CD44-overexpressing Cells Research Articles

Zein-PEG nanoparticles modified with hyaluronic acid for paclitaxel delivery in SKOV3 ovarian cancer cells

Ovarian cancer is a leading gynecological cancer globally. This study aimed to develop hyaluronic acid-modified polyethylene glycol conjugated zein nanoparticles (zein-PEG/HA NPs) to enhance paclitaxel (PTX) cytotoxicity in SKOV3 ovarian cancer cells. Zein-PEG, with its amphiphilic nature, self-assembled into micelles to encapsulate the hydrophobic PTX, while the PEG shell retained micelle stability and hemolytic resistance. PTX@zein-PEG micelles (17.2 ± 0.3 mV) were complexed with negatively charged HA through electrostatic interactions, resulting in PTX@zein-PEG/HA NPs with a negative zeta potential of −15.3 ± 1.1 mV. Cellular uptake of fluorescent zein-PEG/HA NPs was higher than zein-PEG micelles in CD44-overexpressing SKOV3 cells. Additionally, PTX@zein-PEG/HA NPs demonstrated significantly greater cytotoxicity than free PTX and PTX@zein-PEG micelles, with IC50 values reduced by 6.13-fold and 3.58-fold, respectively. PTX@zein-PEG/HA NPs induced the highest expression levels of apoptotic proteins, particularly PARP, in SKOV3 cells compared to PTX@zein-PEG NPs and free PTX. In summary, PTX@zein-PEG/HA NPs demonstrated potential as a delivery system for PTX in ovarian cancer.

Targeting pentamidine towards CD44-overexpressing cells using hyaluronated lipid-polymer hybrid nanoparticles.

Biodegradable nanocarriers possess enormous potential for use as drug delivery systems that can accomplish controlled and targeted drug release, and a wide range of nanosystems have been reported for the treatment and/or diagnosis of various diseases and disorders. Of the various nanocarriers currently available, liposomes and polymer nanoparticles have been extensively studied and some formulations have already reached the market. However, a combination of properties to create a single hybrid system can give these carriers significant advantages, such as improvement in encapsulation efficacy, higher stability, and active targeting towards specific cells or tissues, over lipid or polymer-based platforms. To this aim, this work presents the formulation of poly(lactic-co-glycolic) acid (PLGA) nanoparticles in the presence of a hyaluronic acid (HA)-phospholipid conjugate (HA-DPPE), which was used to anchor HA onto the nanoparticle surface and therefore create an actively targeted hybrid nanosystem. Furthermore, ionic interactions have been proposed for drug encapsulation, leading us to select the free base form of pentamidine (PTM-B) as the model drug. We herein report the preparation of hybrid nanocarriers that were loaded via ion-pairing between the negatively charged PLGA and HA and the positively charged PTM-B, demonstrating an improved loading capacity compared to PLGA-based nanoparticles. The nanocarriers displayed a size of below 150nm, a negative zeta potential of -35mV, a core-shell internal arrangement and high encapsulation efficiency (90%). Finally, the ability to be taken up and exert preferential and receptor-mediated cytotoxicity on cancer cells that overexpress the HA specific receptor (CD44) has been evaluated. Competition assays supported the hypothesis that PLGA/HA-DPPE nanoparticles deliver their cargo within cells in a CD44-dependent manner.

Antioxidative Hyaluronic Acid-Bilirubin Nanomedicine Targeting Activated Hepatic Stellate Cells for Anti-Hepatic-Fibrosis Therapy.

Liver fibrosis is a life-threatening and irreversible disease. The fibrosis process is largely driven by hepatic stellate cells (HSCs), which undergo transdifferentiation from an inactivated state to an activated one during persistent liver damage. This activated state is responsible for collagen deposition in liver tissue and is accompanied by increased CD44 expression on the surfaces of HSCs and amplified intracellular oxidative stress, which contributes to the fibrosis process. To address this problem, we have developed a strategy that combines CD44-targeting of activated HSCs with an antioxidative approach. We developed hyaluronic acid-bilirubin nanoparticles (HABNs), composed of endogenous bilirubin, an antioxidant and anti-inflammatory bile acid, and hyaluronic acid, an endogenous CD44-targeting glycosaminoglycan biopolymer. Our findings demonstrate that intravenously administered HABNs effectively targeted the liver, particularly activated HSCs, in fibrotic mice with choline-deficient l-amino acid-defined high-fat diet (CD-HFD)-induced nonalcoholic steatohepatitis (NASH). HABNs were able to inhibit HSC activation and proliferation and collagen production. Furthermore, in a murine CD-HFD-induced NASH fibrosis model, intravenously administered HABNs showed potent fibrotic modulation activity. Our study suggests that HABNs have the potential to serve as a targeted anti-hepatic-fibrosis therapy by modulating activated HSCs via CD44-targeting and antioxidant strategies. This strategy could also be applied to various ROS-related diseases in which CD44-overexpressing cells play a pivotal role.

Hyaluronic Acid-Bilirubin Nanoparticles as a Tumor Microenvironment Reactive Oxygen Species-Responsive Nanomedicine for Targeted Cancer Therapy.

The tumor microenvironment (TME) has attracted considerable attention as a potential therapeutic target for cancer. High levels of reactive oxygen species (ROS) in the TME may act as a stimulus for drug release. In this study, we have developed ROS-responsive hyaluronic acid-bilirubin nanoparticles (HABN) loaded with doxorubicin (DOX@HABN) for the specific delivery and release of DOX in tumor tissue. The hyaluronic acid shell of the nanoparticles acts as an active targeting ligand that can specifically bind to CD44-overexpressing tumors. The bilirubin core has intrinsic anti-cancer activity and ROS-responsive solubility change properties. DOX@HABN showed the HA shell-mediated targeting ability, ROS-responsive disruption leading to ROS-mediated drug release, and synergistic anti-cancer activity against ROS-overproducing CD44-overexpressing HeLa cells. Additionally, intravenously administered HABN-Cy5.5 showed remarkable tumor-targeting ability in HeLa tumor-bearing mice with limited distribution in major organs. Finally, intravenous injection of DOX@HABN into HeLa tumor-bearing mice showed synergistic anti-tumor efficacy without noticeable side effects. These findings suggest that DOX@HABN has significant potential as a cancer-targeting and TME ROS-responsive nanomedicine for targeted cancer treatment.

DON encapsulated carbon dot-vesicle conjugate in therapeutic intervention of lung adenocarcinoma by dual targeting of CD44 and SLC1A5.

Lung adenocarcinoma, recognized as one of the most formidable malignancies with a dismal prognosis and low survival rates, poses a significant challenge in its treatment. This article delineates the design and development of a carbon dot-vesicle conjugate (HACD-TMAV) for efficient cytotoxicity towards lung cancer cells by target selective delivery of the glutamine inhibitor 6-diazo-5-oxo-L-norleucine (DON) within CD44-enriched A549 cancer cells. HACD-TMAV is composed of hyaluronic acid-based carbon dots (HACDs) and trimesic acid-based vesicles (TMAV), which are bound via electrostatic interactions. TMAVs are formed by positively charged trimesic acid-based amphiphiles through H-type aggregation in water. HACDs were synthesized through a one-step hydrothermal route. The blue-emitting HACD-TMAV conjugate demonstrated selective bioimaging in CD44-overexpressed A549 lung cancer cells due to specific ligand-receptor interactions between HA and CD44. HACD-TMAV exhibited notably improved DON loading efficiency compared to individual nano-vehicles. HACD-TMAV-DON exhibited remarkable (∼6.0-fold higher) cytotoxicity against CD44-overexpressing A549 cells compared to CD44- HepG2 cells and HEK 293 normal cells. Also, DON-loaded HACD-TMAV showed ∼2.0-fold higher cytotoxicity against A549 cells compared to individual carriers and ∼4.5-fold higher cytotoxicity than by DON. Furthermore, HACD-TMAV-DON induced a ∼3.5-fold reduction in the size of 3D tumor spheroids of A549 cells. The enhanced anticancer effectiveness was attributed to starvation of the A549 cells of glutamine by dual targeting of glutamine metabolism and solute linked carrier family 1 member A5 (SLC1A5) through HA-linked CD44-mediated targeted delivery of DON. This led to over-production of reactive oxygen species (ROS) that induced apoptosis of cancer cells through downregulation of the PI3K/AKT/mTOR signaling cascade.

Hyaluronic acid-magnetic fluorescent polydopamine/gold-based fluorescent probe for bioimaging of CD44 over-expressed cancer cells

CD44 is a transmembrane glycoprotein (P-glycoprotein) that expressed in a large scale on the surface membrane of breast cancer cells. The CD44 receptor has been employed for various medial aims such as imaging, drug delivery, and etc. In the present work, the surface of citrate-capped gold nanoparticles (cit-AuNPs) was modified with magnetic polydopamine nanoparticles to provide fluorescent nanocomposite and amine groups for attachment to hyaluronic acid (HA) molecules. HA molecules have been bonded to the surface of fluorescent polydopamine nanoparticles (FPNPs) via the formation of amide bonds between carboxyl (COOH) group of HA and amine groups of the FPNPs. Due to the presence of the HA molecules, the MNPs-FPNPs/AuNPs/HA can attach to the CD44-overexpressed MCF-7 cells with high specificity and could be employed for bioimaging aims. Fluorescence microscopy was applied for bioimaging of the MNPs-FPNPs/AuNPs/HA internalized cancer cells. Obtained results offered that the MNPs-FPNPs/AuNPs/HA can especially and efficiently internalize to the cells and differentiate CD44-positive cancer cells and normal cells of HFFF-2 cells. Also, the MNPs-FPNPs/AuNPs/HA has a biocompatible nature with the toxic levels around 250 μg/mL levels. As a conclusion, the MNPs-FPNPs/AuNPs/HA is a good candidate for specific bioimaging applications of CD44−overexpressed MCF-7 cancer cells with high physicochemical stability and advantageous spectral features.

Sodium Butyrate Induces CRC Cell Ferroptosis via the CD44/SLC7A11 Pathway and Exhibits a Synergistic Therapeutic Effect with Erastin.

Human normal intestinal epithelial cell line FHT and colorectal tumor cell line HCT-116 were treated with NaB alone or in combination with different programmed cell death inhibitors. Cell activity was then assessed with MTT assays and PI staining; ferroptosis with Fe2+, glutathione (GSH), and lipid peroxidation assays; signaling pathway screening with PCR arrays; and CD44, SCL7A11, and GPX4 expression with Western blotting. A CD44-overexpressing HCT-116 cell line was constructed to determine the effect of the overexpression of CD44 on NaB-induced ferroptosis. The synergistic effect of co-treatment with NaB and Erastin was assessed by isobolographic analysis. NaB induced apoptosis and ferroptosis in HCT-116 cells but only induced low-level apoptosis in FHC cells. Moreover, NaB significantly increased intracellular Fe2+ and promoted GSH depletion and lipid peroxidation in HCT-116 cells. Ferroptosis-related qPCR array analysis identified CD44/SLC7A11 as a potential effector molecular of NaB-induced ferroptosis. NaB significantly inhibited the expression of CD44 and SLC7A11 in mouse CRC tissues. A CD44 overexpressed HCT-116 cell line was used to verify that CD44/SLC7A11 was a key signaling pathway that NaB-induced GSH depletion, lipid peroxidation accumulation, and ferroptosis in HCT-116 cells. Examination of whether NaB can increase the effect of ferroptosis agents showed that NaB, in combination with Erastin, a ferroptosis inducer, further promoted HCT-116 cell death and increased changes of ferroptosis markers. Our results suggest that NaB induces ferroptosis in CRC cells through the CD44/SLC7A11 signaling pathway and has synergistic effects with Erastin. These results may provide new insights into CRC prevention and the combined use of NaB and ferroptosis-inducing agents.

Programmable site-specific delivery of an alkaline phosphatase-activatable prodrug and a mitochondria-targeted cyclopeptide for combination therapy in colon cancer.

The design of advanced carriers that enable time- or stimulus-programmed drug release holds great promise to enhance the treatment efficacy in tumors. Here, hyaluronic acid (HA)-coated liposomes were designed to efficiently deliver multi-organelle-targeted and ALP/GSH dual-responsive prodrugs for combination therapy on colon tumors. In this system (designated CPTP/RA-HALipo), the unique natural cyclopeptide RA-V was linked covalently to a near-infrared (NIR) fluorophore through a disulfide linker, which was subsequently loaded in the cationic liposome core of CPTP/RA-HALipo, while the ALP-activatable phosphate CPT (CPTP) was encapsulated in the HA shell. In the tumor microenvironment, the HA shell of CPTP/RA-HALipo was partially degraded by HAase, thereby allowing the release of CPTP. The released phosphate prodrug CPTP was activated through hydrolysis of the phosphate esters by brush border-associated enzymes. The cationic liposome coated with the remaining HA could selectively enter CD44 overexpressed cells via receptor-mediated endocytosis into the lysosome, in which the acidic microenvironment degraded the liposomes to release the mitochondria-targeted theranostic agent RA-S-S-Cy. More significantly, the GSH-activatable NIR fluorescence of Cy5.5 made it possible to realize in vivo and in situ dynamic monitoring of drug release in a noninvasive manner. The organelle-specific and multi-stimuli responsive nanoparticles have shown precise control over drug delivery and release, leading to superior in vitro and/or in vivo anti-cancer efficacy. This approach represents a novel interactive drug delivery system that can synergistically differentiate the extracellular, cell membranal and intracellular targets to promote spatial and temporal control of drug release.

Cell-type-specific CRISPRization of mitochondrial DNA using bifunctional biodegradable silica nanoparticles.

We report cell-type-specific and CRISPR/Cas9-mediated mtDNA editing platform by using bifunctional biodegradable silica nanoparticles, which were capable of selective intracellular delivery to CD44-overexpressed cells and subsequent mitochondrial localization, followed by glutathione-responsive biodegradation and release of Cas9/sgRNA to realize precise mtDNA editing.

Design of Diselenide-Bridged Hyaluronic Acid Nano-antioxidant for Efficient ROS Scavenging to Relieve Colitis.

Overproduction of reactive oxygen species (ROS), a key characteristic of inflammatory bowel disease (IBD), is responsible for dysregulation of signal transduction, inflammatory response, and DNA damage, which ultimately leads to disease progression and deterioration. Thus, ROS scavenging has become a promising strategy to navigate IBD. Inspired by the targeting capability of hyaluronic acid (HA) to CD44-overexpressed inflammatory cells together with the redox regulation capacity of diselenide compounds, we developed an oral nanoformulation, i.e., diselenide-bridged hyaluronic acid nanogel (SeNG), with a view to treat colitis through a ROS scavenging mechanism. Our data demonstrated that SeNG specifically accumulated in colitis tissue that was mediated by highly efficient CD44-HA interaction. This has allowed us to demonstrate a significant anti-inflammatory effect in an acute colitis mouse model induced by dextran sulfate sodium and trinitrobenzenesulfonic acid. Mechanistically, we continued to show SeNG reduced the ROS level via both direct elimination and up-regulation of the Nrf2/HO-1 signal pathway. Collectively, our work provides proof-of-principle evidence for a SeNG-mediated nano-antioxidant strategy, by which colitis could be effectively managed.

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 significanceTumors 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.

Smart PdH@MnO2 Yolk-Shell Nanostructures for Spatiotemporally Synchronous Targeted Hydrogen Delivery and Oxygen-Elevated Phototherapy of Melanoma.

Hydrogen therapy, an emerging therapeutic strategy, has recently attracted much attention in anticancer medicine. Evidence suggests that hydrogen (H2) can selectively reduce intratumoral overexpressed hydroxyl radicals (•OH) to break the redox homeostasis and thereby lead to redox stress and cell damage. However, the inability to achieve stable hydrogen storage and efficient hydrogen delivery hinders the development of hydrogen therapy. Furthermore, oxygen (O2) deficiency in the tumor microenvironment (TME) and the electron-hole separation inefficiency in photosensitizers have severely limited the efficacy of photodynamic therapy (PDT). Herein, a smart PdH@MnO2/Ce6@HA (PHMCH) yolk-shell nanoplatform is designed to surmount these challenges. PdH tetrahedrons combine stable hydrogen storage and high photothermal conversion efficiency of palladium (Pd) nanomaterials with near-infrared-controlled hydrogen release. Subsequently, the narrow bandgap semiconductor manganese dioxide (MnO2) and the photosensitizer chlorin e6 (Ce6) are introduced into the PHMCH nanoplatform. Upon irradiation, the staggered energy band edges in heterogeneous materials composed of MnO2 and Ce6 can efficiently facilitate electron-hole separation for increasing singlet oxygen (1O2). Moreover, MnO2 nanoshells generate O2 in TME for ameliorating hypoxia and further improving O2-dependent PDT. Finally, the hyaluronic acid-modified PHMCH nanoplatform shows negligible cytotoxicity and selectively targets CD44-overexpressing melanoma cells. The synergistic antitumor performance of the H2-mediated gas therapy combined with photothermal and enhanced PDT can explore more possibilities for the design of gas-mediated cancer therapy.

Fe(II)-hydrazide coordinated all-active metal organic framework for photothermally enhanced tumor penetration and ferroptosis-apoptosis synergistic therapy

The combination of ferroptosis and apoptosis that act with different mechanisms holds enormous potential in cancer treatment. However, how to simply but effectively integrate the two modalities into a single platform is an enormous challenge. Herein, based on our newly discovered Fe(II)-hydrazide coordination self-assembly strategy, we design and develop an all-active amorphous metal organic framework (aMOF) for photothermally boosted ferroptosis-apoptosis synergistic anti-tumor therapy. The aMOF is prepared via one-pot co-assembly of doxorubicin (DOX), Fe2+ ions and 3,3′-dithiobis(propionohydrazide) (TPH) and subsequent decoration with TPH-functionalized hyaluronic acid. The obtained DOX@FeTH is amorphous in structure, and it exhibits favorable photothermal performance and displays pH/GSH/laser triple-responsive degradation behavior. The aMOF can be specifically internalized by CD44-overexpressed 4T1 cells and efficiently inhibit GPX4 activity via disulfide bond-mediated glutathione depletion, elevate intracellular H2O2 level by DOX-induced NOX4 activation, and consequently amplify lipid peroxidation with the assistance of self-supplied Fe2+, resulting in remarkable ferroptotic cell death. Meanwhile, the released DOX causes apoptotic cell death. Moreover, the aMOF-mediated hyperthermia can promote tumor penetration and augment the synergistic efficacy. Hence, the tumors are effectively suppressed by the synergistic treatment of DOX@FeTH with laser. This work provides a new strategy for fabricating aMOFs and opens a new horizon for tumor treatment.

CD44-Targeted Carriers: The Role of Molecular Weight of Hyaluronic Acid in the Uptake of Hyaluronic Acid-Based Nanoparticles

Nanotechnology offers advanced biomedical tools for diagnosis and drug delivery, stressing the value of investigating the mechanisms by which nanocarriers interact with the biological environment. Herein, the cellular response to CD44-targeted nanoparticles (NPs) was investigated. CD44, the main hyaluronic acid (HA) receptor, is widely exploited as a target for therapeutic purposes. HA NPs were produced by microfluidic platform starting from HA with different molecular weights (Mw, 280, 540, 820 kDa) by polyelectrolyte complexation with chitosan (CS). Thanks to microfluidic technology, HA/CS NPs with the same physical features were produced, and only the effects of HA Mw on CD44-overexpressing cells (human mesenchymal stem cells, hMSCs) were studied. This work provides evidence of the HA/CS NPs biocompatibility regardless the HA Mw and reveals the effect of low Mw HA in improving the cell proliferation. Special attention was paid to the endocytic mechanisms used by HA/CS NPs to enter hMSCs. The results show the notable role of CD44 and the pronounced effect of HA Mw in the NPs’ internalization. HA/CS NPs uptake occurs via different endocytic pathways simultaneously, and most notably, NPs with 280 kDa HA were internalized by clathrin-mediated endocytosis. Instead, NPs with 820 kDa HA revealed a greater contribution of caveolae and cytoskeleton components.

Versatile and Robust Method for Antibody Conjugation to Nanoparticles with High Targeting Efficiency.

The application of antibodies in nanomedicine is now standard practice in research since it represents an innovative approach to deliver chemotherapy agents selectively to tumors. The variety of targets or markers that are overexpressed in different types of cancers results in a high demand for antibody conjugated-nanoparticles, which are versatile and easily customizable. Considering up-scaling, the synthesis of antibody-conjugated nanoparticles should be simple and highly reproducible. Here, we developed a facile coating strategy to produce antibody-conjugated nanoparticles using ‘click chemistry’ and further evaluated their selectivity towards cancer cells expressing different markers. Our approach was consistently repeated for the conjugation of antibodies against CD44 and EGFR, which are prominent cancer cell markers. The functionalized particles presented excellent cell specificity towards CD44 and EGFR overexpressing cells, respectively. Our results indicated that the developed coating method is reproducible, versatile, and non-toxic, and can be used for particle functionalization with different antibodies. This grafting strategy can be applied to a wide range of nanoparticles and will contribute to the development of future targeted drug delivery systems.

Self-Assembly Cascade Reaction Platform for CD44 Positive Lung Cancer Therapy.

Lung cancer, as one of the most fatal cancers around the world, is responsible for the death of millions every year. Among various types of lung cancers, the ones overexpressing CD44 is usually associated higher cell proliferation with poorer prognosis. Therefore, finding a way to effectively treat CD44 positive lung cancer is urgently needed. Here in this study, negatively charged ultrasmall prussian blue nanoparticles (UPBNPs) was firstly synthesized and adsorbed to polyethyleneimine (PEI) together with glucose oxidase (Gox). Afterwards, the PEI was further complexed with hyaluronic acid (HA) to give a cascade reaction platform (HP/UPB-Gox) for CD44 positive lung cancer therapy. The HP/UPB-Gox with HA shell was able to positively target CD44 overexpressed A549 cells. Upon arriving at the tumor tissue, the Gox catalyzed the glucose of tumor to create H₂O₂, which further served as the substrate of UPBNPs, a peroxidase mimic, to finally give highly toxic hydroxyl radical (OH) for cancer therapy. Therefore, the cascade reaction formed between UPBNPs and Gox was expected to realize effective treatment on CD44 overexpressed lung cancer.

Targeted delivery of doxorubicin through CD44 aptamer to cancer cells.

Aim: The current investigation is focused on the targeted delivery of doxorubicin through CD44 aptamer-mediated active targeting to the human breast cancer cells. Methods: CD44 aptamer-doxorubicin (Apt-Dox) conjugates were developed by incubating different molar ratios of aptamer and doxorubicin. Cytotoxicity, selective intracellular accumulation and uptake of the Apt-Dox conjugates were analyzed to evaluate the efficacy of Apt-Dox conjugates. Results: Dox was efficiently conjugated with aptamer at 1:2 Apt-Dox molar ratios. Apt-Dox conjugate significantly inhibited the proliferation of CD44-overexpressing breast cancer cells, whereas negligible inhibition of cell proliferation was found in the control cells. Apt-Dox conjugate selectively internalized andaccumulatedin CD44-overexpressing cells. Conclusion: Apt-Dox conjugate selectively delivers doxorubicin to CD44-expressing cancer cells, thereby inhibiting selective cell proliferation and enhancing the targeted therapy.

Co-delivery of paclitaxel and STAT3 siRNA by a multifunctional nanocomplex for targeted treatment of metastatic breast cancer

Metastasis is one of the major causes of mortality in patients suffering from breast cancer. The signal transducer and activator of transcription 3 (STAT3) is closely related to cancer metastasis. Herein, a multifunctional nanocomplex was developed to simultaneously deliver paclitaxel (PTX) and STAT3 siRNA (siSTAT3) to inhibit tumor growth and prevent metastasis of breast cancer cells. PTX was encapsulated into the synthesized polyethyleneimine-polylactic acid-lipoic acid (PPL) micelle through hydrophobic interaction, while siSTAT3 was condensed onto polyethyleneimine through electrostatic interaction. The surface charge of the drug-loaded nanocomplex (siSTAT3PPLPTX) was then converted to negative by coating with hyaluronic acid (HA). The multifunctional nanocomplex (HA/siSTAT3PPLPTX) effectively entered CD44-overexpressed 4T1 cells via an active targeting mechanism. HA shell was degraded by the concentrated hyaluronidase in the endo/lysosome and the rapid drug release was triggered by the redox micro-environment of cytoplasm. Moreover, HA/siSTAT3PPLPTX showed enhanced cytotoxicity against tumor cells due to a synergistic effect of PTX and siSTAT3. The effective inhibition of tumor metastasis was confirmed by in vitro cell migration and invasion in 4T1 cells. More importantly, a superior antitumor efficacy was observed in orthotopic 4T1 tumor-bearing mice, with no side effects in major organs, and the lung metastasis was strongly inhibited in 4T1 metastasis model. In conclusion, the multifunctional nanocomplex provides a versatile platform for efficient treatment of metastatic cancer through tumor-targeted chemo-gene combined therapy. Statement of significanceMetastasis is one of the major causes of mortality in patients suffering from breast cancer. The signal transducer and activator of transcription 3 (STAT3) is closely related to cancer metastasis. In this study, a multifunctional nanocomplex co-loaded with paclitaxel (PTX) and STAT3 siRNA was constructed and characterized. The co-delivery system exhibited active tumor targeting, effective endo/lysosomal escape, and rapid intracellular drug release. Both in vitro and in vivo studies indicated that the nanocomplex could lead to superior tumor growth inhibition, as well as metastasis suppression by silencing expression of STAT3 and p-STAT3. This present study implies that the nanocomplex could be a potential platform for targeted treatment of metastatic cancer through chemo-gene combined therapy.

Hyaluronic Acid-Conjugated Nanoparticles for the Targeted Delivery of Cabazitaxel to CD44-Overexpressing Glioblastoma Cells.

In decades, the efficiency of glioma therapy is far from satisfaction due to the inability of most therapeutics to accumulate at the glioblastoma (GBM) site. Therefore, it is urgent to develop novel tumor-targeted delivery systems for more optimized and effective glioma treatment. In this study, hyaluronic acid modified MPEG-PDLLA polymer (HAML) nanoparticles were used to encapsulate the cabazitaxel (Cab), creating Cab loaded HAML nanoparticles (Cab/HAML NPs) for glioma therapy both in vitro and in vivo. MTT assay and apoptotic study indicated Cab/HAML NPs induced a significant cell growth inhibition and more apoptosis of C6 cells than free Cab in vitro. In vivo study showed that Cab/HAML NPs could significantly improve chemotherapeutic effect to C6 tumor-bearing rats compared with free Cab. The median survival rate of Cab/HAML NPs-treated groups (30 days) was remarkably longer than the other groups treated with control (20 days), free Cab (19 days) and Cab/ML NPs (26 days). Immunohistochemical analysis revealed that Cab/HAML NPs improved Cab's anti-tumor effect via improvement of tumor cell apoptosis, inhibition of tumor cell proliferation and a significant decrease in tumor angiogenesis. Together, our study suggested that Cab/HAML NPs might show promise for application to glioma therapy.