GLUT1-mediated selective tumor targeting with fluorine containing platinum(II) glycoconjugates

Unlocking the power of sugar: carbohydrate ligands as key players in nanotherapeutic-assisted targeted cancer therapy

Cancer cells need as much as 40-times more sugar than their normal cell counterparts. This sugar demand is attained by the excessive expression of inimitable transporters on the surface of cancer cells, driven by their voracious appetite for carbohydrates. Nanotechnological advances drive research utilizing ligand-directed therapeutics and diverse carbohydrate analogs. The precise delivery of these therapeutic cargos not only mitigates toxicity associated with chemotherapy but also reduces the grim toll of mortality and morbidity among patients. This in-depth review explores the potential of these ligands in advanced cancer treatment using nanoparticles. It offers a broader perspective beyond the usual ways we deliver drugs, potentially changing the way we fight cancer.

Synthesis and Biological Evaluation of a Novel Sugar-Conjugated Platinum(II) Complex Having a Tumor-Targeting Effect

We designed and synthesized a novel platinum complex conjugated with 2-fluorinated 2-deoxyglucoside, named FGC-Pt, to capitalize on the Warburg effect and metabolic trapping properties of [18F]2-deoxy-2-fluoro-d-glucose ([18F]FDG). Then, we conducted comprehensive in vitro and in vivo studies to evaluate the effects of FGC-Pt. In vitro cytotoxicity assays using HeLa cells revealed that FGC-Pt exhibited concentration-dependent cytotoxicity, even though its cytotoxic effect was less pronounced than that of cisplatin. In the evaluation of in vivo biodistribution in mice, platinum concentration in tumors and major organs (muscle, bone, blood, liver, and kidney) and the ratio of platinum concentration in tumors to major organs following the tail vein injection of FGC-Pt and cisplatin suggest that FGC-Pt is more retained in tumors than in other organs and tends to accumulate in tumors more than cisplatin. Furthermore, an in vivo assessment of the antitumor effect conducted in A549 cell-bearing mice demonstrated that FGC-Pt possesses substantial potential as an antitumor agent. It exhibited a tumor growth-inhibitory effect comparable to that of cisplatin while inducing lower toxicity, as evidenced by lower weight loss after administration. Herein, we successfully produced a novel compound with a tumor-growth-inhibitory effect comparable to that of cisplatin and low toxicity.

Carbohydrate effect of novel arene Ru(II) phenanthroline-glycoconjugates on metastatic biological processes

Novel water-soluble half-sandwich ruthenium(II) polypyridyl-glycoconjugates [Ru(p-cymene)Cl{N-(1,10-phenanthroline-5-yl)-β-glycopyranosylamine}][Cl] (glycopyranosyl = d-glucopyranosyl (1), D-mannopyranosyl (2), L-rhamnopyranosyl (3) and l-xylopyranosyl (4)) have been synthesized and fully characterized. Their behaviour in water under physiological conditions has been studied by nuclear magnetic resonance spectroscopy, revealing their hydrolytic stability. Interactions of the novel compounds with duplex-deoxiribonucleic acid (dsDNA) were investigated by different techniques and the results indicate that, under physiological pH and saline conditions, the metal glycoconjugates bind DNA in the minor groove and/or through external, electrostatic interactions, and by a non-classical, partial intercalation mechanism in non-saline phosphate buffered solution. Effects of compounds 1-4 on cell viability have been assessed in vitro against two human cell lines (androgen-independent prostate cancer PC-3 and non-tumorigenic prostate RWPE-1), showing moderate cytotoxicities, with IC50 values higher than those found for free ligands [N-(1,10-phenanthroline-5-yl)-β-glycopyranosylamine] (glycopyranosyl = d-glucopyranosyl (a), D-mannopyranosyl (b), L-rhamnopyranosyl (c) and l-xylopyranosyl (d)) or corresponding metal-aglycone. Cell viability was assayed in the presence and absence of the glucose transporters (GLUTs) inhibitor [N4-{1-(4-cyanobenzyl)-5-methyl-3-(trifluoromethyl)-1H-pyrazol-4-yl}-7-fluoroquinoline-2,4-dicarboxamide] (BAY-876), and the results point to a negligible impact of the inhibition of GLUTs on the cytotoxicity caused by Ru(II) compounds 1-4. Remarkably, glycoconjugates 1-4 potently affect the migration pattern of PC-3 cells, and the wound healing assay evidence that the presence of the carbohydrate and the Ru(II) center is a requisite for the anti-migratory activity observed in these novel derivatives. In addition, derivatives 1-4 strongly affect the matrix metalloproteinase MMP-9 activities of PC-3 cells, while proMMP-2 and especially proMMP-9 were influenced to a much lesser extent.

Ligand Chemistry in Antitumor Theranostic Nanoparticles

ConspectusTheranostic nanoparticles' potential in tumor treatment has been widely acknowledged thanks to their capability of integrating multifaceted functionalities into a single nanosystem. Theranostic nanoparticles are typically equipped with an inorganic core with exploitable physical properties for imaging and therapeutic functions, bioinert coatings for improved biocompatibility and immunological stealth, controlled drug-loading-release modules, and the ability to recognize specific cell type for uptake. Integrating multiple functionalities in a single nanosized construct require sophisticated molecular design and precise execution of assembly procedures. Underlying the multifunctionality of theranostic nanoparticles, ligand chemistry plays a decisive role in translating theoretical designs into fully functionalized theranostic nanoparticles. The ligand hierarchy in theranostic nanoparticles is usually threefold. As they serve to passivate the nanoparticle's surface, capping ligands form the first layer directly interfacing with the crystalline lattice of the inorganic core. The size and shape of nanoparticles are largely determined by the molecular property of capping ligands so that they have profound influences on the nanoparticles' surface chemistry and physical properties. Capping ligands are mostly chemically inert, which necessitates the presence of additional ligands for drug loading and tumor targeting. The second layer is commonly utilized for drug loading. Therapeutic drugs can either be covalently conjugated onto the capping layer or noncovalently loaded onto nanoparticles via drug-loading ligands. Drug-loading ligands need to be equally versatile in properties to accommodate the diversity of drugs. Biodegradable moieties are often incorporated into drug-loading ligands to enable smart drug release. With the aid of targeting ligands which usually stand the tallest on the nanoparticle surface to seek and bind to their corresponding receptors on the target, theranostic nanoparticles can preferentially accumulate at the tumor site to attain a higher precision and quantity for drug delivery. In this Account, the properties and utilities of representative capping ligands, drug-loading ligands, and targeting ligands are reviewed. Since these types of ligands are often assembled in close vicinity to each other, it is essential for them to be chemically compatible and able to function in tandem with each other. Relevant conjugation strategies and critical factors with a significant impact on ligands' performance on nanoparticles are discussed. Representative theranostic nanoparticles are presented to showcase how different types of ligands function synergistically from a single nanosystem. Finally, the technological outlook of evolving ligand chemistry on theranostic nanoparticles is provided.

Cisplatin conjugation with an exopolysaccharide extracted from Lactobacillus gasseri potentiates its efficacy and attenuates its toxicity

The development of newer cisplatin analogs is constantly being investigated owing to its low solubility, poor pharmacokinetics, and dose-related toxicity. In order to address the limitations of current cisplatin therapy, the present study was undertaken. Cisplatin conjugation with an exopolysaccharide extracted from Lactobacillus gasseri (LG-EPS) showed remarkably enhanced and selective anticancer activity by targeting tumor cells overexpressing glucose transporter 1 (GLUT1). The EPS-cisplatin complex exhibited a 600-fold increase in aqueous solubility with a better pharmacokinetic profile (longer half-life) in comparison to cisplatin. Cell viability assay and western blotting demonstrated a strong correlation between the cytotoxicity profile and GLUT1 expressions in different cell lines. The concentration of DNA-bound platinum was also found to be significantly higher in EPS-cisplatin-treated cells. Quercetin, a competitive inhibitor of GLUTs, was shown to prevent this selective uptake of EPS-cisplatin complex. Surprisingly, EPS-cisplatin complex showed an exceptionally safer profile (4 times the maximum tolerated dose of cisplatin) in the acute toxicity study and was also more efficacious against the xenograft mice model. The study suggests that this green glycoconjugation can be an effective and safer strategy to broaden the therapeutic potential of anti-cancer drugs in general and cisplatin in particular.

ID-Checker Technology for the Highly Selective Macroscale Delivery of Anticancer Agents to the Cancer Cells

Cancer cells deploy several glucose transport protein (GLUT) channels on the cell membranes to increase glucose uptake. Cancer cells die within 24 h in the absence of glucose. Thus, preventing the deployment of GLUT channels can deprive them of glucose, resulting in apoptosis within 24 h. Herein, we developed the ID-Checker with a glucose tag that ensures its highly specific macroscale delivery of anticancer agents to the cancer cells through the GLUT channels. ID-Checker presented here showed IC50 values of 0.17-0.27 and 3.34 μM in cancer and normal cell lines, respectively. ID-Checker showed a selectivity index of 12.5-20.2, which is about 10-20 times higher than that of known anticancer agents such as colchicine. ID-Checker inhibits the microtubule formation, which results in the prevention of the deployment of GLUT channels in 6 h and kills the cancer cells within 24 h without any damage to normal cells.

Introduction of Fluorine into Antitumor-Active Dinuclear Platinum(II) Complexes Leads to Modulation of In Vivo Antitumor Activity in Mice

Tetrazolato-bridged dinuclear platinum(II) complexes ([{cis-Pt(NH₃)₂}₂(μ-OH)(μ-5-R-tetrazolato-N2,N3)]²⁺; tetrazolato-bridged complexes) show remarkable cytotoxic effects in vitro and antitumor activity in vivo. Here, we examined the structure-activity relationship of a series of fluorine-containing derivatives (R = CFH₂, CF₂H, or CF₃), focusing on their lipophilicity, cellular accumulation, cytotoxicity, interactions with a nucleobase and double-stranded deoxyribonucleic acid, and in vivo antitumor efficacy. Fluorination had a little effect on the properties of the derivatives in vitro; however, marked differences in in vitro cytotoxicity and in vivo tumor growth inhibition activity were observed. In BALB/c mice bearing colon-26 tumors, the antitumor efficacies of the derivatives were markedly altered, even by changing the number of fluorine atoms by one. In addition, one derivative, [{cis-Pt(NH₃)₂}₂(μ-OH)(μ-5-difluoromethyltetrazolato-N2,N3)](NO₃)₂, showed a significantly higher antitumor efficacy compared with oxaliplatin, a current first-line drug and the only platinum-based drug approved for the treatment of colon cancer. Together, the present results indicate that introducing fluorine into tetrazolato-bridged complexes may be useful for modulating in vivo activities.

Metal- and metalloid-based compounds to target and reverse cancer multidrug resistance

Drug resistance remains the major cause of cancer treatment failure especially at the late stage of the disease. However, based on their versatile chemistry, metal and metalloid compounds offer the possibility to design fine-tuned drugs to circumvent and even specifically target drug-resistant cancer cells. Based on the paramount importance of platinum drugs in the clinics, two main areas of drug resistance reversal strategies exist: overcoming resistance to platinum drugs as well as multidrug resistance based on ABC efflux pumps. The current review provides an overview of both aspects of drug design and discusses the open questions in the field. The areas of drug resistance covered in this article involve: 1) Altered expression of proteins involved in metal uptake, efflux or intracellular distribution, 2) Enhanced drug efflux via ABC transporters, 3) Altered metabolism in drug-resistant cancer cells, 4) Altered thiol or redox homeostasis, 5) Altered DNA damage recognition and enhanced DNA damage repair, 6) Impaired induction of apoptosis and 7) Altered interaction with the immune system. This review represents the first collection of metal (including platinum, ruthenium, iridium, gold, and copper) and metalloid drugs (e.g. arsenic and selenium) which demonstrated drug resistance reversal activity. A special focus is on compounds characterized by collateral sensitivity of ABC transporter-overexpressing cancer cells. Through this approach, we wish to draw the attention to open research questions in the field. Future investigations are warranted to obtain more insights into the mechanisms of action of the most potent compounds which target specific modalities of drug resistance.

The Effect of a New Glucose-Methotrexate Conjugate on Acute Lymphoblastic Leukemia and Non-Hodgkin's Lymphoma Cell Lines

Patients with hematologic malignancies require intensive therapies, including high-dose chemotherapy. Antimetabolite-methotrexate (MTX) has been used for many years in the treatment of leukemia and in lymphoma patients. However, the lack of MTX specificity causes a significant risk of morbidity, mortality, and severe side effects that impairs the quality of patients' life. Therefore, novel targeted therapies based on the malignant cells' common traits have become an essential treatment strategy. Glucose transporters have been found to be overexpressed in neoplastic cells, including hematologic malignancies. In this study, we biologically evaluated a novel glucose-methotrexate conjugate (Glu-MTX) in comparison to a free MTX. The research aimed to assess the effectiveness of Glu-MTX on chosen human lymphoma and leukemia cell lines. Cell cytotoxicity was verified by MTT viability test and flow cytometry. Moreover, the cell cycle and cellular uptake of Glu-MTX were evaluated. Our study reveals that conjugation of methotrexate with glucose significantly increases drug uptake and results in similar cytotoxicity of the synthesized compound. Although the finding has been confined to in vitro studies, our observations shed light on a potential therapeutic approach that increases the selectivity of chemotherapeutics and can improve leukemia and lymphoma patients' outcomes.

Vitamin C activates pyruvate dehydrogenase (PDH) targeting the mitochondrial tricarboxylic acid (TCA) cycle in hypoxic KRAS mutant colon cancer

Background: In hypoxic tumors, positive feedback between oncogenic KRAS and HIF-1α involves impressive metabolic changes correlating with drug resistance and poor prognosis in colorectal cancer. Up to date, designed KRAS-targeting molecules do not show clear benefits in patient overall survival (POS) so pharmacological modulation of aberrant tricarboxylic acid (TCA) cycle in hypoxic cancer has been proposed as a metabolic vulnerability of KRAS-driven tumors. Methods: Annexin V-FITC and cell viability assays were carried out in order to verify vitamin C citotoxicity in KRAS mutant SW480 and DLD1 as well as in Immortalized Human Colonic Epithelial Cells (HCEC). HIF1a expression and activity were determined by western blot and functional analysis assays. HIF1a direct targets GLUT1 and PDK1 expression was checked using western blot and qRT-PCR. Inmunohistochemical assays were perfomed in tumors derived from murine xenografts in order to validate previous observations in vivo. Vitamin C dependent PDH expression and activity modulation were detected by western blot and colorimetric activity assays. Acetyl-Coa levels and citrate synthase activity were assessed using colorimetric/fluorometric activity assays. Mitochondrial membrane potential (Δψ) and cell ATP levels were assayed using fluorometric and luminescent test. Results: PDK-1 in KRAS mutant CRC cells and murine xenografts was downregulated using pharmacological doses of vitamin C through the proline hydroxylation (Pro402) of the Hypoxia inducible factor-1(HIF-1)α, correlating with decreased expression of the glucose transporter 1 (GLUT-1) in both models. Vitamin C induced remarkable ATP depletion, rapid mitochondrial Δψ dissipation and diminished pyruvate dehydrogenase E1-α phosphorylation at Serine 293, then boosting PDH and citrate synthase activity. Conclusion: We report a striking and previously non reported role of vitamin C in the regulation of the pyruvate dehydrogenase (PDH) activity, then modulating the TCA cycle and mitochondrial metabolism in KRAS mutant colon cancer. Potential impact of vitamin C in the clinical management of anti-EGFR chemoresistant colorectal neoplasias should be further considered.

Glycans Meet Sphingolipids: Structure-Based Design of Glycan Containing Analogues of a Sphingosine Kinase Inhibitor

Sphingosine 1-phosphate (S1P) is a bioactive lipid mediator associated with diverse homeostatic and signaling roles. Enhanced biosynthesis of S1P, mediated by the sphingosine kinase isozymes (SK1 and SK2), is implicated in several pathophysiological conditions and diseases, including skeletal muscle fibrosis, inflammation, multiple sclerosis, and cancer. Therefore, therapeutic approaches that control S1P production have focused on the development of SK1/2 inhibitors. In this framework, we designed a series of natural monosaccharide-based compounds to enhance anchoring of the known SK1 inhibitor PF-543 at the polar head of the J-shaped substrate-binding channel. Herein, we describe the structure-based design and synthesis of new glycan-containing PF-543 analogues and we demonstrate their efficiency in a TGFβ1-induced pro-fibrotic assay.

Diplatin, a novel water-soluble platinum complex, inhibits lung cancer growth via augmentation of Fas-mediated apoptosis

Platinum drugs, such as cisplatin (DDP) and carboplatin (CBP), are the main drugs for the treatment of lung cancer, but their practical clinical application is limited by severe toxicity and acquired drug resistance. Our previous study has indicated that diplatin, [2-(4-(diethyl-amino)butyl)malonate-O,O']-[(1R,2R)-cyclohexane-1,2-diamine N,N'] platinum (II) phosphate, a novel water-soluble platinum complex, could overcome DDP-resistant cells and was less toxic than comparable platinum drugs. In the present study, the effects and mechanisms of diplatin were further evaluated for its development as a novel anti-lung cancer platinum drug. Here, we found diplatin down-regulated the viability of H460 and LTEP-A-2 cells in a dose-dependent manner. Nude mice administrated with diplatin (30-120 mg/kg) via tail vein injection dose-dependently inhibited the growth of H460 and LTEP-A-2 xenograft tumors, whose action mainly correlated with the induction of tumor apoptosis. Particularly, the exposure of lung cancer cells or xenograft tumors to diplatin resulted in elevated Fas level, and knockdown of Fas ameliorated diplatin-induced cells apoptosis. Overall, we suggest that diplatin has potent anti-tumor activity, which probably acts through Fas-mediated signaling pathway.

Targeted tumour theranostics in mice via carbon quantum dots structurally mimicking large amino acids

Strategies for selectively imaging and delivering drugs to tumours typically leverage differentially upregulated surface molecules on cancer cells. Here, we show that intravenously injected carbon quantum dots, functionalized with multiple paired α-carboxyl and amino groups that bind to the large neutral amino acid transporter 1 (which is expressed in most tumours), selectively accumulate in human tumour xenografts in mice and in an orthotopic mouse model of human glioma. The functionalized quantum dots, which structurally mimic large amino acids and can be loaded with aromatic drugs through π–π stacking interactions, enabled—in the absence of detectable toxicity—near-infrared fluorescence and photoacoustic imaging of the tumours and a reduction in tumour burden after the targeted delivery of chemotherapeutics to the tumours. The versatility of functionalization and high tumour selectivity of the quantum dots make them broadly suitable for tumour-specific imaging and drug delivery.

Intravenously injected functionalized carbon quantum dots that bind to the large neutral amino acid transporter 1 and that structurally mimic large amino acids selectively accumulate in human tumours in mice, facilitating targeted theranostics.

Glycoconjugation as a Promising Treatment Strategy for Psoriasis

Despite the progress in the development of novel treatment modalities, a significant portion of patients with psoriasis remains undertreated relative to the severity of their disease. Recent evidence points to targeting the glucose transporter 1 and sugar metabolism as a novel therapeutic strategy for the treatment of psoriasis and other hyperproliferative skin diseases. In this review, we discuss glycoconjugation, an approach that facilitates the pharmacokinetics of cytotoxic molecules and ensures their preferential influx through glucose transporters. We propose pathways of glycoconjugate synthesis to increase effectiveness, cellular selectivity, and tolerability of widely used antipsoriatic drugs. The presented approach exploiting the heightened glucose requirement of proliferating keratinocytes bears the potential to revolutionize the management of psoriasis. SIGNIFICANCE STATEMENT: Recent findings concerning the fundamental role of enhanced glucose metabolism and glucose transporter 1 overexpression in the pathogenesis of psoriasis brought to light approaches that proved successful in cancer treatment. Substantial advances in the emerging field of glycoconjugation highlight the rationale for the development of glucose-conjugated antipsoriatic drugs to increase their effectiveness, cellular selectivity, and tolerability. The presented approach offers a novel therapeutic strategy for the treatment of psoriasis and other hyperproliferative skin diseases.

Sugar ligand-mediated drug delivery

Sugar ligand molecules, such as mannose, galactose and glucose, can bind to drug-delivery systems, making them targeted. These glycosylation ligands have the advantages of nontoxicity, no immunogenicity, good biocompatibility and biodegradation. They can be widely used in glycosylation-modified drug-delivery systems. Herein, the targeting mechanisms, synthesis methods and targeting characteristics of glycosylation-modified drug-delivery systems were reviewed.

TO901317 inhibits the development of hepatocellular carcinoma by LXRα/Glut1 decreasing glycometabolism

This study was conducted to observe the effect and possible mechanism of TO901317 in vivo and in vitro to provide a new basis for the targeted therapy of hepatocellular carcinoma (HCC). The expressions of liver X receptor (LXR)-α, glucose transporter (Glut)-1, proliferating cell nuclear antigen (PCNA), and matrix metalloproteinase (MMP)-9 were analyzed from HCC public database (NCBI PubMed database). The result showed that LXRα was downregulated, whereas Glut1, PCNA, and MMP9 were upregulated in human HCC compared with normal liver. Furthermore, LXRα mRNA was negatively correlated with Glut1 mRNA. At the same time, HCC cells were cultivated in vitro and axillary injected in nude mice to establish the xenograft model. The xenograft in the TO901317-treated group was slower and smaller than the control group. The protein expression of LXRα, Glut1, and MMP9 could be detected by Western blot and glucose level. As a result, TO901317 could inhibit the cell proliferation of HCC in a dose-dependent manner by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. With the increase of TO901317 concentration, the cellular glucose concentration and ATP level were gradually decreased. Western blot results showed TO901317 could upregulate LXRα expression but downregulate MMP9 and Glut1 expression. Transwell and wound-healing analysis confirmed that, by increasing the concentration of TO901317, the cell invasion and migration were both decreased. LXRα small-interfering RNA (siRNA) could relieve the suppression effect of TO901317 on the cell invasion and migration and the expression of LXRα, Glut1, and MMP9. The glucose concentration was also raised. TO901317 could repress the progress of HCC cells by reducing the glucose concentration, upregulating LXRα expression, but downregulating the expression of Glut1 and MMP9. NEW & NOTEWORTHY This subject confirmed that TO901317, a specific liver X receptor agonist, could inhibit the progression of liver cancer through upregulating liver X receptor-α, downregulating the expression of glucose transporter-1 and matrix metalloproteinase-9, and decreasing the glucose content in SMMC-7721 and HepG2 cells.

Toward Multi-Targeted Platinum and Ruthenium Drugs-A New Paradigm in Cancer Drug Treatment Regimens?

While medicinal inorganic chemistry has been practised for over 5000 years, it was not until the late 1800s when Alfred Werner published his ground-breaking research on coordination chemistry that we began to truly understand the nature of the coordination bond and the structures and stereochemistries of metal complexes. We can now readily manipulate and fine-tune their properties. This had led to a multitude of complexes with wide-ranging biomedical applications. This review will focus on the use and potential of metal complexes as important therapeutic agents for the treatment of cancer. With major advances in technologies and a deeper understanding of the human genome, we are now in a strong position to more fully understand carcinogenesis at a molecular level. We can now also rationally design and develop drug molecules that can either selectively enhance or disrupt key biological processes and, in doing so, optimize their therapeutic potential. This has heralded a new era in drug design in which we are moving from a single- toward a multitargeted approach. This approach lies at the very heart of medicinal inorganic chemistry. In this review, we have endeavored to showcase how a "multitargeted" approach to drug design has led to new families of metallodrugs which may not only reduce systemic toxicities associated with modern day chemotherapeutics but also address resistance issues that are plaguing many chemotherapeutic regimens. We have focused our attention on metallodrugs incorporating platinum and ruthenium ions given that complexes containing these metal ions are already in clinical use or have advanced to clinical trials as anticancer agents. The "multitargeted" complexes described herein not only target DNA but also contain either vectors to enable them to target cancer cells selectively and/or moieties that target enzymes, peptides, and intracellular proteins. Multitargeted complexes which have been designed to target the mitochondria or complexes inspired by natural product activity are also described. A summary of advances in this field over the past decade or so will be provided.

Smart Magnetic Nanoaptamer: Construction, Subcellular Distribution, and Silencing HIF for Cancer Gene Therapy

Attenuating the expression of HIF-1α (hypoxic inducible factor) by siRNA has an effect on the proliferation of hypoxia cancers. Mitochondria targeting siRNA may silence the level of HIF-1α for cancer gene therapy. A GAG-rich DNA was conjugated to GC-rich DNA for the synthesis of functional magnetic nanoaptamer (DNA-Fe₃O₄) to keep the innate character of the targeting aptamer. The DNA-Fe₃O₄ can load the hydrophobic dye (BODIPY-OCH₃) by the GC-rich sequences, resulting in fluorescent nanoaptamer (BFe@DNA). Self-assembly of BFe@DNA with target aptamer resulted in the formation of BFe@DNA_H. Subcellular fluorescence imaging results confirm that BFe@DNA_H can accumulate in MCF-7 cells and selectively target mitochondrion. In particular, BFe@DNA_H can transport siRNA to breast cancer cells or tissues for the attenuation of HIF-1α and ATP and the inhibition on growth of cancer cells in vivo. Therefore, BFe@DNA_H is a smart nanoaptamer platform for the development of subcellular imaging agents and gene therapy.