Dual Drug Backboned Shattering Polymeric Theranostic Nanomedicine for Synergistic Eradication of Patient-Derived Lung Cancer

Gold Nanoparticles Cure Bacterial Infection with Benefit to Intestinal Microflora

Antibiotics that are most used to cure bacterial infections in the clinic result in the imbalance of intestinal microflora, destroy the intestinal barrier, and induce bacterial resistance. There is an urgent need for antibacterial agent therapy for bacterial infections that does not destroy intestinal microflora. Herein, we applied 4,6-diamino-2-pyrimidinethiol (DAPT)-coated Au nanoparticles (D-Au NPs) for therapy of bacterial infection induced by Escherichia coli ( E. coli) in the gut. We cultured D-Au NPs and E. coli in an anaerobic atmosphere to evaluate their bactericidal effect. We studied the microflora, distribution of Au, and biomarkers in mice after a 28-day oral administration to analyze the effect of Au NPs on mice. D-Au NPs cured bacterial infections more effectively than levofloxacin without harming intestinal microflora. D-Au NPs showed great potential as alternatives to oral antibiotics.

Light-Activatable Prodrug and AIEgen Copolymer Nanoparticle for Dual-Drug Monitoring and Combination Therapy

Polyprodrug nanoparticles have been employed recently for safer and more effective cancer treatment. However, it remains a challenge to elucidate how and when the polyprodrug nanoparticles are dissociated and activated to release active drugs in cancer cells. Herein, a visible light-activatable Pt(IV) prodrug and an aggregation-induced emission luminogen (AIEgen) were copolymerized and embedded in the main chain of PtAIECP, and the chemotherapeutic doxorubicin (DOX) was subsequently encapsulated in the nanoparticles self-assembled by PtAIECP (PtAIECP@DOX NP). PtAIECP@DOX NP enabled the monitoring of both the light-activation of Pt(IV) prodrug to active Pt(II) and release of encapsulated DOX intracellularly through the fluorescence "turn-on" in the course of visible-light-induced polymer-main-chain cleavage and self-assembled structure dissociation in vitro and ex vivo. The synergistic anticancer efficacy of the activated Pt(II) drug and DOX in PtAIECP@DOX NP was also investigated in vitro and in vivo. The implementation of polyprodrug and AIE combination strategy empowered dual drug release and monitoring, which could be further used to guide the temporal and spatial control of light irradiation to maximize therapeutic efficiency, and will inspire other combinational bioimaging and therapy strategies.

A modular theranostic platform for tumor therapy and its metabolic studies

Theranostic systems are able to detect and treat diseases with only one procedure, thus greatly lessening the pain of patients. Since each patient's disease can be considered as a new clinical subtype, it is essential to develop theranostic nanomaterials with changeable functions for personal treatment. In this work, a novel modular theranostic platform was designed to control the stimuli-responsive drug release. As a patch board, mesoporous silica nanoparticles (MSNs) were functionalized with a linear pH-responsive benzimidazole (Bz)-polyethylene glycol (PEG) chain containing a redox-responsive ferrocene (Fc) oxide stopper at the end. As the plug, the β-CD ring was initially located at the Bz position. In an acidic tumor microenvironment, the pH sensitive Bz was protonated and the complex formation constant between Bz and β-CD decreased. At the same time, the complex formation constant between Fc and β-CD increased remarkably. As a result, the β-CD ring would depart from the nanoparticle surface to the Fc position at pH 6.2 & 10 mM GSH, physically causing an "And" logic gate type drug release. Herein, a "plug and play" method was used to achieve changeable functions with only one platform. By plugging modified β-CD into the patch board, theranostic systems with changeable functions can be achieved easily.

Recent Progress in the Theranostics Application of Nanomedicine in Lung Cancer

Lung cancer is one of the leading causes of cancer-related death worldwide. Non-small cell lung cancer (NSCLC) causes around 80% to 90% of deaths. The lack of an early diagnosis and inefficiency in conventional therapies causes poor prognosis and overall survival of lung cancer patients. Recent progress in nanomedicine has encouraged the development of an alternative theranostics strategy using nanotechnology. The interesting physico-chemical properties in the nanoscale have generated immense advantages for nanoparticulate systems for the early detection and active delivery of drugs for a better theranostics strategy for lung cancer. This present review provides a detailed overview of the recent progress in the theranostics application of nanoparticles including liposomes, polymeric, metal and bio-nanoparticles. Further, we summarize the advantages and disadvantages of each approach considering the improvement for the lung cancer theranostics.

Cisplatin: The first metal based anticancer drug

Cisplatin or (SP-4-2)-diamminedichloridoplatinum(II) is one of the most potential and widely used drugs for the treatment of various solid cancers such as testicular, ovarian, head and neck, bladder, lung, cervical cancer, melanoma, lymphomas and several others. Cisplatin exerts anticancer activity via multiple mechanisms but its most acceptable mechanism involves generation of DNA lesions by interacting with purine bases on DNA followed by activation of several signal transduction pathways which finally lead to apoptosis. However, side effects and drug resistance are the two inherent challenges of cisplatin which limit its application and effectiveness. Reduction of drug accumulation inside cancer cells, inactivation of drug by reacting with glutathione and metallothioneins and faster repairing of DNA lesions are responsible for cisplatin resistance. To minimize cisplatin side effects and resistance, combination therapies are used and have proven more effective to defect cancers. This article highlights a systematic description on cisplatin which includes a brief history, synthesis, action mechanism, resistance, uses, side effects and modulation of side effects. It also briefly describes development of platinum drugs from very small cisplatin complex to very large next generation nanocarriers conjugated platinum complexes.

Smart nanoplatform for sequential drug release and enhanced chemo-thermal effect of dual drug loaded gold nanorod vesicles for cancer therapy

Background

The combination of multiple chemotherapeutics has been used in the clinic for enhanced cancer chemotherapy, however, frequent relapse, chemo-resistance and side effects remains therapeutic hurdles. Thus, the development of co-delivery system with enhanced targeting and synergistic different modal treatments has been proposed as promising strategies for intensive improvement of the therapeutic outcomes.

Results

We fabricated a nanocarrier based on gold nanorods (Au NRs), cRGD peptide-modified and multi-stimuli-responsive paclitaxel (PTX) and curcumin (CUR) release for synergistic anticancer effect and chemo-photothermal therapy (PTX/CUR/Au NRs@cRGD). The specific banding of cRGD to αvβ3 integrin receptor on the tumor cell surfaces facilitated the endocytosis of PTX/CUR/Au NRs@cRGD, and the near-infrared ray (NIR) further enhanced the drug release and chemotherapeutical efficiency. Compared to single drug, single model treatment or undecorated-PTX/CUR/Au NRs, the PTX/CUR/Au NRs@cRGD with a mild NIR showed significantly enhanced apoptosis and S phase arrest in three cancer cell lines in vitro, and improved drug accumulation in tumor sites as well as tumor growth inhibition in vivo.

Conclusions

The tumor targeted chemo-photothermal therapy with the synergistic effect of dual drugs provided a versatile strategy for precise cancer therapy.

Electronic supplementary material

The online version of this article (10.1186/s12951-019-0473-3) contains supplementary material, which is available to authorized users.

Pre-blocked molecular shuttle as an in-situ real-time theranostics

Real-time monitor of drug-release from drug formulations in a noninvasive way can provide spatio-temporal information for drug activation and guide further clinical rational administration. In this work, a molecular shuttle, as a typical nanosized artificial molecular machine, was managed to act as a conceptually-new nanotheranostics for oxaliplatin. A post-recognition strategy was utilized, where a default supramolecular-dye couple was pre-blocked. The rational design, synthesis, characterization and proof-of-concept of this strategy were described in detail. The drug-release upon reducing environment can be translated into near-infrared (NIR) fluorescence signal (OFF-to-ON), allowing to track the drug-release procedure by multi-modal images including IVIS, FLECT and photoacoustic imaging. The versatile nanotheranostics system can target to triple negative breast tumor via conjugated F3 peptide, and show an improved anti-tumor efficacy with much lower side effect. The intelligent nanotheranostics system based on molecular shuttle provides new reference for precision medicine in preclinical trial and postclinical evaluation.

Evaluation of Polymer Nanoformulations in Hepatoma Therapy by Established Rodent Models

Hepatoma is one of the most severe malignancies usually with poor prognosis, and many patients are insensitive to the existing therapeutic agents, including the drugs for chemotherapy and molecular targeted therapy. Currently, researchers are committed to developing the advanced formulations with controlled drug delivery to improve the efficacy of hepatoma therapy. Numerous inoculated, induced, and genetically engineered hepatoma rodent models are now available for formulation screening. However, animal models of hepatoma cannot accurately represent human hepatoma in terms of histological characteristics, metastatic pathways, and post-treatment responses. Therefore, advanced animal hepatoma models with comparable pathogenesis and pathological features are in urgent need in the further studies. Moreover, the development of nanomedicines has renewed hope for chemotherapy and molecular targeted therapy of advanced hepatoma. As one kind of advanced formulations, the polymer-based nanoformulated drugs have many advantages over the traditional ones, such as improved tumor selectivity and treatment efficacy, and reduced systemic side effects. In this article, the construction of rodent hepatoma model and much information about the current development of polymer nanomedicines were reviewed in order to provide a basis for the development of advanced formulations with clinical therapeutic potential for hepatoma.

Green Mass Production of Pure Nanodrugs via an Ice-Template-Assisted Strategy

To make nanomedicine potentially applicable in a clinical setting, several methods have been developed to synthesize pure nanodrugs (PNDs) without using any additional inert carriers. In this work, we report a novel green, low-cost, and scalable ice-template-assisted approach which shows several unique characteristics. First, the whole process only requires adding a drug solution into an ice template and subsequent melting (or freeze-drying), allowing easy industrial mass production with low capital investment. Second, the production yield is much higher than that of the traditional reprecipitation approach. The yield of Curcumin (Cur) PNDs is over two orders (∼140 times) magnitude higher than that obtained in a typical reprecipitation preparation. By adjusting simple processing parameters, PNDs with different sizes (∼20-200 nm) can be controllably obtained. Finally, the present approach can be easily applicable for a wide range of hydrophobic therapeutic drugs without any structural modification.

Polypeptide Nanogels With Different Functional Cores Promote Chemotherapy of Lung Carcinoma

Two kinds of tumor microenvironment-responsive polypeptide nanogels were developed for intracellular delivery of cytotoxics to enhance the antitumor efficacies and reduce the side effects in the chemotherapy of lung carcinoma. The sizes of both doxorubicin (DOX)-loaded nanogels methoxy poly(ethylene glycol)-poly(L-phenylalanine-co-L-cystine) [mPEG-P(LP-co-LC)] and methoxy poly(ethylene glycol)-poly(L-glutamic acid-co-L-cystine) [mPEG-P(LG-co-LC)] (NGP/DOX and NGG/DOX) were less than 100 nm, which was appropriate for the enhanced permeability and retention (EPR) effect. The bigger and smaller scale of nanoparticle could induce the elimination of reticuloendothelial system (RES) and decrease the in vivo circulating half-life, respectively. The loading nanogels were stable in the neutral environment while quickly degraded in the mimic intracellular microenvironment. Furthermore, the DOX-loaded reduction-responsive nanogels showed significantly higher tumor cell uptake than free DOX⋅HCl as time went on from 2 to 6 h. In addition, these DOX-loaded nanogels showed efficient antitumor effects in vivo, which was verified by the obviously increased necrosis areas in the tumor tissues. Furthermore, these DOX-loaded nanogels efficiently reduced the side effects of DOX. In conclusion, these reduction-responsive polypeptides based nanogels are suitable for the efficient therapy of lung carcinoma.

GSH-sensitive Pt(IV) prodrug-loaded phase-transitional nanoparticles with a hybrid lipid-polymer shell for precise theranostics against ovarian cancer

Background: Platinum (II) (Pt(II))-based anticancer drugs dominate the chemotherapy field of ovarian cancer. However, the patient's quality of life has severely limited owing to dose-limiting toxicities and the advanced disease at the time of diagnosis. Multifunctional tumor-targeted nanosized ultrasound contrast agents (glutathione (GSH)-sensitive platinum (IV) (Pt(IV)) prodrug-loaded phase-transitional nanoparticles, Pt(IV) NP-cRGD) were developed for precise theranostics against ovarian cancer. Methods: Pt(IV) NP-cRGD were composed of a perfluorohexane (PFH) liquid core, a hybrid lipid-polymer shell with PLGA12k-PEG2k and DSPE-PEG1k-Pt(IV), and an active targeting ligand, the cRGD peptide (PLGA: poly(lactic-co-glycolic acid), PEG: polyethylene glycol, DSPE: 1,2-distearoyl-sn-glycero-3-phosphoethanolamine, cRGD: cyclic Arg-Gly-Asp). Pt(IV), a popular alternative to Pt(II), was covalently attached to DSPE-PEG1k to form the prodrug, which fine-tuned lipophilicity and improved cellular uptake. The potential of Pt(IV) NP-cRGD as contrast agents for ultrasound (US) imaging was assessed in vitro and in vivo. Moreover, studies on the antitumor efficiency and antitumor mechanism of Pt(IV) NP-cRGD assisted by US were carried out. Results: Pt(IV) NP-cRGD exhibited strong echogenic signals and excellent echo persistence under an US field. In addition, the GSH-sensitive and US-triggered drug delivery system maximized the therapeutic effect while reducing the toxicity of chemotherapy. The mechanistic studies confirmed that Pt(IV) NP-cRGD with US consumed GSH and enhanced reactive oxy gen species (ROS) levels, which further causes mitochondria-mediated apoptosis. Conclusion: A multifunctional nanoplatform based on phase-transitional Pt(IV) NP-cRGD with US exhibited excellent echogenic signals, brilliant therapeutic efficacy and limited side effect, suggesting precise theranostics against ovarian cancer.

Oxygen Vacancies Enhanced CeO2:Gd Nanoparticles for Sensing a Tumor Vascular Microenvironment by Magnetic Resonance Imaging

The specific characteristics of the tumor vascular microenvironment such as microvascular permeability and water diffusion have been demonstrated to play essential roles in the evaluation of infiltration of tumors. However, at present, there are few contrast agents (CAs) for magnetic resonance imaging to enhance the sensitivity for acquiring this vital information. Herein, we develop Gd-doped (CeO₂:Gd) nanoparticles as CAs to detect the tumor vascular microenvironment with high sensitivity. The lattice oxygen vacancies on the surface of CeO₂:Gd nanoparticles could bind considerable water molecules to improve the r₁ value, achieving an excellent dynamic contrast-enhanced perfusion weighted imaging performance for the measurement of microvascular permeability. Diffusion limiting of water molecules by oxygen vacancies of CeO₂:Gd nanoparticles further enhances the diffusion-weighted magnetic resonance imaging signal in vitro and in vivo. Excitingly, the strategy is not only essential for obtaining tumor vascular microenvironment information but also offers a way for further research in the design of magnetic resonance CAs.

Sandwich-Like Fibers/Sponge Composite Combining Chemotherapy and Hemostasis for Efficient Postoperative Prevention of Tumor Recurrence and Metastasis

Intraoperative bleeding is an essential factor leading to the earliest recurrence and tumor metastasis frequently seen after resection of solid tumors. Local drug delivery implants show the unique advantages on postoperative cancer therapy. Herein, a sandwich-like cisplatin-loaded fibers/sponge composite (CFSC) combining chemotherapy and hemostasis is constructed. The obtained implantable CFSC is able to simultaneously stop bleeding and absorb disseminated tumor cells after tumor resection. More importantly, sustained released cisplatin can kill local residual tumor cells as well as those concentrated in the CFSC, which significantly inhibits local tumor recurrence and distant tumor metastasis on the subcutaneous postoperative recurrence model and metastasis models. This dual functional implant strategy with low toxicity to healthy organs may inspire new aspects for efficient postoperative cancer therapy.

Lighting-Up Tumor for Assisting Resection via Spraying NIR Fluorescent Probe of γ-Glutamyltranspeptidas

For the precision resection, development of near-infrared (NIR) fluorescent probe based on specificity identification tumor-associated enzyme for lighting-up the tumor area, is urgent in the field of diagnosis and treatment. Overexpression of γ-glutamyltranspeptidase, one of the cell-membrane enzymes, known as a biomarker is concerned with the growth and progression of ovarian, liver, colon and breast cancer compared to normal tissue. In this work, a remarkable enzyme-activated NIR fluorescent probe NIR-SN-GGT was proposed and synthesized including two moieties: a NIR dicyanoisophorone core as signal reporter unit; γ-glutamyl group as the specificity identification site. In the presence of γ-GGT, probe NIR-SN-GGT was transformed into NIR-SN-NH₂, the recovery of Intramolecular Charge Transfer (ICT), liberating the NIR fluorescence signal, which was firstly employed to distinguish tumor tissue and normal tissues via simple “spraying” manner, greatly promoting the possibility of precise excision. Furthermore, combined with magnetic resonance imaging by T2 weight mode, tumor transplanted BABL/c mice could be also lit up for first time by NIR fluorescence probe having a large stokes, which demonstrated that probe NIR-SN-GGT would be a useful tool for assisting surgeon to diagnose and remove tumor in clinical practice.

Multifunctional Cargo-Free Nanomedicine for Cancer Therapy

Nanocarriers encapsulating multiple chemotherapeutics are a promising strategy to achieve combinational chemotherapy for cancer therapy; however, they generally use exotic new carriers without therapeutic effect, which usually suffer from carrier-related toxicity issues, as well as having to pass extensive clinical trials to be drug excipients before any clinical applications. Cargo-free nanomedicines, which are fabricated by drugs themselves without new excipients and possess nanoscale characteristics to realize favorable pharmacokinetics and intracellular delivery, have been rapidly developed and drawn much attention to cancer treatment. Herein, we discuss recent advances of cargo-free nanomedicines for cancer treatment. After a brief introduction to the major types of carrier-free nanomedicine, some representative applications of these cargo-free nanomedicines are discussed, including combination therapy, immunotherapy, as well as self-monitoring of drug release. More importantly, this review draws a brief conclusion and discusses the future challenges of cargo-free nanomedicines from our perspective.

Tailoring Platinum(IV) Amphiphiles for Self-Targeting All-in-One Assemblies as Precise Multimodal Theranostic Nanomedicine

Drug, targeting ligand, and imaging agent are the three essential components in a nanoparticle-based drug delivery system. However, tremendous batch-to-batch variation of composition and drug content typically accompany the current approaches of building these components together. Herein, we report the design of photoactivatable platinum(IV) (Pt(IV)) amphiphiles containing one or two hydrophilic lactose targeting ligands per hydrophobic Pt(IV) prodrug for an all-in-one precise nanomedicine. Self-assembly of these Pt(IV) amphiphiles results in either micelle or vesicle formation with a fixed Pt/targeting moiety ratio and a constantly high content of Pt. The micelles and vesicles are capable of hepatoma cell-targeting, fluorescence/Pt-based CT imaging and have shown effective anticancer efficacy under laser irradiation in vitro and in vivo. This photoactivatable, active self-targeting, and multimodal theranostic amphiphile strategy shows great potential in constructing precise nanomedicine.

Cancer nanomedicine: mechanisms, obstacles and strategies

Targeting nanoparticles to cancers for improved therapeutic efficacy and decreased side effects remains a popular concept in the past decades. Although the enhanced permeability and retention effect serves as a key rationale for all the currently commercialized nanoformulations, it does not enable uniform delivery of nanoparticles to all tumorous regions in all patients with sufficient quantities. Also, the increase in overall survival is often modest. Many factors may influence the delivering process of nanoparticles, which must be taken into consideration for the promise of nanomedicine in patients to be realized. Herein, we review the mechanisms and influencing factors during the delivery of cancer therapeutics and summarize current strategies that have been developed for the fabrication of smart drug delivery systems.

Polylactide-tethered prodrugs in polymeric nanoparticles as reliable nanomedicines for the efficient eradication of patient-derived hepatocellular carcinoma

Nanomedicines have been extensively explored for cancer treatment, and their efficacies have arguably been proven in various cancer cell-derived xenograft (CDX) mouse models. However, they generally fail to show such therapeutic advantages in patients because of the huge pathological differences between human tumors and CDX models. Methods: In this study, we fabricated colloidal ultrastable nanomedicines from polymeric prodrugs and compared the therapeutic efficacies in hepatocellular carcinoma (HCC) CDX and clinically relevant patient-derived xenograft (PDX) mouse models, which closely mimic human tumor pathological properties. Working towards this goal, we esterified a highly potent SN38 (7-ethyl-10-hydroxycamptothecin) agent using oligo- or polylactide (oLA or PLA) segments with varying molecular weights. Results: The resulting SN38 conjugates assembled with polyethylene glycol-block-polylactic acid to form systemically injectable nanomedicines. With increasing PLA chain length, the SN38 conjugates showed extended retention in the nanoparticles and superior antitumor activity, completely eradicating xenografted tumors in both mouse models. Our data implicate that these small-sized and ultrastable nanomedicines might also efficaciously treat cancer in patients. More interestingly, the systemically delivered nanomedicines notably alleviated the incidence of bloody diarrhea. Conclusion: Our studies demonstrate that the appropriate molecular editing of anticancer drugs enables the generation of better tolerated cytotoxic nanotherapy for cancer, which represents a potentially useful scaffold for further clinical translation.

A DOX-loaded polymer micelle for effectively inhibiting cancer cells

A novel triblock polymer is synthesized and self-assembled with doxorubicin to form DOX-loaded micelles. The synthetic process involves the ring-opening polymerization, carboxylation and amidation reactions, and the structures are characterized. The drug release test indicated that the micelles have the ability to control the release of drugs. The cell uptake results indicated that the DOX-loaded micelles could enter cancer cells easily, and the cytotoxicity and apoptosis test confirmed that DOX-loaded micelles have a strong killing effect on tumor cells, while the blank micelles do not have cytotoxicity. Therefore, the novel polymer micelles are a promising carrier for delivery of anticancer drugs to enhance cancer treatment.

A novel triblock polymer is synthesized and self-assembled with doxorubicin to form DOX-loaded micelles.