Neutralizing tumor-promoting inflammation with polypeptide-dexamethasone conjugate for microenvironment modulation and colorectal cancer therapy

Dual depletion of myeloid-derived suppressor cells and tumor cells with self-assembled gemcitabine-celecoxib nano-twin drug for cancer chemoimmunotherapy

Myeloid-derived suppressor cells (MDSCs) have played a significant role in facilitating tumor immune escape and inducing an immunosuppressive tumor microenvironment. Eliminating MDSCs and tumor cells remains a major challenge in cancer immunotherapy. A novel approach has been developed using gemcitabine-celecoxib twin drug-based nano-assembled carrier-free nanoparticles (GEM-CXB NPs) for dual depletion of MDSCs and tumor cells in breast cancer chemoimmunotherapy. The GEM-CXB NPs exhibit prolonged blood circulation, leading to the preferential accumulation and co-release of GEM and CXB in tumors. This promotes synergistic chemotherapeutic activity by the proliferation inhibition and apoptosis induction against 4T1 tumor cells. In addition, it enhances tumor immunogenicity by immunogenic cell death induction and MDSC-induced immunosuppression alleviation through the depletion of MDSCs. These mechanisms synergistically activate the antitumor immune function of cytotoxic T cells and natural killer cells, inhibit the proliferation of regulatory T cells, and promote the M2 to M1 phenotype repolarization of tumor-associated macrophages, considerably enhancing the overall antitumor and anti-metastasis efficacy in BALB/c mice bearing 4T1 tumors. The simplified engineering of GEM-CXB NPs, with their dual depletion strategy targeting immunosuppressive cells and tumor cells, represents an advanced concept in cancer chemoimmunotherapy.

Glucocorticoids-based prodrug design: Current strategies and research progress

Attributing to their broad pharmacological effects encompassing anti-inflammation, antitoxin, and immunosuppression, glucocorticoids (GCs) are extensively utilized in the clinic for the treatment of diverse diseases such as lupus erythematosus, nephritis, arthritis, ulcerative colitis, asthma, keratitis, macular edema, and leukemia. However, long-term use often causes undesirable side effects, including metabolic disorders-induced Cushing's syndrome (buffalo back, full moon face, hyperglycemia, etc.), osteoporosis, aggravated infection, psychosis, glaucoma, and cataract. These notorious side effects seriously compromise patients' quality of life, especially in patients with chronic diseases. Therefore, glucocorticoid-based advanced drug delivery systems for reducing adverse effects have received extensive attention. Among them, prodrugs have the advantages of low investment, low risk, and high success rate, making them a promising strategy. In this review, we propose the strategies for the design and summarize current research progress of glucocorticoid-based prodrugs in recent decades, including polymer-based prodrugs, dendrimer-based prodrugs, antibody-drug conjugates, peptide-drug conjugates, carbohydrate-based prodrugs, aliphatic acid-based prodrugs and so on. Besides, we also raise issues that need to be focused on during the development of glucocorticoid-based prodrugs. This review is expected to be helpful for the research and development of novel GCs and prodrugs.

Orally available dextran-aspirin nanomedicine modulates gut inflammation and microbiota homeostasis for primary colorectal cancer therapy

Reversing the aggravated immunosuppression hence overgrowth of colorectal cancer (CRC) caused by the gut inflammation and microbiota dysbiosis is pivotal for effective CRC therapy and metastasis inhibition. However, the low delivery efficiency and severe dose-limiting off-target toxicities caused by unsatisfied drug delivery systems remain the major obstacles in precisely modulating gut inflammation and microbiota in CRC therapy. Herein, a multifunctional oral dextran-aspirin nanomedicine (P3C-Asp) was utilized for oral treatment of primary CRC, as it could release salicylic acid (SA) while scavenging reactive oxygen species (ROS) and held great potential in modulating gut microbiota with prebiotic (dextran). Oral P3C-Asp retained in CRC tissues for over 12 h and significantly increased SA accumulation in CRC tissues over free aspirin (10.8-fold at 24 h). The enhanced SA accumulation and ROS scavenging of P3C-Asp cooperatively induced more potent inflammation relief over free aspirin, characterized as lower level of cyclooxygenase-2 and immunosuppressive cytokines. Remarkably, P3C-Asp promoted the microbiota homeostasis and notably increased the relative abundance of strengthening systemic anti-cancer immune response associated microbiota, especially lactobacillus and Akkermansia to 6.66- and 103- fold over the control group. Additionally, a demonstrable reduction in pathogens associated microbiota (among 96% to 79%) including Bacteroides could be detected. In line with our findings, inflammation relief along with enhanced abundance of lactobacillus was positively correlated with CRC inhibition. In primary CRC model, P3C-Asp achieved 2.1-fold tumor suppression rate over free aspirin, with an overall tumor suppression rate of 85%. Moreover, P3C-Asp cooperated with αPD-L1 further reduced the tumor weight of each mouse and extended the median survival of mice by 29 days over αPD-L1 alone. This study unravels the synergistic effect of gut inflammation and microbiota modulation in primary CRC treatment, and unlocks an unconventional route for immune regulation in TME with oral nanomedicine.

Anti-inflammatory properties and characterization of water extracts obtained from Callicarpa kwangtungensis Chun using in vitro and in vivo rat models

Callicarpa kwangtungensis Chun (CK) is a common remedy exhibits anti-inflammatory properties and has been used in Chinese herbal formulations, such as KangGongYan tablets. It is the main component of KangGongYan tablets, which has been used to treat chronic cervicitis caused by damp heat, red and white bands, cervical erosion, and bleeding. However, the anti-inflammatory effects of CK water extract remains unknown. This study assessed the anti-inflammatory effects of CK in vivo and in vitro, characterized its main components in the serum of rats and verified the anti-inflammatory effects of serum containing CK. Nitric oxide (NO), tumour necrosis factor α (TNF-α) and interleukin-6 (IL-6) release by RAW264.7 cells was examined by ELISA and Griess reagents. Inflammation-related protein expression in LPS-stimulated RAW264.7 cells was measured by western blotting. Furthermore, rat model of foot swelling induced by λ-carrageenan and a collagen-induced arthritis (CIA) rat model were used to explore the anti-inflammatory effects of CK. The components of CK were characterized by LC-MS, and the effects of CK-containing serum on proinflammatory factors levels and the expression of inflammation-related proteins were examined by ELISA, Griess reagents and Western blotting. CK suppressed IL-6, TNF-α, and NO production, and iNOS protein expression in LPS-stimulated RAW264.7 cells. Mechanistic studies showed that CK inhibited the phosphorylation of ERK, P38 and JNK in the MAPK signaling pathway, promoted the expression of IκBα in the NF-κB signaling pathway, and subsequently inhibited the expression of iNOS, thereby exerting anti-inflammatory effects. Moreover, CK reduced the swelling rates with λ-carrageenan induced foot swelling, and reduced the arthritis score and incidence in the collagen-induced arthritis (CIA) rat model. A total of 68 compounds in CK water extract and 31 components in rat serum after intragastric administration of CK were characterized. Serum pharmacological analysis showed that CK-containing serum suppressed iNOS protein expression and NO, TNF-α, and IL-6 release. CK may be an anti-inflammatory agent with therapeutic potential for acute and chronic inflammatory diseases, especially inflammatory diseases associated with MAPK activation.

H2S-driven chemotherapy and mild photothermal therapy induced mitochondrial reprogramming to promote cuproptosis

The elevated level of hydrogen sulfide (H2S) in colon cancer hinders complete cure with a single therapy. However, excessive H2S also offers a treatment target. A multifunctional cascade bioreactor based on the H2S-responsive mesoporous Cu2Cl(OH)3-loaded hypoxic prodrug tirapazamine (TPZ), in which the outer layer was coated with hyaluronic acid (HA) to form TPZ@Cu2Cl(OH)3-HA (TCuH) nanoparticles (NPs), demonstrated a synergistic antitumor effect through combining the H2S-driven cuproptosis and mild photothermal therapy. The HA coating endowed the NPs with targeting delivery to enhance drug accumulation in the tumor tissue. The presence of both the high level of H2S and the near-infrared II (NIR II) irradiation achieved the in situ generation of photothermic agent copper sulfide (Cu9S8) from the TCuH, followed with the release of TPZ. The depletion of H2S stimulated consumption of oxygen, resulting in hypoxic state and mitochondrial reprogramming. The hypoxic state activated prodrug TPZ to activated TPZ (TPZ-ed) for chemotherapy in turn. Furthermore, the exacerbated hypoxia inhibited the synthesis of adenosine triphosphate, decreasing expression of heat shock proteins and subsequently improving the photothermal therapy. The enriched Cu2+ induced not only cuproptosis by promoting lipoacylated dihydrolipoamide S-acetyltransferase (DLAT) heteromerization but also performed chemodynamic therapy though catalyzing H2O2 to produce highly toxic hydroxyl radicals ·OH. Therefore, the nanoparticles TCuH offer a versatile platform to exert copper-related synergistic antitumor therapy.

Allogeneic "Zombie Cell" as Off-The-Shelf Vaccine for Postsurgical Cancer Immunotherapy

Allogeneic tumor cell vaccines provide off-the-shelf convenience but lack patient specificity due to heterogeneity in tumor antigens. Here, allogeneic tumor cell corpses are converted into "zombie cells" capable of assimilating heterogeneous tumor by seizing cancer cells and spreading adjuvant infection. This causes pseudo-oncolysis of tumors, transforming them into immunogenic targets for enhanced phagocytosis. It is shown that in postoperative tumor models, localized delivery of premade "zombie cells" through stepwise gelation in resection cavity consolidates tumor surgery. Compared to analogous vaccines lacking "seizing" or "assimilating" capability, "zombie cell" platform effectively mobilizes T cell response against residual tumors, and establishes immunological memory against tumor re-challenge, showing less susceptibility to immune evasion. Despite using allogeneic sources, "zombie cell" platform functions as generalizable framework to produce long-term antitumor immunity in different tumor models, showing comparable effect to autologous vaccine. Together, with the potential of off-the-shelf availability and personalized relevance to heterogenous tumor antigens, this study suggests an alternative strategy for timely therapy after tumor surgery.

Engineering Semicarbazide-Bearing Polypeptide Conjugates for Efficient Tumor Chemotherapy and Imaging of Tumor Metastasis

Polypeptide materials offer scalability, biocompatibility, and biodegradability, rendering them an ideal platform for biomedical applications. However, the preparation of polypeptides with specific functional groups, such as semicarbazide moieties, remains challenging. This work reports, for the first time, the straightforward synthesis of well-defined methoxy-terminated poly(ethylene glycol)-b-polypeptide hybrid block copolymers (HBCPs) containing semicarbazide moieties. This synthesis involves implementing the direct polymerization of environment-stable N-phenoxycarbonyl-functionalized α-amino acid (NPCA) precursors, thereby avoiding the handling of labile N-carboxyanhydride (NCA) monomers. The resulting HBCPs containing semicarbazide moieties enable facile functionalization with aldehyde/ketone derivatives, forming pH-cleavable semicarbazone linkages for tailored drug release. Particularly, the intracellular pH-triggered hydrolysis of semicarbazone moieties restores the initial semicarbazide residues, facilitating endo-lysosomal escape and thus improving therapeutic outcomes. Furthermore, the integration of the hypoxic probe (Ir(btpna)(bpy)2 ) into the pH-responsive nanomedicines allows sequential responses to acidic and hypoxic tumor microenvironments, enabling precise detection of metastatic tumors. The innovative approach for designing bespoke functional polypeptides holds promise for advanced drug delivery and precision therapeutics.

Diverse drug delivery systems for the enhancement of cancer immunotherapy: an overview

Despite the clear benefits demonstrated by immunotherapy, there is still an inevitable off-target effect resulting in serious adverse immune reactions. In recent years, the research and development of Drug Delivery System (DDS) has received increased prominence. In decades of development, DDS has demonstrated the ability to deliver drugs in a precisely targeted manner to mitigate side effects and has the advantages of flexible control of drug release, improved pharmacokinetics, and drug distribution. Therefore, we consider that combining cancer immunotherapy with DDS can enhance the anti-tumor ability. In this paper, we provide an overview of the latest drug delivery strategies in cancer immunotherapy and briefly introduce the characteristics of DDS based on nano-carriers (liposomes, polymer nano-micelles, mesoporous silica, extracellular vesicles, etc.) and coupling technology (ADCs, PDCs and targeted protein degradation). Our aim is to show readers a variety of drug delivery platforms under different immune mechanisms, and analyze their advantages and limitations, to provide more superior and accurate targeting strategies for cancer immunotherapy.

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.

Nano-enabled colorectal cancer therapy

Colorectal cancer (CRC), one of the most common and deadliest diseases worldwide, poses a great health threat and social burden. The clinical treatments of CRC encompassing surgery, chemotherapy, and radiotherapy are challenged with toxicity, therapy resistance, and recurrence. In the past two decades, targeted therapy and immunotherapy have greatly improved the therapeutic benefits of CRC patients but they still suffer from drug resistance and low response rates. Very recently, gut microbiota regulation has exhibited a great potential in preventing and treating CRC, as well as in modulating the efficacy and toxicity of chemotherapy and immunotherapy. In this review, we provide a cutting-edge summary of nanomedicine-based treatment in colorectal cancer, highlighting the recent progress of oral and systemic tumor-targeting and/or tumor-activatable drug delivery systems as well as novel therapeutic strategies against CRC, including nano-sensitizing immunotherapy, anti-inflammation, gut microbiota modulation therapy, etc. Finally, the recent endeavors to address therapy resistance, metastasis, and recurrence in CRC were discussed. We hope this review could offer insight into the design and development of nanomedicines for CRC and beyond.

Macrophage-reprogramming upconverting nanoparticles for enhanced TAM-mediated antitumor therapy of hypoxic breast cancer

In an attempt to achieve antitumor effects by switching the phenotype of macrophages from the tumor-promoting M2 type to the tumor-suppressing M1 type, we fabricated mannose-decorated/macrophage membrane-coated, silica-layered NaErF4@NaLuF4 upconverting nanoparticles (UCNPs) co-doped with perfluorocarbon (PFC)/chlorin e6 (Ce6) and loaded with paclitaxel (PTX) (UCNP@mSiO2-PFC/Ce6@RAW-Man/PTX: ∼61 nm; -11.6 mV). These nanoparticles were designed to have two major functionalities, (i) efficient singlet oxygen generation aided by an oxygen supply and (ii) good targeting to tumor-associated macrophage (TAMs) (M2-type), to induce polarization to M1 type macrophages that release proinflammatory cytokines and suppress breast cancers. The primary UCNPs consisted of lanthanide elements (erbium and lutetium) in a core@shell structure, and they facilely emitted 660 nm light in response to a deep-penetrating 808 nm near-infrared laser. Moreover, the UCNPs@mSiO2-PFC/Ce6@RAW-Man/PTX were able to release O2 and generate 1O2 because of the co-doped PFC/Ce6 and upconversion. Our nanocarriers' excellent uptake to RAW 264.7 macrophage cells (M2 type) and efficient M1-type polarization activity were clearly demonstrated using qRT-PCR and immunofluorescence-based confocal laser scanning microscopy. Our nanocarriers displayed significant cytotoxicity to 4T1 cells in 2D culture and 3D co-culture systems of 4T1/RAW 264.7 cells. More importantly, UCNPs@mSiO2-PFC/Ce6@RAW-Man/PTX (+808 nm laser) noticeably suppressed tumor growth in 4T1-xenografted mice, compared with the other treatment groups (332.4 vs. 709.5-1185.5 mm3). We attribute this antitumor efficacy to the prominent M1-type macrophage polarization caused by our nanocarriers through efficient ROS/O2 generation and targeting of M2-type TAMs via mannose ligands on coated macrophage-membrane.

The influence of COVID-19 on colorectal cancer was investigated using bioinformatics and systems biology techniques

Introduction

Coronavirus disease 2019 (COVID-19) is a global pandemic and highly contagious, posing a serious threat to human health. Colorectal cancer (CRC) is a risk factor for COVID-19 infection. Therefore, it is vital to investigate the intrinsic link between these two diseases.

Methods

In this work, bioinformatics and systems biology techniques were used to detect the mutual pathways, molecular biomarkers, and potential drugs between COVID-19 and CRC.

Results

A total of 161 common differentially expressed genes (DEGs) were identified based on the RNA sequencing datasets of the two diseases. Functional analysis was performed using ontology keywords, and pathway analysis was also performed. The common DEGs were further utilized to create a protein-protein interaction (PPI) network and to identify hub genes and key modules. The datasets revealed transcription factors-gene interactions, co-regulatory networks with DEGs-miRNAs of common DEGs, and predicted possible drugs as well. The ten predicted drugs include troglitazone, estradiol, progesterone, calcitriol, genistein, dexamethasone, lucanthone, resveratrol, retinoic acid, phorbol 12-myristate 13-acetate, some of which have been investigated as potential CRC and COVID-19 therapies.

Discussion

By clarifying the relationship between COVID-19 and CRC, we hope to provide novel clues and promising therapeutic drugs to treat these two illnesses.

Synthesis and Characterization of Nanoparticle-Based Dexamethasone-Polypeptide Conjugates as Potential Intravitreal Delivery Systems

The use of dexamethasone for eye disease treatment is limited by its low solubility, bioavailability, and rapid elimination when applied topically. The covalent conjugation of dexamethasone with polymeric carriers is a promising strategy to overcome existing drawbacks. In this work, amphiphilic polypeptides capable of self-assembly into nanoparticles were proposed as potential delivery systems for intravitreal delivery. The nanoparticles were prepared and characterized using poly(L-glutamic acid-co-D-phenylalanine) and poly(L-lysine-co-D/L-phenylalanine) as well as poly(L-lysine-co-D/L-phenylalanine) covered with heparin. The critical association concentration for the polypeptides obtained was in the 4.2-9.4 μg/mL range. The hydrodynamic size of the formed nanoparticles was between 90 and 210 nm, and they had an index of polydispersity between 0.08 and 0.27 and an absolute zeta-potential value between 20 and 45 mV. The ability of nanoparticles to migrate in the vitreous humor was examined using intact porcine vitreous. Conjugation of DEX with polypeptides was performed by additional succinylation of DEX and activation of carboxyl groups introduced to react with primary amines in polypeptides. The structures of all intermediate and final compounds were verified by ¹H NMR spectroscopy. The amount of conjugated DEX can be varied from 6 to 220 µg/mg of polymer. The hydrodynamic diameter of the nanoparticle-based conjugates was increased to 200-370 nm, depending on the polymer sample and drug loading. The release of DEX from the conjugates due to hydrolysis of the ester bond between DEX and the succinyl moiety was studied both in a buffer medium and a vitreous/buffer mixture (50/50, v/v). As expected, the release in the vitreous medium was faster. However, the release rate could be controlled in the range of 96-192 h by varying the polymer composition. In addition, several mathematical models were used to assess the release profiles and figure out how DEX is released.

Nanomedicine-based multimodal therapies: Recent progress and perspectives in colon cancer

Colon cancer has attracted much attention due to its annually increasing incidence. Conventional chemotherapeutic drugs are unsatisfactory in clinical application because of their lack of targeting and severe toxic side effects. In the past decade, nanomedicines with multimodal therapeutic strategies have shown potential for colon cancer because of their enhanced permeability and retention, high accumulation at tumor sites, co-loading with different drugs, and comb-ination of various therapies. This review summarizes the advances in research on various nanomedicine-based therapeutic strategies including chemotherapy, radiotherapy, phototherapy (photothermal therapy and photodynamic therapy), chemodynamic therapy, gas therapy, and immunotherapy. Additionally, the therapeutic mechanisms, limitations, improvements, and future of the above therapies are discussed.

Harnessing Engineered Immune Cells and Bacteria as Drug Carriers for Cancer Immunotherapy

Immunotherapy continues to be in the spotlight of oncology therapy research in the past few years and has been proven to be a promising option to modulate one's innate and adaptive immune systems for cancer treatment. However, the poor delivery efficiency of immune agents, potential off-target toxicity, and nonimmunogenic tumors significantly limit its effectiveness and extensive application. Recently, emerging biomaterial-based drug carriers, including but not limited to immune cells and bacteria, are expected to be potential candidates to break the dilemma of immunotherapy, with their excellent natures of intrinsic tumor tropism and immunomodulatory activity. More than that, the tiny vesicles and physiological components derived from them have similar functions with their source cells due to the inheritance of various surface signal molecules and proteins. Herein, we presented representative examples about the latest advances of biomaterial-based delivery systems employed in cancer immunotherapy, including immune cells, bacteria, and their derivatives. Simultaneously, opportunities and challenges of immune cells and bacteria-based carriers are discussed to provide reference for their future application in cancer immunotherapy.

Environmental Enrichment Protects Offspring of a Rat Model of Preeclampsia from Cognitive Decline

Preeclampsia affects 5-7% of all pregnancies and contributes to adverse pregnancy and birth outcomes. In addition to the short-term effects of preeclampsia, preeclampsia can exert long-term adverse effects on offspring. Numerous studies have demonstrated that offspring of preeclamptic women exhibit cognitive deficits from childhood to old age. However, effective ways to improve the cognitive abilities of these offspring remain to be investigated. The aim of this study was to explore whether environmental enrichment in early life could restore the cognitive ability of the offspring of a rat model of preeclampsia and to investigate the cellular and molecular mechanisms by which EE improves cognitive ability. L-NAME was used to establish a rat model of preeclampsia. The spatial learning and memory abilities and recognition memory of 56-day-old offspring were evaluated by the Morris water maze and Novel object recognition (NOR) task. Immunofluorescence was performed to evaluate cell proliferation and apoptosis in the DG region of the hippocampus. qRT-PCR was performed to examine the expression levels of neurogenesis-associated genes, pre- and postsynaptic proteins and inflammatory cytokines. An enzyme-linked immune absorbent assay was performed to evaluate the concentration of vascular endothelial growth factor (VEGF) and inflammatory cytokines in the hippocampus. The administration of L-NAME led to increased systolic blood pressure and urine protein levels in pregnant rats. Offspring in the L-NAME group exhibited impaired spatial learning ability and memory as well as NOR memory. Hippocampal neurogenesis and synaptic plasticity were impaired in offspring from the L-NAME group. Furthermore, cell apoptosis in the hippocampus was increased in the L-NAME group. The hippocampus was skewed to a proinflammatory profile, as shown by increased inflammatory cytokine levels. EE improved the cognitive ability of offspring in the L-NAME group and resulted in increased hippocampal neurogenesis and synaptic protein expression levels and decreased apoptosis and inflammatory cytokine levels. Environmental enrichment resolves cognitive impairment in the offspring of a rat model of preeclampsia by improving hippocampal neurogenesis and synaptic plasticity and normalizing the apoptosis level and the inflammatory balance.

A Novel Instantaneous Self-Assembled Hollow MOF-Derived Nanodrug for Microwave Thermo-Chemotherapy in Triple-Negative Breast Cancer

Hollow materials derived from metal-organic frameworks (MOFs) have emerged in the biomedical field due to their unique properties, and different synthesis methods have been proposed. However, so far, the large-scale use of hollow MOFs is mostly limited by the timeliness of synthesis methods. Herein, we propose a new ultrasonic aerosol flow strategy for the instantaneous synthesis of a Zr-MOF-derived hollow sphere complex (ZC-HSC) in only one step. Through rapid transient heating, the coordination between metal salts and organic ligands occurs along with prompt evaporation of the solvent. The whole process lasts for only about 21 s, compared with several steps that take hours or even days for conventional synthesis methods. Based on the ZC-HSC, we designed a nanodrug with the functions of manipulating the tumor microenvironment, which can reshape the tumor microenvironment by improving tumor hypoxia and inflammatory microenvironment and promoting antiangiogenic therapy. Combined with microwave thermo-chemotherapy, the nanodrugs effectively treat triple-negative breast cancer (the tumor cell survival rate was only 34.76 and 31.05% in normoxic and hypoxic states, respectively, and the tumor inhibition rate reached 87.9% at the animal level), providing a new theoretical basis for the treatment of triple-negative breast cancer. This rapid, one-step, and continuous ultrasonic aerosol flow strategy has bright prospects in the synthesis of MOF-derived hollow materials and promotes the further development of large-scale applications of biological nanomaterials.

Dual-Modal Imaging and Synergistic Spinal Tumor Therapy Enabled by Hierarchical-Structured Nanofibers with Cascade Release and Postoperative Anti-adhesion

Most treatments for spinal cancer are accompanied by serious side effects including subsequent tumor recurrence, spinal cord compression, and tissue adhesion, thus a highly effective treatment is crucial for preserving spinal and neurological functionalities. Herein, trilayered electrospun doxorubicin@bovine serum albumin/poly(ε-caprolactone)/manganese dioxide (DOX@BSA/PCL/MnO₂) nanofibers with excellent antiadhesion ability, dual glutathione/hydrogen peroxide (GSH/H₂O₂) responsiveness, and cascade release of Mn²⁺/DOX was fabricated for realizing an efficient spinal tumor therapy. In detail, Fenton-like reactions between MnO₂ in the fibers outermost layer and intra-/extracellular glutathione within tumors promoted the first-order release of Mn²⁺. Then, sustained release of DOX from the fibers' core layer occurred along with the infiltration of degradation fluid. Such release behavior avoided toxic side effects of drugs, regulated inflammatory tumor microenvironment, amplified tumor elimination efficiency through synergistic chemo-/chemodynamic therapies, and inhibited recurrence of spinal tumors. More interestingly, magnetic resonance and photoacoustic dual-modal imaging enabled visualizations of tumor therapy and material degradation in vivo, achieving rapid pathological analysis and diagnosis. On the whole, such versatile hierarchical-structured nanofibers provided a reference for rapid and potent theranostic of spinal cancer in future clinical translations.

Regulatory pattern of abnormal promoter CpG island methylation in the glioblastoma multiforme classification

Glioblastoma (GBM) is characterized by extensive genetic and phenotypic heterogeneity. However, it remains unexplored primarily how CpG island methylation abnormalities in promoter mediate glioblastoma typing. First, we presented a multi-omics scale map between glioblastoma sample clusters constructed based on promoter CpG island (PCGI) methylation-driven genes, using datasets including methylation profiles, expression profiles, and single-cell sequencing data from multiple highly annotated public clinical cohorts. Second, we identified differences in the tumor microenvironment between the two glioblastoma sample clusters and resolved key signaling pathways between cell clusters at the single-cell level based on comprehensive comparative analyses to investigate the reasons for survival differences between two of these clusters. Finally, we developed a diagnostic map and a prediction model for glioblastoma, and compared theoretical differences of drug sensitivity between two glioblastoma sample clusters. In summary, this study established a classification system for dissecting promoter CpG island methylation heterogeneity in glioblastoma and provides a new perspective for the diagnosis and treatment of glioblastoma.

Engineered nanomedicines for augmenting the efficacy of colorectal cancer immunotherapy

Colorectal cancer (CRC) is one of the most devastating diseases worldwide. Immunotherapeutic agents for CRC treatment have shown limited efficacy due to the immunosuppressive tumor microenvironment (TME). In this context, various types of nanoparticles (NPs) have been used to reverse the immunosuppressive TME, potentiate the effect of immunotherapeutic agents and reduce their systemic side effects. Many advantages could be offered by NPs, related to drug-loading efficiency, particle size and others that can potentially aid the delivery of immunotherapeutic agents. The recent research on how nano-based immunotherapy can remodel the immunosuppressive TME of CRC and hence boost the antitumor immune response, as well as the challenges that face clinical translation of NPs and future perspectives, are summarized in this review article.

Research Progress of Conjugated Nanomedicine for Cancer Treatment

The conventional cancer therapeutic modalities include surgery, chemotherapy and radiotherapy. Although immunotherapy and targeted therapy are also widely used in cancer treatment, chemotherapy remains the cornerstone of tumor treatment. With the rapid development of nanotechnology, nanomedicine is believed to be an emerging field to further improve the efficacy of chemotherapy. Until now, there are more than 17 kinds of nanomedicine for cancer therapy approved globally. Thereinto, conjugated nanomedicine, as an important type of nanomedicine, can not only possess the targeted delivery of chemotherapeutics with great precision but also achieve controlled drug release to avoid adverse effects. Meanwhile, conjugated nanomedicine provides the platform for combining several different therapeutic approaches (chemotherapy, photothermal therapy, photodynamic therapy, thermodynamic therapy, immunotherapy, etc.) with the purpose of achieving synergistic effects during cancer treatment. Therefore, this review focuses on conjugated nanomedicine and its various applications in synergistic chemotherapy. Additionally, the further perspectives and challenges of the conjugated nanomedicine are also addressed, which clarifies the design direction of a new generation of conjugated nanomedicine and facilitates the translation of them from the bench to the bedside.

Recent Progress in Bio-Responsive Drug Delivery Systems for Tumor Therapy

Spatially- and/or temporally-controlled drug release has always been the pursuit of drug delivery systems (DDSs) to achieve the ideal therapeutic effect. The abnormal pathophysiological characteristics of the tumor microenvironment, including acidosis, overexpression of special enzymes, hypoxia, and high levels of ROS, GSH, and ATP, offer the possibility for the design of stimulus-responsive DDSs for controlled drug release to realize more efficient drug delivery and anti-tumor activity. With the help of these stimulus signals, responsive DDSs can realize controlled drug release more precisely within the local tumor site and decrease the injected dose and systemic toxicity. This review first describes the major pathophysiological characteristics of the tumor microenvironment, and highlights the recent cutting-edge advances in DDSs responding to the tumor pathophysiological environment for cancer therapy. Finally, the challenges and future directions of bio-responsive DDSs are discussed.

Functional cRGD-Conjugated Polymer Prodrug for Targeted Drug Delivery to Liver Cancer Cells

To overcome the limitation of conventional nanodrugs in tumor targeting efficiency, coupling targeting ligands to polymeric nanoparticles can enhance the specific binding of nanodrugs to tumors. Cyclo(Arg-Gly-Asp-d-Phe-Lys) (abbreviated as c(RGDfK)) peptide has been widely adopted due to its high affinity to the tumor marker α_vβ₃ integrin receptor. In this study, we develop a cRGD peptide-conjugated camptothecin (CPT) prodrug, which enables self-assembly of nanoparticles for precise targeting and enrichment in tumor tissue. We first synthesized a camptothecin derivative (CPT-ss-N₃) with a reduction-sensitive bond and simultaneously modified PEG to obtain cRGD-PEG-N₃. After ring-opening polymerization of the 2-(but-3-yn-1-yolxy)-2-oxo-1,3,2-dioxaphospholane (BYP), an amphiphilic polymeric prodrug, referred to as cRGD-PEG-g-(PBYP-ss-CPT), was obtained via copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction. The self-assembly in buffer solution of the cRGD-functional prodrug was studied through DLS and TEM. The in vitro drug release behavior of cRGD-PEG-g-(PBYP-ss-CPT) nanoparticles was investigated. The results show that the nanoparticles are reduction-responsive and the bonded CPT can be released. Endocytosis and MTT assays demonstrate that the cRGD-conjugated prodrug has better affinity for tumor cells, accumulates more intracellularly, and is therefore, more effective. The in vivo drug metabolism studies show that nanoparticles greatly prolong the retention time in circulation. By monitoring drug distribution in tumor and in various tissues, we find that free CPT can be rapidly metabolized, resulting in low accumulation in all tissues. However, cRGD-PEG-g-(PBYP-ss-CPT) nanoparticles accumulate in tumor tissues in higher amounts than PEG-g-(PBYP-ss-CPT) nanoparticles, except for the inevitable capture by the liver. This indicates that the nanomedicine with cRGD has a certain targeting property, which can improve drug delivery efficiency.

Salicylic acid-based hypoxia-responsive chemodynamic nanomedicines boost antitumor immunotherapy by modulating immunosuppressive tumor microenvironment

The delivery of salicylic acid or its derivatives to tumor tissue in the form of nanomedicine is critical for the studies on their potential synergistic mechanism in tumor therapy and chemoprevention considering the dangerous bleeding in the high-dose oral administration. To deepen the understanding of their role in adjusting immunosuppressive tumor microenvironment (ITM), herein, we firstly developed a hypoxia-sensitive Fe-5,5'-azosalicylic acid nanoscale coordination polymer nanomedicines (FeNCPs) via a "old drugs new tricks" strategy for synergistic chemodynamic therapy (CDT) and remodulation of ITM to elevate antitumor immunotherapy effect. PEGylated FeNCPs could be reductively cleaved to release 5-aminosalicylic acid (5-ASA) and ferric ions by azo-reductase under hypoxic conditions, which could induce tumor cell death by Fenton reaction-catalysis enhanced CDT and 5-ASA-converted carboxylquinone to promote the production of •OH. Meanwhile, cyclooxygenase-2 (COX-2) and its enzymatic product prostaglandin E₂ (PGE₂), as immune negative regulatory molecules, can promote tumor progression and immune tolerance. The released 5-ASA as a COX inhibitor could suppress the expression of PGE₂, and Fe³⁺ was employed to reeducate M2-like tumor-associated macrophages (TAMs) to M1-like phenotype, which could initiate antitumor immune response to reach better antitumor immunotherapy. This work broadens the application of salicylic acid derivatives in antitumor immunotherapy, and provides a new strategy for their "old drugs new tricks". STATEMENT OF SIGNIFICANCE: Cyclooxygenase-2 (COX-2) and its enzymatic product prostaglandin E2 (PGE₂), as immune negative regulatory molecules, facilitate the differentiation of immune cells into immunosuppressive cells to build the immunosuppressive tumor microenvironment, which can promote tumor progression and immune tolerance. Thus, down-regulation of COX-2/PGE₂ expression may be a key approach to tumor treatments. Meanwhile, as a class of inhibitors of COX-2/PGE₂, the potential mechanism of aspirin or 5-aminosalicylic acid has been a mystery in tumor therapy and chemoprevention. To expand the application of aspirin family nanomedicine in biomedicine, herein, we firstly developed a hypoxia-sensitive Fe-5,5'-azosalicylic acid nanoscale coordination polymer nanomedicines via a "old drugs new tricks" strategy for synergistic chemodynamic therapy and remodulation of immunosuppressive tumor microenvironment to elevate antitumor immunotherapy effect.

Injectable alginate hydrogels for synergistic tumor combination therapy through repolarization of tumor-associated macrophages

Locally administered drug delivery systems are promising as they allow to circumvent the side effects associated with systematic administration. In this study, we constructed multifunctional hydrogels by simply mixing commercial alginate (ALG) sols with glucose oxidase (GOx)-conjugated polyacrylic acid-stabilized iron oxide nanoparticles (GPI NPs) and Toll-like receptor 7/8 agonist resiquimod (R848). The injectable sols were able to transform into hydrogels (GPI/R848@ALG) by the ionic cross-linking between ALG and physiological Ca²⁺ to trap the therapeutic components within the hydrogel framework. Upon intratumoral injection, the hydrogels were employed for starvation therapy, promoted chemodynamic therapy and tumor-associated macrophages (TAMs) repolarization. The energy supply was blocked by consuming the intratumoral glucose via the GOx-catalyzed conversion of glucose into gluconic acid and hydrogen peroxide (H₂O₂)_.In vitro results showed that the generated H₂O₂ could be further converted into highly cytotoxic hydroxyl radicals (·HO) by the Fenton reaction to induce enhanced chemodynamic therapy. The TAMs repolarization studies in vitro exhibited that the GPI/R848@ALG hydrogels up-regulated the expression of CD86 by 63% and down-regulated the proportion of CD206 by 14% with a synergistic effect of the presence of Fe₃O₄ and R848, suggesting that the multifunctional hydrogels exert functions to direct the remodeling of TAMs from the tumor supportive M2-like phenotype to the tumor destructive M1-like phenotype to further contribute to the antitumor effect. Moreover, both in vitro and in vivo experiments demonstrate that the multifunctional hydrogels exhibit admirable antitumor performance towards 4 T1 tumors. This work thereby provides a promising multifunctional nanoplatform for synergistic cancer starvation therapy, chemodynamic therapy and TAMs repolarization.

Nucleobase-crosslinked poly(2-oxazoline) nanoparticles as paclitaxel carriers with enhanced stability and ultra-high drug loading capacity for breast cancer therapy

Poly(2-oxazoline) (POx) has been regarded as a potential candidate for drug delivery carrier to meet the challenges of nanomedicine clinical translation, due to its excellent biocompatibility and self-assembly properties. The drug loading capacity and stability of amphiphilic POxs as drug nanocarriers, however, tend to be insufficient. Herein, we report a strategy to prepare nucleobase-crosslinked POx nanoparticles (NPs) with enhanced stability and ultra-high paclitaxel (PTX) loading capacity for breast cancer therapy. An amphiphilic amine-functionalized POx (PMBEOx-NH₂) was firstly prepared through a click reaction between cysteamines and vinyl groups in poly(2-methyl-2-oxazoline)-block-poly (2‑butyl‑2-oxazoline-co-2-butenyl-2-oxazoline) (PMBEOx). Complementary nucleobase-pairs adenine (A) and uracil (U) were subsequently conjugated to PMBEOx-NH₂ to give functional POxs (POxA and POxU), respectively. Due to the nucleobase interactions formed between A and U, NPs formed by POxA and POxU at a molar ratio of 1:1 displayed ultrahigh PTX loading capacity (38.2%, PTX/POxA@U), excellent stability, and reduced particle size compared to the uncross-linked PTX-loaded NPs (PTX/PMBEOx). Besides the prolonged blood circulation and enhanced tumor accumulation, the smaller PTX/POxA@U NPs also have better tumor penetration ability compared with PTX/PMBEOx, thus leading to a higher tumor suppression rate in two murine breast cancer models (E0711 and 4T1). These results proved that the therapeutic effect of chemotherapeutic drugs could be improved remarkably through a reasonable optimization of nanocarriers.

Trauma-Responsive Scaffold Synchronizing Oncolysis Immunization and Inflammation Alleviation for Post-Operative Suppression of Cancer Metastasis

Tumor surgery can create an inflammatory trauma to aggravate residual tumor "seed" to colonize pre-metastatic niches (PMNs) "soil" at secondary sites, thereby promoting post-operative metastasis. However, two-pronged strategies for post-surgical elimination of asynchronous "seeds" and "soil" at different regions are currently lacking. Here, we have designed a hydrogel that can be injected into a resection cavity, where it immediately forms a scaffold and gradually degrades responding to enriched reactive oxygen species at adjacent trauma for local delivery and on-demand release of autologous cancer cells succumbing to oncolysis (ACCO) and anti-inflammatory agent. The autologous cell source self-provides a whole array of tumor-associated antigens, and the oncolysis orchestration of a subcellular cascade confers a self-adjuvanting property, together guaranteeing high immunogenicity of the ACCO vaccine that enables specific antitumor immunization. In parallel, inflammation alleviation exerted bidirectional functions to reshape the local immune landscape and resuscitate ACCO, leading to the eradication of residual tumor "seeds" while simultaneously intercepting the "seed-soil" crosstalk to normalize distant lung leading to regression of pre-existing PMN "soil". As a result, regional and metastatic recurrence were completely thwarted. Together, this framework synchronizing oncolysis immunization and inflammation alleviation provides an effective option for post-operative suppression of metastasis.

Ion drugs for precise orthotopic tumor management by in situ the generation of toxic ion and drug pools

Background: Asymmetric intracellular and extracellular ionic gradients are critical to the survivability of mammalian cells. Given the importance of manganese (Mn²⁺), calcium (Ca²⁺), and bicarbonate (HCO₃ ^-) ions, any alteration of the ion-content balance could induce a series of cellular responses. HCO₃ ^- plays an indispensable role for Mn-mediated Fenton-like reaction, but this is difficult to achieve because bicarbonates are tightly regulated by live cells, and are limited in anticancer efficacy. Methods: A responsive and biodegradable biomineral, Mn-doped calcium carbonate integrated with dexamethasone phosphate (DEX) (Mn:CaCO₃-DEX), was reported to enable synergistic amplification of tumor oxidative stress, reduce inflammation, and induce Ca-overload cell apoptosis by elevating the intracellular and extracellular ionic gradients. Results: Under the acidic environment in tumor region, the ions (Mn²⁺, CO₃ ^2-, Ca²⁺) were released by the degradation of Mn:CaCO₃-DEX and then escalated oxidative stresses by triggering a HCO₃ ^--indispensable Mn-based Fenton-like reaction and breaking Ca²⁺ ion homeostasis to cause oxidative stress in cells and calcification. The released anti-inflammatory and antitumor drug, DEX, could alleviate the inflammatory environment. The investigations in vitro and in vivo demonstrated that the synergistic oncotherapy could effectively inhibit the growth of subcutaneous tumors and orthotopic liver tumors. Notably, normal cells showed greater tolerance of the synergistic influences. Conclusion: As an ion drug, Mn:CaCO₃-DEX is an excellent potential diagnostic agent for precise orthotopic tumor management by the generation in situ of toxic ion and drug pools in the environment of tumor region, with synergistic effects of enhanced chemodynamic therapy, calcification, and anti-inflammation effects.

Functional and Therapeutic Significance of Tumor-Associated Macrophages in Colorectal Cancer

The role of the tumor microenvironment (TME) in the progression of colorectal cancer (CRC) and its acquisition of resistance to treatment become the research hotspots. As an important component of TME, the tumor-associated macrophages (TAMs) regulate multiple critical oncogenic processes, namely, occurrence, proliferation, metastasis, and drug resistance in CRC. In this review, we have discussed the functional and therapeutic significance of TAMs in CRC. M1 macrophages act as the tumor suppressor while M2 macrophages promote CRC. The polarization of TAMs is mainly regulated by the pathways such as NFKB1 pathways, STAT3 pathways, WNT5A pathways, and PI3K pathways in CRC. Furthermore, the M2 polarization of TAMs is not only controllable but also reversible. Finally, we provide insights into the TAMs-targeted therapeutic strategies.

Tumor microenvironment-responsive size-switchable drug delivery nanosystems

INTRODUCTION

Compared with ordinary chemotherapeutic drugs, the variable-size nanoparticles (NPs) have better therapeutic effects and fewer side effects.

AREAS COVERED

This review mainly summarizes the strategies used to construct smart, size-tunable nanocarriers based on characteristic factors of tumor microenvironment (TME) to dramatically increase the penetration and retention of drugs within tumors.

EXPERT OPINION

Nanosystems with changeable sizes based on the TME have been extensively studied in the past decade, and their permeability and retention have been greatly improved, making them a very promising treatment for tumors.

Advantages and drawbacks of dexamethasone in glioblastoma multiforme

The most widespread, malignant, and deadliest type of glial tumor is glioblastoma multiforme (GBM). Despite radiation, chemotherapy, and radical surgery, the median survival of afflicted individuals is about 12 months. Unfortunately, existing therapeutic interventions are abysmal. Dexamethasone (Dex), a synthetic glucocorticoid, has been used for many years to treat brain edema and inflammation caused by GBM. Several investigations have recently shown that Dex also exerts antitumoral effects against GBM. On the other hand, more recent disputed findings have questioned the long-held dogma of Dex treatment for GBM. Unfortunately, steroids are associated with various undesirable side effects, including severe immunosuppression and metabolic changes like hyperglycemia, which may impair the survival of GBM patients. Current ideas and concerns about Dex's effects on GBM cerebral edema, cell proliferation, migration, and its clinical outcomes were investigated in this study.

CT imaging findings of renal epithelioid lipid-poor angiomyolipoma

OBJECTIVES

To identify specific imaging and clinicopathological features of a rare potentially malignant epithelioid variant of renal lipid-poor angiomyolipoma (E-lpAML).

METHODS

A total of 20 patients with E-lpAML and 43 patients with other lpAML were retrospectively included. Multiphase computed tomography (CT) imaging features and clinicopathological findings were recorded. Independent predictors for E-lpAML were identified using multivariate logistic regression and were used to construct a diagnostic score for differentiation of E-lpAML from other lpAML.

RESULTS

The E-lpAML group consisted of 6 men and 14 women (age median ± SD: 39.45 ± 15.70, range: 16.0-68.0 years). E-lpAML tended to appear as hyperdense mass lesions located at the renal sinus (n = 8, 40%) or at the renal cortex (n = 12, 60%), with a "fast-in and slow-out" enhancement pattern (n = 20, 100%), cystic degeneration (n = 18, 90%), "eyeball" sign (n = 11, 55%), and tumor neo-vasculature (n = 15, 75%) on CT. Multivariate logistic regression analysis showed that the independent predictors for diagnosing E-lpAML were cystic degeneration on CT imaging and CT value of the tumor in corticomedullary phase of enhancement. A predictive model was built with the two predictors, achieving an area under the curve (AUC) of 93.5% (95% confidence interval (95%CI): 84.3-98.2%) with a sensitivity of 95.0% (95%CI: 75.1-99.9%) and a specificity of 83.72% (95%CI: 69.3-93.2%).

CONCLUSION

We identified specific CT imaging features and predictors that could contribute to the correct diagnosis of E-lpAML. Our findings should be helpful for clinical management of E-lpAML which could potentially be malignant and may require nephron-sparing surgery while other lpAML tumors which are benign require no intervention.

KEY POINTS

• It is important to differentiate renal epithelioid lipid-poor angiomyolipoma (E-lpAML) from other lpAML because of differences in clinical management. • E-lpAML tumors tend to be large hyperdense tumors in the renal sinus with cystic degeneration and "fast-in and slow-out" pattern of enhancement. • Our CT imaging-based predictive model was robust in its performance for predicting E-lpAML from other lpAML tumors.

Nanoparticle-based drug delivery systems in cancer: A focus on inflammatory pathways

It has become necessary to accept the clinical reality of therapeutic agents targeting the cancer-associated immune system. In recent decades, several investigations have highlighted the role of inflammation in cancer development. It has now been recognized that inflammatory cells secrete mediators, including enzymes, chemokines, and cytokines. These secreted substances produce an inflammatory microenvironment that is critically involved in cancer growth. Inflammation may enhance genomic instability leading to DNA damage, activation of oncogenes, or compromised tumor suppressor activity, all of which may promote various phases of carcinogenesis. Conventional cancer treatment includes surgery, radiation, and chemotherapy. However, treatment failure occurs because current strategies are unable to achieve complete local control due to metastasis. Nanoparticles (NPs) are a broad spectrum of drug carriers typically below the size of 100 nm, targeting tumor sites while reducing off-target consequences. More importantly, NPs can stimulate innate and adaptive immune systems in the tumor microenvironment (TME); hence, they induce a cancer-fighting immune response. Strikingly, targeting cancer cells with NPs helps eliminate drug resistance and tumor recurrence, as well as prevents inflammation. Throughout this review, we provide recent data on the role of inflammation in cancer and explore nano-therapeutic initiatives to target significant mediators, for example, nuclear factor-kappa B (NF-κB), tumor necrosis factor-α (TNF-α), and interleukins (ILs) associated with cancer-related inflammation, to escort the immunomodulators to cancer cells and associated systemic compartments. We also highlight the necessity of better identifying inflammatory pathways in cancer pathophysiology to develop effective treatment plans.

Diosgenin From Dioscorea Nipponica Rhizoma Against Graves’ Disease—On Network Pharmacology and Experimental Evaluation

Dioscorea nipponica rhizoma (DNR) is commonly used for the cure of hyperthyroidism resulting from Graves’ disease (GD) or thyroid nodules. However, its therapeutic mechanism remains unclear. This study aimed to utilize network pharmacology integrated molecular docking and experimental verification to reveal the potential pharmacological mechanism of DNR against GD. First, the active componds of DNR were collected from the HERB database and a literature search was conducted. Then, according to multisource database, the predicted genes of DNR and GD were collected to generate networks. The analysis of protein–protein interaction and GO enrichment and KEGG pathway were employed to discover main mechanisms associated with therapeutic targets. Moreover, molecular docking simulation was applied in order to verify the interactions between the drug and target. Finally, our experiments validated the ameliorated effects of diosgenin, the main component of DNR, in terms of phosphorylation deactivation in IGF-1R, which in turn inhibited the phosphorylation and activation of PI3K-AKT and Rap1-MEK signaling pathways, promoting cell apoptosis and GD remission. Our present study provided a foundation for further investigation of the in-depth mechanisms of diosgenin in GD and will provide new scientific evidence for clinical application.

Self-Delivery Janus-Prodrug for Precise Immuno-Chemotherapy of Colitis-Associated Colorectal Cancer

Aromatized thioketal (ATK) linked the immunoregulatory molecule (budesonide, Bud) and the cytotoxic molecule (gemcitabine, Gem) to construct a ROS-activated Janus-prodrug, termed as BAG. Benefiting from the hydrogen bonding, π-π stacking, and other intermolecular interactions, BAG could self-assemble into nanoaggregates (BAG NA) with a well-defined spherical shape and uniform size distribution. Compared to the carrier-based drug delivery system, BAG NA have ultrahigh drug loading content and ROS concentration-dependent drug release. Colitis-associated colorectal cancer (CAC) is a typical disease in which chronic inflammation transforms into tumors. BAG NA can be internalized by colon cancer C26 cells and then triggered by excessive intracellular ROS to release nearly 100% of the drugs. Based on this, BAG NA showed a stronger pro-apoptotic effect than free Bud combined with free Gem. What is gratifying is that orally administered BAG NA can precisely accumulate in the diseased colon tissues of CAC mice induced by AOM/DSS and simultaneously release Bud and Gem. Bud can regulate the tumor immune microenvironment to restore and enhance the cytotoxicity of Gem. Therefore, BAG NA maximizes the synergistic therapeutic effect through co-delivery of Bud and Gem. This work provided a cutting-edge method for constructing self-delivery Janus-prodrug based on ATK and confirmed its potential application in inflammation-related carcinogenesis.

Tumour Microenvironment Stress Promotes the Development of Drug Resistance

Multi-drug resistance (MDR) is a leading cause of cancer-related death, and it continues to be a major barrier to cancer treatment. The tumour microenvironment (TME) has proven to play an essential role in not only cancer progression and metastasis, but also the development of resistance to chemotherapy. Despite the significant advances in the efficacy of anti-cancer therapies, the development of drug resistance remains a major impediment to therapeutic success. This review highlights the interplay between various factors within the TME that collectively initiate or propagate MDR. The key TME-mediated mechanisms of MDR regulation that will be discussed herein include (1) altered metabolic processing and the reactive oxygen species (ROS)-hypoxia inducible factor (HIF) axis; (2) changes in stromal cells; (3) increased cancer cell survival via autophagy and failure of apoptosis; (4) altered drug delivery, uptake, or efflux and (5) the induction of a cancer stem cell (CSC) phenotype. The review also discusses thought-provoking ideas that may assist in overcoming the TME-induced MDR. We conclude that stressors from the TME and exposure to chemotherapeutic agents are strongly linked to the development of MDR in cancer cells. Therefore, there remains a vast area for potential research to further elicit the interplay between factors existing both within and outside the TME. Elucidating the mechanisms within this network is essential for developing new therapeutic strategies that are less prone to failure due to the development of resistance in cancer cells.

Traditional herbal medicine and nanomedicine: Converging disciplines to improve therapeutic efficacy and human health

Traditional herbal medicine (THM), an ancient science, is a gift from nature. For thousands of years, it has helped humans fight diseases and protect life, health, and reproduction. Nanomedicine, a newer discipline has evolved from exploitation of the unique nanoscale morphology and is widely used in diagnosis, imaging, drug delivery, and other biomedical fields. Although THM and nanomedicine differ greatly in time span and discipline dimensions, they are closely related and are even evolving toward integration and convergence. This review begins with the history and latest research progress of THM and nanomedicine, expounding their respective developmental trajectory. It then discusses the overlapping connectivity and relevance of the two fields, including nanoaggregates generated in herbal medicine decoctions, the application of nanotechnology in the delivery and treatment of natural active ingredients, and the influence of physiological regulatory capability of THM on the in vivo fate of nanoparticles. Finally, future development trends, challenges, and research directions are discussed.

A simple and general strategy for postsurgical personalized cancer vaccine therapy based on an injectable dynamic covalent hydrogel

Cancer vaccines artificially stimulate the immune system against cancer and are considered the most promising treatment of cancer. However, the current progress in vaccine research against cancer is still limited and slow, partially due to the difficulties in identifying and obtaining tumor-specific antigens. Considering surgery as the first choice for tumor treatment in most cases, the authors evaluated whether the resected tumor can be directly used as a source of tumor antigens for designing personalized cancer vaccines. Based on this idea, herein, the authors report a dynamic covalent hydrogel-based vaccine (DCHVax) for personalized postsurgical management of tumors. The study uses proteins extracted from the resected tumor as antigens, CpG as the adjuvant, and a multi-armed poly(ethylene glycol) (8-arm PEG)/oxidized dextran (ODEX) dynamically cross-linked hydrogel as the matrix. Subcutaneous injection of DCHVax recruits dendritic cells to the matrix in situ and elicits robust tumor-specific immune responses. Thus, it effectively inhibits the postoperative growth of the residual tumor in several murine tumor models. This simple and personalized method to develop cancer vaccines may be promising in developing clinically relevant strategies for postoperative cancer treatment.

In-Situ-Sprayed Dual-Functional Immunotherapeutic Gel for Colorectal Cancer Postsurgical Treatment

Surgery remains the most preferred treatment options for colorectal cancer (CRC). Paradoxically, local recurrence and distant metastasis are usually accelerated postsurgery as a consequence of local and systemic immunosuppression caused by surgery. Therefore, modulating tumor postoperative immune microenvironment and activating systemic antitumor immunity are necessary supplementaries for CRC therapy. Here, an in-situ-sprayed immunotherapeutic gel loaded with anti-OX40 antibody (iSGels@aOX40) is reported for CRC postsurgical treatment. The iSGel is formed instantly after spraying with strong adhesion ability via crosslinking between tannic acid (TA) and poly(l-glutamic acid)-g-methoxy poly(ethylene glycol)/phenyl boronic acid (PLG-g-mPEG/PBA). TA not only serves as one component of the iSGel but also relieves the postsurgical immunosuppressive microenvironment by inhibiting the activity of cyclo-oxygenase-2 (COX-2). The aOX40 serves as an immune agonistic antibody and is released from the iSGel in a constant manner lasting for over 20 days. In a subcutaneous murine CRC model, the iSGels@aOX40 results in complete inhibition on tumor recurrence. In addition, the cured mice show resistance to tumor re-challenge, suggesting that immune memory effects are established after the iSGels@aOX40 treatment. In an orthotopic CRC peritoneal metastatic model, the iSGels@aOX40 also remarkably inhibits the growth of the abdominal metastatic tumors, suggesting great potential for clinical CRC therapy.

Stimuli-responsive polypeptides for controlled drug delivery

Controlled drug delivery systems, which could release loaded therapeutics upon physicochemical changes imposed by physiological triggers in the desired zone and during the required period of time, offer numerous advantages over traditional drug carriers including enhanced therapeutic effects and reduced toxicity. A polypeptide is a biocompatible and biodegradable polymer, which can be conveniently endowed with stimuli-responsiveness by introducing natural amino acid residues with innate stimuli-responsive characteristics or introducing responsive moieties to its side chains using simple conjugating methods, rendering it an ideal biomedical material for controlled drug delivery. This feature article summarizes our recent work and other relevant studies on the development of polypeptide-based drug delivery systems that respond to single or multiple physiological stimuli (e.g., pH, redox potential, glucose, and hypoxia) for controlled drug delivery applications. The material designs, synthetic strategies, loading and controlled-release mechanisms of drugs, and biomedical applications of these stimuli-responsive polypeptides-based drug delivery systems are elaborated. Finally, the challenges and opportunities in this field are briefly discussed.

Poly(α-l-lysine)-based nanomaterials for versatile biomedical applications: Current advances and perspectives

Poly(α-l-lysine) (PLL) is a class of water-soluble, cationic biopolymer composed of α-l-lysine structural units. The previous decade witnessed tremendous progress in the synthesis and biomedical applications of PLL and its composites. PLL-based polymers and copolymers, till date, have been extensively explored in the contexts such as antibacterial agents, gene/drug/protein delivery systems, bio-sensing, bio-imaging, and tissue engineering. This review aims to summarize the recent advances in PLL-based nanomaterials in these biomedical fields over the last decade. The review first describes the synthesis of PLL and its derivatives, followed by the main text of their recent biomedical applications and translational studies. Finally, the challenges and perspectives of PLL-based nanomaterials in biomedical fields are addressed.

Targeting Myeloid-Derived Suppressor Cells for Premetastatic Niche Disruption After Tumor Resection

Surgical resection is a common therapeutic option for primary solid tumors. However, high cancer recurrence and metastatic rates after resection are the main cause of cancer related mortalities. This implies the existence of a "fertile soil" following surgery that facilitates colonization by circulating cancer cells. Myeloid-derived suppressor cells (MDSCs) are essential for premetastatic niche formation, and may persist in distant organs for up to 2 weeks after surgery. These postsurgical persistent lung MDSCs exhibit stronger immunosuppression compared with presurgical MDSCs, suggesting that surgery enhances MDSC function. Surgical stress and trauma trigger the secretion of systemic inflammatory cytokines, which enhance MDSC mobilization and proliferation. Additionally, damage associated molecular patterns (DAMPs) directly activate MDSCs through pattern recognition receptor-mediated signals. Surgery also increases vascular permeability, induces an increase in lysyl oxidase and extracellular matrix remodeling in lungs, that enhances MDSC mobilization. Postsurgical therapies that inhibit the induction of premetastatic niches by MDSCs promote the long-term survival of patients. Cyclooxygenase-2 inhibitors and β-blockade, or their combination, may minimize the impact of surgical stress on MDSCs. Anti-DAMPs and associated inflammatory signaling inhibitors also are potential therapies. Existing therapies under tumor-bearing conditions, such as MDSCs depletion with low-dose chemotherapy or tyrosine kinase inhibitors, MDSCs differentiation using all-trans retinoic acid, and STAT3 inhibition merit clinical evaluation during the perioperative period. In addition, combining low-dose epigenetic drugs with chemokine receptors, reversing immunosuppression through the Enhanced Recovery After Surgery protocol, repairing vascular leakage, or inhibiting extracellular matrix remodeling also may enhance the long-term survival of curative resection patients.

Diagnostic and prognostic value of tumor-infiltrating B cells in lymph node metastases of papillary thyroid carcinoma

Lymph node metastases are strongly associated with unfavorable prognosis in papillary thyroid carcinoma (PTC) patients. However, there are few sensitive or specific indicators that can diagnose or predict lymph node metastases in PTC. The objective of our study was to identify reliable indicators for the diagnosis and prediction of lymph node metastases of PTC. The PTC data set was obtained from The Cancer Genome Atlas (TCGA) cohort. Information on tumor-infiltrating immune cells in PTC was acquired using single-sample gene set enrichment analysis (ssGSEA). Then, the progression-free survival (PFS) rates of PTC patients were evaluated by Kaplan-Meier curves. A tissue microarray including 58 normal thyroid tissues and 57 PTC tissues was processed for CD19 immunohistochemistry staining. Finally, evaluation of phenotype permutations was performed using gene set enrichment analysis (GSEA). There was an appreciable association between immune infiltration and lymph node metastases in PTC. Among those immune cells, B cells and cytotoxic cells showed significant predictive accuracy for lymph node metastases in PTC. Tumor-infiltrating B cells and NK cells were associated with favorable prognosis, while tumor-associated NK CD56^bright cells were correlated with poor prognosis in PTC patients. IHC analyses of PTC further confirmed a notably negative correlation between B cell infiltration and lymph node metastases in PTC. Additionally, mutations in BRAF, a dominant cause of tumor mutation burden (TMB), were positively correlated with reduced B cell infiltration and lymph node metastases in PTC. GSEA revealed that epithelial-mesenchymal transition, IL-6/JAK/STAT3 signaling, the inflammatory response, and TNF-α signaling via the NFκB pathway were remarkably suppressed pathways in patients with BRAF mutations. Tumor-associated lymphocytic infiltration, especially B cell infiltration, provides diagnostic and prognostic value for lymph node metastases in PTC.

A near-infrared light-excitable immunomodulating nano-photosensitizer for effective photoimmunotherapy

Photodynamic therapy has great potential for tumor ablation and the activation of antitumor immune responses. However, its overall therapeutic efficiency is often limited by the immunosuppressive tumor microenvironment. We developed a near-infrared light-excitable immunomodulating nano-photosensitizer (NeINP) that can improve reactive oxygen species production and regulate the immunosuppressive TME to improve photoimmunotherapy. The NeINP is composed of a photosensitive core and a pH-responsive polymer shell, which allows for NeINP loading and delivery of small-molecular immunomodulators to tumor sites for regulation of the immunosuppressive TME and effective photoimmunotherapy. Through the co-delivery of celecoxib and the NIR-triggered photodynamic core to tumors, the NeINP was shown to regulate the immunosuppressive TME and enhance antitumor immunity, leading to the elimination of residual tumor and reduction of metastasis and recurrence. The NeINP can be optimized to co-deliver other immunomodulators, and thus has potential as a universal platform for efficient, precise photoimmunotherapy.

Combination of preoperative red cell distribution width and neutrophil to lymphocyte ratio as a prognostic marker for gastric cancer patients

Background

The neutrophil to lymphocyte ratio (NLR) and red blood cell distribution width (RDW) play an important role in the prognosis of several cancers, but their prognostic value in patients with stage II-III gastric cancer (GC) is unclear. We aimed to evaluate the prognostic value of the RDW-NLR (R-NLR) score based on RDW and NLR in stage II-III GC patients after radical surgery.

Methods

Preoperative RDW and NLR clinicopathological data were retrospectively reviewed and analyzed from stage II-III GC patients who underwent radical gastrectomy. The optimal cut-off values for pre-RDW-variation coefficient (pre-RDW-cv) and pre-NLR were defined as 14.10% and 2.015, respectively. The R-NLR score was defined as 2 (both elevated RDW and NLR), 1 (one of these was elevated), or 0 (neither were elevated). Prognostic factors were identified by univariate and multivariate analyses.

Results

A total of 151 patients were included in this study, and 65 (43.05%), 54 (35.76%), and 32 (21.19%) patients had an R-NLR score of 0, 1 and 2, respectively. The preoperative R-NLR score was significantly correlated with tumor size and gender (all P<0.05). The 5-year overall survival (OS) in the R-NLR 0, 1, and 2 groups was 52.30%, 44.40%, and 31.20%, respectively (P=0.031), while the 5-year DFS was 47.70%, 13.30%, and 18.80%, respectively (P<0.001). Further, while the 5-year disease-free survival (DFS) rate was significantly improved in low RDW-cv and NLR patients compared with those with high RDW-cv and NLR (all P<0.05), but not OS (all P>0.05). Multivariate analysis demonstrated that the R-NLR score was independently correlated with OS [hazard ratio (HR), 1.527; P=0.007] and DFS (HR, 1.939; P=0.001).

Conclusions

We validated the preoperative R-NLR score to be a promising predictor for stage II-III GC patients who have undergone radical gastrectomy.

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.