Folate Receptor Overexpressing Research Articles

Manganese-doped green tea-derived carbon quantum dots as a targeted dual imaging and photodynamic therapy platform.

In this work, manganese-doped carbon quantum dots (Mn-CQDs) have been synthesized through a one-pot hydrothermal method by using waste green tea. The Mn2+ dopants were introduced to impart magnetic resonance capability. Upon optimization of the experimental conditions, magnetofluorescent Mn-CQDs exhibit an excitation-dependent blue emission. The abundant functional groups on Mn-CQDs not only promote water solubility but also allow straightforward functionalization with amine groups. The amine-terminated Mn-CQDs were then subsequently conjugated to folic acid (FA) and chlorin e6 (Ce6) to obtain the Mn-CQDs@FA/Ce6 magnetofluorescent photodynamic therapy (PDT) agent. in vitro studies using three different cells indicated specific targeting of Mn-CQDs@FA/Ce6 to the overexpressing folate receptor human epithelial carcinoma cell line (HeLa) cancer cells. Furthermore, Mn-CQDs@FA/Ce6 enhanced magnetic resonance imaging (MRI) signal with an r2 /r1 ratio of 5.77. Favorably, by using the Mn-CQDs@FA delivery system, active Ce6 can reach the cellular interior while its red fluorescence (FL) and reactive oxygen species generation can be retained, as has been verified by confocal microscopy. in vitro cell viability studies verified the biocompatibility of Mn-CQDs@FA/Ce6 nanohybrid with no significant toxicity up to 500 ppm while PDT treatment with 5 min irradiation (671 nm, 1 W cm-2 ) was effective in killing >90% of cells. The light-triggered Mn-CQDs@FA/Ce6 multifunctional hybrid can serve as a dual-modal FL/MRI probe and as an efficient PDT agent to detect and eradicate cancer cells remotely.

Selectivity Enhancement of Paclitaxel Liposome Towards Folate Receptor-Positive Tumor Cells by Ligand Number Optimization Approach.

The present work aims to develop folate-targeted paclitaxel liposome (F-PTX-LIP), which will selectively target tumor cells overexpressing folate receptor (FR) and leave normal cells. Liposomes were prepared by thin-film hydration method followed by post-insertion of synthesized ligand 1,2-distearoyl-sn-glycero-phosphoethanolamine-polyethyleneglycol 2000-folic acid (DSPE-PEG2000-FA) on the outer surface of the liposome. The synthesized ligand was evaluated for in vivo acute toxicity in Balb/c mice. Developed liposomal formulations were characterized using transmission electron microscopy (TEM) and small-angle neutron scattering (SANS). We have investigated the effect of ligand number on cell uptake and cytotoxicity by confocal laser scanning microscopy (CLSM), competitive inhibition and 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) assay. Compared to lung adenocarcinoma cells (A549), uptake in human ovarian carcinoma cells (SKOV3) was 2.2- and 1.2-fold higher for liposome with 480 and 240 ligand number respectively. Competitive inhibition experiment shows that prior incubation of SKOV3 cells with free folic acid significantly reduced the cell uptake of F-PTX-LIP with 480 ligand number (480 F-PTX-LIP) by 2.6-fold. 480 F-PTX-LIP displays higher cytotoxicity than free drug and PTX liposome. Moreover, it specifically targets the cells with higher folate receptor expression. Optimized 480 F-PTX-LIP formulation can be potentially useful for the treatment of folate receptor-positive tumors.

Targeted exosome-encapsulated erastin induced ferroptosis in triple negative breast cancer cells.

Ferroptosis is an iron‐dependent, lipid peroxide‐driven cell death caused by inhibition of the cystine/glutamate transporter, which is of importance for the survival of triple‐negative breast cancer (TNBC) cells. Erastin is a low molecular weight chemotherapy drug that induces ferroptosis; however, poor water solubility and renal toxicity have limited its application. Exosomes, as drug delivery vehicles with low immunogenicity, high biocompatibility and high efficiency, have attracted increasing attention in recent years. Herein, we developed a formulation of erastin‐loaded exosomes labeled with folate (FA) to form FA‐vectorized exosomes loaded with erastin (erastin@FA‐exo) to target TNBC cells with overexpression of FA receptors. The characterization, drug release, internalization and anti–tumor effect in vitro of erastin@FA‐exo were determined. Erastin@FA‐exo could increase the uptake efficiency of erastin into MDA‐MB‐231 cells; compared with erastin@exo and free erastin, erastin@FA‐exo has a better inhibitory effect on the proliferation and migration of MDA‐MB‐231 cells. Furthermore, erastin@FA‐exo promoted ferroptosis with intracellular depletion of glutathione and reactive oxygen species overgeneration. Western blot analyses revealed that erastin@FA‐exo suppressed expression of glutathione peroxidase 4 (GPX4) and upregulated expression of cysteine dioxygenase (CDO1). We conclude that targeting and biocompatibility of exosome‐based erastin preparations provide an innovative and powerful delivery platform for anti–cancer therapy.

Folate Receptor Overexpression in Human and Canine Meningiomas—Immunohistochemistry and Case Report of Intraoperative Molecular Imaging

Meningiomas are well-encapsulated benign brain tumors and surgical resection is often curative. Nevertheless, this is not always possible due to the difficulty of identifying residual disease intraoperatively. We hypothesized that meningiomas overexpress folate receptor alpha (FRα), allowing intraoperative molecular imaging by targeting FRα with a near-infrared (NIR) dye. To determine FRα expression in both human and canine meningioma cohorts to prepare for future clinical studies. Present a case study of a meningioma resection with intraoperative NIR fluorescence imaging. Tissue samples of 27 human meningioma specimens and 7 canine meningioma specimens were immunohistochemically stained for FRα along with normal dura, skeletal muscle, and kidney tissue. We then enrolled a patient with a pituitary adenoma and tuberculum sella meningioma in a clinical trial in which the patient received an infusion of folate-linked, NIR fluorescent dye prior to surgery. In the cohort of human meningiomas, 9 WHO grade I, 12 grade II, and 6 grade III tumors were identified. Eighty-nine percent of WHO grade I, 67% of grade II, and 50% of grade III tumors overexpressed FRα. In the 7 canine meningioma samples, 100% stained positively for FRα. Both human and canine normal dura from autopsy samples demonstrated no evidence of FRα overexpression. In the case study, the meningioma demonstrated a high NIR signal-to-background-ratio of 4.0 and demonstrated strong FRα immunohistochemistry staining. This study directly demonstrates FRα overexpression in both human and canine meningiomas. We also demonstrate superb intraoperative imaging of a meningioma using a FRα-targeting dye.

Folate-coated, long-circulating and pH-sensitive liposomes enhance doxorubicin antitumor effect in a breast cancer animal model

Long circulating pH-sensitive liposomes have been shown to effectively deliver doxorubicin (DOX) to tumors and reduce its toxic effects. Folic acid receptors are upregulated in a wide variety of solid, epithelial tumors, including breast cancer. In order to improve liposomal endocytosis and antitumor activity, folic acid has been added to nanoparticles surfaces to exploit overexpression of folate receptors in tumor cells. The purpose of this study was to evaluate the antitumor activity in vitro and in vivo of long circulating pH-sensitive folate-coated DOX-loaded liposomes (SpHL-DOX-Fol) in a 4T1 breast cancer model system in vitro and in vivo. Biodistribution studies were performed and in vivo electrocardiographic parameters were evaluated. A higher tumor uptake for radiolabeled SpHL-Fol (99mTc-SpHL-Fol) 4 h after intravenous administration was observed in comparision with non-folate-coated liposomes (99mTc-SpHL). Antitumor activity showed that SpHL-DOX-Fol treatment led to a 68% growth arrest and drastically reduce pulmonary metastasis foci. Additionally, eletrocardiographic parameters analysis revealed no dispersion in the QT and QTc interval was observed in liposomal treated mice. In summary, this novel multifunctional nanoplatform deomonstrated higher tumor uptake and antitumor activity. SpHL-DOX-Fol represents a drug delivery platform to improve DOX tumor delivery and reduce dose-limiting toxicity.

Tumor-targeting photodynamic therapy based on folate-modified polydopamine nanoparticles.

BackgroundPhotodynamic therapy (PDT), a clinical anticancer therapeutic modality, has a long history in clinical cancer treatments since the 1970s. However, PDT has not been widely used largely because of metabolic problems and off-target phototoxicities of the current clinical photosensitizers.PurposeThe objective of the study is to develop a high-efficiency and high-specificity carrier to precisely deliver photosensitizers to tumor sites, aiming at addressing metabolic problems, as well as the systemic damages current clinical photosensitizers are known to cause.MethodsWe synthesized a polydopamine (PDA)-based carrier with the modification of folic acid (FA), which is to target the overexpressed folate receptors on tumor surfaces. We used this carrier to load a cationic phthalocyanine-type photosensitizer (Pc) and generated a PDA-FA-Pc nanomedicine. We determined the antitumor effects and the specificity to tumor cell lines in vitro. In addition, we established human cancer-xenografted mice models to evaluate the tumor-targeting property and anticancer efficacies in vivo.ResultsOur PDA-FA-Pc nanomedicine demonstrated a high stability in normal physiological conditions, however, could specifically release photosensitizers in acidic conditions, eg, tumor microenvironment and lysosomes in cancer cells. Additionally, PDA-FA-Pc nanomedicine demonstrated a much higher cellular uptake and phototoxicity in cancer cell lines than in healthy cell lines. Moreover, the in vivo imaging data indicated excellent tumor-targeting properties of PDA-FA-Pc nanomedicine in human cancer-xenografted mice. Lastly, PDA-FA-Pc nanomedicine was found to significantly suppress tumor growth within two human cancer-xenografted mice models.ConclusionOur current study not only demonstrates PDA-FA-Pc nanomedicine as a highly potent and specific anticancer agent, but also suggests a strategy to address the metabolic and specificity problems of clinical photosensitizers.

Facile synthesis of multi-walled carbon nanotube via folic acid grafted nanoparticle for precise delivery of doxorubicin.

The motive of work was to develop a multi-walled carbon nanoplatform through facile method for transportation of potential anticancer drug doxorubicin (DOX). Folic acid (FA)-ethylene diamine (EDA) anchored and acid functionalised MWCNTs were covalently grafted with DOX via π-π stacking interaction. The resultant composite was corroborated by 1H NMR, FTIR, XRD, EDX, SEM, and DSC study. The drug entrapment efficiency of FA-conjugated MWCNT was found high and stability study revealed its suitability in biological system. FA-EDA-MWCNTs-DOX conjugate demonstrated a significant in vitro anticancer activity on human breast cancer MCF-7 cells. MTT study revealed the lesser cytotoxicity of folate-conjugated MWCNTs. The obtained results demonstrated the targeting specificity of FA-conjugate via overexpressed folate receptor deemed greater scientific value to overcome multidrug protection during cancer therapy. The proposed strategy is a gentle contribution towards development of biocompatible targeted drug delivery and offers potential to address the current challenges in cancer therapy.

Bovine Serum Albumin-Templated Synthesis of Manganese-Doped Copper Selenide Nanoparticles for Boosting Targeted Delivery and Synergistic Photothermal and Photodynamic Therapy.

Multifunctional nanohybrids integrating diagnostic imaging with photodynamic or photothermal therapy in a single agent feature the next generation of on-demand nanomedicine to meet the challenges in cancer therapy. In the present study, bovine serum albumin (BSA) protein through one pot biomimetic mineralization at its metal binding site synthesized and stabilized manganese-doped copper selenide nanoparticles (Mn:CuSe) with excellent biocompatibility, near-infrared absorption, water solubility, and rich functional groups for further bioconjugation. Mn doping not only imparted the magnetic resonance imaging (MRI) function to the Mn:CuSe@BSA but also enhanced its heat generation ability. By taking advantage of BSA's extraordinary ligand binding capacity, folic acid (FA) and chlorin e6 (Ce6) were then conjugated onto the BSA corona to construct the Mn:CuSe@BSA-FA-Ce6 nanohybrid for specific targeting of overexpressed folate receptor cancer cells. The obtained theranostic agent exhibited dual MRI signal enhancement and synergistic photothermal/photodynamic therapy (PTT/PDT) effect, which was demonstrated in vitro on HeLa cells. As a consequence, dual modal therapy with 1 min PDT laser irradiation doubled cell killing efficiency compared to the single PDT treatment. Having better efficacy regarding biocompatibility and synergistic light-activation therapy, the Mn:CuSe@BSA-FA-Ce6 nanohybrid holds the promise for image-guided cancer therapy.

Platinated porphyrin tailed with folic acid conjugate for cell-targeted photodynamic activity

For a precisely targeted photosensitizer, we designed and prepared a new platinated porphyrin (Pt-Por-FA) by Pt-Por tailed with folic acid (FA). The intercalation mode of Pt-Por-FA binding to ct-DNA was confirmed by UV–vis and fluorescent spectra. The singlet oxygen generation of Pt-Por-FA was evaluated through 2′, 7′-dichlorofluorescin (DCFH) method. The cellular uptake and the intracellular localization of Pt-Por-FA were studied upon A549 and HeLa cells through confocal laser scanning microscope. The results showed that the red fluorescence of porphyrin conjugate observed in HeLa cells [folate receptor (FR)–positive] was significantly stronger than that of A549 cells (FR-negative), indicating that Pt-Por-FA could target specifically the cancer cells with overexpression of FR via FR-mediated endocytosis. Pt-Por-FA successfully localized in the lysosomes of cancer cells, but Pt-Por without FA did not. Moreover, the cytotoxicity against HeLa and MDA-MB-231 cells was measured by MTT assay. The results demonstrated that Pt-Por-FA had minor cytotoxicity in the dark, but showed a obviously improving toxicity in presence of light. At the concentration of 20 μM Pt-Por-FA, the cell viabilities were only 12.0% and 26.4% with the IC50 values down to 5 μm and 12 μm against HeLa and MDA-MB-231 cells, respectively. It suggests that Pt-Por-FA could be a precisely targeted photosensitizer with over-expression of a folate receptor.

Flower-like curcumin-loaded folic acid-conjugated ZnO-MPA- βcyclodextrin nanostructures enhanced anticancer activity and cellular uptake of curcumin in breast cancer cells.

Non-spherical structures are beneficial to advance drug delivery effectiveness compared with common spherical ones, due to increased drug loading capability, improved bonding to a vascular wall, enhanced cellular uptake efficacy and prolonged circulation times. In this study, flower-like Zinc oxide-βcyclodextrin (βCD) nanostructures functionalized by 3-mercaptopropionic acid (MPA) as a non-spherical delivery system was successfully synthesized for aqueous delivery of curcumin (CUR) to enhance its targeting, bioavailability, and release profile. Terminal carboxyl functional groups were used for the conjugation of folic acid (FA) with the aim of active targeting to folate overexpressing breast cancer cells. The in vitro experimental study and mathematical modeling of CUR release revealed a sustained release with Fickian diffusion as the major release mechanism. MTT, colony formation and Annexin-V FITC/PI assays showed the superior anticancer effect of the system compared to free CUR against breast cancer cell line MDA-MB-231 by promoting the apoptotic respond with no cytotoxic effect on HEK293 normal cells. The efficacy of targeting strategy with FA moieties was demonstrated using the augmented cellular uptake of the FA-conjugated system on overexpressed folate receptor alpha (FRα) cells (MDA-MB-468 breast cancer cell line). Furthermore, loading of CUR to the delivery systems significantly lowered the MIC values (2.5 to 5-fold) against S. aureus and E. coli the infections of which are serious problems in cancer patients. According to the results of this study, the system can serve as a promising non-spherical delivery vehicle for enhancing bioavailability and targeting of hydrophobic anticancer agents in the future.

In vitro anticancer activity of folate-modified docetaxel-loaded PLGA nanoparticles against drug-sensitive and multidrug-resistant cancer cells

BackgroundPoly(lactic-co-glycolic acid) (PLGA) is a biodegradable and biocompatible polymer which is widely used as a matrix to incorporate therapeutic agents. The anticancer activity of targeted folate-modified docetaxel-loaded PLGA nanoparticles (F–NP–Doc) was studied in vitro.MethodsNanoparticles were prepared by a single-emulsion solvent-evaporation technique and characterized by physico-chemical methods. Cell survival was measured by the MTT assay and the sulforhodamine B assay. Folate receptor α expression, particle uptake and apoptosis were assessed by flow cytometry.ResultsFolate-modified docetaxel-loaded PLGA nanoparticles showed high anticancer activity in vitro against HeLa cervical carcinoma cells and MCF7 breast adenocarcinoma cells overexpressing folate receptors. Targeted F–NP–Doc nanoparticles were more active compared to free docetaxel and non-targeted NP–Doc nanoparticles; in contrast, the activity of targeted nanoparticles against human fibroblasts (negative control) was significantly lower. F–NP–Doc particles, like free docetaxel, induced apoptosis in cancer cells. F–NP–Doc, but not unmodified docetaxel-loaded PLGA nanoparticles, reversed multidrug resistance of MCF7R breast adenocarcinoma cells. High antitumor activity of F–NP–Doc has also been proven in in vivo experiments.ConclusionsThe summarized experimental data brought us to the conclusion that the incorporation of docetaxel into the targeted PLGA nanoparticles dramatically improves its selectivity against cancer cells.

In vitro anti-cancer efficacy of multi-functionalized magnetite nanoparticles combining alternating magnetic hyperthermia in glioblastoma cancer cells

Localized hyperthermia and the targeted release of the chemotherapy drug are one of the most challenging problems in chemo-hyperthermia therapy. In the present study, magnetite nanoparticles as a carrier of Temozolomide (TMZ) functionalized with folic acid-ligand (TMZ-MNP-FA) were designed and developed for targeted chemotherapy and radiofrequency hyperthermia of cancer cells.Nanoparticles were synthesized and characterized for hydrodynamic diameter, zeta potential, morphology, drug loading capacity, and in vitro RF-triggered release. Their cytotoxicity and efficacy as targeted drug delivery systems were evaluated in both cancer and normal cells and the therapeutic efficacy was analyzed on the C6 glioblastoma cancer cells. The C6 cells were treated with the nanoparticles and subjected to an alternating magnetic field (AMF) to reach a typical hyperthermia temperature of 43 °C. Then induction of apoptotic cells and the proliferation capacity of cancer cells were evaluated.The in vitro release studies exhibited that the drug release from TMZ-loaded magnetite nanoparticles was minimal at 37 °C but was noticeably boosted under an AMF irradiation. The developed targeted magnetite nanoparticles revealed higher cytotoxic effect and cellular uptake in folate-receptor overexpressing C6 cancer cells compared to OLN-93 normal cells. All results showed that combined magnetite chemo-hyperthermia (AMF + TMZ-MNP-FA) treatment was significantly more efficacious in cancer cells than hyperthermia, chemotherapy, or chemo-hyperthermia treatments (P < 0.0001).In conclusion, TMZ-MNP-FA had a key role to convert the externally delivered radiofrequency energy to heat in cancer cells. Additionally, localized hyperthermia triggered a TMZ release from the nanocarriers that resulted in cancer cell damage with synchronizing hyperthermia and chemotherapy.

Single-Layer Assembly of Multifunctional Carboxymethylcellulose on Graphene Oxide Nanoparticles for Improving in Vivo Curcumin Delivery into Tumor Cells.

Nanodrug delivery systems are considered as promising therapeutic platforms to convey drugs to tumor cells. In this study, a single layer of carboxymethylcellulose (CMC) and poly N-vinylpyrrolidone (PVP) was cross-linked through disulfide bond and deposited on graphene oxide nanoparticles (GO NPs) using layer-by-layer technique. Overexpression of folate receptors on tumor cells is a great hallmark for drug delivery systems; though the NPs were functionalized by monoclonal folic acid antibody (FA) using polyethylene glycol (PEG) as linker. The mean diameter of synthesized nanoparticles was 60 nm. Curcumin was encapsulated within CMC layer with high encapsulation capacity of 94%. In vitro investigation showed 87% curcumin release at simulated tumor environment. Curcumin loaded FA modified CMC/PVP GO NPs showed high inhibition of 76 and 81% against Saos2 and MCF7 cell lines in vitro. In vivo investigations on 4T1 bearing breast cancer mice model exhibited 76% antitumor efficiency via active targeting mechanism of folate mediated transport without any significant side effect. Immunohistochemistry and immunofluorescence analyses showed enhanced antiangiogenesis, apoptosis and tumor growth inhibition.

Multifunctional Oligonucleotide-Functionalized Conjugated Oligomer Nanoparticles for Targeted Cancer Cell Imaging and Therapy.

A novel and multifunctional oligonucleotide-functionalized conjugated oligomer nanoparticle (CON) is developed for effective cancer cell imaging and therapy by integration of fluorescence imaging, target recognition, photodynamic therapy (PDT), and chemotherapy. The CON itself possesses the high fluorescence emission efficiency for imaging and can generate reactive oxygen species for PDT. Due to its excellent biocompatibility, easy functional modification, and efficient drug loading and release ability, oligonucleotides enable the CON to be functionalized in many forms. For the target recognition, the CONs are functionalized with oligonucleotides labeled with folate molecules, which can specifically bind the CONs to the tumor cells overexpressing folate receptors. Moreover, the designed oligonucleotide on the CON hybridizes with its complementary sequence to form double-stranded DNA, which enables a sequence-specific loading with doxorubicin for chemotherapy. For different situations, the therapy of chemotherapy and PDT can be used solely or combinatorially. Therefore, this study provides a facile strategy for the multifunctional modification of CONs with oligonucleotides and opens a new avenue for targeted cell imaging and tumor treatment.

Gadolinium (III) oxide nanoparticles coated with folic acid-functionalized poly(β-cyclodextrin-co-pentetic acid) as a biocompatible targeted nano-contrast agent for cancer diagnostic: in vitro and in vivo studies.

In this study, a novel targeted MRI contrast agent was developed by coating gadolinium oxide nanoparticles (Gd2O3 NPs) with β-cyclodextrin (CD)-based polyester and targeted by folic acid (FA). The developed Gd2O3@PCD-FA MRI contrast agent was characterized and evaluated in relaxivity, in vitro cell targeting, cell toxicity, blood compatibility and in vivo tumor MR contrast enhancement. In vitro cytotoxicity and hemolysis assays revealed that Gd2O3@PCD-FA NPs haveno significant cytotoxicity after 24 and 48h against normal human breast cell line (MCF-10A) at concentration of up to 50µg Gd+3/mL and havehigh blood compatibility at concentration of up to 500µg Gd+3/mL. In vitro MR imaging experiments showed that Gd2O3@PCD-FA NPs enable targeted contrast T1- and T2-weighted MR imaging of M109 as overexpressing folate receptor cells. Besides, the in vivo analysis indicated that the maximum contrast-to-noise ratio (CNR) of tumor in mice increased after injection of Gd2O3@PCD-FA up to 5.89 ± 1.3 within 1h under T1-weighted imaging mode and reduced to 1.45 ± 0.44 after 12h. While CNR increased up to maximum value of 1.98 ± 0.28 after injection of Gd2O3@PCD within 6h and reduced to 1.12 ± 0.13 within 12h. The results indicate the potential of Gd2O3@PCD-FA to serve as a novel targeted nano-contrast agent in MRI.

131I-labeled PEG and folic acid co-functionalized graphene quantum dots for tumor-targeted imaging

In this study, we successfully synthesized polyethylene glycol (PEG) and folic acid (FA) co-functionalized graphene quantum dots (GQDs) to improve the biocompatibility and tumor-targeting ability of GQDs simultaneously, and labeled GQDs–PEG–FA with 131I for biological behavior evaluation. The in vitro properties, biodistribution and SPECT imaging of 131I-GQDs–PEG–FA were investigated. The uptake of 131I-GQDs–PEG–FA at tumor sites can be clearly examined via SPECT imaging, which can ascribe to enhanced permeability and retention effect and active targeting effect of FA to folate receptors. The results indicate that 131I-GQDs–PEG–FA can be used as a radioactive probe for detection of tumor cells overexpressing folate receptor.

Folic Acid-Functionalized Gold Nanorods for Controlled Paclitaxel Delivery: In Vitro Evaluation and Cell Studies.

Short gold nanorods were synthesized (average length 28.08nm, average aspect ratio 3.54), which were functionalized with folic acid (FA) and 8-mercaptooctanoic acid (MOA) or 11-mercaptoundecanoic acid (MDA) and loaded with paclitaxel (PCT). FA was conjugated to the nanorods in order to render them targetable for cancer cells overexpressing folate receptors whereas MOA or MDA was attached on the nanorods in order to generate extra hydrophobic areas for entrapment of hydrophobic drugs such as PCT in the nanorods and in order to provide free carboxylic groups, which would allow for the conjugation of drug or other biofunctional molecules to the nanorods. The functionalized gold nanorods (GNRs-MOA-FA and GNRs-MDA-FA) did not exhibit any significant degree of aggregation in cell culture medium and blood plasma even after a prolonged incubation period of 7days, indicating the adequate colloidal stability of the nanorods in these media. The functionalized nanorods exhibited satisfactory entrapment efficiency (around 40%) for PCT and released less than 25% of their PCT content in phosphate buffer pH 7.4 in 48h. PCT entrapment efficiency was a little higher and PCT release rate a little lower in the GNRs-MOA-FA. Molecular analysis (qPCR) was used to find out that the MDA-MB-231 cancer cell line expresses the folate receptor (FL1R) whereas the MCF-7 cancer cell line does not. The PCT-loaded GNRs-MOA-FA were more cytotoxic than the PCT-loaded GNRs-MOA nanorods against the MDA-MB-231 cells, which probably relates to the higher uptake of the GNRs-MOA-FA nanorods by these cells. The opposite was true in the case of the MCF-7 cells.

Cytotoxicity of 5-ALA-conjugated bismuth oxidenanoparticles on KB cell line

Introduction: In recent years, bismuth-based nanomaterials have been widely used in medical researches as imaging, drug delivery and x-ray radiosensitizing agents. Due to their anti-microbial effects against Helicobacter pylori (HP), bismuth colloidal compounds are used to treat various types of diseases such as chronic gastritis. Despite their advantages, bismuth-based compounds have shown many toxic effects in humans. There are few studies on cytotoxicity effects of bismuth (ΙΙΙ) oxide (Bi2O3) nanoparticles (NPs). Based on the natural high affinity of folate for the folate receptor protein (FR), which is commonly expressed on the surface of many human cancers, folate-drug conjugates bind tightly to the FR and trigger cellular uptake via endocytosis. Therefore, we aimed to investigate the cytotoxicity effects of 5-ALA-conjugated Bi2O3 NPs, 5-ALA-folate-conjugated Bi2O3 NPs and free 5-ALA on oral squamous carcinoma cell line (KB cells) for the first time. 5-ALA is used in photo dynamic detection and photodynamic surgery of cancer. Being a precursor of a photosensitizer, 5-ALA is also used as an add on agent for photodynamic therapy. Materials and Methods: Bi2O3 NPs were synthesized and conjugated with folate and 5- aminolevulinic acid (5-ALA). KB cells were cultured monolayer and incubated with 10, 20, 50, 100 and 200 μg/ml concentrations of free 5-ALA, 5-ALA-folate-conjugated Bi2O3 NPs and 5-ALA-conjugated Bi2O3 NPs for 24 hours. The survival of the cells obtained after 24 h of incubation with the materials using MTT assay. Results: Bi2O3 NPs were synthesized (~20 nm) and conjugated to folate and (5-ALA). Results indicated that the significant cellular death were noted at the concentrations more than of 50 μg/ml for all compounds that cell viability reduced to 37%, 49% and 63% in groups receiving 5-ALA-folate-conjugated NPs, 5-ALA-conjugated Bi2O3 NPs and free 5-ALA, respectively. The cytotoxicity of the materials on KB cells also increased with increasing concentrations of synthesized NPs. Conclusion:5-ALA-folate-conjugated NPs, 5-ALA-conjugated Bi2O3 NPs and free 5-ALA were easily taken up by the cells and showed cytotoxic effects at high concentrations. Folic acid conjugation facilitates selective targeting of the KB cells with the overexpression of the folate receptors and improves internalization of the drugs through receptor-mediated endocytosis

Kinetics of cell death triggered photothermally using folate-conjugated gold nanoparticles and various laser irradiation conditions in cancer cells

Introduction: In this study, we explore in detail cell-specific targeting efficacy of nano-photo-thermal therapy (NPTT) method and the resulting responses that are induced by variable laser intensities and exposure times in cancer cells to induce selective apoptosis. We delineate the synthesis of a high-yielding synthetic F-AuNPs by tailoring the surface of gold nanoparticles with folic acid to enhance cell selectivity and specificity. Materials and Methods: For this purpose, synthesized F-AuNPs treated cells were irradiated with various laser intensities and exposure duration. Both KB cancer cells, as a folate receptor over-expressing cell line, and L929 normal cells, with low level of folate receptors were used. Following various regimes of NPTT, Cytotoxicity was assessed by MTT assay and comparison of induced apoptosis and necrosis in population of cells were depicted by Annexin/PI staining. Results: We report no significant cytotoxicity difference between KB and L929 cell lines at concentrations up to 40 μM of F-AuNPs. Moreover, no significant cell lethality occurred for various laser irradiation conditions. However, in photothermal therapy, the viability of KB and L929 cells was 57% and 83%, respectively. Flow cytometry clearly revealed the kinetics of cell death. The majority of cancer cell death was related to apoptosis (41% apoptosis of 43% overall cell death). Conclusion: Together, these findings confirm that F-AuNPs based NPTT can either induces cell death via apoptosis or necrosis. The main factor determining whether a cell will die due to apoptosis or necrosis on-demand with PTT depends on laser heating level. Our main target must be to only trigger apoptosis during PTT by using suitable irradiation conditions. As a result, folate targeting ability of the F-AuNPs and laser energy threshold to induce selective apoptosis in cancer cells were shown.

Multiplexed In Vivo Imaging Using Size-Controlled Quantum Dots in the Second Near-Infrared Window.

PbS/CdS core/shell quantum dots (QDs) that emit at the second near-infrared (NIR-II, 1000-1700 nm) window are synthesized. The PbS seed size and CdS shell thicknesses are carefully controlled to produce bright and narrow fluorescence that are suitable for multiplexing. A polymer encapsulation yields polymer-encapsulated NIR-II QDs (PQDs), which provides the QDs with long-term fluorescence stability over a week in biological media. Exploiting the simple bioconjugation capability of PQDs, folic acids are conjugated to PQDs that can efficiently label folate receptor overexpressing cell lines. The PQDs afford multiplexed and nearly real-time longitudinal whole-body in vivo imaging. Two NIR-II QD probes are prepared: folic acid-conjugated PQDs (FA-PQDs) emitting at 1280 nm and unconjugated PQDs emitting at 1080 nm. The two PQDs are engineered to have compact and similar hydrodynamic sizes. A mixture of the folic acid-conjugated PQD and unconjugated PQDs is injected intravenously into a tumor-xenografted mouse, and the signals from them are monitored. This NIR-II whole-body imaging with the two PQDs provides precise evaluation of the active ligand-assisted tumor-targeting capability of the FA-PQD probe because the hydrodynamic size control of the two PQDs effectively eliminates effects from the size-dependent accumulations by permeations and retentions in tumors.