic acid-co-l-phenylalanine)

Amphotericin B (AmB) is an antifungal drug used for serious fungal infections and leishmaniosis. However, its clinical application is limited because of its high toxicity. To resolve this problem, herein we loaded AmB into methoxy poly(ethylene glycol)-b-poly(l-glutamic acid-co-l-phenylalanine) (mPEG-b-P(Glu-co-Phe)) nanoparticles (l-AmB) via electrostatic, hydrophobic and π-π interactions. The l-AmB has excellent stability both in PBS and in plasma and shows a remarkably reduced hemolysis (17.1 ± 1.5%, 6 h) compared to the free AmB (94.2 ± 5.3%, 6 h). The nephrotoxicity of l-AmB is significantly lower than that of free AmB. The maximum tolerance dose (MTD) of l-AmB is 3.0 mg kg-1, which is 3.75 fold that of free AmB (MTD = 0.8 mg kg-1). The antimicrobial activity of the conjugate was retained in vivo, with l-AmB proving to be a more protective treatment for Aspergillus fumigatus infections in mice than AmB alone. These indicate that l-AmB is a formulation of AmB with low side effects.

Synthesis of multifunctional Fe3O4@PLGA-PEG nano-niosomes as a targeting carrier for treatment of cervical cancer

A new folic acid (FA)-conjugated poly (lactic-co-glycolicacid) (PLGA)-polyethylene glycol (PEG) nano-noisome was prepared. The noisome was employed as a drug delivery system to load curcumin (Cur) as a model drug and fluorescent probe for cervical cancer therapy and cell imaging. The Fe₃O₄@PLGA-PEG@FA noisomes were prepared through facile emulsion solvent evaporation and conjugation chemistry method, possessing the properties of high rapid magnetic separation and targeting character. X-ray photoelectron spectroscopy (XRD), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), thermogravimetric analysis (TGA), and vibrating sample magnetometer (VSM) were adopted to characterize the chemical structure and properties of these niosomes. MTT assay revealed that the blank noisomes exhibited excellent biocompatibility. The in vitro drug loading and release behavior studier showed the as prepared nano-noisome presented ultrahigh performance as drug carrier. The confocal laser scanning microscopy (CLSM) and flow cytometry (FCM) experiments demonstrated that Cur-loaded Fe₃O₄@PLGA-PEG@FA niosomes achieved significantly high targeting efficiency for cervical cancer. Additionally, the FA-targeted niosomes exhibited higher antitumor efficiency than free Cur. Cell morphology, the mitochondrial membrane potential and cell cycle changes indicated that Cur-loaded niosomes induced HeLa229 cells to apoptosis by destroying mitochondrion of cervical tumor cells, simultaneously changing nuclear morphology and blocking tumor cell proliferation. These results demonstrate that Fe₃O₄@PLGA-PEG@FA noisomes have promising applications as targeted drug delivery system for sustained drug release in cancer treatment.

Poly (l-glutamic acid)-g-methoxy poly (ethylene glycol)-gemcitabine conjugate improves the anticancer efficacy of gemcitabine

Gemcitabine is widely used for anticancer therapy. However, its short blood circulation time and poor stability greatly impair its application. To solve this problem, we prepared a poly (l-glutamic acid)-g-methoxy poly (ethylene glycol)-gemcitabine conjugate (l-Gem) with a 14.3 wt% drug-loading content. l-Gem showed concentration- and time-dependent cytotoxicity towards 4T1, LLC, MIA PaCa-2 and A2780 in vitro. Pharmacokinetic and biodistribution studies indicated that l-Gem had remarkably enhanced blood stability, prolonged blood circulation time and greatly improved selective tumor distribution compared with free gemcitabine. The area under the concentration-time curve from zero to infinity [AUC_(0-∞)] of l-Gem in plasma was 43-fold higher than that of free gemcitabine. The AUC_(0-∞) of the inactive metabolite, 2'-deoxy-2',2'-difluorouridine in the l-Gem group was ∼20% of that observed in the free gemcitabine group. The drug tumor accumulation ratio in the l-Gem group relative to the free gemcitabine group was 9.9 at 36 h, while the tumor AUC ratio was 15.8. Testing on Balb/C mice bearing the 4T1 tumor further demonstrated that l-Gem had significantly higher anticancer efficacy than free gemcitabine in vivo. These findings indicated that l-Gem has great potential for cancer treatment.

PEGylated self-assembled enzyme-responsive nanoparticles for effective targeted therapy against lung tumors

Background

Matrix-metalloproteinases, which are overexpressed in many types of cancer, can be applied to improve the bioavailability of chemotherapeutic drugs and guide therapeutic targeting. Thus, we aimed to develop enzyme-responsive nanoparticles based on a functionalized copolymer (mPEG-Peptide-PCL), which was sensitive to matrix metalloproteinase, as smart drug vesicles for enhanced biological specificity and reduced side effects.

Results

The rate of in vitro curcumin (Cur) release from Cur-P-NPs was not markedly accelerated in weakly acidic tumor microenvironment, indicating a stable intracellular concentration and a consistent therapeutic effect. Meanwhile, P-NPs and Cur-P-NPs displayed prominent biocompatibility, biostability, and inhibition efficiency in tumor cells. In addition, Cur-P-NPs showed higher fluorescence intensity than Cur-NPs in tumor cells, implying enhanced cell permeability and targeting ability. Moreover, the internalization and intracellular transport of Cur-P-NPs were mainly via macropinocytosis. Studies of pharmacodynamics and cellular uptake in vitro and biodistribution in vivo demonstrated that Cur-P-NPs had stronger target efficiency and therapeutic effect than Cur-DMSO and Cur-NPs in tumor tissue.

Conclusion

Results indicate that Cur-P-NPs can be employed for active targeted drug delivery in cancer treatment and other biomedical applications.

Electronic supplementary material

The online version of this article (10.1186/s12951-018-0384-8) contains supplementary material, which is available to authorized users.

Layer-by-layer nanoparticles co-loading gemcitabine and platinum (IV) prodrugs for synergistic combination therapy of lung cancer

Purpose

Cisplatin plus gemcitabine (GEM) is a standard regimen for the first-line treatment of advanced non-small cell lung cancer. The aim of this study was to prepare biocompatible and biodegradable polymeric prodrugs and construct nanoparticles (NPs) with layer-by-layer (LbL) technique.

Methods

Platinum (Pt) (IV) complex with a carboxyl group was conjugated to the amino group of chitosan (CH), resulting in a CH-Pt conjugation with positive charge. GEM with amino group was conjugated to the carboxyl group of hyaluronic acid (HA), resulting in a HA-GEM conjugation with negative charge. Novel LbL NPs consisting of the CH-Pt core and the HA-GEM layer, named as HA-GEM/CH-Pt NPs, were constructed. The physicochemical properties of the HA-GEM/CH-Pt NPs were investigated. In vitro cytotoxicity against human non-small lung cancer cells (NCl-H460 cells) was investigated, and in vivo antitumor efficiency was evaluated on mice bearing NCl-H460 cells xenografts.

Results

HA-GEM/CH-Pt NPs have a size of about 187 nm, a zeta potential value of −21 mV and high drug encapsulation efficiency of 90%. The drug release of HA-GEM/CH-Pt NPs exhibited a sustained behavior. HA-GEM/CH-Pt NPs could significantly enhance in vitro cytotoxicity and in vivo antitumor effect against lung cancer animal model compared to the single-drug-loaded NPs and free drug solutions.

Conclusion

The results demonstrated that the HA-GEM/CH-Pt NPs might be a promising system for the synergetic treatment of lung carcinoma.

A poly(l-glutamic acid)-combretastatin A4 conjugate for solid tumor therapy: Markedly improved therapeutic efficiency through its low tissue penetration in solid tumor

Combretastatin A4 (CA4) is a leading agent in vascular disrupting strategies for tumor therapy. Although many small-molecule prodrugs of CA4 have been developed to improve its solubility, the overall therapeutic efficiency is moderate. A key reason for this is the reversible effect that CA4 has on tubulin as well as its rapid clearance from plasma and tissues. In this study, we proposed a poly(l-glutamic acid)-CA4 conjugate (PLG-CA4) nanomedicine to fulfill the requirements for fully liberating the potential of CA4 on tumor therapy. Enhanced accumulation and retention of CA4 in tumor tissue, especially, high distribution and gradual release around tumor blood vessels resulted in prolonged vascular disruption and markedly enhanced therapeutic efficiency. We examined and compared the therapeutic effect of PLG-CA4 and commercial combretastatin-A4 phosphate (CA4P) in a murine colon C26 tumor. PLG-CA4 showed significantly prolonged retention in plasma and tumor tissue. Most importantly, the PLG-CA4 was mainly distributed around the tumor vessels because of its low tissue penetration in solid tumor. Pathology tests showed that PLG-CA4 treatment resulted in persistent vascular disruption and tumor damage 72h after a single injection, this in contrast to CA4P treatment, which showed quick relapse at an equal dose. Tumor suppression tests showed that PLG-CA4 treatment resulted in a tumor suppression rate of 74%, which indicates a significant advantage when compared to tumor suppression rate of the CA4P group, which was 24%. This is the first time that an advantage of the polymeric CA4 nanomedicine with low tissue penetration for solid tumor therapy has been shown. Thus, the results presented in this study provide a new idea for enhancing the tumor therapeutic effect of vascular disrupting agents.

STATEMENT OF SIGNIFICANCE

Nanomedicine usually has low tissue penetration in solid tumors, which limits the efficacy of nanomedicine in most cases. But herein, we demonstrate a nanosized vascular disruptive agent (VDA) PLG-CA4 has supper advantages over small molecular combretastatin-A4 phosphate (CA4P) because the PLG-CA4 was mainly distributed around the tumor vessels due to its low tissue penetration in solid tumor.

Targeted glioma chemotherapy by cyclic RGD peptide-functionalized reversibly core-crosslinked multifunctional poly(ethylene glycol)-b-poly(ε-caprolactone) micelles

Cyclic RGD peptide-functionalized reversibly core-crosslinked biodegradable poly(ethylene glycol)-b-poly(ε-caprolactone) (PEG-PCL) micelles (cRGD-RCCMs) were designed and developed for highly potent and targeted glioma chemotherapy. To achieve crosslinkable core, dithiolane-functionalized trimethylene carbonate (DTC) was incorporated into PCL block. Interestingly, cRGD-RCCMs displayed a high doxorubicin (DOX) loading content of ∼18wt%, small hydrodynamic size of ∼50nm, and excellent colloidal stability with minimum drug leakage under physiological conditions while fast DOX release under cytoplasmic-mimicking reductive environments. MTT, confocal microscopy and flow cytometry measurement results pointed out that cRGD-RCCMs with 30% cRGD surface density (cRGD30-RCCMs) showed an evident selectivity, efficient cytoplasmic drug release, and superior antitumor activity to clinically used pegylated liposomal doxorubicin (DOX-LPs) in α_vβ₃ integrin overexpressing U87MG glioblastoma cells. Strikingly, DOX-loaded cRGD30-RCCMs demonstrated a prolonged circulation time showing an elimination half-life of ∼4.7h, three times exceeding that of the non-crosslinked counterparts, and a remarkably enhanced tumor accumulation of 7.7%ID/g. Furthermore, in vivo therapeutic studies revealed that DOX-loaded cRGD30-RCCMs effectively suppressed tumor growth, significantly prolonged survival time, and lessened side effects in subcutaneous U87MG glioblastoma-bearing nude mice. These reversibly core-crosslinked multifunctional biodegradable micelles might be developed into advanced and clinically viable targeted anticancer nanomedicines.

STATEMENT OF SIGNIFICANCE

Nanomedicines based on biodegradable micelles and nanoparticles offer a most promising treatment for malignant tumors. The therapeutic outcomes of current nanomedicines are, however, trimmed by their instability, low tumor retention, inefficient tumor cell uptake, and inferior drug release control. We report herein that cRGD-functionalized, rapidly glutathione-responsive, and reversibly core-crosslinked biodegradable micellar doxorubicin based on PEG-PCL block copolymer mediates potent and targeted glioma chemotherapy, affording significantly better treatment efficacy and lower systemic toxicity than the non-crosslinked micellar doxorubicin and clinically used pegylated liposomal doxorubicin controls. These reversibly core-crosslinked multifunctional biodegradable micelles have emerged as a robust, simple, versatile, and safe nanoplatform that might elegantly bridge the gap between the scientific and translational anticancer nanomedicine research.

Novel nanoparticulate systems for lung cancer therapy: an updated review

Lung cancer is the leading cause of cancer-related deaths in the world. Conventional therapy for lung cancer is associated with lack of specificity and access to the normal cells resulting in cytotoxicity, reduced cellular uptake, drug resistance and rapid drug clearance from the body. The emergence of nanotechnology has revolutionized the treatment of lung cancer. The focus of nanotechnology is to target tumor cells with improved bioavailability and reduced toxicity. In the recent years, nanoparticulate systems have extensively been exploited in order to overcome the obstacles in treatment of lung cancer. Nanoparticulate systems have shown much potential for lung cancer therapy by gaining selective access to the tumor cells due to surface modifiability and smaller size. In this review, various novel nanoparticles (NPs) based formulations have been discussed in the treatment of lung cancer. Nanotechnology is expected to grow fast in future, and it will provide new avenues for the improved treatment of lung cancer. This review article also highlights the characteristics, recent advances in the designing of NPs and therapeutic outcomes.

Synthetic polypeptides: from polymer design to supramolecular assembly and biomedical application

This review highlights the recent advances in the chemical design, supramolecular assembly, and biomedical application of synthetic polypeptides fromN-carboxyanhydrides.

Co-delivery of VP-16 and Bcl-2-targeted antisense on PEG-grafted oMWCNTs for synergistic in vitro anti-cancer effects in non-small and small cell lung cancer

Present study describes the preparation of a polyethylene glycol-grafted oxidized multi-walled carbon nanotubes (oMWCNTs-PEG) hybrid nanosystem as a carrier of etoposide (VP-16) and Bcl-2 phosphorothioate antisense deoxyoligonucleotides (Aso) to achieve a superior cytostastic efficacy in non-small and small cell lung cancer in vitro. We have demonstrated that the adsorption of hydrophobic VP-16 and Bcl-2 Aso results in a stable nanotransporter exhibiting good dispersion with excellent release profiles (both, in pH 7.4 and 4.8) and negligible hemolytic activity (up to 6.5%). The evaluation of cytotoxicity was carried out in in vitro using small cell (SCLC; DMS53) and non-small cell lung cancer (NSCLC; NCIH2135) cell lines. It was found that Bcl-2 interference significantly increased the anti-cancer efficiency of VP-16 in the chemoresistant NSCLC cells. This was further supported using a flow-cytometry (Annexin V/propidium iodide assay), which revealed a significant increase in apoptotic cells in both the cell lines after the co-administration of VP-16 and Bcl-2 Aso using oMWCNTs-PEG hybrid, and fluorescence microscopy, which showed an increase in reactive oxygen species identified after Bcl-2 knock-down. Overall, oMWCNTs-PEG provided an exceptional biocompatible vehicle enabling the internalization of negatively charged nucleic acids and pH-sensitive release of cargoes in a hypoxic environment of the most of solid tumors. Moreover, Aso specifically binding to the first six codons of the Bcl-2 mRNA gave a satisfactorily decrease in Bcl-2 translation and an increase in NCIH2135 chemosensitivity towards VP-16.

Combining disulfiram and poly(l-glutamic acid)-cisplatin conjugates for combating cisplatin resistance

A poly(l-glutamic acid) graft polyethylene glycol-cisplatin complex (PGA-CisPt) performs well in reducing the toxicity of free cisplatin and greatly enhances the accumulation and retention of cisplatin in solid tumors. However, there is a lack of effective treatment options for cisplatin-resistant tumors. A major reason for this is the dense PEG shell, which ensures that the PGA-CisPt maintains a long retention time in the blood that may result in it bypassing the tumor cells or failing to be endocytosed within the tumor microenvironment. Consequently, the cisplatin from PGA-CisPt is released to the extracellular space in the presence of cisplatin-resistant tumor cells and the resistant problem to free cisplatin still valid. Therefore, we devised a strategy to combat the resistance of cisplatin in the tumor microenvironment using nanoparticles-loaded disulfiram (NPs-DSF) as a modulator. In vitro, cisplatin, in combination with DSF, had a synergistic effect and decreased cell survival rate of cisplatin-resistant A549DDP cells. This effect was also observed when combining PGA-CisPt with NPs-DSF. Similarly, in Balb/C nude mice with A549DDP xenografts, NPs-DSF improved PGA-CisPt effectiveness in inhibiting tumor growth while maintaining low toxicity. Our data demonstrate that DSF reduces intracellular glutathione (GSH) levels, inhibits NFκB activity, and modulates the expression of apoptosis-related proteins Bcl-2 and Bax, thereby improves the effectiveness of cisplatin in resistant cell lines. Here, we provide a promising method for overcoming cisplatin resistance in tumors, while maintaining the in vivo benefits of the PGA-CisPt complex.

Teniposide-loaded multilayer modified albumin nanoparticles with increased passive delivery to the lung

The structure of the albumin core and multi-coated layers are designed to encapsulate teniposide for achieving controlled release and passively targeted delivery to the lung.

A cooperative polymeric platform for tumor-targeted drug delivery

A tumor-targeted drug delivery system with small-molecule vascular disrupting agents inducing coagulation environment inside tumor and coagulation-targeted nanoparticles accumulating there.

In the pursuit of effective treatments for cancer, an emerging strategy is “active targeting”, where nanoparticles are decorated with targeting ligands able to recognize and bind specific receptors overexpressed by tumor cells or tumor vasculature so that a greater fraction of the administered drugs are selectively trafficked to tumor sites. However, the implementation of this strategy has faced a major obstacle. The interpatient, inter- and intra-tumoral heterogeneity in receptor expression can pose challenges for the design of clinical trials and result in the paucity of targetable receptors within a tumor, which limits the effectiveness of “active targeting” strategy in cancer treatment. Here we report a cooperative drug delivery platform that overcomes the heterogeneity barrier unique to solid tumors. The cooperative platform comprises a coagulation-inducing agent and coagulation-targeted polymeric nanoparticles. As a typical small-molecule vascular disrupting agent (VDA), DMXAA can create a unique artificial coagulation environment with additional binding sites in a solid tumor by locally activating a coagulation cascade. Coagulation-targeted cisplatin-loaded nanoparticles, which are surface-decorated with a substrate of activated blood coagulation factor XIII, can selectively accumulate in the solid tumor by homing to the VDA-induced artificial coagulation environment through transglutamination. In vivo studies show that the cooperative tumor-selective platform recruits up to 7.5-fold increases in therapeutic cargos to the tumors and decreases tumor burden with low systemic toxicity as compared with non-cooperative controls. These indicate that the use of coagulation-targeted nanoparticles, in conjunction with free small-molecule VDAs, may be a valuable strategy for improving standard chemotherapy.

Cisplatin-Induced Formation of Biocompatible and Biodegradable Polypeptide-Based Vesicles for Targeted Anticancer Drug Delivery

Novel cisplatin (CDDP)-loaded, polypeptide-based vesicles for the targeted delivery of cisplatin to cancer cells have been prepared. These vesicles were formed from biocompatible and biodegradable maleimide-poly(ethylene oxide)114-b-poly(L-glutamic acid)12 (Mal-PEG114-b-PLG12) block copolymers upon conjugation with the drug itself. CDDP conjugation forms a short, rigid, cross-linked, drug-loaded, hydrophobic block in the copolymer, and subsequently induces self-assembly into hollow vesicle structures with average hydrodynamic diameters (Dh) of ∼ 270 nm. CDDP conjugation is critical to the formation of the vesicles. The reactive maleimide-PEG moieties that form the corona and inner layer of the vesicles were protected via formation of a reversible Diels-Alder (DA) adduct throughout the block copolymer synthesis so as to maintain their integrity. Drug release studies demonstrated a low and sustained drug release profile in systemic conditions (pH = 7.4, [Cl(-)] = 140 mM) with a higher "burst-like" release rate being observed under late endosomal/lysosomal conditions (pH = 5.2, [Cl(-)] = 35 mM). Further, the peripheral maleimide functionalities on the vesicle corona were conjugated to thiol-functionalized folic acid (FA) (via in situ reduction of a novel bis-FA disulfide, FA-SS-FA) to form an active targeting drug delivery system. These targeting vesicles exhibited significantly higher cellular binding/uptake into and dose-dependent cytotoxicity toward cancer cells (HeLa) compared to noncancerous cells (NIH-3T3), which show high and low folic acid receptor (FR) expression, respectively. This work thus demonstrates a novel approach to polypeptide-based vesicle assembly and a promising strategy for targeted, effective CDDP anticancer drug delivery.