Folate Receptor-mediated Endocytosis Research Articles

Abstract 482: Advancing treatment for metastatic triple negative breast cancer: Liposomal oncolytic adenovirus as a novel neoadjuvant therapy

Abstract Introduction: Adenovirus type-5 (Ad) is considered a prominent viral vector in cancer therapy due to its modifiability for the selective lysis of cancer cells. However, challenges are posed in Ad delivery to cancers lacking coxsackievirus and adenovirus receptors (CARs). In response to this limitation, Ad-encapsulated DOTAP-folate liposomes were developed, which improved Ad delivery and heightened therapeutic efficacy through membrane fusion and folate receptor-mediated endocytosis. Methods: The 4T1 mammary carcinoma model, a CAR-negative triple-negative breast cancer (TNBC) cell line (ER-, PR-, HER2-), resistant to adenoviral infection, was utilized for studying the comparative in vitro transduction of green fluorescent protein (GFP)-expressing Ad (Ad-GFP). The study assessed Ad-GFP with and without DOTAP-folate liposomal encapsulation at a multiplicity of infection (MOI) of 50. Additionally, an oncolytic adenovirus, Ad-hTERT, with a human telomerase promoter, underwent liposomal encapsulation. CAR-negative 4T1 GFP-expressing cells and CAR-positive MDA-MB-231-GFP human breast adenocarcinoma TNBC cells were transduced in vitro at MOI 100 with Ad-hTERT, both with and without DOTAP-folate liposomal encapsulation. Results: CAR-negative 4T1 cells exhibited superior Ad-GFP transduction when encapsulated in DOTAP-folate liposomes, compared to the unencapsulated form (p < 0.001). For oncolytic adenovirus Ad-hTERT, encapsulation resulted in 100% cell lysis within 24 hours in 4T1-GFP cells, contrasting with 13% with unencapsulated Ad-hTERT (P < 0.0001). In CAR-positive MDA-MB-231-GFP TNBC cells, encapsulated Ad-hTERT showed enhanced efficacy, resulting in 100% cell lysis within 24 hours compared to 75% with unencapsulated Ad-hTERT (P < 0.001). Discussion: DOTAP-folate liposomal encapsulation enhances the efficacy of oncolytic Ad-hTERT in both CAR-negative and CAR-positive TNBC cells, establishing it as an optimal therapy for tumors with CAR heterogeneity. Ongoing in vivo studies with Balb/C immune-competent mice and the 4T1 tumor model will assess the effectiveness of encapsulation through intratumoral administration. This approach may extend the recurrence-free period post-surgical tumor removal. Citation Format: Jaimin R. Shah, Tao Dong, Abraham Phung, Sarah L. Blair, Omonigho Aisagbonhi, William C. Trogler, Andrew C. Kummel. Advancing treatment for metastatic triple negative breast cancer: Liposomal oncolytic adenovirus as a novel neoadjuvant therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 482.

Appraisal of folate functionalized bosutinib cubosomes against hepatic cancer cells: In-vitro, In-silico, and in-vivo pharmacokinetic study

Targeted therapies enhance the efficacy of tumour screening and management while lowering side effects. Multiple tumours, including liver cancer, exhibit elevated levels of folate receptor expression. This research attempted to develop surface-functionalised bosutinib cubosomes against hepatocellular carcinoma. The novelty of this work is the anti-hepatic action of bosutinib (BST) and folic acid-modified bosutinib cubosomes (BSTMF) established through proto-oncogene tyrosine-protein kinase (SrC)/ focal adhesion kinase(FAK), reactive oxygen species (ROS), mitochondrial membrane potential (MMP), and cell cytotoxicity. Later, the in-vivo pharmacokinetics of BSTMF were determined for the first time. The strong affinity of folic acid (FA) for folate receptors allows BSTMF to enter cells via FA receptor-mediated endocytosis. The particle size of the prepared BSTMF was 188.5 ± 2.25 nm, and its zeta potential was −20.19 ± 2.01 mV, an encapsulation efficiency of 90.31 ± 3.15 %, and a drug release rate of 76.70 ± 2.10 % for 48 h. The surface architecture of BSTMF was identified using transmission electron microscopy (TEM) and Atomic force microscopy (AFM). Cell-line studies demonstrated that BSTMF substantially lowered the viability of Hep G2 cells compared to BST and bosutinib-loaded cubosomes (BSTF). BSTMF demonstrated an elevated BST concentration in tumour tissue than in other organs and also displayed superior pharmacokinetics, implying that they hold potential against hepatic cancers. This is the first study to show that BSTMF may be effective against liver cancer by targeting folate receptors and triggering SrC/FAK-dependent apoptotic pathways. Multiple parameters demonstrated that BSTMF enhanced anticancer targeting, therapeutic efficacy, and safety in NDEA-induced hepatocellular carcinoma.

Liposomes Coated with Novel Synthetic Bifunctional Chitosan Derivatives as Potential Carriers of Anticancer Drugs.

In this study, liposomes coated with novel multifunctional polymers were proposed as an innovative platform for tumor targeted drug delivery. Novel Folic acid-Cysteine-Thiolated chitosan (FTC) derivatives possessing active targeting ability and redox responsivity were synthesized, characterized, and employed to develop FTC-coated liposomes. Liposomes were characterized for size, surface charge and drug encapsulation efficiency before and after coating. The formation of a coating layer on liposomal surface was confirmed by the slight increase in particle size and by zeta-potential changes. FTC-coated liposomes showed a redox-dependent drug release profile: good stability at physiological conditions and rapid release of liposome-entrapped calcein in presence of glutathione. Moreover, the uptake and cytotoxic activity of doxorubicin-loaded FTC-coated liposomes was evaluated on murine B16-F10 and human SKMEL2 melanoma cancer cells. Results demonstrated enhanced uptake and antitumor efficacy of FTC-coated liposomes compared to control chitosan-coated liposomes in both cancer lines, which is attributed to higher cellular uptake via folate receptor-mediated endocytosis and to triggered drug release by the reductive microenvironment of tumor cells. The proposed novel liposomes show great potential as nanocarriers for targeted therapy of cancer.

Targeted delivery and apoptosis induction of CDK-4/6 inhibitor loaded folic acid decorated lipid-polymer hybrid nanoparticles in breast cancer cells

Targeted drug delivery is an advanced approach for active targeting of tumor that can enhance the concentration of the drug at the site of action and reduce the off-target toxicity and non-specific effects of the drug. Folate receptors (FR) are membrane-bound surface proteins, over-expressed in numerous solid tumors, folate and folate conjugates bind to FR with higher affinity. In the present investigation, we fabricated Folic acid (FA) decorated Palbociclib loaded lipid-polymer hybrid nanoparticles (FA-PLPHNPs) using quality by design (QbD) approach and evaluated its anti-cancer activity in folate receptor-positive breast cancer cell lines. 1HNMR, ATR-FTIR spectroscopic techniques confirmed the formation of DSPE-PEG-FA ligand. The optimized FA-PLPHNPs formulation exhibited 143.36 ± 5.24 nm, 0.172 ± 0.004, −16.84 ± 0.27 mV, and 93.12 ± 0.43 % of particle size, PDI, zeta potential and % entrapment efficiency, respectively. The FA-PLPHNPs exhibited an approximately 9, 11-fold reduction in IC50 values than free Palbociclib in MCF-7 and MDA-MB-231 cells at 48 h. The role of FA in targeting breast cancer was studied by means of a receptor-blocking assay, and concluded that FA-PLPHNPs were internalized into MCF-7 and MDA-MB-231 cells by folate receptor-mediated endocytosis. FA-PLPHNPs showed higher anti-cancer efficiency and caused enhanced reactive oxygen species generation, apoptosis (Acridine orange/ ethidium bromide dual staining and Annexin V/PI staining), reduced cell migration, and colony formation. Thus, the fabricated Palbociclib-loaded FA-conjugated lipid polymer hybrid nanoparticles could act as a potential nanocarrier for the treatment of breast cancer.

Tumor-activated targetable photothermal chemotherapy using IR780/zoledronic acid-containing hybrid polymeric nanoassemblies with folate modification to treat aggressive breast cancer.

To effectively treat aggressive breast cancer by tumor-activated targetable photothermal chemotherapy, in this work, folate (FA)-modified hybrid polymeric nanoassemblies (HPNs) with a poly(ethylene glycol) (PEG)-detachable capability are developed as vehicles for tumor-targeted co-delivery of IR780, a lipophilic photothermal reagent, and zoledronic acid (ZA), a hydrophilic chemotherapy drug. Through hydrophobic interaction-induced co-assembly, IR780 molecules and ZA/poly(ethylenimine) (PEI) complexes were co-encapsulated into a poly(lactic-co-glycolic acid) (PLGA)-rich core stabilized by the amphiphilic FA-modified D-α-tocopheryl poly(ethylene glycol) succinate (FA-TPGS) and acidity-sensitive PEG-benzoic imine-octadecane (C18) (PEG-b-C18) conjugates. The developed FA-ZA/IR780@HPNs with high ZA and IR780 payloads not only showed excellent colloidal stability in a serum-containing milieu, but also promoted IR780-based photostability and photothermal conversion efficiency. Furthermore, for FA-ZA/IR780@HPNs under simulated physiological conditions, the premature leakage of IR780 and ZA molecules was remarkably declined. In a mimetic acidic tumor microenvironment, the uptake of FA-ZA/IR780@HPNs by FA receptor-overexpressed 4T1 breast cancer cells was remarkably promoted by PEG detachment combined with FA receptor-mediated endocytosis, thus effectively hindering migration of cancer cells and augmenting the anticancer efficacy of photothermal chemotherapy. Notably, the in vivo studies demonstrated that the FA-ZA/IR780@HPNs largely deposited at 4T1 tumor sites and profoundly suppressed tumor growth and metastasis without severe systemic toxicity upon near infrared (NIR)-triggered IR780-mediated hyperthermia integrated with ZA chemotherapy. This work presents a practical strategy to treat aggressive breast tumors with tumor-triggered targetable photothermal chemotherapy using FA-ZA/IR780@HPNs.

Ionic Liquids Nanoliposomes Based on Targeted and Active Permeability for Enhanced Combination Chemotherapy Efficiency

Tumor microenvironment severely restricts the delivery of chemotherapy drugs. The microenvironment responsive nanoparticles often have complex designs with hampered clinical translatability. Here, we show a kind of ionic liquids (ILs) with soybean lecithin (SL) as cation, folic acid (FA) as anion, in particular, it could formulate nanoliposome by film evaporation method to deliver cis-Diamineplatinum (II) dichloride (cisplatin, Cis) and doxorubicin hydrochloride (DOX). These special ILs liposome could target tumor cells via folate receptor-mediated endocytosis by enhancing the cellular uptake, and significantly improve the deep permeability by actively infiltrating throughout the tumor tissue owing to the special noncovalent bond between SL–FA ILs with cell membrane. Moreover, ILs liposomes improve delivery efficiency of Cis and DOX and enhance the combined chemotherapeutic effect. The simple preparation process of the ILs nanoliposome should facilitate the clinical transformation of nanodrugs.

Folic acid-coupled bovine serum albumin-modified magnetic nanocomposites from quantum-sized Fe3O4 and layered double hydroxide for actively targeted delivery of 5-fluorouracil

The development of multifunctional magnetic nanocomposites as a drug delivery system for cancer therapy is highly desirable in current nanomedicine. Herein, folic acid-bovine serum albumin conjugate (FA-BSA) was modified on nanocomposites by combining quantum-sized Fe3O4 and layered double hydroxide (LDH) to obtain a novel FA-BSA/Fe3O4@LDH for the delivery of the anticancer drug 5-Fluorouracil (5-Fu). The prepared nanocomposites showed good dispersibility, colloidal stability, magnetic property and erythrocyte compatibility. FA-BSA/Fe3O4@LDH/5-Fu showed pH responsiveness, with both the amount and duration of release of FA-BSA/Fe3O4@LDH/5-Fu being significantly higher in pH 5.0 release medium than in pH 7.4 release medium. The cellular experiments implied that no significant cytotoxicity of FA-BSA/Fe3O4@LDH, particularly due to the presence of FA-BSA, which further enhanced the biocompatibility of the nanocomposite. Furthermore, FA-BSA/Fe3O4@LDH/5-Fu could specifically target the 2D HepG2 cells model and 3D hepatoma cell microspheres model in vitro, and efficient internalization through folate receptor-mediated endocytosis, showing excellent anti-cancer cell activity in a concentration-dependent manner. Therefore, the constructed FA-BSA/Fe3O4@LDH was able to provide a potential novel multifunctional nanocomposite for magnetic-targeting drug delivery and pH-responsive release of drugs to enhance the efficiency of cancer therapy.

Folic acid-decorated vitamin E Poly(ethylene glycol) monoplatinum ester with disulfide bond as theranostic nanoparticle for drug resistant tumor diagnosis and treatment

Vitamin E Poly(ethylene glycol) monoplatinum ester (TPGS) nanoparticles have attracted much attention in recent years for overcome multidrug resistance. Herein, a well-defined folic acid (FA)-conjugated and disulfide bond-linked polymer (FA-SS-TPGS) was synthesized. These polymer nanoparticles were utilized as theranostic agents for tumor-targeted magnetic resonance imaging (MRI) and chemotherapy. By loading doxorubicin (DOX) and superparamagnetic iron oxide (SPIO) particles into TPGS nanoparticles, FA-SS-TPGS@DOX/SPIO nanoparticles are obtained. In vitro drug release studies revealed that under a reducing environment in the presence of glutathione (GSH), approximately 100% of the doxorubicin (DOX) was released from the disulfide bond-linked theranostic nanoparticles within 24 h. DOX and SPIO were efficiently delivered into HepG2-ADM cells due to the folate receptor-mediated endocytosis process of the nanoparticles. Additionally, the presence of glutathione (GSH) triggered the cleaving of the disulfide bonds, further facilitating the delivery of DOX and SPIO into the cells. Furthermore, the FA-SS-TPGS @DOX-SPIO nanoparticles exhibited strong MRI contrast enhancement properties. In conclusion, FA-SS-TPGS@DOX/SPIO are potential nanoparticles for tumor-targeted MRI and chemotherapy, which can also overcome multidrug resistance.

The folate-linked chitosan-coated Kaempferol/HSA nano-transporters (FCKH-NTs) as the selective apoptotic inducer in human MCF-7 breast cancer cell line

Background Kaempferol, the natural bioactive flavonoid, has been utilized as an efficient anti-breast cancer compound. In the current study, the Kaempferol’s cellular uptake and its aqueous solubility were improved by using human serum albumin (HSA) as the Kaempferol adjuvant and encapsulating it with the folate-linked chitosan polymer to evaluate the apoptotic, activity of the novel-formulated Kaempferol in human MCF-7 breast cancer cells. Methods The folate-linked chitosan-coated Kaempferol/HSA nano-transporters (FCKH-NTs) were synthesized and characterized using FTIR, FESEM, DLS, and Zeta potential analysis. The nano-transporters’ selective cytotoxicity was studied by applying an MTT assay on the cancerous MCF-7 cells compared with normal HFF cell lines. Cell death type determination was determined by analyzing the expression of apoptotic (BAX and Cas-8) and anti-apoptotic genes (BCL2 and NF-κB). The FCKH-NTs apoptotic activity was verified by studying the flow cytometry and AO/PI staining results. Result The 126-nm FCKH-NTs (PDI = 0.282) selectively induced apoptotic death in human MCF-7 breast cancer cells by up-regulating the BAX, Nf- κB, and Cas-8 gene expression. The apoptotic activity of FCKH-NTs was verified by detecting the SubG1-arrested cancer cells and increased apoptotic bodies in AO/PI staining images. Conclusion The FCKH-NTs exhibited a selective-cytotoxic impact on human MCF-7 breast cancer cells compared with normal HFF cells, which can be due to the folate receptor-mediated endocytosis mechanism of the nano-transporters. Therefore, the FCKH-NTs have the potential to be used as a selective anti-breast cancer compound.

Folate-modified carboxymethyl chitosan-based drug delivery system for breast cancer specific combination therapy via regulating mitochondrial calcium concentration

Although various drug delivery systems that regulated Ca2+ concentration has been developed for tumor therapy, their application still presented significant challenges due to the complex preparation and introduction of a large number of inorganic molecules that might cause serious toxic effects. To solve these problems, a folate-functionalized carboxymethyl chitosan (CMCS)/calcium phosphate hybrid nanoparticle (CF/CaP) with Ca2+ production was designed to treat breast cancer combined with the Ca2+ inhibitory effect of encapsulated curcumin (Cur). It was demonstrated that the optimal CF/CaP nanoparticles loaded with Cur (C@CF/CaP) were spherical nanoparticles, which exhibited a smaller size at about 179 nm than non-targeted nanoparticles with size at about 234 nm. C@CF/CaP had good biocompatibility, high stability and acid responsive drug release. Compared with the neutral environment, the cumulative release of Cur was >70 % after culture for 36 h at pH 5.0. Compared with non-targeted nanoparticles, C@CF/CaP could specifically target tumor tissues and then enter tumor cells through folate receptor-mediated endocytosis. C@CF/CaP could cause mitochondrial Ca2+ overload, trigger the mitochondrial apoptotic pathway, destroy the mitochondrial structure and finally have good anti-tumor efficiency. The results proved that Ca2+ nanomodulators based on CMCS might provide a potential organelle targeting strategy for cancer therapy.

Synthesis and evaluation of folate-mediated targeting and poly (β-amino ester)-mediated pH-responsive delivery system of riccardin D based on the O-carboxymethylated chitosan micelles

This study aimed to combine the active targeting function of folate (FA) receptor-mediated endocytosis with the pH-responsive drug delivery of poly (ethylene glycol)-grafted-poly (−amino ester) copolymers (PEG-PAE) in cancer targeting therapy. Herein, O-carboxymethylated chitosan (OCMC) was grafted with hydrophobic deoxycholic acid (DOCA). Further, PEG-PAE and FA-conjugated DOCA modified OCMC were synthesized to develop the potential cancer-targeted carrier (PEG-PAE-DOMC-FA), for which the structure was investigated by 1H NMR and FTIR. Then riccardin D (RD) was successfully loaded for tumor-targeted drug delivery. The particle size, zeta potential, encapsulating efficiencies, and loading content profiles of PEG-PAE-DOMC-FA/RD showed a strong dependence on the environmental pH values. The cumulative release of PEG-PAE-DOMC-FA/RD at pH 5.0 (90.63 %) was higher than pH 7.4 (51.12 %), which also indicated the pH sensitivity. Moreover, a lower IC50 and higher coumarin-6 uptake were found because of the folate-receptor-mediated endocytosis. In pharmacokinetic study, PEG-PAE-DOMC-FA/RD significantly improved the mean retention time (MRT) and AUC(0-∞) from 7.89 h and 36.1 mg/L·h of control group to 10.03 h and 123.8 mg/L·h. In the xenograft mice model, stronger antitumor efficacy and lower toxicity were confirmed. In conclusion, the multi-functional micelles could be considered as a promising vehicle for delivering hydrophobic drugs to tumors.

Intracellular and extracellular enzymatic responsive micelle for intelligent therapy of cancer.

Recently, the incidence of cancer keeps increasing, seriously endangers human health, and has evolved into the main culprit of human death. Conventional chemotherapeutic drugs, such as paclitaxel and doxorubicin (DOX), have some disadvantages, including low therapeutic effect, poor water solubility, high toxic side effects, short blood circulation time in the body, and so on. To improve the anti-tumor effect of the drug in vivo and reduce its side effects on the body, researchers have designed and developed a variety of responsive nanocarriers. In this work, we synthesized D-α-tocopherol polyethylene glycol 3350 succinate (TPGS3350)-Gly-Pro-Leu-Gly-Val-Arg (GPLGVR)-DOX (TPD) prodrugs in response to extracellular enzymes of matrix metalloproteinase (MMP-9) in the tumor microenvironment and FA-Asp-Glu-Val-Asp (DEVD)-DOX (FPD) prodrugs responsive to intracellular enzymes of caspase-3. Then, intracellular and extracellular enzyme-responsive TPD&FPD micelles with DOX (TPD&FPD&D) were successfully prepared through dialysis method. The outer layer of TPGS3350 can prolong the blood circulation time of micelles in vivo, followed by accumulation of micelles at tumor tissue through enhanced permeability and retention (EPR) effect. The peptide of GPLGVR can be cleaved by MMP-9 enzymes to remove the outer layer of TPGS3350, exposing the targeting molecule of folate, and then the micelles are engulfed by tumor cells through folate receptor-mediated endocytosis. After entering the tumor cells, the free DOX loaded in the micelles is released, which induces tumor cell apoptosis to activate caspase-3 in the cells, cutting the peptide DEVD to accelerate the intracellular release of the DOX, which further enhances cytotoxicity to improve antitumor effect.Electronic Supplementary MaterialSupplementary material () is available in the online version of this article at 10.1007/s12274-022-4967-1.

Construction of a Stimuli-Responsive DNAzyme-Braked DNA Nanomachine for the Amplified Imaging of miRNAs in Living Cells and Mice

Construction of a Stimuli-Responsive DNAzyme-Braked DNA Nanomachine for the Amplified Imaging of miRNAs in Living Cells and Mice

Delivery of acetogenin-enriched Annona muricata Linn leaf extract by folic acid-conjugated and triphenylphosphonium-conjugated poly(glycerol adipate) nanoparticles to enhance toxicity against ovarian cancer cells

The study demonstrated the fabrication of new poly(glycerol adipate) (PGA) nanoparticles decorated with folic acid (FOL-PGA) and triphenylphosphonium (TPP-PGA) and the potential on the delivery of acetogenin-enriched Annona muricata Linn leaf extract to ovarian cancer cells. FOL-PGA and TPP-PGA were successfully synthesized and used to fabricate FOL-decorated nanoparticles (FOL-NPs) and FOL-/TPP- decorated nanoparticles (FOL/TPP-NPs) by blending two polymers at a mass ratio of 1:1. All nanoparticles had small size of around 100 nm, narrow size distribution and high negative surface charge about −30 mV. The stable FOL/TPP-NPs showed highest drug loading of 14.9 ± 1.9% at 1:5 ratio of extract to polymer and reached to 35.8 ± 2.1% at higher ratio. Both nanoparticles released the extract in a biphasic sustained release manner over 5 days. The toxicity of the extract to SKOV3 cells was potentiated by FOL-NPs and FOL/TPP-NPs by 2.0 – 2.6 fold through induction of cell apoptosis. FOL/TPP-NPs showed lower IC50 and higher cellular uptake as compared to FOL-NPs. FOL-NPs exhibited folate receptor-mediated endocytosis. FOL/TPP-NPs provided more advantages than FOL-NPs in terms of stability in physiological fluid, uptake efficiency and targeting ability to mitochondria and showed a promising potential PGA platform for targeted delivery of herbal cytotoxic extracts.

Co-delivery of paclitaxel (PTX) and docosahexaenoic acid (DHA) by targeting lipid nanoemulsions for cancer therapy

Breast cancer is one of the most common types of cancer in female patients with high morbidity and mortality. Multi-drug chemotherapy has significant advantages in the treatment of malignant tumors, especially in reducing drug toxicity, increasing drug sensitivity and reducing drug resistance. The objective of this research is to fabricate lipid nanoemulsions (LNs) for the co-delivery of PTX and docosahexaenoic acid (DHA) with folic acid (FA) decorating (PTX/DHA-FA-LNs), and investigate the anti-tumor activity of the PTX/DHA-FA-LNs against breast cancer both in vitro and in vivo. PTX/DHA-FA-LNs showed a steady release of PTX and DHA from the drug delivery system (DDS) without any burst effect. Furthermore, the PTX/DHA-FA-LNs exhibited a dose-dependent cytotoxicity and a higher rate of apoptosis as compared with the other groups in MCF-7 cells. The cellular uptake study revealed that this LNs were more readily uptaken by MCF-7 cells and M2 macrophages in vitro. Additionally, the targeted effect of PTX/DHA-FA-LNs was aided by FA receptor-mediated endocytosis, and its cytotoxicity was proportional to the cellular uptake efficiency. The anti-tumor efficiency results showed that PTX/DHA-FA-LNs significant inhibited tumor volume growth, prolonged survival time, and reduced toxicity when compared with the other groups. These results indicated that DHA increases the sensitivity of tumor cells and tumor-associated macrophages (ATM2) to PTX, and synergistic effects of folate modification in breast cancer treatment, thus PTX/DHA-FA-LNs may be a promising nanocarrier for breast cancer treatment.

Folic Acid-Decorated β-Cyclodextrin-Based Poly(ε-caprolactone)-dextran Star Polymer with Disulfide Bond-Linker as Theranostic Nanoparticle for Tumor-Targeted MRI and Chemotherapy.

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

Dual-modified nanoparticles overcome sequential absorption barriers for oral insulin delivery

The efficacy of oral insulin drug delivery is seriously hampered by multiple gastrointestinal barriers, especially transepithelial barriers, including apical endocytosis, lysosomal degradation, cytosolic diffusion and basolateral exocytosis. In this study, a functional nanoparticle (PG-FAPEP) with dual-modification was constructed to sequentially address these important absorption obstacles for improved oral insulin delivery. The dual surface decorations folate and charge-convertible tripeptide endowed PG-FAPEP with the ability to target the apical and basolateral sides of enterocytes, respectively. After fast diffusion across the mucus layer, PG-FAPEP could be efficiently internalized into epithelial cells via a folate receptor-mediated pathway and subsequently became positively charged in acidic lysosomes due to the surface tripeptide, triggering the proton sponge effect to escape lysosomes. When entering the cytosolic medium, PG-FAPEP was converted to neutral charge again, attenuating intracellular adhesion, and gained improved motility toward the basolateral side. Finally, the tripeptide helped PG-FAPEP recognize the proton-coupled oligopeptide transporter (PHT1) in the basolateral membrane, boosting intact exocytosis across intestinal epithelial cells. The in vivo studies further verified that PG-FAPEP could traverse the intestinal epithelium by folate receptor-mediated endocytosis, lysosomal escape, and PHT1-mediated exocytosis, exhibiting a high oral insulin bioavailability of 14.3% and a prolonged hypoglycemic effect. This formulation addresses multiple absorption barriers on demand with a simple dual-modification strategy. Therefore, these features allow PG-FAPEP to unleash the potential of oral macromolecule delivery.

Laser photo-thermal therapy of epithelial carcinoma using pterin-6-carboxylic acid conjugated gold nanoparticles.

Gold nanoparticles functionalized with folic acid toward the internalization into cancer cells have received considerable attention recently. Folic acid is recognized by folate receptors, which are overexpressed in several cancer cells; it is limited in normal cells. In this work, pterin-6-carboxylic acid is proposed as an agonist of folic acid since the pterin-6-carboxylic acid structure has a pterin moiety, the same as folic acid that is recognized by the folate receptor. Here a simple photochemical synthesis of gold nanoparticles functionalized with pterin-6-carboxylic acid is studied. These conjugates were used to cause photothermal damage of HeLa cells irradiating with a diode laser of 808nm. Pterin-6-carboxylic acid-conjugated gold nanoparticles caused the death of the cell after near-infrared irradiation, dose-dependently. These results indicate a possible internalization of AuNPs via folate receptor-mediated endocytosis due to the recognition or interaction between the folate receptors of HeLa cells and pterin, P6CA.

Selenium Nanoparticles in Folate-Targeted Delivery of the pCMV-Luc DNA Reporter Gene

Background: Selenium, an essential micronutrient, has been studied for decades for its anticancer properties. Selenium nanoparticles (SeNPs) have now emerged as an interesting alternative for drug and gene delivery. Aims: We aimed to demonstrate in proof of principle, the potential use of SeNPs in targeted pCMVLuc DNA (pDNA) delivery in vitro. Objectives: To chemically synthesize, characterize and evaluate the transgene expression of functionalized SeNPs in five human cell lines. Methods: SeNPs were synthesized via chemical reduction, coated with chitosan (Ch) and a targeting moiety, folic acid (FA). All nanoparticles were characterized by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), UV-vis and Fourier transform infra-red (FTIR) spectroscopy. Nanoparticle:pDNA interactions were assessed using the electrophoretic mobility shift, dye displacement and nuclease protection assays. The MTT and Luciferase reporter gene assays were used to determine cytotoxicity and transgene expression, respectively, in the human colorectal adenocarcinoma (HT-29 and Caco-2), breast adenocarcinoma (MCF-7), oral epidermoid/cervical carcinoma contaminant (KB) and the embryonic kidney (HEK293) cells. Results: Homogenous nanoparticles of 60-70 nm were able to successfully bind, compact and protect the pDNA from enzyme digestion. Low cytotoxicity was observed in all cells, except for the MCF-7 cells, which could be attributed to apoptosis and necrosis. Luciferase gene expression was highest for the targeted nanocomplexes in the folate-receptor rich KB cell line, confirming nanocomplex uptake through folate receptor-mediated endocytosis. Conclusion: This study opens a new avenue for synergistic treatment of cancer, combining selenium’s bioactivity and its carrier potential for therapeutic gene delivery.

Targeted Gold Nanohybrids Functionalized with Folate-Hydrophobic-Quaternized Pullulan Delivering Camptothecin for Enhancing Hydrophobic Anticancer Drug Efficacy.

This study presented a green, facile and efficient approach for a new combination of targeted gold nanohybrids functionalized with folate-hydrophobic-quaternized pullulan delivering hydrophobic camptothecin (CPT-GNHs@FHQ-PUL) to enhance the efficacy, selectivity, and safety of these systems. New formulations of spherical CPT-GNHs@FHQ-PUL obtained by bio-inspired strategy were fully characterized by TEM, EDS, DLS, zeta-potential, UV-vis, XRD, and ATR-FTIR analyses, showing a homogeneous particles size with an average size of approximately 10.97 ± 2.29 nm. CPT was successfully loaded on multifunctional GNHs@FHQ-PUL via intermolecular interactions. Moreover, pH-responsive CPT release from newly formulated-CPT-GNHs@FHQ-PUL exhibited a faster release rate under acidic conditions. The intelligent CPT-GNHs@FHQ-PUL (IC50 = 6.2 μM) displayed a 2.82-time higher cytotoxicity against human lung cancer cells (Chago-k1) than CPT alone (IC50 = 2.2 μM), while simultaneously exhibiting less toxicity toward normal human lung cells (Wi-38). These systems also showed specific uptake by folate receptor-mediated endocytosis, exhibited excellent anticancer activity, induced the death of cells by increasing apoptosis pathway (13.97%), and arrested the cell cycle at the G0-G1 phase. The results of this study showed that the delivery of CPT by smart GNHs@FHQ-PUL systems proved to be a promising strategy for increasing its chemotherapeutic effects.