Magnetic nanocarriers for the specific delivery of siRNA: Contribution of breast cancer cells active targeting for down-regulation efficiency

Precision arrows: Navigating breast cancer with nanotechnology siRNA

Nanotechnology-based drug delivery systems, including siRNA, present an innovative approach to treating breast cancer, which disproportionately affects women. These systems enable personalized and targeted therapies, adept at managing drug resistance and minimizing off-target effects. This review delves into the current landscape of nanotechnology-derived siRNA transport systems for breast cancer treatment, discussing their mechanisms of action, preclinical and clinical research, therapeutic applications, challenges, and future prospects. Emphasis is placed on the importance of targeted delivery and precise gene silencing in improving therapeutic efficacy and patient outcomes. The review addresses specific hurdles such as specificity, biodistribution, immunological reactions, and regulatory approval, offering potential solutions and avenues for future research. SiRNA drug delivery systems hold promise in revolutionizing cancer care and improving patient outcomes, but realizing their full potential necessitates ongoing research, innovation, and collaboration. Understanding the intricacies of siRNA delivery mechanisms is pivotal for designing effective cancer treatments, overcoming challenges, and advancing siRNA-based therapies for various diseases, including cancer. The article provides a comprehensive review of the methods involved in siRNA transport for therapeutic applications, particularly in cancer treatment, elucidating the complex journey of siRNA molecules from extracellular space to intracellular targets. Key mechanisms such as endocytosis, receptor-mediated uptake, and membrane fusion are explored, alongside innovative delivery vehicles and technologies that enhance siRNA delivery efficiency. Moreover, the article discusses challenges and opportunities in the field, including issues related to specificity, biodistribution, immune response, and clinical translation. By comprehending the mechanisms of siRNA delivery, researchers can design and develop more effective siRNA-based therapies for various diseases, including cancer.

Inorganic nanocarriers for siRNA delivery for cancer treatments

RNA interference is one of the emerging methodologies utilized in the treatment of a wide variety of diseases including cancer. This method specifically uses therapeutic RNAs (TpRNAs) like small interfering RNAs (siRNAs) to regulate/silence the cancer-linked genes, thereby minimizing the distinct activities of the cancer cells while aiding in their apoptosis. But, many complications arise during the transport/delivery of these TpRNAs that include poor systemic circulation, instability/degradation inside the body environment, no targeting capacity and also low cellular internalization. These difficulties can be overcome by using nanocarriers to deliver the TpRNAs inside the cancer cells. The following are the various categories of nanocarriers-viral vectors (e.g. lentivirus and adenovirus) and non-viral nanocarriers (self-assembling nanocarriers and inorganic nanocarriers). Viral vectors suffer from disadvantages like high immunogenicity compared to the non-viral nanocarriers. Among non-viral nanocarriers, inorganic nanocarriers gained significant attention as their inherent properties (like magnetic properties) can aid in the effective cellular delivery of the TpRNAs. Most of the prior reports have discussed about the delivery of TpRNAs through self-assembling nanocarriers; however very few have reviewed about their delivery using the inorganic nanoparticles. Therefore, in this review, we have mainly focussed on the delivery of TpRNAs-i.e. siRNA, especially programmed death ligand-1 (PD-L1), survivin, B-cell lymphoma-2 (Bcl-2), vascular endothelial growth factor and other siRNAs using the inorganic nanoparticles-mainly magnetic, metal and silica nanoparticles. Moreover, we have also discussed about the combined delivery of these TpRNAs along with chemotherapeutic drugs (mainly doxorubicin) andin vitroandin vivotherapeutic effectiveness.

Recent advances in magnetic nanocarriers for tumor treatment

Magnetic nanocarriers are nano-platforms that integrate multiple moieties based on magnetic nanoparticles for diagnostic and therapeutic purposes. In recent years, they have become an advanced platform for tumor treatment due to their wide application in magnetic resonance imaging (MRI), biocatalysis, magneto-thermal therapy (MHT), and photoresponsive therapy. Drugs loaded into magnetic nanocarriers can efficiently be directed to targeted areas by precisely reshaping their structural properties. Magnetic nanocarriers allow us to track the location of the therapeutic agent, continuously control the therapeutic process and eventually assess the efficacy of the treatment. They are typically used in synergistic therapeutic applications to achieve precise and effective tumor treatment. Here we review their latest applications in tumor treatment, including stimuli-responsive drug delivery, MHT, photoresponsive therapy, immunotherapy, gene therapy, and synergistic therapy. We consider reducing toxicity, improving antitumor efficacy, and the targeting accuracy of magnetic nanocarriers. The challenges of their clinical translation and prospects in cancer therapy are also discussed.

siRNA and targeted delivery systems in breast cancer therapy

Recently, nucleic acid drugs have been considered as promising candidates in treatment of various diseases, especially cancer. Because of developing resistance to conventional chemotherapy, use of genetic tools in cancer therapy appears inevitable. siRNA is a RNAi tool with capacity of suppressing target gene. Owing to overexpression of oncogenic factors in cancer, siRNA can be used for suppressing those pathways. This review emphasizes the function of siRNA in treatment of breast tumor. The anti-apoptotic-related genes including Bcl-2, Bcl-xL and survivin can be down-regulated by siRNA in triggering cell death in breast cancer. STAT3, STAT8, Notch1, E2F3 and NF-κB are among the factors with overexpression in breast cancer that their silencing by siRNA paves the way for impairing tumor proliferation and invasion. The oncogenic mechanisms in drug resistance development in breast tumor such as lncRNAs can be suppressed by siRNA. Furthermore, siRNA reducing P-gp activity can increase drug internalization in tumor cells. Because of siRNA degradation at bloodstream and low accumulation at tumor site, nanoplatforms have been employed for siRNA delivery to suppress breast tumor progression via improving siRNA efficacy in gene silencing. Development of biocompatible and efficient nanostructures for siRNA delivery can make milestone progress in alleviation of breast cancer patients.

Combination of Nanovectorized siRNA Directed against Survivin with Doxorubicin for Efficient Anti-Cancer Activity in HER2+ Breast Cancer Cells

According to Globocan 2020, breast cancer is considered one of the most common cancers affecting women and is one of the leading causes of death in over 100 countries. The available classical treatment options do not always give satisfactory outcomes, and some patients develop resistance to these treatments. This study aims to investigate the combination of nanovectorized siRNA directed against anti-apoptotic protein Survivin (siSurvivin) by targeted stealth magnetic siRNA nanovectors (TS-MSN), designed in our lab, with Doxorubicin (DOX), as an option for HER2+ breast cancer treatment. The hypothesis is that the pretreatment of the HER2+ breast cancer cell line SK-BR-3 with siSurvivin will induce apoptosis in the cancer cells and enhance the therapeutic efficacy of DOX, allowing a dose reduction of DOX and hence a reduction of potential side effects. TS-MSN are based on superparamagnetic iron oxide nanoparticles (SPIONs) covalently coupled with a fluorophore sulfocyanine-5 and polyethylene glycol 5000 (PEG₅₀₀₀) and functionalized with single-chain variable fragments (scFv) of an antibody targeting the HER2 membrane receptor. These covalently functionalized SPIONs are then complexed via electrostatic interactions with therapeutic siRNA and the cationic polymers, chitosan, and poly-L-arginine. TS-MSN_siSurvivin had an average size of 144 ± 30 nm, a PDI of 0.3, and a slightly positive zeta potential value of 10.56 ± 05.70 mV. The agarose gel electrophoresis assay confirmed that the siRNA is well-complexed into TS-MSN without leakage, as no free siRNA was detected. Moreover, siRNA in TS-MSN was protected from RNAse A degradation for up to 6 h at 37 °C. Formulations of TS-MSN with siSurvivin demonstrated in vitro gene knockdown up to 89% in the HER2+ breast cancer cell line SK-BR-3. Furthermore, qRT-PCR confirmed a significant Survivin mRNA relative expression inhibition (about 50%) compared to control siRNA or untreated cells. A combination protocol was evaluated between TS-MSN and Doxorubicin (DOX) for the first time. Therefore, SK-BR-3 cells were pretreated with TS-MSN formulated with siSurvivin at 50 nM for 24 h alone, before a DOX treatment at a concentration of 0.5 µM (corresponding to the IC₅₀) was added for 48 h. The MTT cytotoxicity tests, performed after 72 h of treatment, revealed that the combination had a significant synergistic cytotoxic effect on SK-BR-3 cells compared to monotherapies or untreated cells. We confirmed that pretreatment of cells with siSurvivin potentializes the cytotoxic effect of DOX as an alternative approach for treating HER2+ breast cancer. In conclusion, a combination of anti-Survivin siRNA and DOX would be a good alternative in HER2+ breast cancer therapy.

Aptamer-siRNA chimeras: Promising tools for targeting HER2 signaling in cancer

RNA interference is a transformative approach and has great potential in the development of novel and more efficient cancer therapeutics. Immense prospects exist in the silencing of HER2 and its downstream genes which are overexpressed in many cancers, through exogenously delivered siRNA. However, there is still a long way to exploit the full potential and versatility of siRNA therapeutics due to the challenges associated with the stability and delivery of siRNA targeted to specific sites. Aptamers offer several advantages as a vehicle for siRNA delivery, over other carriers such as antibodies. In this review, we discuss the progress made in the development and applications of aptamer-siRNA chimeras in HER2 targeting and gene silencing. A schematic workflow is also provided which will provide ample insight for all those researchers who are new to this field. Also, we think that a mechanistic understanding of the HER2 signaling pathway is crucial in designing extensive investigations aimed at the silencing of a wider array of genes. This review is expected to stimulate more research on aptamer-siRNA chimeras targeted against HER2 which might arm us with potential effective therapeutic interventions for the management of cancer.

Trends in iron oxide nanoparticles: a nano-platform for theranostic application in breast cancer

Breast cancer (BC) is the deadliest malignant disorder globally, with a significant mortality rate. The development of tolerance throughout cancer treatment and non-specific targeting limits the drug's response. Currently, nano therapy provides an interdisciplinary area for imaging, diagnosis, and targeted drug delivery for BC. Several overexpressed biomarkers, proteins, and receptors are identified in BC, which can be potentially targeted by using nanomaterial for drug/gene/immune/photo-responsive therapy and bio-imaging. In recent applications, magnetic iron oxide nanoparticles (IONs) have shown tremendous attention to the researcher because they combine selective drug delivery and imaging functionalities. IONs can be efficaciously functionalised for potential application in BC therapy and diagnosis. In this review, we explored the current application of IONs in chemotherapeutics delivery, gene delivery, immunotherapy, photo-responsive therapy, and bio-imaging for BC based on their molecular mechanism. In addition, we also highlighted the effect of IONs' size, shape, dimension, and functionalization on BC targeting and imaging. To better comprehend the functionalization potential of IONs, this paper provides an outline of BC cellular development. IONs for BC theranostic are also reviewed based on their clinical significance and future aspects.

Peptides to Overcome the Limitations of Current Anticancer and Antimicrobial Nanotherapies

Biomedical research devotes a huge effort to the development of efficient non-viral nanovectors (NV) to improve the effectiveness of standard therapies. NVs should be stable, sustainable and biocompatible and enable controlled and targeted delivery of drugs. With the aim to foster the advancements of such devices, this review reports some recent results applicable to treat two types of pathologies, cancer and microbial infections, aiming to provide guidance in the overall design of personalized nanomedicines and highlight the key role played by peptides in this field. Additionally, future challenges and potential perspectives are illustrated, in the hope of accelerating the translational advances of nanomedicine.

Advances in nanotechnology-based platforms for survivin-targeted drug discovery

INTRODUCTION

Due to its unique functional impact on multiple cancer cell circuits including proliferation, apoptosis, tumor dissemination, DNA damage repair and immune response, the inhibitor of apoptosis protein (IAP) survivin has gained high interest as a molecular target and a multitude of therapeutics were developed to interfere with survivin expression and functionality. First clinical evaluations of these therapeutics, however, were disappointing highlighting the need to develop advanced delivery systems of survivin-targeting molecules to increase stability, bioavailability as well as the selective guidance to tumor tissue.

AREAS COVERED

: This review focuses on advancements in nanocarriers to molecularly target survivin in human malignancies. A plethora of nanoparticle platforms, including liposomes, polymeric systems, dendrimers, inorganic nanocarriers, RNA/DNA nanotechnology and exosomes are discussed in the background of survivin-tailored RNA interference, small molecule inhibitors, dominant negative mutants or survivin vaccination or combined modality treatment with chemotherapeutic drugs and photo- dynamic/photothermal strategies.

EXPERT OPINION

Novel therapeutic approaches include the use of biocompatible nanoformulations carrying gene silencing or drug molecules to directly or indirectly target proteins, allow for a more precise and controlled delivery of survivin therapeutics. Moreover, surface modification of these nanocarriers may result in a tumor entity specific delivery. Therefore, nanomedicine exploiting survivin-tailored strategies in a multimodal background is considered the way forwaerd to enhance the development of future personalized medicine.

An effective polymeric nanocarrier that allows for active targeting and selective drug delivery in cell coculture systems

In this manuscript, we report the development of a versatile, robust, and stable targeting nanocarrier for active delivery. This nanocarrier is based on bifunctionalized polymeric nanoparticles conjugated to a monoclonal antibody that allows for active targeting of either (i) a fluorophore for tracking or (ii) a drug for monitoring specific cell responses. This nanodevice can efficiently discriminate between cells in coculture based on the expression levels of cell surface receptors. As a proof of concept, we have demonstrated efficient delivery using a broadly established cell surface receptor as the target, the epidermal growth factor receptor (EGFR), which is overexpressed in several types of cancers. Additionally, a second validation of this nanodevice was successfully carried out using another cell surface receptor as the target, the cluster of differentiation 147 (CD147). Our results suggest that this versatile nanocarrier can be expanded to other cell receptors and bioactive cargoes, offering remarkable discrimination efficiency between cells with different expression levels of a specific marker. This work supports the ability of nanoplatforms to boost and improve the progress towards personalized medicine.

Chitosan based-nanoparticles and nanocapsules: Overview, physicochemical features, applications of a nanofibrous scaffold, and bioprinting

Recent advancements in the synthesis, properties, and applications of chitosan as the second after cellulose available biopolymer in nature were discussed in this review. A general overview of processing and production procedures from A to Z was highlighted. Chitosan exists in three polymorphic forms which differ in degree of crystallinity (α, β, and γ). Thus, the degree of deacetylation, crystallinity, surface area, and molecular mass significantly affect most applications. Otherwise, the synthesis of chitosan nanofibers is suffering from many drawbacks that were recently treated by co-electrospun with other polymers such as polyvinyl alcohol (PVA), polyethylene oxide (PEO), and polycaprolactone (PCL). Ultimately, this review focuses on the area of new trend utilization of chitosan nanoparticles as nanospheres and nanocapsules, in cartilage and bone regenerative medicine. Owing to its biocompatibility, bioavailability, biodegradability, and costless synthesis, chitosan is a promising biopolymeric structure for water remediation, drug delivery, antimicrobials, and tissue engineering.

Critical role of HOX transcript antisense intergenic RNA (HOTAIR) in gliomas

Despite extensive research, gliomas are associated with high morbidity and mortality, mainly attributed to the rapid growth rate, excessive invasiveness, and molecular heterogeneity, as well as regenerative potential of cancer stem cells. Therefore, elucidation of the underlying molecular mechanisms and the identification of potential molecular diagnostic and prognostic biomarkers are of paramount importance. HOX transcript antisense intergenic RNA (HOTAIR) is a well-studied long noncoding RNA, playing an emerging role in tumorigenesis of several human cancers. A growing amount of preclinical and clinical evidence highlights the pro-oncogenic role of HOTAIR in gliomas, mainly attributed to the enhancement of proliferation and migration, as well as inhibition of apoptosis. In vitro and in vivo studies demonstrate that HOTAIR modulates the activity of specific transcription factors, such as MXI1, E2F1, ATF5, and ASCL1, and regulates the expression of cell cycle-associated genes along with related signaling pathways, like the Wnt/β-catenin axis. Moreover, it can interact with specific miRNAs, including miR-326, miR-141, miR-148b-3p, miR-15b, and miR-126-5p. Of importance, HOTAIR has been demonstrated to enhance angiogenesis and affect the permeability of the blood-tumor barrier, thus modulating the efficacy of chemotherapeutic agents. Herein, we provide evidence on the functional role of HOTAIR in gliomas and discuss the benefits of its targeting as a novel approach toward glioma treatment.

HER-2/neu and MYC gene silencing in breast cancer: therapeutic potential and advancement in nonviral nanocarrier systems

Globally, breast cancer is the second leading cause of cancer-related mortality among women, with approximately 1.4 million new cases diagnosed annually. Associated genetic perturbations are emerging in the face of intense scientific enquiry, facilitating its classification, prognostication and treatment. RNAi, utilizing siRNA, is a powerful treatment strategy to silence disease-causing genes. However, therapeutic siRNA instability and poor cellular uptake have limited its clinical application, necessitating the use of nanocarriers. In this review, we highlight the RNAi mechanism, HER-2/neu and MYC as breast cancer gene targets, and nonviral nanocarriers as potentially safe and efficient delivery systems.

Cyclo-RGD Truncated Polymeric Nanoconstruct with Dendrimeric Templates for Targeted HDAC4 Gene Silencing in a Diabetic Nephropathy Mouse Model

Diabetic nephropathy (DN), a chronic progressive kidney disease, is a significant complication of diabetes mellitus. Dysregulation of the histone deacetylases (HDACs) gene has been implicated in the pathogenesis of DN. Hence, the HDAC-inhibitors have emerged as a critical class of therapeutic agents in DN; however, the currently available HDAC4-inhibitors are mostly nonselective in nature as well as inhibit multiple HDACs. RNA interference of HDAC4 (HDAC4 siRNA) has shown immense promise, but the clinical translation has been impeded due to lack of a targeted, specific, and in vivo applicable delivery modality. In the present investigation, we examined Cyclo(RGDfC) (cRGD) truncated polymeric nanoplex with dendrimeric templates for targeted HDAC4 Gene Silencing. The developed nanoplex exhibited enhanced encapsulation of siRNA and offered superior protection against serum RNase nucleases degradation. The nanoplex was tested on podocytes (in vitro), wherein it showed selective binding to the αvβ3 integrin receptor, active cellular uptake, and significant in vitro gene silencing. The in vivo experiments showed remarkable suppression of the HDAC4 and inhibition in the progression of renal fibrosis in the Streptozotocin (STZ) induced DN C57BL/6 mice model. Histopathological and toxicological studies revealed nonsignificant abnormality/toxicity with the nanoplex. Conclusively, nanoplex was found as a promising tactic for targeted therapy of podocytes and could be extended for other kidney-related ailments.

Synthesis, Principles, and Properties of Magnetite Nanoparticles for In Vivo Imaging Applications-A Review

The current nanotechnology era is marked by the emergence of various magnetic inorganic nanometer-sized colloidal particles. These have been extensively applied and hold an immense potential in biomedical applications including, for example, cancer therapy, drug nanocarriers (NCs), or in targeted delivery systems and diagnosis involving two guided-nanoparticles (NPs) as nanoprobes and contrast agents. Considerable efforts have been devoted to designing iron oxide NPs (IONPs) due to their superparamagnetic (SPM) behavior (SPM IONPs or SPIONs) and their large surface-to-volume area allowing more biocompatibility, stealth, and easy bonding to natural biomolecules thanks to grafted ligands, selective-site moieties, and/or organic and inorganic corona shells. Such nanomagnets with adjustable architecture have been the topic of significant progresses since modular designs enable SPIONs to carry out several functions simultaneously such as local drug delivery with real-time monitoring and imaging of the targeted area. Syntheses of SPIONs and adjustments of their physical and chemical properties have been achieved and paved novel routes for a safe use of those tailored magnetic ferrous nanomaterials. Herein we will emphasis a basic notion about NPs magnetism in order to have a better understanding of SPION assets for biomedical applications, then we mainly focus on magnetite iron oxide owing to its outstanding magnetic properties. The general methods of preparation and typical characteristics of magnetite are reviewed, as well as the major biomedical applications of magnetite.