In Vivo Environment-Adaptive Nanocomplex with Tumor Cell-Specific Cytotoxicity Enhances T Cells Infiltration and Improves Cancer Therapy

Tumor-infiltrating macrophage associated lncRNA signature in cutaneous melanoma: implications for diagnosis, prognosis, and immunotherapy

Along with the increasing knowledge of long noncoding RNA, the interaction between the long noncoding RNA (lncRNA) and tumor immune infiltration is increasingly valued. However, there is a lack of understanding of correlation between regulation of specific lncRNAs and tumor-infiltrating macrophages within melanoma. In this research, a macrophage associated lncRNA signature was identified by multiple machine learning algorithms and the robust and effectiveness of signature also validated in other independent datasets. The signature contained six specific lncRNAs (PART1, LINC00968, LINC00954, LINC00944, LINC00518 and C20orf197) was constructed, which could diagnose melanoma and predict the prognosis of patients. Moreover, our signature achieves higher accuracy than the previous well-established markers and regarded as an independent prognostic indicator. The pathway enrichment revealed that these lncRNAs were closely correlated with many immune processes. In addition, the signature was associated with different immune microenvironment and applied to predict response of immune checkpoint inhibitor therapy (low risk of patients well respond to anti-PD-1 therapy and high risk is insensitive to anti-CTLA-4 therapy). Therefore, our finding supplies a more accuracy and effective lncRNA signature for tumor-infiltrating macrophages targeting treatment approaches and affords a new clinical application for predicting the response of immunotherapies in melanomas.

A cascade nanoplatform for intelligent response to tumor microenvironment and collaborative cancer therapy

Disulfiram (DSF), a new potential anticancer drug, has been shown to exhibit anticancer activity dependent on the formation of CuET, the chelation product of DSF with Cu2+. However, the poor stability of DSF and insufficient physiological concentration of Cu2+ hinder its practical application. To achieve the co-delivery of DSF and Cu2+ while overcoming the inefficiency of single chemotherapy, in this study, a cascade nanoplatform, DSF/Ce6@ZIF-8@CuO2, was constructed by encapsulating DSF and chlorin e6 (Ce6, a photosensitizer) in zeolite imidazole framework-8 (ZIF-8, a nanocarrier) and then loading CuO2, which self-supplied H2O2/O2, onto DSF/Ce6@ZIF-8. By triggering the response of DSF/Ce6@ZIF-8@CuO2 to the acidic tumor microenvironment, encapsulated DSF, Ce6 and CuO2 were released to achieve multimodal synergistic treatment with enhanced DSF chemotherapy and chemodynamic/photodynamic therapy (CDT/PDT). In vitro and animal studies indicated that the designed DSF/Ce6@ZIF-8@CuO2 has strong tumor-inhibitory effects and provides a promising paradigm for designing smart nanoplatforms.

Meta-Analysis of Nanoparticle Distribution in Tumors and Major Organs in Tumor-Bearing Mice

Low tumor delivery efficiency is a critical barrier in cancer nanomedicine. This study reports an updated version of "Nano-Tumor Database", which increases the number of time-dependent concentration data sets for different nanoparticles (NPs) in tumors from the previous version of 376 data sets with 1732 data points from 200 studies to the current version of 534 data sets with 2345 data points from 297 studies published from 2005 to 2021. Additionally, the current database includes 1972 data sets for five major organs (i.e., liver, spleen, lung, heart, and kidney) with a total of 8461 concentration data points. Tumor delivery and organ distribution are calculated using three pharmacokinetic parameters, including delivery efficiency, maximum concentration, and distribution coefficient. The median tumor delivery efficiency is 0.67% injected dose (ID), which is low but is consistent with previous studies. Employing the best regression model for tumor delivery efficiency, we generate hypothetical scenarios with different combinations of NP factors that may lead to a higher delivery efficiency of >3%ID, which requires further experimentation to confirm. In healthy organs, the highest NP accumulation is in the liver (10.69%ID/g), followed by the spleen 6.93%ID/g and the kidney 3.22%ID/g. Our perspective on how to facilitate NP design and clinical translation is presented. This study reports a substantially expanded "Nano-Tumor Database" and several statistical models that may help nanomedicine design in the future.

Aspirin-Loaded Cross-Linked Lipoic Acid Nanodrug Prevents Postoperative Tumor Recurrence by Residual Cancer Cell Killing and Inflammatory Microenvironment Improvement

In addition to residual cancer cells, the surgery resection-induced hyperinflammatory microenvironment is a key factor that leads to postsurgical cancer recurrence. Herein, we developed a dual-functional nanodrug Asp@cLANVs for postsurgical recurrence inhibition by loading the classical anti-inflammatory drug aspirin (Asp) into cross-linked lipoic acid nanovesicles (cLANVs). The Asp@cLANVs can not only kill residual cancer cells at the doses comparable to common cytotoxic drugs by synergistic interaction between Asp and cLANVs, but also improve the postsurgical inflammatory microenvironment by their strongly synergistic anti-inflammation activity between Asp and cLANVs. Using mice bearing partially removed NCI-H460 tumors, we found that Asp@cLANVs gave a much lower recurrence rate (33.3%) compared with the first-line cytotoxic drug cisplatin (100%), and no mice died for at least 60 days after Asp@cLANV treatment while no mouse survived beyond day 43 in the cisplatin group. This dual-functional nanodrug constructs the first example that combines residual cancer cell killing and postoperative inflammation microenvironment improvement to suppress postsurgical cancer recurrence.

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.

mPEG-PDLLA Micelles Potentiate Docetaxel for Intraperitoneal Chemotherapy in Ovarian Cancer Peritoneal Metastasis

Ovarian cancer is the second most common cause of gynecological cancer death in women. It is usually diagnosed late and accompanied by peritoneal metastasis. For ovarian cancer with peritoneal metastasis, intraperitoneal (IP) chemotherapy can maintain a high drug concentration in the abdominal cavity and reduce local and systemic toxicity. Recently, docetaxel (DTX) has shown broad-spectrum antitumor activity against various malignant tumors, including ovarian cancer with peritoneal metastasis. However, DTX has limited clinical applications due to its poor water solubility, predisposition to hypersensitivity, fluid retention, and varying degrees of neurotoxicity. In this study, we prepared methoxy-poly(ethylene glycol)-block-poly(D,L-lactide) (mPEG-PDLLA) micelles loaded with DTX and developed an alternative, less toxic, more effective DTX formulation, without Tween 80, and evaluated its pharmacokinetics in the abdominal cavity and its efficacy in ovarian cancer with peritoneal metastasis. The mean diameter of DTX-mPEG-PDLLA was about 25 nm, and the pharmacokinetics of BALB/c mice via IP showed that the plasma exposure of DTX-mPEG-PDLLA was about four times lower than that of DTX. Importantly, DTX-mPEG-PDLLA was significantly more effective than DTX and prolonged the survival period in a SKOV-3 ovarian cancer peritoneal metastasis model. Moreover, the apoptosis rate was significantly increased in vitro. Based on these findings, it is expected that DTX-mPEG-PDLLA can enhance efficacy against ovarian cancer peritoneal metastasis, while reducing toxic side effects, and has the potential to be used in the clinical treatment of peritoneal metastatic cancer.

MMP-responsive transformation nanomaterials with IAP antagonist to boost immune checkpoint therapy

The clinical effect of immune checkpoint therapy is limited by the poor blocking efficiency of immune checkpoints and the insufficient infiltration of tumor-specific T cells. Here, we constructed enzyme-responsive PVA-peptide conjugates (PPCs) to achieve re-assembly with enhanced accumulation in the tumor region, enable enhanced PD-L1 occupancy and improve the blocking efficiency. The self-assembled PPC-1 nanoparticles can enter tumor environment, whereas the enzyme-cleavable peptide was digested under overgenerated matrix metalloproteinases (MMP). The accumulated PPC-1 simultaneously transformed into β-sheet fibrous structures around the solid tumor and remained stable for over 96 h, which led to efficiently interrupting the PD-1/PD-L1 interaction. Upon introduction of the IAP antagonists, the non-classical NF-κB pathway of dendritic cells was activated and increased the infiltration of T cells in tumors. With the synergistic contribution of IAP antagonists from the substantial increase in expression of chemokines (CCL5 and CXCL9) and adequate T-cell infiltration in tumor sites, PPC-1 improved the biodistribution and accumulation of PD-L1 antagonists in tumor regions ultimately realizing higher-performance (P < 0.01) tumor growth inhibition efficiency (~80%) than PPC-2 group (~58%) in B16F10 tumor-bearing mice. The growth of the second tumor at the distal end was obviously inhibited (P < 0.01) after the resection of the primary tumor. The combined efficacy was similar to that observed in a Pan02 pancreatic cancer tumor model. This strategy aims to offer novel perspective for the development of locational assembly platforms in vivo and the optimal design of immune checkpoint combination therapy.

Smart Tumor Microenvironment-Responsive Nano-Prodrug for Disulfiram Toxification In Situ and the Exploration of Lethal Mechanisms in Cells

Disulfiram (DSF) is a clinical antialcoholism drug that has been confirmed to show anticancer bioactivity after chelating with Cu²⁺. Therefore, how to co-deliver DSF and Cu²⁺ to tumor tissues and generate a smart response to the tumor microenvironment (TME) are the focus of repurposing DSF for the effective treatment of cancer. Herein, we fabricated facilely a smart nanosystem by coating tannic acid (TA) and Cu²⁺ network on DSF, denoted as DSF@TA-Cu, which responses well to TME and forms CuET complex in situ. In such a way, besides the chemotherapy effect of CuET, the anticancer efficacy of the resulting nano-prodrug can further be augmented by a continuous Fenton-like reaction. We then tested the cytotoxicity DSF@TA-Cu with normal and cancerous cell lines. Finally, by constructing mitochondria-targeted nanoprobes, we monitored the changes in mitochondrial metabolism and explored the lethal mechanisms in A549 cells. We found that DSF@TA-Cu showed higher toxicity to cancerous cells. By analyzing the fluorescence images and surface-enhanced Raman scattering (SERS) spectra of mitochondria, we found that the DNA damage and the decrease in mitochondrial membrane potential (MMP) were closely related to the generation and accumulation of reactive oxygen species (ROS). Although activated related pathways try to counteract the effects of elevation of ROS, excessive ROS inevitably leads to apoptosis of cancer cells.

Nano drug delivery systems improve metastatic breast cancer therapy

Despite continual progress in the technologies and regimens for cancer therapy, the treatment outcome of fatal metastatic breast cancer is far from satisfactory. Encouragingly, nanotechnology has emerged as a valuable tool to optimize drug delivery process in cancer therapy via preventing the cargos from degradation, improving the tumor-targeting efficiency, enhancing therapeutic agents' retention in specific sites, and controlling drug release. In the last decade, several mechanisms of suppressing tumor metastasis by functional nano drug delivery systems (NDDSs) have been revealed and a guidance for the rational design of anti-metastasis NDDSs is summarized, which consist of three aspects: optimization of physiochemical properties, tumor microenvironment remodeling, and biomimetic strategies. A series of medicinal functional biomaterials and anti-metastatic breast cancer NDDSs constructed by our team are introduced in this review. It is hoped that better anti-metastasis strategies can be inspired and applied in clinic.

Smart Nanotherapeutics and Lung Cancer

Lung cancer is a significant health problem worldwide. Unfortunately, current therapeutic strategies lack a sufficient level of specificity and can harm adjacent healthy cells. Consequently, to address the clinical need, novel approaches to improve treatment efficiency with minimal side effects are required. Nanotechnology can substantially contribute to the generation of differentiated products and improve patient outcomes. Evidence from previous research suggests that nanotechnology-based drug delivery systems could provide a promising platform for the targeted delivery of traditional chemotherapeutic drugs and novel small molecule therapeutic agents to treat lung cancer cells more effectively. This has also been found to improve the therapeutic index and reduce the required drug dose. Nanodrug delivery systems also provide precise control over drug release, resulting in reduced toxic side effects, controlled biodistribution, and accelerated effects or responses. This review highlights the most advanced and novel nanotechnology-based strategies, including targeted nanodrug delivery systems, stimuli-responsive nanoparticles, and bio-nanocarriers, which have recently been employed in preclinical and clinical investigations to overcome the current challenges in lung cancer treatments.

Advances of nanomedicines in breast cancer metastasis treatment targeting different metastatic stages

Breast cancer is the most common tumor in women, and the metastasis further increases the malignancy with extremely high mortality. However, there is almost no effective method in the clinic to completely inhibit breast cancer metastasis due to the dynamic multistep process with complex pathways and scattered occurring site. Nowadays, nanomedicines have been evidenced with great potential in treating cancer metastasis. In this review, we summarize the latest research advances of nanomedicines in anti-metastasis treatment. Strategies are categorized according to the metastasis dynamics, including primary tumor, circulating tumor cells, pre-metastatic niches and secondary tumor. In each different stage of metastasis process, nanomedicines are designed specifically with different functions. At the end of the review, we give our perspectives on current limitations and future directions in anti-metastasis therapy. We expect the review provides comprehensive understandings of anti-metastasis therapy for breast cancer, and boosts the clinical translation in the future to improve women's health.

Aspirin inhibits tumor progression and enhances cisplatin sensitivity in epithelial ovarian cancer

Background

Ovarian cancer is the most common gynecological malignancy and is difficult to manage due to the emergence of resistance to various chemotherapeutic drugs. New efforts are urgently awaited. Aspirin, which is traditionally considered a nonsteroidal anti-inflammatory drug (NSAID), has been reported to exert potential chemopreventive effects. Therefore, we aimed to investigate the anticancer effect and explore the underlying molecular mechanisms of aspirin on epithelial ovarian cancer (EOC) cells.

Methods

We conducted wound healing, transwell migration, EdU cell proliferation, colony formation and apoptosis detection assays to observe the effects of aspirin on the migration, proliferation and apoptosis of EOC cells (A2870, Caov-3, and SK-OV-3). EOC cells were treated with a combination of aspirin and cisplatin (CDDP) to observe the effect of aspirin on enhancing CDDP sensitivity. Orthotopic xenograft models of ovarian cancer established with A2780-Luciferase-GFP cells were applied to compare tumor growth inhibition in the control, CDDP and CDDP plus aspirin groups through in vivo imaging, which can be used to continuously monitor tumor growth. The expression and acetylation levels of p53 in EOC cells treated with aspirin were determined using western blotting, and p53 acetylation levels were examined in tumors harvested from the transplanted mice. Quantitative real-time PCR was used to assess the mRNA expression of p53 target genes.

Results

Aspirin inhibited migration and proliferation and induced apoptosis in EOC cell lines in a concentration-dependent manner. In vitro, aspirin enhanced the sensitivity of EOC cells to CDDP by increasing its inhibitory effect on proliferation and its effect on inducing apoptosis. In vivo, the differences in the tumor growth inhibition rates among the different CDDP experimental groups were statistically significant (p < 0.05). Aspirin did not affect p53 protein expression but increased the p53 acetylation level in a concentration-dependent manner. In addition, the mRNA levels of CDKN1A, BAX, FOXF1, PUMA, and RRAD in EOC cells were significantly increased by the aspirin treatment.

Conclusions

Aspirin inhibits tumor progression and enhances the CDDP sensitivity of EOC cells. These antitumor effects of aspirin might be mediated by p53 acetylation and subsequent activation of p53 target genes.

Effects of polyethylene glycol on the surface of nanoparticles for targeted drug delivery

The rapid development of drug nanocarriers has benefited from the surface hydrophilic polymers of particles, which has improved the pharmacokinetics of the drugs. Polyethylene glycol (PEG) is a kind of polymeric material with unique hydrophilicity and electrical neutrality. PEG coating is a crucial factor to improve the biophysical and chemical properties of nanoparticles and is widely studied. Protein adherence and macrophage removal are effectively relieved due to the existence of PEG on the particles. This review discusses the PEGylation methods of nanoparticles and related techniques that have been used to detect the PEG coverage density and thickness on the surface of the nanoparticles in recent years. The molecular weight (MW) and coverage density of the PEG coating on the surface of nanoparticles are then described to explain the effects on the biophysical and chemical properties of nanoparticles.

Emerging nanotaxanes for cancer therapy

The clinical application of taxane (including paclitaxel, docetaxel, and cabazitaxel)-based formulations is significantly impeded by their off-target distribution, unsatisfactory release, and acquired resistance/metastasis. Recent decades have witnessed a dramatic progress in the development of high-efficiency, low-toxicity nanotaxanes via the use of novel biomaterials and nanoparticulate drug delivery systems (nano-DDSs). Thus, in this review, the achievements of nanotaxanes-targeted delivery and stimuli-responsive nano-DDSs-in preclinical or clinical trials have been outlined. Then, emerging nanotherapeutics against tumor resistance and metastasis have been overviewed, with a particular emphasis on synergistic therapy strategies (e.g., combination with surgery, chemotherapy, radiotherapy, biotherapy, immunotherapy, gas therapy, phototherapy, and multitherapy). Finally, the latest oral nanotaxanes have been briefly discussed.

Glycosaminoglycans: Carriers and Targets for Tailored Anti-Cancer Therapy

The tumor microenvironment (TME) is composed of cancerous, non-cancerous, stromal, and immune cells that are surrounded by the components of the extracellular matrix (ECM). Glycosaminoglycans (GAGs), natural biomacromolecules, essential ECM, and cell membrane components are extensively altered in cancer tissues. During disease progression, the GAG fine structure changes in a manner associated with disease evolution. Thus, changes in the GAG sulfation pattern are immediately correlated to malignant transformation. Their molecular weight, distribution, composition, and fine modifications, including sulfation, exhibit distinct alterations during cancer development. GAGs and GAG-based molecules, due to their unique properties, are suggested as promising effectors for anticancer therapy. Considering their participation in tumorigenesis, their utilization in drug development has been the focus of both industry and academic research efforts. These efforts have been developing in two main directions; (i) utilizing GAGs as targets of therapeutic strategies and (ii) employing GAGs specificity and excellent physicochemical properties for targeted delivery of cancer therapeutics. This review will comprehensively discuss recent developments and the broad potential of GAG utilization for cancer therapy.

DNA hydrogel-based gene editing and drug delivery systems

Deoxyribonucleic acid (DNA) is a promising synthesizer for precisely constructing almost arbitrary geometry in two and three dimensions. Among various DNA-based soft materials, DNA hydrogels are comprised of hydrophilic polymeric networks of crosslinked DNA chains. For their properties of biocompatibility, porosity, sequence programmability and tunable multifunctionality, DNA hydrogels have been widely studied in bioanalysis and biomedicine. In this review, recent developments in DNA hydrogels and their applications in drug delivery systems are highlighted. First, physical and chemical crosslinking methods for constructing DNA hydrogels are introduced. Subsequently, responses of DNA hydrogels to nonbiological and biological stimuli are described. Finally, DNA hydrogel-based delivery platforms for different types of drugs are detailed. With the emergence of gene therapy, this review also gives future prospects for combining DNA hydrogels with the gene editing toolbox.

Magnetic nanoparticles coated with polyphenols for spatio-temporally controlled cancer photothermal/immunotherapy

As the combination of photothermal therapy (PTT) with immunotherapy provides an effective strategy in cancer treatment, a magnetic nanoparticle delivery system was constructed to load indocyanine green (ICG) and immunostimulator R837 hydrochloride (R837) for spatio-temporally PTT/immunotherapy synergism in cancer. This delivery system is composed of Fe₃O₄ magnetic nanoparticles (MPs) as the core to load ICG and polyethylene glycol polyphenols (DPA-PEG) as the coating layer to load R837, which formed R837 loaded polyphenols coating ICG loaded magnetic nanoparticles (MIRDs). After intravenous injection, the formed MIRDs resulted in long circulation, magnetic resonance imaging (MRI) guides, and magnetic targeting. Once targeting to the tumor, the MIRDs with the near-infrared (NIR) irradiation caused tumor ablation and resulted in tumor-associated antigens releasing to induce the body's immunological response, which was markedly improved it to attack the tumors with the R837 releasing from the outer DPA-PEG. In this case, the synergism of the PTT and immunotherapy inhibited tumor growth, metastasis and recurrence, which resulted in potent anticancer therapeutic effects with few side effect.