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Hypoxia is one of the key characteristics of solid tumors. The over-expression of azoreductase resulting from hypoxia can be used as a target to visualize hypoxic levels and a trigger of the drug release system in tumor treatment. In this work, we developed a near-infrared fluorescent probe YLOD, composed of a near-infrared fluorophore, an azo bond, and an analogue of the anti-tumor drug melphalan. In the presence of azoreductase, YLOD displayed a red emission at 620 nm and released the anti-tumor drug concomitantly, thus achieving the integrated effects of hypoxic imaging and tumor treatment. Furthermore, YLOD successfully inhibited the growth of solid tumors during the tumor suppression experiments in nude mice. Considering all the results, YLOD emerges as a new fluorescence tool that can quickly determine the location and the edges of a tumor, showing concrete potential in clinical cancer treatment.

Background: Tumors are still among the major challenges to human health. Tumor-targeted therapy is an effective way to treat tumors based on precise medical models. Sialic acid (SA) is overexpressed on the surface of tumor cells, and Phenyl Boric Acid (PBA) can specifically bind to SA. However, studies on the use of PBA in tumor-targeted therapy are few. Objective: To summarize and analyze the characteristics and influencing factors of tumor targeted therapy in recent years, and the influencing factors of phenyl boric acid modified polymers in tumor targeted therapy, such as hydrogen ion concentration (pH), Adenosine Triphosphate (ATP), and sugars. This paper describes the application of phenyl boric acid partially functionalized nano-polymers in various types of targeted tumors, such as breast cancer, lung adenocarcinoma, liver cancer, and so forth. In order to further improve the basic research and clinical workers' understanding of nano-preparations and tumor targeted therapy. At the same time, it is also expected to promote the development value of phenyl boric acid. Methods: The findings on tumor-targeted therapy and the role of partially functionalized polymers with PBA in different tumors at home and abroad has been analyzed and summarized in recent years. Results: Tumor-targeted therapy is a promising treatment for tumors. PBA promotes the treatment of tumors using SA, which is highly expressed on the surface of tumor cells. Conclusions: Tumor-targeted therapy has shown great prospects for clinical application in recent years. PBA is beneficial as a member of the drug loading system. Further studies are still needed to promote its development and application.

Considering that pathological hallmarks are directly related to structural and chemical information of tumor, noninvasive, real-time, spatially resolved quantitative chemical imaging is significant for treatment decisions. The discovery of the transparency window of biological tissues and the advancement of near-infrared technology provide exciting prospects for in vivo imaging. Herein, an engineering apoferritin-conjugated cypate nanoprobe is fabricated for near-infrared photoacoustic imaging and fluorescence imaging in the first and second window. As the analogue of indocyanine green, dicarboxylic cypate is directly conjugated with the apoferritin molecules for forming assembly nanoprobes. Resulting from the intrinsic targeting and optical capacity of the nanoprobes, the triple near-infrared imaging can perform multimeasurements of the target analyte in real-time. This imaging methodology not only provides the structural background information of the tumor, each pixel also contains quantitative in situ information of the tumor. In particular, part of the absorbed light energy is released as heat energy in the near-infrared photoacoustic imaging process. The constructed triple near-infrared nanoprobes therefore naturally navigate the photothermal treatment plan of tumor and finally realize the efficient assistance of tumor photothermal ablation. The tumor metabolomics reveal that the nanoprobe-assisted tumor ablation has a potential mechanism toward glutamine- and phenylalanine-related metabolism perturbation and the disordered oxidative stress state. The tumor-specific bioconjugate nanoprobes hold great potential as a versatile theranostic platform for tumor imaging and therapy.

Black phosphorus (BP) nanosheets with excellent features have been broadly employed for cancer therapy. BPs in blood were known to form BP nanomaterial–corona complexes, yet not explored their biol...

The diagnosis and therapy of tumors are challenging problems in the medical field. Peptides are derived from living organisms with excellent biocompatibility, low-toxicity/non-toxicity, and negligible immunogenicity, and they have been widely used in the field of biomedicine, especially in tumor sensing and treatment. In recent years, a series of technologies in peptide research (including polypeptide synthesis, phage screening, sequencing, and computer-aided molecular simulations) and the discovery of tumor targeting peptide have been developed. In this review, we summarized the progress of peptide-based materials in tumor therapy, including the development and screening of peptides, and two peptide targeting tumor strategies: targeting tumor high-expressing receptors and targeting tumor microenvironment. We also summarized various tumor imaging methods and treatment methods based on peptides. Furthermore, the advantages and challenges of peptides in the current tumor field and the possible solutions are also discussed.

Theranostics, which affords both therapeutic and diagnostic functions within a single entity has emerged as a cutting-edge technology for the development of personalized nanomedicine. Nanoparticles also offer the potential to unlock new avenues in cancer theranostics, attributing to their capacity for multifunctionality and multivalency. Lanthanide-doped upconversion nanoparticles (UCNPs) constitute a promising nano-scale platform notable for their unique ability to convert near-infrared (NIR) light into higher-energy luminescence. In addition to the large anti-Stokes shift, UCNPs also feature multiple sharp emission peaks varying from ultraviolet (UV) to NIR region, long luminescence lifespan, and high stabiltiy against photobleaching. By using NIR irradiation as an exciting source, UCNPs enable deep-tissue bioimaging, controlled cargo release and subesquent therapeutic actions with high spatial and temporal resolution. On the other hand, to accomplish site-specific targetability to maximize theranostic outcomes, active targeting directed by specific tumor-homing ligands has been proven to be efficacious in improving tumor accumulation and reducing side effect. The choice of targeting ligands falls into several general classes including small molecules, peptides, proteins, antibodies, carbohydrates, or nucleic acid aptamers. Ligand-mediated targeting of functionalized UCNPs tailored with cancer-specific recognition moieties will lead to enhanced cellular uptake and permeability in tumor tissues, and thus achieving effective theranostic treatments and long-term prognosis. In this perspective, we discuss the provision and prospects of specific ligands functionalized UCNPs for targeted delivery and theranostic application in various types of tumor therapies.

A simple and feasible atom-precise biotinylated Cu(i) complex, which can catalyze H2O2 overexpressed commonly in the tumor microenvironment to produce ˙OH through a Fenton-like reaction, was prepared and employed as an effective agent for tumor-targeted chemodynamic therapy.

Selective intracellular transportation of RNA interference (RNAi) into the cytosol of tumor cells is deemed as an intriguing strategy for treatment of intractable tumors. Pertaining to sequential biological barriers, polymeric RNAi therapeutics were engineered by covalent conjugation of multiple small interference RNA (siRNA) molecules onto a polylysine (PLys) segment of cyclic Arg-Gly-Asp (RGD)-poly(ethylene glycol)

Imaging-guiding and targeted drug delivery to tumors are essential for precision cancer therapy, which is a challenging goal to achieve extraordinary therapeutic efficacy. Functional live cells-based delivery systems are expected to play an important role in imaging-guiding and targeted drug delivery. Herein, we fabricated a delivery system mediated by IR-820 conjugated macrophages for tumor targeted combination therapy under fluorescence imaging guidance. The functional macrophages by nature could cross the barriers and recruit into tumors, and serve as host cells to targeted deliver drugs to tumors. The pH-sensitive doxorubicin nanoparticles were engulfed by the macrophages to enhance the drug loading and decrease the damage on host cells. IR-820 was anchored into macrophages cytoplasm to achieve the dual function of photothermal therapy and fluorescence imaging guidance. With Balb/C mice bearing murine breast tumor (4 T1) as models, the functional macrophages for their innate tumor tropism could targeted transport these therapeutic drugs into tumor site to exert efficient chemo-photothermal combination therapy. Moreover, fluorescence imaging-guided drug delivery was employed as the visible strategy to provide the optimized therapeutic window based on the fluorescence of IR-820. The multi-functional macrophages-mediated delivery system would provide a potential for precise and targeted delivery of combination therapy.

Background: Tumor-targeted delivery by nanoparticles is a great achievement towards the use of highly effective drug at very low doses. The conventional development of tumor-targeted delivery by nanoparticles is based on enhanced permeability and retention (EPR) effect and endocytosis based on receptor-mediated are very demanding due to the biological and natural complications of tumors as well as the restrictions on the design of the accurate nanoparticle delivery systems. Methods: Different tumor environment stimuli are responsible for triggered multistage drug delivery systems (MSDDS) for tumor therapy and imaging. Physicochemical properties, such as size, hydrophobicity and potential transform by MSDDS because of the physiological blood circulation different, intracellular tumor environment. This system accomplishes tumor penetration, cellular uptake improved, discharge of drugs on accurate time, and endosomal discharge. Results: Maximum drug delivery by MSDDS mechanism to target therapeutic cells and also tumor tissues and sub cellular organism. Poorly soluble compounds and bioavailability issues have been faced by pharmaceutical industries, which are resolved by nanoparticle formulation. Conclusion: In our review, we illustrate different types of triggered moods and stimuli of the tumor environment, which help in smart multistage drug delivery systems by nanoparticles, basically a multi-stimuli sensitive delivery system, and elaborate their function, effects, and diagnosis.

The design of bright NIR-II luminescent nanomaterials that enable efficient labelling of proteins without disturbing their physiological properties in vivo is challenging. We developed an efficient strategy to synthesize bright NIR-II gold nanoclusters (Au NCs) protected by biocompatible cyclodextrin (CD). Leveraging the ultrasmall size of Au NCs (

BACKGROUND: The immuno-metabolic interplay has gained interest for determining and targeting immunosuppressive tumor micro-environments that remain a barrier to current immuno-oncologic therapies in hepatocellular carcinoma. PURPOSE: To develop molecular MRI tools to reveal resistance mechanisms to immuno-oncologic therapies caused by the immuno-metabolic interplay in a translational liver cancer model. MATERIALS AND METHODS: A total of 21 VX2 liver tumor–bearing New Zealand white rabbits were used between October 2018 and February 2020. Rabbits were divided into three groups. Group A (n = 3) underwent intra-arterial infusion of gadolinium 160 ((160)Gd)–labeled anti–human leukocyte antigen–DR isotope (HLA-DR) antibodies to detect antigen-presenting immune cells. Group B (n = 3) received rhodamine-conjugated superparamagnetic iron oxide nanoparticles (SPIONs) intravenously to detect macrophages. These six rabbits underwent 3-T MRI, including T1- and T2-weighted imaging, before and 24 hours after contrast material administration. Group C (n = 15) underwent extracellular pH mapping with use of MR spectroscopy. Of those 15 rabbits, six underwent conventional transarterial chemoembolization (TACE), four underwent conventional TACE with extracellular pH– buffering bicarbonate, and five served as untreated controls. MRI signal intensity distribution was validated by using immunohistochemistry staining of HLA-DR and CD11b, Prussian blue iron staining, fluorescence microscopy of rhodamine, and imaging mass cytometry (IMC) of gadolinium. Statistical analysis included Mann-Whitney U and Kruskal-Wallis tests. RESULTS: T1-weighted MRI with (160)Gd-labeled antibodies revealed localized peritumoral ring enhancement, which corresponded to gadolinium distribution detected with IMC. T2-weighted MRI with SPIONs showed curvilinear signal intensity representing selective peritumoral deposition in macrophages. Extracellular pH–specific MR spectroscopy of untreated liver tumors showed acidosis (mean extracellular pH, 6.78 ± 0.09) compared with liver parenchyma (mean extracellular pH, 7.18 ± 0.03) (P = .008) and peritumoral immune cell exclusion. Normalization of tumor extracellular pH (mean, 6.96 ± 0.05; P = .02) using bicarbonate during TACE increased peri- and intratumoral immune cell infiltration (P = .002). CONCLUSION: MRI in a rabbit liver tumor model was used to visualize resistance mechanisms mediated by the immuno-metabolic interplay that inform susceptibility and response to immuno-oncologic therapies, providing a therapeutic strategy to restore immune permissiveness in liver cancer.

Self-assembling prodrugs represents a robust and effective nanotherapeutic approach for delivering poorly soluble anticancer drugs. With numerous intrinsic advantages, self-assembling prodrugs possess the maximum drug loading capacity, controlled drug release kinetics, prolonged blood circulation, and preferential tumor accumulation based on the enhanced permeability and retention (EPR) effect. These prodrug conjugates allow for efficient self-assembly into nanodrugs with the potential of encapsulating other therapeutic agents that have different molecular targets, enabling simultaneous temporal-spatial release of drugs for synergistic antitumor efficacy with reduced systemic side effects. The aim of this review is to summarize the recent progress of self-assembling prodrug cancer nanotherapeutics that are made through conjugating therapeutically active agents to Polyethylene glycol, Vitamin E, or drugs with different physicochemical properties via rational design, for synergistic tumor targeted drug delivery., Graphical abstract Image, graphical abstract

Cancer is the result of disturbed cell functions. Cancer is induced by the accumulation of many genetic and epigenetic changes within the cell, expressed in the accumulation of chromosomal or molecular aberrations, which then leads to genetic instability. Chemotherapy is a major option to treat cancer, yet classical treatments induce toxic effects. Alternatively, cancer nanomedicines with tumor-targeted properties are very promising for improved safety and efficacy. Nanomedicines are sub-micrometer formulations designed to improve the biodistribution of anticancer drugs, resulting in modified toxicity, less off-target localization, enhanced efficacy and improved accumulation at the target site. For designing a targeted nanodrug system, the pathophysiological characteristics of tumors should be studied. This article explains how to make smart nanomedicines based on tumor-associated pathological features. Advantages include selective cell uptake, better drug release, increased therapeutic efficiency, receptor-mediated cell endocytosis, enhanced permeability and retention, and reduced systemic effects.

Recent days, aggregatable nanoparticles, which can specifically respond to certain stimulus, have shown great potential in tumor-targeted drug delivery with prolonged retention and deeper penetration. In this review, we summarize recent advances in design of aggregatable nanoparticles by different stimuli. Internal (pH and enzyme) and external (light, temperature and ROS) stimuli are introduced for a comprehensive description. Moreover, the aggregated nanoparticles usually exhibit photothermal, photoacoustic, PET and enhanced MRI contrast, which is also described. In the end, we discuss about the potential applications and challenges for the future clinical translation.

The efficacy of nano-mediated drug delivery has been impeded by multiple biological barriers such as the mononuclear phagocyte system (MPS), as well as vascular and interstitial barriers. To overcome the abovementioned obstacles, we report a nano-pathogenoid (NPN) system that can in situ hitchhike circulating neutrophils and supplement photothermal therapy (PTT). Cloaked with bacteria-secreted outer membrane vesicles inheriting pathogen-associated molecular patterns of native bacteria, NPNs are effectively recognized and internalized by neutrophils. The neutrophils migrate towards inflamed tumors, extravasate across the blood vessels, and penetrate through the tumors. Then NPNs are rapidly released from neutrophils in response to inflammatory stimuli and subsequently taken up by tumor cells to exert anticancer effects. Strikingly, due to the excellent targeting efficacy, cisplatin-loaded NPNs combined with PTT completely eradicate tumors in all treated mice. Such a nano-platform represents an efficient and generalizable strategy towards in situ cell hitchhiking as well as enhanced tumor targeted delivery., The presence of several biological barriers impede the efficacy of nano-mediated drug delivery for solid cancer therapy. Here, the authors develop a nano-pathogenoid system that targets circulating neutrophils and show that it overcomes these biological barriers and improves tumour targeting and efficacy.

The second near-infrared (NIR-II, 1000-1700 nm) light-based diagnosis and therapy have received extensive attention for neoplastic disease treatments because of the fact that light in the NIR-II window possesses less photon scattering along with deeper tissue penetration than that in the NIR-I (700-950 nm) window. Herein, we present a Gd- and copper sulfide (CuS)-integrated nanogel (NG) platform for magnetic resonance (MR)/photoacoustic (PA) imaging-guided tumor-targeted photothermal therapy (PTT). In our approach, we prepared cross-linked polyethylenimine (PEI) NGs via an inverse emulsion method, modified the PEI NGs with Gd chelates, targeting ligand folic acid (FA) through a polyethylene glycol (PEG) spacer and 1,3-propanesultone, and finally loaded CuS nanoparticles (NPs) within the functional NGs. The as-synthesized Gd/CuS@PEI-FA-PS NGs with a mean size of 85 nm exhibit a good water dispersibility and protein resistance property, admirable r1 relaxivity (11.66 mM-1 s-1), excellent NIR-II absorption feature, high photothermal conversion efficiency (26.7%), and FA-mediated targeting specificity to cancer cells overexpressing FA receptor (FAR). With these properties along with the good cytocompatibility, the developed Gd/CuS@PEI-FA-PS NGs enable MR/PA dual-mode imaging-guided targeted PTT of FAR-overexpressing tumors under the irradiation of an NIR-II (1064 nm) laser. The designed Gd/CuS@PEI-FA-PS NGs may be used as a promising theranostic agent for MR/PA dual-mode imaging-guided PTT of other FAR-expressing tumors.

Among all X-ray tumor diagnostic imaging modalities, computed tomography (CT) has been most commonly used owing to its high spatial resolution and high detection efficiency. In order to achieve enhanced CT imaging on tumors, methacrylated iopamidol based polymer nanoparticles with disulfide bond crosslinking were prepared and then surface-modified with a cyclo[Arg-Gly-Asp-(D-Phe)-Cys] (cRGD) peptide through the linkages of poly(ethylene glycol) (PEG). The resultant poly(methacrylated iopamidol)-polyethylene glycol-cRGD (PMAI-PEG-RGD) nanoparticles were well-dispersed and had a relatively high X-ray attenuation coefficient. Compared to the nanoparticles without the modification of cRGD, PMAI-PEG-RGD nanoparticles showed specific uptake by 4T1 cells that over-express αvβ3 integrin. After being intravenously injected into 4T1 tumor-bearing mice, PMAI-PEG-RGD nanoparticles reached the tumor and further accumulated there efficiently, thus greatly enhancing the contrast of tumor CT imaging. In summary, PMAI-PEG-RGD nanoparticles have great potential to be used as a novel CT contrast agent for breast cancer-targeted imaging.

A tumor-targeted near-infrared (NIR) fluorophore CA800SO3 was developed for fluorescence-guided phototherapy. This new type of NIR fluorophore showed high tumor targetability based on the structure-inherent targeting approach. This fluorophore generated sufficient hyperthermia and reactive oxygen species (ROS) simultaneously for synergistic cancer phototherapy, induced by an 808 nm laser irradiation.

Tumor-targeted drug carriers are becoming attractive for precise drug delivery in anti-tumor therapy. However, a lot of the reported drug delivery systems are complicatedly designed and their destiny in vivo is beyond our control, which limited their clinical applications. Hence, it is urgently needed to develop spatio-manipulable self-propelled nanosystems for drug delivery in a facile way. Here, we have successfully constructed drug-internalized bacterial swimmers, whose movement can be manually controlled by an external magnetic field (MF). We demonstrate that the swimmers maintain the mobility to align and swim along MF lines. Further studies reveal that the doxorubicin (DOX-) internalized bacterial swimmers are able to navigate toward tumor sites under the guidance of MF, rendering enhanced anti-tumor efficacy compared with that of dead ones and free DOX. Therefore, the MF-guided bacterial swimmers hold great promise for spatio-manipulable drug delivery in precision medicine.

Simultaneous inhibitions of primary tumor growth and distant metastasis are very critical for cancer patients to improve their survival and cure rates. Although photodynamic therapy (PDT) shows great potential for primary tumor treatment, it often exacerbates hypoxia with a reduced therapeutic efficacy and subsequently contributes to carcinoma progression and metastatic dissemination. To solve these issues, self-delivery photodynamic nanoinhibitors (PNI) are developed for tumor targeted therapy and metastasis inhibition. PNI are composed of a carbonic anhydrase inhibitor (CAi), a hydrophilic poly(ethylene glycol) (PEG) linker, and a hydrophobic photosensitizer protoporphyrin IX (PpIX). Such self-delivery design of PNI avoids the premature release and heterogeneous distribution of CAi and PpIX to enhance the availability and synergism. Briefly, the CAi-based nanoinhibitors improve the selectivity of CAi for specific recognition and inhibition of tumor-associated isoform carbonic anhydrase (CA) IX, which would not only facilitate the targeted drug delivery of PNI but also regulate the hypoxia-induced signaling cascade and PDT resistance. Benefiting from the CA IX inhibition and targeted PDT, PNI exhibit a robust inhibitory effect on primary tumor growth and distant metastasis. This targeted self-delivery strategy sheds light on the photosensitizer-based molecular design to overcome the defect of traditional PDT.

In this study, the tumor-targeted MRI contrast agent was prepared with gelatinase-stimuli nanoparticles (NPs) and Omniscan (Omn) by double emulsion method. The size, distribution, morphology, stability, drug loading, and encapsulation efficiency of Omn-NPs were characterized. The macroscopic and microscopic morphological changes of NPs in response to gelatinases (collagenases IV) were observed. The MR imaging using Omn-NPs as a contrast agent was evaluated in the oral squamous cell carcinoma models with Omn as a control. We found clear evidence that the Omn-NPs were transformed by gelatinases and the signal of T1-weighted MRI sequence showed that the tumor-to-background ratio was significantly higher in Omn-NPs than in Omn. The peak point of time after injection was much later for Omn-NPs than Omn. This study demonstrates that Omn-NPs hold great promise as MRI contrast agent with improved specificity and prolonged circulation time based on a relatively simple and universal strategy.

Doxorubicin (DOX) is an effective chemotherapy drug used to treat many malignancies, including breast cancer. However, its clinical application is severely limited by cardiotoxicity. This study investigated if using thermo/pHsensitive magnetic nanoparticles decorated with folate (folate-poly-MNPs) as tumor-targeted drug delivery systems (DDSs) could reduce the cardiotoxicity and inflammatory properties of DOX in a rat model of breast cancer. In this study, forty rats were intravenously administered the control, DOX, DOX-poly-MNPs, and DOXfolate-poly-MNPs every 48 hours for 12 days. The cardiac health monitoring following breast cancer therapy confirmed that the novel smart DDS improved ECG pattern, left ventricular function, blood pressure parameters, and heart weight index. Moreover, it could decrease myocardial cell death by decreasing the protein levels of BAX, c-PARP1, and c-caspase-3, with concomitant downregulation of the BAX/Bcl-2 ratio, compared to the commercial DOX. In addition, the DOXfolate-poly-MNPs treatment significantly reduced NLRP3 inflammasome activation in cardiomyocytes, which was mediated by caspase-1 inhibition, and suppressed upregulation of IL-1β and IL18 protein expression to prevent myocardial damage. In this regard, the developed folatepolyMNPs could be represented as a new potential drug delivery system for breast cancer chemotherapy due to the combination of passive and active targeting aimed at preventing nonspecific body distribution, inhibiting NLRP3 inflammasome activation, and consequently reducing DOX cardiotoxicity as its main adverse effect.

BackgroundThe costimulatory receptor CD137 (also known as 4-1BB and TNFRSF9) plays an important role in sustaining effective cytotoxic T cell immune responses and its agonism has been investigated as a cancer immunotherapy. In clinical trials, the systemic administration of the 1st generation CD137 agonist monotherapies, utomilumab and urelumab, were suspended due to either low anti-tumor efficacy or hepatotoxicity mediated by recognized epitope on CD137 and FcγR ligand-dependent clustering.MethodsM9657, a bispecific antibody was engineered a tetravalent bispecific antibody (mAb2) format with the Fab portion binding to the tumor antigen Mesothelin (MSLN) and a modified CH2-CH3 domain as Fc antigen binding (Fcab) portion binding to CD137. M9657 has a human IgG1 backbone with LALA mutations to abrogate the binding to Fcγ receptor. The biological characteristics and activities of M9657 were investigated in a series of in vitro assays and the in vivo efficacy was investigated in syngeneic tumor models with FS122m, a murine-reactive surrogate with the same protein structure of M9657.ResultsM9657 binds efficiently to both human and Cynomolgus CD137 as well as MSLN. In the cellular functional assay, M9657 displayed MSLN- and TCR/CD3 interaction (signal 1)-dependent cytokine release and tumor cell cytotoxicity associated with Bcl-XL activation and immune memory formation. FS122m demonstrated potent MSLN- and dose- dependent in vivo anti-tumor efficacy (figure 1). Comparing with 3H3, a Urelumab surrogate Ab, FS122m displayed an improved therapeutic window with significantly lower for on-target /off-tumor toxicity.ConclusionsTaken together, M9657 exhibits a promising developability profile as a tumor-targeted immune agonist with potent anti-cancer activity, but without systemic immune activation.Ethics ApprovalAll animal experiments were performed in accordance with EMD Serono Research & Development Institute (protocol 17-008, 20-005) and Wuxi AppTec Animal Care and Use Committee (IACUC) guidelines.Abstract 757 Figure 1FS122m displayed dose-dependent anti-tumor efficacy

β-cyclodextrin-based star polymers have attracted much interest because of their unique structures and potential biomedical and biological applications. Herein, we synthesized well-defined folic acid (FA)-conjugated and disulfide bond-linked star polymer ((FA-Dex-SS)-βCD-(PCL)14) acted as theranostic nanoparticles for tumor-targeted magnetic resonance imaging (MRI) and chemotherapy. Theranostic nanoparticles were obtained by loading doxorubicin (DOX) and superparamagnetic iron oxide particles (SPIO) were loaded into the star polymer nanoparticles to obtain ((FA-Dex-SS)-βCD-(PCL)14@DOX/SPIO) theranostic nanoparticles. In vitro drug release studies showed that approximately 100% of the DOX was released from disulfide bond-linked theranostic nanoparticles within 24 h under a reducing environment in the presence of 10.0 mM GSH. DOX and SPIO could be delivered into HepG2 cells efficiently, owing to folate receptor-mediated endocytosis process of the nanoparticles and GSH triggered disulfide-bonds cleaving.Moreover, (FA-Dex-SS)-βCD-(PCL)14@DOX/SPIO showed strong MRI contrast enhancement properties. In conclusion, folate-decorated reduction-sensitive star polymeric nanoparticles are a potential theranostic nanoparticle candidate for tumor-targeted MRI and chemotherapy.

Glioma is one of the most malignant primary tumors affecting the brain. The efficacy of therapeutics for glioma is seriously compromised by the restriction of blood-brain barrier (BBB), interstitial tumor pressure of resistance to chemotherapy/radiation, and the inevitable damage to normal brain tissues. Inspired by the natural structure and properties of high-density lipoprotein (HDL), a tumor-penetrating lipoprotein was prepared by the fusion tLyP-1 to apolipoprotein A-I-mimicking peptides (D4F), together with indocyanine green (ICG) incorporation and lipophilic small interfering RNA targeted HIF-1α (siHIF) surface anchor for site-specific photo-gene therapy. tLyP-1 peptide is fused to HDL-surface to facilitate BBB permeability, tumor-homing capacity and -site accumulation of photosensitizer and siRNA. Upon NIR light irradiation, ICG not only served as real-time targeted imaging agent, but also provided toxic reactive oxygen species and local hyperthermia for glioma phototherapy. The HIF‐1α siRNA in this nanoplatform downregulated the hypoxia‐induced HIF‐1α level in tumor microenvironment and enhanced the photodynamic therapy against glioma. These studies demonstrated that the nanoparticles could not only efficiently across BBB and carry the payloads to orthotopic glioma, but also modulate tumor microenvironment, thereby inhibiting tumor growth with biosafety. Overall, this study develops a new multifunctional drug delivery system for glioma theranostic, providing deeper insights into orthotopic brain tumor imaging and treatment.

Despite the recent successes in siRNA therapeutics, targeted delivery beyond the liver remains the major hurdle for the widespread application of siRNA in vivo. Current cationic liposome or polymer-based delivery agents are restricted to the liver and suffer from off-target effect, poor clearance, low serum stability, and high toxicity. In this study, we have genetically engineered a non-cationic tumor-targeted universal siRNA nanocarrier. This protein nanocarrier consists of three function domains: dsRNA binding domain (dsRBD) (from human protein kinase R) for any siRNA binding, 18-histidines for endosome escape, and two RGD peptides at N-and C-termini for targeting tumor and tumor neovasculature. We showed that cloned dual-RGD-dsRBD-18his (dual-RGD) protein protects siRNA against RNases, induces effective siRNA endosomal escape, specific targets on integrin αvβ3 expressing cells in vitro, and homes siRNA to tumor in vivo. The delivered siRNA leads target gene knockdown in the cell lines and tumor xenografts with low toxicity. This multifunctional, biomimetic, charge-neutral siRNA carrier is biodegradable, low toxic, suitable for mass production by fermentation, and serum stable, holding great potential to provide a widely applicable siRNA carrier for tumor-targeted siRNA delivery.

Lycorine (Ly) is a promising natural compound with extensive antitumor activities. However, due to poor aqueous solubility and low bioavailability, the research and development of Ly anticancer drugs has been greatly restricted. Recently, the carrier-free nanoparticles have emerged as an outstanding drug delivery system. In this study, we prepared a DSPE-PEG modifying Ly nanoparticle (DS-Ly NPs) to overcome these drawbacks. We find that compared with Ly, DS-Ly NPs can significantly inhibit cell viability. Meanwhile, DS-Ly NPs treatment results in higher promotion of apoptotic and autophagic capacities, as well as inhibition of migration and invasion. Furthermore, DS-Ly NPs exhibits a better antitumor effect in AOM/DSS induced colorectal tumors and orthotopic hepatocellular tumors than Ly in repression of multiple oncogenic processes, which may benefit from the advantages of carrier-free nanoparticle. Beside, we showed that DS-Ly NPs can prolong the blood circulation time better than Ly. Taken together, these results have demonstrated that carrier-free nanoparticle provides a new therapeutic strategy for treating cancer.

The drug delivery systems (DDSs) introduced in recent years have been wide recognized to greatly evaluate the efficacy of drugs. With the aim to increase drug targeting to tumors as well as decrease the side effect of both drug and drug carriers, this study has developed a hybrid DDS by incorporation zinc based metal-organic framework (Zn-MOF) and folic acid (FA). Moreover, adriamycin (Adr) as a model anticancer drug was loaded into the FA/Zn-MOF nanoparticle. The as-prepared FA/ZnMOF/Adr was expected to serve as a tumor targeting DDS that capable of effectively delivering Adr to cervical tumors. Characterization revealed that FA/Zn-MOF/Adr was nanosized spherical particles with high stability and biocompatibility. Most importantly, the FA/Zn-MOF/Adr could realize positive targeting to FA overexpressed HeLa cells through folate receptor (FR). Therefore, FA/Zn-MOF/Adr resulted enhanced in vitro and in vivo anticancer benefits than than free Adr or FA unmodified Zn-MOF/Adr.

In order to succeed in tumor targeted therapy and Ultrasound (US) imaging of tumors, several nano formulations of perfluorocarbon were demonstrated till date. At the same time, large size distribution and small sonographic period were the major reasons for limiting their application. With the help of l-menthol loaded Au@cerasome particles (LMGC), we have developed a unique theranostic agent in this study. LMGC displayed excellent performance in enhancing the contrast of US imaging, which is because of its controllable and sustained production of l-menthol foams under the irradiation of NIR laser. The LMGC showed an effective photothermal conversion along with low cytotoxicity for localized photothermal removal of tumor cells. The necessary heating required to generate LM bubbles was obtained by near-infrared laser irradiation of LMGC in vitro, this might also result in sustained and significant ultrasound signal improvement. Depending on these outcomes, it is evident that LMGC can be a perfect candidate for developing multiuse nano medicines to combine the therapeutic functions and US imaging for treating cancer.

Chemical reactions that can proceed in living systems while not interfering with native biochemical processes are collectively referred to as bioorthogonal chemistry. Selectivity, efficiency, and aqueous compatibility are three significant characteristics of an ideal bioorthogonal reaction. To date, the specialized bioorthogonal reactions that have been reported include: Cu (I)-catalyzed [3 + 2] azido- alkyne cycloadditions (CuAAC), strain-promoted [3 + 2] azide-alkyne cycloadditions (SPAAC), Staudinger ligation, photo-click 1,3-dipolar cycloadditions, strain-promoted alkyne-nitrone cycloadditions (SPANC), transition metal catalysis (TMC), and inverse electron demand Diels-Alder (IEDDA). These reactions are divided into two subtypes, 1) bond-formation reactions (e.g. CuAAC, SPAAC, photo-click cycloadditions, SPANC), which can be conventionally applied in the chemical biology field for target identification, protein-specific modifications and others; and 2) bond-release reactions (e.g. Staudinger ligation, TMC, and IEDDA), which are emerging as powerful approaches for the study of protein activation and drug discovery. Over the past decade, bioorthogonal chemistry has enabled important compound design features in targeted drug discovery and has expanded biological knowledge on intractable targets. Research groups have also focused on the discovery of reactions with improved biocompatibility and increased reaction rates, which will undoubtably prove essential for future therapeutic development. Herein, we highlight two significant applications of bioorthogonal chemistry to drug discovery, which are tumor-targeted prodrug delivery and activation, and self-assembly of bifunctional molecules. The relevant challenges and opportunities are also discussed.