CD44 targeted delivery of siRNA by using HA-decorated nanotechnologies for KRAS silencing in cancer treatment

Intelligent micelles for on-demand drug delivery targeting extracellular matrix of pancreatic cancer

As a key pathological feature of pancreatic ductal adenocarcinoma(PDAC), the dense extracellular matrix(ECM) limits the penetration of chemotherapy drugs and is involved in the formation of immunosuppressive microenvironment. Meanwhile, clinical practice has shown that the treatment strategy for ECM should consider its restriction of tumor cell metastasis, and the need for in-depth chemotherapy without destroying ECM is proposed. STAT3 inhibitors have been reported to regulate tumor microenvironment including interrupt the form of ECM. Therefore, we designed and established a micelle system MP@HA with in vivo targeting and responsive drug release function co-loading gemcitabine monophosphate and STAT3 inhibitor silibinin. The hyaluronic acid on the surface of the micelle can bind specifically to the CD44 molecule on the surface of tumor cells and help micelles accumulate at the tumor site. The nitroimidazole used to modify the polymeric skeleton can make the micellar structure collapse in response to hypoxia reduction conditions in the tumor environment, and release silibinin to widely regulate STAT3 molecules in the PDAC microenvironment. The polymer fragment attached with gemcitabine monophosphate can penetrate deep into PDAC tumors due to its small size and positive charge exposed, achieving deep chemotherapy. This research indicates a promising micelle system meeting complicated demands proposed in PDAC treatment to improve antitumor efficacy.

Antibacterial properties of photo-crosslinked chitosan/methacrylated hyaluronic acid nanoparticles loaded with bacitracin

The current treatments for wounds often fail to produce adequate healing, leaving wounds vulnerable to persistent infections and development of drug-resistant microbial biofilms. New natural-derived nanoparticles were studied to impair bacteria colonization and hinder the formation of biofilms in wounds. The nanoparticles were fabricated through polyelectrolyte complexation of chitosan (CS, polycation) and hyaluronic acid (HA, polyanion). UV-induced photo-crosslinking was used to enhance the stability of the nanoparticles. To achieve this, HA was methacrylated (HAMA, degree of modification of 20 %). Photo-crosslinked nanoparticles obtained from HAMA and CS had a diameter of 478 nm and a more homogeneous size distribution than nanoparticles assembled solely through complexation (742 nm). The nanoparticles were loaded with the antimicrobial agent bacitracin (BC), resulting in nanoparticles with a diameter of 332 nm. The encapsulation of BC was highly efficient (97 %). The BC-loaded nanoparticles showed significant antibacterial activity against gram-positive bacteria Staphylococcus aureus, Methicillin-resistant S. aureus and S. epidermidis. The nanoparticles loaded with BC based on photo-crosslinked HAMA/CS demonstrated inhibition of biofilm formation and a positive effect on the proliferation of mammalian cells (L929). These crosslinked nanoparticles have potential for the long-term treatment of wounds and controlled antibiotic delivery at the location of a lesion.

Evolving Tumor Characteristics and Smart Nanodrugs for Tumor Immunotherapy

Typical physiological characteristics of tumors, such as weak acidity, low oxygen content, and upregulation of certain enzymes in the tumor microenvironment (TME), provide survival advantages when exposed to targeted attacks by drugs and responsive nanomedicines. Consequently, cancer treatment has significantly progressed in recent years. However, the evolution and adaptation of tumor characteristics still pose many challenges for current treatment methods. Therefore, efficient and precise cancer treatments require an understanding of the heterogeneity degree of various factors in cancer cells during tumor evolution to exploit the typical TME characteristics and manage the mutation process. The highly heterogeneous tumor and infiltrating stromal cells, immune cells, and extracellular components collectively form a unique TME, which plays a crucial role in tumor malignancy, including proliferation, invasion, metastasis, and immune escape. Therefore, the development of new treatment methods that can adapt to the evolutionary characteristics of tumors has become an intense focus in current cancer treatment research. This paper explores the latest understanding of cancer evolution, focusing on how tumors use new antigens to shape their "new faces"; how immune system cells, such as cytotoxic T cells, regulatory T cells, macrophages, and natural killer cells, help tumors become "invisible", that is, immune escape; whether the diverse cancer-associated fibroblasts provide support and coordination for tumors; and whether it is possible to attack tumors in reverse. This paper discusses the limitations of targeted therapy driven by tumor evolution factors and explores future strategies and the potential of intelligent nanomedicines, including the systematic coordination of tumor evolution factors and adaptive methods, to meet this therapeutic challenge.

CD44: A New Prognostic Marker in Colorectal Cancer?

Cluster of differentiation 44 (CD44) is a non-kinase cell surface glycoprotein. It is overexpressed in several cell types, including cancer stem cells (CSCs). Cells overexpressing CD44 exhibit several CSC traits, such as self-renewal, epithelial-mesenchymal transition (EMT) capability, and resistance to chemo- and radiotherapy. The role of CD44 in maintaining stemness and the CSC function in tumor progression is accomplished by binding to its main ligand, hyaluronan (HA). The HA-CD44 complex activates several signaling pathways that lead to cell proliferation, adhesion, migration, and invasion. The CD44 gene regularly undergoes alternative splicing, resulting in the standard (CD44s) and variant (CD44v) isoforms. The different functional roles of CD44s and specific CD44v isoforms still need to be fully understood. The clinicopathological impact of CD44 and its isoforms in promoting tumorigenesis suggests that CD44 could be a molecular target for cancer therapy. Furthermore, the recent association observed between CD44 and KRAS-dependent carcinomas and the potential correlations between CD44 and tumor mutational burden (TMB) and microsatellite instability (MSI) open new research scenarios for developing new strategies in cancer treatment. This review summarises current research regarding the different CD44 isoform structures, their roles, and functions in supporting tumorigenesis and discusses its therapeutic implications.

Hyaluronic Acid Nanogels: A Promising Platform for Therapeutic and Theranostic Applications

Hyaluronic acid (HA) nanogels are a versatile class of nanomaterials with specific properties, such as biocompatibility, hygroscopicity, and biodegradability. HA nanogels exhibit excellent colloidal stability and high encapsulation capacity, making them promising tools for a wide range of biomedical applications. HA nanogels can be fabricated using various methods, including polyelectrolyte complexation, self-assembly, and chemical crosslinking. The fabrication parameters can be tailored to control the physicochemical properties of HA nanogels, such as size, shape, surface charge, and porosity, enabling the rational design of HA nanogels for specific applications. Stimulus-responsive nanogels are a type of HA nanogels that can respond to external stimuli, such as pH, temperature, enzyme, and redox potential. This property allows the controlled release of encapsulated therapeutic agents in response to specific physiological conditions. HA nanogels can be engineered to encapsulate a variety of therapeutic agents, such as conventional drugs, genes, and proteins. They can then be delivered to target tissues with high efficiency. HA nanogels are still under development, but they have the potential to become powerful tools for a wide range of theranostic or solely therapeutic applications, including anticancer therapy, gene therapy, drug delivery, and bioimaging.

Recent progress of targeted nanocarriers in diagnostic, therapeutic, and theranostic applications in colorectal cancer

Cancer at the lower end of the digestive tract, colorectal cancer (CRC), starts with asymptomatic polyps, which can be diagnosed as cancer at a later stage. It is the fourth leading cause of malignancy-associated mortality worldwide. Despite progress in conventional treatment strategies, the possibility to overcome the mortality and morbidity issues with the enhancement of the lifespan of CRC patients is limited. With the advent of nanocarrier-based drug delivery systems, a promising revolution has been made in diagnosis, treatment, and theranostic purposes for cancer management. Herein, we reviewed the progress of miniaturized nanocarriers, such as liposomes, niosomes, solid lipid nanoparticles, micelles, and polymeric nanoparticles, employed in passive and active targeting and their role in theranostic applications in CRC. With this novel scope, the diagnosis and treatment of CRC have proceeded to the forefront of innovation, where specific characteristics of the nanocarriers, such as processability, flexibility in developing precise architecture, improved circulation, site-specific delivery, and rapid response, facilitate the management of cancer patients. Furthermore, surface-engineered technologies for the nanocarriers could involve receptor-mediated deliveries towards the overexpressed receptors on the CRC microenvironment. Moreover, the potential of clinical translation of these targeted miniaturized formulations as well as the possible limitations and barriers that could impact this translation into clinical practice were highlighted. The advancement of these newest developments in clinical research and progress into the commercialization stage gives hope for a better tomorrow.

Progress in construction and release of natural polysaccharide-platinum nanomedicines: A review

Natural polysaccharides are natural biomaterials that have become candidate materials for nano-drug delivery systems due to their excellent biodegradability and biocompatibility. Platinum (Pt) drugs have been widely used in the clinical therapy for various solid tumors. However, their extensive systemic toxicity and the drug resistance acquired by cancer cells limit the applications of platinum drugs. Modern nanobiotechnology provides the possibility for targeted delivery of platinum drugs to the tumor site, thereby minimizing toxicity and optimizing the efficacies of the drugs. In recent years, numerous natural polysaccharide-platinum nanomedicine delivery carriers have been developed, such as nanomicelles, nanospheres, nanogels, etc. Herein, we provide an overview on the construction and drug release of natural polysaccharide-Pt nanomedicines in recent years. Current challenges and future prospectives in this field are also put forward. In general, combining with irradiation and tumor microenvironment provides a significant research direction for the construction of natural polysaccharide-platinum nanomedicines and the release of responsive drugs in the future.

Engineering nanoenzymes integrating Iron-based metal organic frameworks with Pt nanoparticles for enhanced Photodynamic-Ferroptosis therapy

Photodynamic therapy (PDT), as a promising strategy in cancer treatment that utilizes photosensitizers (PSs) to produce reactive oxygen species, has been widely used for eliminating cancer cells under specific wavelength light irradiation. However, the low aqueous solubility of PSs and special tumor microenvironments (TME), such as high glutathione (GSH) and tumor hypoxia remain challenges towards PDT for hypoxic tumor treatment. To address these problems, we constructed a novel nanoenzyme for enhanced PDT-ferroptosis therapy by integrating small Pt nanoparticles (Pt NPs) and near-infrared photosensitizer CyI into iron-based metal organic frameworks (MOFs). In addition, hyaluronic acid was adhered to the surface of the nanoenzymes to enhance the targeting ability. In this design, MOFs act not only as a delivery vector for PSs, but also a ferroptosis inducer. Pt NPs stabilized by MOFs were functioned as an oxygen (O₂) generator by catalyzing hydrogen peroxide into O₂ to relieve tumor hypoxia and increase singlet oxygen generation. In vitro and in vivo results demonstrated that under laser irradiation, this nanoenzyme could effectively relive the tumor hypoxia and decrease the level of GSH, resulting in enhanced PDT-ferroptosis therapy against hypoxic tumor. The proposed nanoenzymes represent an important advance in altering TME for improved clinical PDT-ferroptosis therapy, as well as their potential as effective theranostic agents for hypoxic tumors.

Delivery of siRNA using hyaluronic acid‐guided nanoparticles for downregulation of CXCR4

In this study, effective transport of small interfering RNAs (siRNAs) via hyaluronic acid (HA) receptor was carried out with biodegradable HA and low-molecular weight polyethyleneimine (PEI)-based transport systems. Gold nanoparticles (AuNPs) capable of giving photothermal response, and their conjugates with PEI and HA, were also added to the structure. Thus, a combination of gene silencing, photothermal therapy and chemotherapy, has been accomplished. The synthesized transport systems ranged in size, between 25 and 690 nm. When the particles were applied at a concentration of 100 μg mL^-1 (except AuPEI NPs) in vitro, cell viability was above 50%. Applying radiation after the conjugate/siRNA complex (especially those containing AuNP) treatment, increased the cytotoxic effect (decrease in cell viability of 37%, 54%, 13%, and 15% for AuNP, AuPEI NP, AuPEI-HA, and AuPEI-HA-DOX, respectively) on the MDA-MB-231 cell line. CXCR4 gene silencing via the synthesized complexes, especially AuPEI-HA-DOX/siRNA was more efficient in MDA-MB-231 cells (25-fold decrease in gene expression) than in CAPAN-1 cells. All these results demonstrated that the synthesized PEI-HA and AuPEI-HA-DOX conjugates can be used as siRNA carriers that are particularly effective, especially in the treatment of breast cancer.

Potential roles of hyaluronic acid in in vivo CAR T cell reprogramming for cancer immunotherapy

Chimeric antigen receptor (CAR) T cell therapy has recently shown unprecedented clinical efficacy for cancer treatment, particularly of hematological malignancies. However, the complex manufacturing processes that involve ex vivo genetic modification of autologous T cells limits its therapeutic application. CAR T cells generated in vivo provide a valid alternative immunotherapy, "off-the-shelf", for cancer treatment. This approach requires carriers for the delivery of CAR-encoding constructs, which are plasmid DNA or messenger RNA, to T cells for CAR expression to help eradicate the tumor. As such, there are a growing number of studies reporting gene delivery systems for in vivo CAR T cell therapy based on viral vectors and polymeric nanoparticles. Hyaluronic acid (HA) is a natural biopolymer that can serve for gene delivery, because of its inherent properties of cell recognition and internalization, as well as its biodegradability, biocompatibility, and presence of functional groups for the chemical conjugation of targeting ligands. In this review, the potential of HA in the delivery of CAR constructs is discussed on the basis of previous experience of HA-based nanoparticles for gene therapy. Furthermore, current studies on CAR carriers for in vivo-generated CAR T cells are included, giving an idea of a rational design of HA-based systems for the more efficient delivery of CAR to circulating T cells.

The current state of the art and future trends in RAS-targeted cancer therapies

Despite being the most frequently altered oncogenic protein in solid tumours, KRAS has historically been considered ‘undruggable’ owing to a lack of pharmacologically targetable pockets within the mutant isoforms. However, improvements in drug design have culminated in the development of inhibitors that are selective for mutant KRAS in its active or inactive state. Some of these inhibitors have proven efficacy in patients with KRAS^G12C-mutant cancers and have become practice changing. The excitement associated with these advances has been tempered by drug resistance, which limits the depth and/or duration of responses to these agents. Improvements in our understanding of RAS signalling in cancer cells and in the tumour microenvironment suggest the potential for several novel combination therapies, which are now being explored in clinical trials. Herein, we provide an overview of the RAS pathway and review the development and current status of therapeutic strategies for targeting oncogenic RAS, as well as their potential to improve outcomes in patients with RAS-mutant malignancies. We then discuss challenges presented by resistance mechanisms and strategies by which they could potentially be overcome.

The RAS oncogenes are among the most common drivers of tumour development and progression but have historically been considered undruggable. The development of direct KRAS inhibitors has changed this paradigm, although currently clinical use of these novel therapeutics is limited to a select subset of patients, and intrinsic or acquired resistance presents an inevitable challenge to cure. Herein, the authors provide an overview of the RAS pathway in cancer and review the ongoing efforts to develop effective therapeutic strategies for RAS-mutant cancers. They also discuss the current understanding of mechanisms of resistance to direct KRAS inhibitors and strategies by which they might be overcome.

Owing to intrinsic and extrinsic factors, KRAS and other RAS isoforms have until recently been impervious to targeting with small-molecule inhibitors.

Inhibitors of the KRAS^G12C variant constitute a potential breakthrough in the treatment of many cancer types, particularly non-small-cell lung cancer, for which such an agent has been approved by the FDA.

Several forms of resistance to KRAS inhibitors have been defined, including primary, adaptive and acquired resistance; these resistance mechanisms are being targeted in studies that combine KRAS inhibitors with inhibitors of horizontal or vertical signalling pathways.

Mutant KRAS has important effects on the tumour microenvironment, including the immunological milieu; these effects must be considered to fully understand resistance to KRAS inhibitors and when designing novel treatment strategies.

Droplet-based microfluidic synthesis of nanogels for controlled drug delivery: tailoring nanomaterial properties via pneumatically actuated flow-focusing junction

Conventional batch syntheses of polymer-based nanoparticles show considerable shortcomings in terms of scarce control over nanomaterials morphology and limited lot-to-lot reproducibility. Droplet-based microfluidics represents a valuable strategy to overcome these constraints, exploiting the formation of nanoparticles within discrete microdroplets. In this work, we synthesized nanogels (NGs) composed of hyaluronic acid and polyethyleneimine using a microfluidic flow-focusing device endowed with a pressure-driven micro-actuator. The actuator achieves real-time modulation of the junction orifice width, thereby regulating the microdroplet diameter and, as a result, the NG size. Acting on process parameters, NG hydrodynamic diameter could be tuned in the range 92-190 nm while preserving an extremely low polydispersity (0.015); those values are hardly achievable in batch syntheses and underline the strength of our toolbox for the continuous in-flow synthesis of nanocarriers. Furthermore, NGs were validated in vitro as a drug delivery system in a representative case study still lacking an effective therapeutic treatment: ovarian cancer. Using doxorubicin as a chemotherapeutic agent, we show that NG-mediated release of the drug results in an enhanced antiblastic effect vs. the non-encapsulated administration route even at sublethal dosages, highlighting the wide applicability of our microfluidics-enabled nanomaterials in healthcare scenarios.

Targeted delivery and enhanced uptake of chemo-photodynamic nanomedicine for melanoma treatment

Nanoparticles (NPs) modified with targeting ligands have often shown great potential in targeted drug delivery for tumor therapy. However, the clearance of NPs by the monocyte-phagocyte system (MPS) and the relatively low cellular uptake by tumor cells have significantly limited the antitumor efficacy of a variety of nanomedicines. Tumor microenvironment-mediated multidrug resistance also reduces the antitumor efficacy of internalized nanomedicines. Herein, we developed an innovative nanomedicine for combined chemo-photodynamic therapy of melanoma through targeted drug delivery and significantly improved the cellular uptake of the nanomedicine through the charge-reversal phenomenon. An amphiphilic platinum (IV)-polyethylenimine-chlorin e6 (Pt(IV)-PEI-Ce6) polymer was designed, prepared, and self-assembled into NPs (PPC) in an aqueous solution, and these NPs were subsequently coated with hyaluronic acid (HA) to afford PPC@HA. The surface-coated HA provided PPC with a negatively charged surface potential to reduce the clearance by the MPS during systemic circulation and enhanced the targeted delivery of PPC to CD44-overexpressing melanoma cells. Upon accumulation in the tumor site, hyaluronidase overexpressed in the tumor induced HA degradation to release the positively charged PPC, resulting in an increased internalization of PPC into tumor cells. Bioactive Pt(II) was released in response to high glutathione level in the tumor cells for effective tumor chemotherapy. Under 650 nm laser irradiation, Ce6 produced reactive oxygen species (ROS), thus driving photodynamic therapy. Finally, PPC@HA exhibited combined photodynamic-chemotherapeutic antitumor efficacy against the melanoma cells in mice. STATEMENT OF SIGNIFICANCE: Tumors are one of the greatest threats to human health, and chemotherapy has been one of the most common therapeutic modalities for treating tumors; however, many challenges related to chemotherapy remain, such as low delivery efficiency, side effects, and unsatisfactory therapeutic efficacy. Nanomedicines modified with targeting ligands have often shown great potential in improving targeted drug delivery for tumor therapy; however, the clearance of nanomaterials by the monocyte-phagocyte system and the relatively low cellular uptake by tumor cells have significantly limited the antitumor efficacy of a variety of nanomedicines. Herein, we developed a novel charge-reversal-based, hyaluronic acid-coated, Pt(IV) prodrug and chlorin e6-based nanomedicine to improve systemic circulation and targeted accumulation of the nanomedicine in the tumor tissue and to enhance its intracellular uptake. This nanomedicine may provide a potential new platform to improve the drug content inside tumor cells and to effectively inhibit tumor growth through combined chemotherapy and photodynamic therapy.

CD44-Targeted Nanocarrier for Cancer Therapy

Cluster of differentiation 44 (CD44) is a cell surface glycoprotein overexpressed in varieties of solid tumors including pancreatic, breast, ovary, brain, and lung cancers. It is a multi-structural glycoprotein of the cell surface which is majorly involved in cell proliferation, cell-to-cell interaction, cellular migration, inflammation, and generation of immune responses. Numerous studies focus on the development of nanocarriers for active targeting of the CD44 receptor to improve efficacy of targeting chemotherapy and achieve precise chemotherapy by defining the release, uptake, and accumulation of therapeutic agents. The CD44 receptor has a selective binding affinity towards hyaluronic and chondroitin sulfate (CS). Taking this into consideration, this review focused on the role of CD44 in cancer and its therapy using several nanocarriers such as polymeric/non-polymeric nanoparticles, dendrimer, micelles, carbon nanotubes, nanogels, nanoemulsions etc., for targeted delivery of several chemotherapeutic molecules and nucleic acid. This review also illuminates the role of hyaluronic acid (HA) in cancer therapy, interaction of HA with CD44, and various approaches to target CD44-overexpressed neoplastic cells.

CD44: A Multifunctional Mediator of Cancer Progression

CD44, a non-kinase cell surface transmembrane glycoprotein, has been widely implicated as a cancer stem cell (CSC) marker in several cancers. Cells overexpressing CD44 possess several CSC traits, such as self-renewal and epithelial-mesenchymal transition (EMT) capability, as well as a resistance to chemo- and radiotherapy. The CD44 gene regularly undergoes alternative splicing, resulting in the standard (CD44s) and variant (CD44v) isoforms. The interaction of such isoforms with ligands, particularly hyaluronic acid (HA), osteopontin (OPN) and matrix metalloproteinases (MMPs), drive numerous cancer-associated signalling. However, there are contradictory results regarding whether high or low CD44 expression is associated with worsening clinicopathological features, such as a higher tumour histological grade, advanced tumour stage and poorer survival rates. Nonetheless, high CD44 expression significantly contributes to enhanced tumourigenic mechanisms, such as cell proliferation, metastasis, invasion, migration and stemness; hence, CD44 is an important clinical target. This review summarises current research regarding the different CD44 isoform structures and their roles and functions in supporting tumourigenesis and discusses CD44 expression regulation, CD44-signalling pathways and interactions involved in cancer development. The clinical significance and prognostic value of CD44 and the potential of CD44 as a therapeutic target in cancer are also addressed.

Dasatinib self-assembled nanoparticles decorated with hyaluronic acid for targeted treatment of tumors to overcome multidrug resistance

Multidrug resistance (MDR) and lack of targeting specificity are the main reasons why traditional drug therapies fail and produce toxic side effects in cancer chemotherapy. In order to increase targeting specificity and maximize therapeutic efficacy, new intelligent drug delivery systems are needed. In this study, we prepared the hyaluronic acid (HA) conjugated dasatinib (DAS) and D-α-tocopherol acid polyethylene glycolsuccinate (TPGS) copolymer nanoparticles (THD-NPs). The water solubility of the hydrophobic drug DAS was improved by chemically linking with HA. HA can bind to the over-expressed CD44 protein of tumor cells to increase targeting specificity, TPGS can inhibit the activity of P-glycoprotein (P-gp), and increase the intracellular accumulation of drugs. The prepared drug-loaded nanoparticle has a particle size of 82.23 ± 1.07 nm with good in vitro stability. Our in vitro studies showed that THD-NPs can be released more rapidly in a weakly acidic environment (pH = 5.5) than in a normal physiological environment (pH = 7.4), which can realize the selective release of nanoparticles in tumor cells. Compared to free drugs, THD-NPs showed more efficient cellular uptake, effectively increased the cytotoxic effect of DAS on nasopharyngeal carcinoma HNE1 cells drug resistance HNE1/DDP cells and increased the accumulation of drugs in HNE1/DDP cells, which may be due to the inhibitory effect of TPGS on the efflux function of P-gp. In vivo experiments showed that THD-NPs can effectively inhibit tumor growth without obvious side effects. In conclusion, the targeted and pH-sensitive nanosystem, we designed has great potential to overcome drug resistance and increase therapeutic effects in cancer treatment.

Preparation of docetaxel-loaded, glycyrrhetinic acid-modified nanoparticles and their liver-targeting and antitumor activity

Liver cancer is one of the most common malignancies worldwide and poses a serious threat to human health. The most important treatment method, liver cancer chemotherapy, is limited due to its high toxicity and poor specificity. Targeted drug delivery systems have emerged as novel therapeutic strategies that deliver precise, substantial drug doses to target sites via targeting vectors and enhance the therapeutic efficacy. In the present study, glycyrrhetinic acid-modified hyaluronic acid (GA-HA) was used as a carrier for the model drug docetaxel (DTX) to prepare DTX-loaded GA-HA nanoparticles (DTX/GA-HA-NPs). The results indicated that the DTX/GA-HA-NPs exhibited high monodispersity (particle dispersity index, 0.209±0.116) and desirable particle size (208.73±5.0 nm) and zeta potential (-27.83±3.14 mV). The drug loading capacity and encapsulation efficiency of the NPs were 12.59±0.68 and 85.38±4.62%, respectively. Furthermore, it was determined that FITC-GA-HA was taken up by cells and distributed in the cytoplasm. DTX and DTX/GA-HA (just the DTX delivered by the nanoparticle) aggregated and altered the structure of cellular microtubules. Compared with DTX alone, DTX/GA-HA-NPs had a stronger inhibitory effect on HepG2 cell proliferation and promoted apoptosis of HepG2 cells. All experimental results indicated that DTX/GA-HA-NPs were successfully prepared and had liver-targeting and antitumor activities in vitro, which provided a foundation for future in vivo studies of the antitumor effects of DTX/GA-HA-NPs.

Combination Therapy with KRAS and P38α siRNA Suppresses Colorectal Cancer Growth and Development in SW480 Cell Line

PURPOSE

Colorectal cancer (CRC) is one of the most prevalence malignancies in a different society with a high rate of death. The KRAS and p38α axes have critical roles in the development, migration, and growth of numerous tumors, such as colorectal malignancy. KRAS mutation acts as an oncogene in various cancers and is correlated with the poor prognosis in colorectal tumors. Also, p38α plays different roles and exhibits tissue-dependent activity. In some tissues act as an oncogene while in others act as a tumor suppressor. In this research, we try to understand the effect of the P38α and KRAS genes suppression by specific siRNAs on the SW480 cell line progression.

METHODS

We evaluate the impact of the P38α and KRAS gene knockdown by special siRNA on the growth and development of the SW480 cell line. SW480 cell line was treated with KRAS and P38α siRNAs, and the cell viability, gene expression, migration ability, and rate of apoptosis were evaluated with MTT assay, real-time PCR, scratch test, and flow cytometry.

RESULTS

After treatment of the cancer cell with KRAs and P38α siRNAs, cell viability reduced to 29.16%. Also, the expression levels of the KRAS and P38α genes reduced to 26.34% and 16.06%, respectively. Apoptosis rate after combination therapy with KRAS and P38α siRNAs increased to 72.1. Also, we found that these siRNAs suppress cell migration in SW480 cell lines.

CONCLUSION

The current study showed that combination therapy with p38α and KRAS siRNA may be considered a novel therapy for colorectal tumor in future.

Multimodality labeling of NGR-functionalized hyaluronan for tumor targeting and radiotherapy

Hyaluronan (HA) is a negatively charged linear polysaccharide that can interact with cluster determinant 44 (CD44) overexpressed cancers. However, HA can also bind to excess substrates in the human body leading to the lower specificity of tumor targeting. Conjugation of other targeting group to HA could enhance the uptake by cancer cell comparing to that of native HA. In this study, we develop the multi-functionalized HA (¹⁷⁷Lu-DOTA/Alexa647-HA100-N) for malignant tumor targeting. An asparagine-glycine-arginine (NGR) based peptide was selected for HA functionalization. The peptide is known to target CD13 receptor that is overexpressed in malignant tumors with abundant blood vessels, such as lung cancer. Furthermore, the fluorescent probe Alexa Fluor 647 for ex vivo/in vivo tracking and the radionuclide ¹⁷⁷Lu for radioactive therapy were both labeled on the material. The functionalized HA could be bound by lung cancer cells and breast cancer cells. In vivo fluorescent imaging showed that the material could accumulate in the tumor site for more than 96 h. The ¹⁷⁷Lu labeling of functionalized HA was stable for more 48 h at physiological conditions. The accumulation of ¹⁷⁷Lu-DOTA/Alexa647-HA100-N in the tumor of lung cancer (NCI-H292) bearing mice was 1.91±0.97%ID/g, and it was about 17 times higher than the value in blood. Conclusion: The multimodality labeled functional HA was successfully prepared and could be fluorescent trackable ex vivo and in vivo. It showed high potential to be used for malignant cancer radiotherapy for its specific targeting property to tumors and radiotoxicity from the labeled ¹⁷⁷Lu radionuclide.

Ligand decorated biodegradable nanomedicine in the treatment of cancer

Cancer is one of the major global health problems, responsible for the second-highest number of deaths. The genetic and epigenetic changes in the oncogenes or tumor suppressor genes alter the regulatory pathways leading to its onset and progression. Conventional methods are used in appropriate combinations for the treatment. Surgery effectively treats localized tumors; however, it fails to treat metastatic tumors, leading to a spread in other organs, causing a high recurrence rate and death. Among the different strategies, the nanocarriers-based approach is highly sought for, but its nonspecific delivery can cause a profound side effect on healthy cells. Targeted nanomedicine has the advantage of targeting cancer cells specifically by interacting with the receptors overexpressed on their surface, overcoming its non-specificity to target healthy cells. Nanocarriers prepared from biodegradable and biocompatible materials are decorated with different ligands by encapsulating therapeutic or diagnostic agents or both to target cancer cells overexpressing the receptors. Scientists are now utilizing a theranostic approach to simultaneously evaluate nanocarrier bio-distribution and its effect on the treatment regime. Herein, we have summarized the recent 5-year efforts in the development of the ligands decorated biodegradable nanocarriers, as a targeted nanomedicine approach, which has been highly promising in the treatment of cancer.

Engineered nanoparticles for imaging and drug delivery in colorectal cancer

Colorectal cancer (CRC) is one of the deadliest diseases worldwide due to a lack of early detection methods and appropriate drug delivery strategies. Conventional imaging techniques cannot accurately distinguish benign from malignant tissue, leading to frequent misdiagnosis or diagnosis at late stages of the disease. Novel screening tools with improved accuracy and diagnostic precision are thus required to reduce the mortality burden of this malignancy. Additionally, current therapeutic strategies, including radio- and chemotherapies carry adverse side effects and are limited by the development of drug resistance. Recent advances in nanotechnology have rendered it an attractive approach for designing novel clinical solutions for CRC. Nanoparticle-based formulations could assist early tumor detection and help to overcome the limitations of conventional therapies including poor aqueous solubility, nonspecific biodistribution and limited bioavailability. In this review, we shed light on various types of nanoparticles used for diagnosis and drug delivery in CRC. In addition, we will explore how these nanoparticles can improve diagnostic accuracy and promote selective drug targeting to tumor sites with increased efficiency and reduced cytotoxicity against healthy colon tissue.

Codelivery of STAT3 and PD-L1 siRNA by hyaluronate-TAT trimethyl/thiolated chitosan nanoparticles suppresses cancer progression in tumor-bearing mice

Immunotherapy methods using potential tumor microenvironment modulators have elicited durable therapeutic responses in cancer treatment. Immune checkpoint molecule programmed cell death-ligand 1 (PD-L1) and oncogenic transcription factor STAT3 (signal transducer and activator of transcription-3) assigned as inhibitory targets of our study and particular delivery system designed to deliver small interfering RNAs (siRNAs) to silence the targeted genes. Generated trimethyl chitosan (TMC) and thiolated chitosan (TC) nanoparticles (NPs) conjugated with HIV-1-derived TAT peptide and HA (hyaluronic acid) exhibited eligible physicochemical characteristics, notable siRNA encapsulation, serum stability, non-toxicity, controlled siRNA release, and extensive cellular uptake by cancer cells. Dual inhibition with STAT3/PD-L1 siRNA-loaded HA-TAT-TMC-TC NPs led to promising results, including significant downregulation of PD-L1 and STAT3 genes, striking suppressive effects on proliferation, migration, and angiogenesis of breast and melanoma cancer cell lines, and restrained tumor growth in vivo. These findings infer the capability of HA-TAT-TMC-TC NPs containing STAT3/PD-L1 siRNAs as a novel tumor-suppressive candidate in cancer treatment.

Cellular gene delivery via poly(hexamethylene biguanide)/pDNA self-assembled nanoparticles

Cellular gene delivery via polycations has wide implications for the potential of gene therapy, but it has remained a challenge due to the plethora of pre- and post-uptake barriers that must be overcome to reach desired efficiency. Herein we report poly(hexamethylene biguanide) (PHMB) as a nano-vector for intracellular delivery of plasmid DNA (pDNA) and oligodeoxynucleotides (ODNs). PHMB and pDNA or ODNs self-assembled into complex nanoparticles at different pH values (7.4 and 12). Their size, charge, cellular uptake, and gene-expression efficiency are assessed and compared to PEI analogues. The systematic results show that the nanoparticles are effective in delivering plasmid DNA and ODNs to model cell lines in culture (HepG2, HEK293T, HeLa), with measurable changes in gene expression levels, comparable to and, in some conditions, even higher than PEI. The well-accepted safety profile of PHMB makes it a valuable candidate for consideration as an effective intracellular DNA vector for further study and potential clinical translation.

Surface-functionalised hybrid nanoparticles for targeted treatment of cancer

Cancer is a leading cause of death worldwide. Despite the great advancement in understanding the pharmacology and biology of cancer, it still signifies one of the most serious human-health related problems. The current treatments for cancer may include surgery, radiotherapy, and chemotherapy, but these procedures have several limitations. Current studies have shown that nanoparticles (NPs) can be used as a novel strategy for cancer treatment. Developing nanosystems that allow lower doses of therapeutic agents, as well as their selective release in tumour cells, may resolve the challenges of targeted cancer therapy. In this review, the authors discuss the role of the size, shape, and surface modifications of NPs in cancer treatment. They also address the challenges associated with cancer therapies based on NPs. The overall purpose of this review is to summarise the recent developments in designing different hybrid NPs with promising therapeutic properties for different types of cancer.

Oxygen-producing catalase-based prodrug nanoparticles overcoming resistance in hypoxia-mediated chemo-photodynamic therapy

Extreme hypoxia inside solid tumors is the primary barrier against the advance of chemotherapy and photodynamic therapy (PDT). To address this problem, a hybrid nano-enzyme prodrug system was developed to alleviate hypoxia as well as simultaneously sensitize chemo-photodynamic therapy. Lactobionic acid (LA) and doxorubicin (DOX) precursor (cis-aconitic anhydride-linked doxorubicin, CAD) were pre-conjugated onto the side chain of catalase (CAT), then co-assembled with chlorin e6 (Ce6) to form LA-CAT-CAD@Ce6 nanoparticles (LCC@Ce6-NPs). LA as the active-targeting ligand increased cellular internalization, CAD as the pH-sensitive component triggered rapid drug release, Ce6 as the photosensitizer induced reactive oxygen species (ROS) generation, and CAT decomposed intracellular H₂O₂ to produce oxygen in situ. Oxygen production efficiently decreased the expression of hypoxia-inducible factor-1α (HIF-1α) and P-glycoprotein (P-gp), which enhanced chemotherapy efficiency. In addition, sufficient oxygen further amplified PDT-mediated cell-killing and apoptosis in hypoxic tumor. In vivo studies showed that combined chemo-photodynamic therapy by LCC@Ce6-NPs led to the most effective inhibition of tumor growth (TGI>90%), and even partially ablated tumor. Thus, this nano-enzyme prodrug platform can be a potentially effective treatment in clinical cancer therapy, and married to other therapeutic agents. STATEMENT OF SIGNIFICANCE: Hypoxia in solid tumors seriously impedes the efficacy of chemotherapy or photodynamic therapy. Herein, we designed hybrid nano-enzyme prodrug particles to improve hypoxia-mediated limitations on cancer therapy. Lactobionic acid (LA) as the hydrophilic outer layer of particles increased cellular uptake by receptor-mediated endocytosis, and cis-aconitic anhydride-linked doxorubicin (CAD) as the pH sensitive component inside particles efficiently triggered DOX and Ce6 release. More importantly, catalase (CAT) as the backbone of particles was capable of greatly relieving tumor hypoxia through catalyzing the decomposition of H2O2 in situ. Oxygen re-generation not only prevented hypoxia-mediated chemo-resistance, but also amplified PDT-induced ROS cell-killing ability. As a result, the multiple combination action of this nano-system could simultaneously sensitize chemo-photodynamic therapy, thus significantly enhancing tumor therapy.

Silencing of IL-6 and STAT3 by siRNA loaded hyaluronate-N,N,N-trimethyl chitosan nanoparticles potently reduces cancer cell progression

The immunosuppressive nature of the tumor microenvironment is a critical problem that should be considered before the design of immunotherapies. Interleukin (IL)-6 and its related downstream molecules such as signal transducer and activator of transcription (STAT)3 play an important role in the cancer progression, which can be considered as potential therapeutic targets. In the present study, we generated the active-targeted hyaluronate (HA) recoated N, N, N-trimethyl chitosan (TMC) nanoparticles (NPs) to deliver IL-6- and STAT3-specific small interfering RNAs (siRNAs) to the CD44-expressing cancer cells. We utilized the interaction between HA and CD44 to increase the specificity and efficacy of cellular uptake in NPs. The results showed that the synthesized NPs had efficient physicochemical characteristics, high transfection efficiency, low toxicity, and controlled siRNA release. siRNA-loaded NPs significantly inhibited the IL-6/STAT3 expression, which was associated with blockade of proliferation, colony formation, migration, and angiogenesis in cancer cells. These findings imply the potential of HA-TMC NPs as potent vectors in gene therapy and their application for the silencing of IL-6 and STAT3, as a novel anti-cancer combination therapeutic strategy, for the first time.

Binding and Internalization in Receptor-Targeted Carriers: The Complex Role of CD44 in the Uptake of Hyaluronic Acid-Based Nanoparticles (siRNA Delivery)

CD44 is an endocytic hyaluronic acid (HA) receptor, and is overexpressed in many carcinomas. This has encouraged the use of HA to design CD44-targeting carriers. This paper is about dissecting the mechanistic role of CD44. Here, HA-decorated nanoparticles are used to deliver siRNA to both tumoral (AsPC-1, PANC-1, HT-29, HCT-116) and non-tumoral (fibroblasts, differently polarized THP-1 macrophages, HUVEC) human cell lines, evaluating the initial binding of the nanoparticles, their internalization rate, and the silencing efficiency (cyclophilin B (PPIB) gene). Tumoral cells internalize faster and experience higher silencing than non-tumoral cells. This is promising as it suggests that, in a tumor, HA nanocarriers may have limited off-target effects. More far-reaching is the inter-relation between the four parameters of the study: CD44 expression, HA binding on cell surfaces, internalization rate, and silencing efficiency. No correlation is found between binding (an early event) and any of the other parameters, whereas silencing correlates both with speed of the internalization process and CD44 expression. This study confirms on one hand that HA-based carriers can perform a targeted action, but on the other it suggests that this may not be due to a selective binding event, but rather to a later recognition leading to selective internalization.

Extracellular matrix-cell interactions: Focus on therapeutic applications

Extracellular matrix (ECM) macromolecules together with a multitude of different molecules residing in the extracellular space play a vital role in the regulation of cellular phenotype and behavior. This is achieved via constant reciprocal interactions between the molecules of the ECM and the cells. The ECM-cell interactions are mediated via cell surface receptors either directly or indirectly with co-operative molecules. The ECM is also under perpetual remodeling process influencing cell-signaling pathways on its part. The fragmentation of ECM macromolecules provides even further complexity for the intricate environment of the cells. However, as long as the interactions between the ECM and the cells are in balance, the health of the body is retained. Alternatively, any dysregulation in these interactions can lead to pathological processes and finally to various diseases. Thus, therapeutic applications that are based on retaining normal ECM-cell interactions are highly rationale. Moreover, in the light of the current knowledge, also concurrent multi-targeting of the complex ECM-cell interactions is required for potent pharmacotherapies to be developed in the future.

SWAP-70 promotes glioblastoma cellular migration and invasion by regulating the expression of CD44s

BACKGROUND

Switch-associated protein 70 (SWAP-70) is a guanine nucleotide exchange factor that is involved in cytoskeletal rearrangement and regulation of migration and invasion of malignant tumors. However, the mechanism by which SWAP-70 regulates the migration and invasion of glioblastoma (GB) cells has not been fully elucidated.

METHODS

This study used an online database to analyze the relationship between SWAP-70 expression and prognosis in GB patients. The in vitro wound healing assay and transwell invasion assay were used to determine the role of SWAP-70 in GB cell migration and invasion as well as the underlying mechanism.

RESULTS

We found that patients with high SWAP-70 expression in the GB had a poor prognosis. Downregulation of SWAP-70 inhibited GB cell migration and invasion, whereas SWAP-70 overexpression had an opposite effect. Interestingly, SWAP-70 expression was positively correlated with the expression of the standard form of CD44 (CD44s) in GB tissues. Downregulation of SWAP-70 also reduced CD44s protein expression, whereas SWAP-70 overexpression enhanced CD44s protein expression. However, downregulation of SWAP-70 expression did not affect the mRNA expression of CD44s. Reversal experiments showed that overexpressing CD44s in cell lines with downregulated SWAP-70 partially abolished the inhibitory effects of downregulated SWAP-70 on GB cell migration and invasion.

CONCLUSIONS

These results suggest that SWAP-70 may promote GB cell migration and invasion by regulating the expression of CD44s. SWAP-70 may serve as a new biomarker and a potential therapeutic target for GB.

Biodegradable Polymers for Gene Delivery

The cellular transport process of DNA is hampered by cell membrane barriers, and hence, a delivery vehicle is essential for realizing the potential benefits of gene therapy to combat a variety of genetic diseases. Virus-based vehicles are effective, although immunogenicity, toxicity and cancer formation are among the major limitations of this approach. Cationic polymers, such as polyethyleneimine are capable of condensing DNA to nanoparticles and facilitate gene delivery. Lack of biodegradation of polymeric gene delivery vehicles poses significant toxicity because of the accumulation of polymers in the tissue. Many attempts have been made to develop biodegradable polymers for gene delivery by modifying existing polymers and/or using natural biodegradable polymers. This review summarizes mechanistic aspects of gene delivery and the development of biodegradable polymers for gene delivery.

Natural Polysaccharides for siRNA Delivery: Nanocarriers Based on Chitosan, Hyaluronic Acid, and Their Derivatives

Natural polysaccharides are frequently used in the design of drug delivery systems due to their biocompatibility, biodegradability, and low toxicity. Moreover, they are diverse in structure, size, and charge, and their chemical functional groups can be easily modified to match the needs of the final application and mode of administration. This review focuses on polysaccharidic nanocarriers based on chitosan and hyaluronic acid for small interfering RNA (siRNA) delivery, which are highly positively and negatively charged, respectively. The key properties, strengths, and drawbacks of each polysaccharide are discussed. In addition, their use as efficient nanodelivery systems for gene silencing applications is put into context using the most recent examples from the literature. The latest advances in this field illustrate effectively how chitosan and hyaluronic acid can be modified or associated with other molecules in order to overcome their limitations to produce optimized siRNA delivery systems with promising in vitro and in vivo results.

The different ways to chitosan/hyaluronic acid nanoparticles: templated vs direct complexation. Influence of particle preparation on morphology, cell uptake and silencing efficiency

This study is about linking preparative processes of nanoparticles with the morphology of the nanoparticles and with their efficiency in delivering payloads intracellularly. The nanoparticles are composed of hyaluronic acid (HA) and chitosan; the former can address a nanoparticle to cell surface receptors such as CD44, the second allows both for entrapment of nucleic acids and for an endosomolytic activity that facilitates their liberation in the cytoplasm. Here, we have systematically compared nanoparticles prepared either A) through a two-step process based on intermediate (template) particles produced via ionotropic gelation of chitosan with triphosphate (TPP), which are then incubated with HA, or B) through direct polyelectrolyte complexation of chitosan and HA. Here we demonstrate that HA is capable to quantitatively replace TPP in the template process and significant aggregation takes place during the TPP-HA exchange. The templated chitosan/HA nanoparticles therefore have a mildly larger size (measured by dynamic light scattering alone or by field flow fractionation coupled to static or dynamic light scattering), and above all a higher aspect ratio (R _g/R _H) and a lower fractal dimension. We then compared the kinetics of uptake and the (antiluciferase) siRNA delivery performance in murine RAW 264.7 macrophages and in human HCT-116 colorectal tumor cells. The preparative method (and therefore the internal particle morphology) had little effect on the uptake kinetics and no statistically relevant influence on silencing (templated particles often showing a lower silencing). Cell-specific factors, on the contrary, overwhelmingly determined the efficacy of the carriers, with, e.g., those containing low-MW chitosan performing better in macrophages and those with high-MW chitosan in HCT-116.