Epidermal growth factor receptor aptamer-conjugated polymer-lipid hybrid nanoparticles enhance salinomycin delivery to osteosarcoma and cancer stem cells

Surface Functionalized Lipid Nanoparticles in Promoting Therapeutic Outcomes: An Insight View of the Dynamic Drug Delivery System

Compared to the conventional approach, nanoparticles (NPs) facilitate a non-hazardous, non-toxic, non-interactive, and biocompatible system, rendering them incredibly promising for improving drug delivery to target cells. When that comes to accomplishing specific therapeutic agents like drugs, peptides, nucleotides, etc., lipidic nanoparticulate systems have emerged as even more robust. They have asserted impressive ability in bypassing physiological and cellular barriers, evading lysosomal capture and the proton sponge effect, optimizing bioavailability, and compliance, lowering doses, and boosting therapeutic efficacy. However, the lack of selectivity at the cellular level hinders its ability to accomplish its potential to the fullest. The inclusion of surface functionalization to the lipidic NPs might certainly assist them in adapting to the basic biological demands of a specific pathological condition. Several ligands, including peptides, enzymes, polymers, saccharides, antibodies, etc., can be functionalized onto the surface of lipidic NPs to achieve cellular selectivity and avoid bioactivity challenges. This review provides a comprehensive outline for functionalizing lipid-based NPs systems in prominence over target selectivity. Emphasis has been put upon the strategies for reinforcing the therapeutic performance of lipidic nano carriers' using a variety of ligands alongside instances of relevant commercial formulations.

Ligand-based active targeting strategies for cancer theranostics

In the past decades, for the intermediate or advanced cancerous stages, preclinical and clinical applications of nanomedicines in cancer theranostics have been extensively studied. Nevertheless, decreased specificity and poor targeting efficiency with low target concentration of theranostic are the major drawbacks of nanomedicine in employing clinical substitution over conventional systemic therapy. Consequently, ligand decorated nanocarrier-mediated targeted drug delivery system can transcend the obstructions through their enhanced retention activity and increased permeability with effective targeting. The highly efficient and specific nanocarrier-mediated ligand-based active therapy is one of the novel and promising approaches for delivery of the therapeutics for different cancers in recent years to restrict various cancer growth in vivo without harming healthy cells. The article encapsulates the features of nanocarrier-mediated ligands in augmentation of active targeting approaches of various cancers and summarizes ligand-based targeted delivery systems in treatment of cancer as plausible theranostics.

Active targeting schemes for nano-drug delivery systems in osteosarcoma therapeutics

Osteosarcoma, the most common malignant tumor of the bone, seriously influences people's lives and increases their economic burden. Conventional chemotherapy drugs achieve limited therapeutic effects owing to poor targeting and severe systemic toxicity. Nanocarrier-based drug delivery systems can significantly enhance the utilization efficiency of chemotherapeutic drugs through targeting ligand modifications and reduce the occurrence of systemic adverse effects. A variety of ligand-modified nano-drug delivery systems have been developed for different targeting schemes. Here we review the biological characteristics and the main challenges of current drug therapy of OS, and further elaborate on different targeting schemes and ligand selection for nano-drug delivery systems of osteosarcoma, which may provide new horizons for the development of advanced targeted drug delivery systems in the future.

Preparation, In Vitro Characterization, and Cytotoxicity Evaluation of Polymeric pH-Responsive Hydrogels for Controlled Drug Release

The aim of the current investigation was based on the development of pH-responsive hydrogels of chondroitin sulfate, carbopol, and polyvinyl alcohol polymerized with acrylic acid in the presence of ammonium persulfate and ethylene glycol dimethylacrylate for controlled drug delivery. A free radical polymerization technique was used for the preparation of these pH-responsive hydrogels. The gel fraction of the prepared hydrogels was increased with the increase in the chondroitin sulfate, carbopol, polyvinyl alcohol, and acrylic acid content, while the sol-fraction was decreased. Swelling and drug release studies were performed in various pH conditions. Greater swelling and drug release were observed at high pH values (pH 4.6 and 7.4) as compared to low pH value (pH 1.2), representing the pH-responsive nature of the synthesized hydrogels. Porosity and drug loading were increased with the incorporation of high concentrations of hydrogel contents except polyvinyl alcohol, which showed reverse effects. Similarly, biodegradation study reported a slow degradation rate of the prepared hydrogels with the increase in hydrogel constituents. Cytotoxicity study proved the safe use of developed hydrogels as no toxic effect was shown on T84 human colon cancer cells. Similarly, various characterizations, including Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy, were performed for prepared hydrogels. Hence, we could demonstrate that the prepared hydrogels can be used as a promising drug carrier for the controlled delivery of drugs.

Depletion of Fibroblast Growth Factor 12 Restrains the Viability, Stemness, and Motility of Colorectal Cancer

Background

Colorectal cancer (CRC) is a leading cause of cancer-related death. CRC patients have a poor prognosis due to tumor metastasis and recurrence. Fibroblast growth factor 12 (FGF12), a member of the FGF family, is highly expressed in several cancers. However, little is known about the roles of FGF12 in CRC progression.

Methods

The overall survival (OS) of CRC patients was detected via Kaplan-Meier analysis. The FGF12 expression in both CRC tissues and cells was analyzed by qRT-PCR, immunohistochemistry (IHC), and western blotting (WB). LoVo and SW480 cells were transfected with shFGF12 lentivirus to silence FGF12. In vivo and in vitro experiments were performed to explore the FGF12 functions in CRC, including CCK-8, Edu, flow cytometry, Transwell, EMT, cancer stemness, and tumor xenograft experiments.

Results

FGF12 was upregulated in both CRC cells and tissues. High expression of FGF12 indicated a shorter OS in CRC patients. FGF12 knockdown inhibited the proliferation, invasion, stemness, and EMT of CRC cells. FGF12 knockdown promoted CRC cell apoptosis in vitro. 740 Y-P (a PI3K/AKT pathway activator) restored the proliferation, stemness, invasion, and EMT in FGF12-deficient cells and reversed LoVo cell apoptosis induced by FGF12 depletion. Depletion of FGF12 inhibited tumor growth, EMT, cancer stemness, and PI3K/AKT pathway in a xenograft mouse model.

Conclusions

FGF12 predicts bad clinical outcome and modulates the viability, stemness, and motility of CRC cells. Our study may provide a new insight for the diagnosis and treatment of CRC.

Targeted Delivery of Chemotherapeutic Agents for Osteosarcoma Treatment

Since osteosarcoma (OS) is an aggressive bone cancer with unknown molecular pathways of etiology and pathophysiology, improving patient survival has long been a challenge. The conventional therapy is a complex multidisciplinary management that include radiotherapy, chemotherapy which followed by surgery and then post-operative adjuvant chemotherapy. However, they have severe side effects because the majority of the medicines used have just a minor selectivity for malignant tissue. As a result, treating tumor cells specifically without damaging healthy tissue is currently a primary goal in OS therapy. The coupling of chemotherapeutic drugs with targeting ligands is a unique therapy method for OS that, by active targeting, can overcome the aforementioned hurdles. This review focuses on advances in ligands and chemotherapeutic agents employed in targeted delivery to improve the capacity of active targeting and provide some insight into future therapeutic research for OS.

Salinomycin-Based Drug Delivery Systems: Overcoming the Hurdles in Cancer Therapy

Cancer stem cells (CSCs) are reportedly responsible for the initiation and propagation of cancer. Since CSCs are highly resistant to conventional chemo- and radiotherapy, they are considered the main cause of cancer relapse and metastasis. Salinomycin (Sali), an anticoccidial polyether antibiotic, has emerged as a promising new candidate for cancer therapy, with selective cytotoxicity against CSCs in various malignancies. Nanotechnology provides an efficient means of delivering Sali to tumors in view of reducing collateral damage to healthy tissues and enhancing the therapeutic outcome. This review offers an insight into the most recent advances in cancer therapy using Sali-based nanocarriers.

Recent Advances in Nanotechnology-Based Diagnosis and Treatments of Human Osteosarcoma

Osteosarcoma (OSA) is a type of bone cancer that begins in the cells that form bones.OSA is a rare mesenchymal bone neoplasm derived from mesenchymal stem cells. Genome disorganization, chromosomal modifications, deregulation of tumor suppressor genes, and DNA repair defects are the factors most responsible for OSA development. Despite significant advances in the diagnosing and treatment of OSA, patients' overall survival has not improved within the last twenty years. Lately, advances in modern nanotechnology have spurred development in OSA management and offered several advantages to overcome the drawbacks of conventional therapies. This technology has allowed the practical design of nanoscale devices combined with numerous functional molecules, including tumor-specific ligands, antibodies, anti-cancer drugs, and imaging probes. Thanks to their small sizes, desirable drug encapsulation efficiency, and good bioavailability, functionalized nanomaterials have found wide-spread applications for combating OSA progression. This review invokes the possible utility of engineered nanomaterials in OSA diagnosis and treatment, motivating the researchers to seek new strategies for tackling the challenges associated with it.

Aptamer-Functionalized Nanoparticles in Targeted Delivery and Cancer Therapy

Using nanoparticles to carry and delivery anticancer drugs holds much promise in cancer therapy, but nanoparticles per se are lacking specificity. Active targeting, that is, using specific ligands to functionalize nanoparticles, is attracting much attention in recent years. Aptamers, with their several favorable features like high specificity and affinity, small size, very low immunogenicity, relatively low cost for production, and easiness to store, are one of the best candidates for the specific ligands of nanoparticle functionalization. This review discusses the benefits and challenges of using aptamers to functionalize nanoparticles for active targeting and especially presents nearly all of the published works that address the topic of using aptamers to functionalize nanoparticles for targeted drug delivery and cancer therapy.

Utilization of Polymer-Lipid Hybrid Nanoparticles for Targeted Anti-Cancer Therapy

Cancer represents one of the most dangerous diseases, with 1.8 million deaths worldwide. Despite remarkable advances in conventional therapies, these treatments are not effective to completely eradicate cancer. Nanotechnology offers potential cancer treatment based on formulations of several nanoparticles (NPs). Liposomes and polymeric nanoparticle are the most investigated and effective drug delivery systems (DDS) for cancer treatment. Liposomes represent potential DDS due to their distinct properties, including high-drug entrapment efficacy, biocompatibility, low cost, and scalability. However, their use is restricted by susceptibility to lipid peroxidation, instability, burst release of drugs, and the limited surface modification. Similarly, polymeric nanoparticles show several chemical modifications with polymers, good stability, and controlled release, but their drawbacks for biological applications include limited drug loading, polymer toxicity, and difficulties in scaling up. Therefore, polymeric nanoparticles and liposomes are combined to form polymer-lipid hybrid nanoparticles (PLHNPs), with the positive attributes of both components such as high biocompatibility and stability, improved drug payload, controlled drug release, longer circulation time, and superior in vivo efficacy. In this review, we have focused on the prominent strategies used to develop tumor targeting PLHNPs and discuss their advantages and unique properties contributing to an ideal DDS.

Aptamers as Versatile Ligands for Biomedical and Pharmaceutical Applications

Aptamers are a class of targeting ligands that bind exclusively to biomarkers of interest. Aptamers have been identified as candidates for the construction of various smart systems for therapy, diagnosis, bioimaging, and drug delivery due to their high target affinity and specificity. Aptamers are accounted as chemical antibodies that can be readily linked to drugs, sensors, signal enhancers, or nanocarriers for functionalization. Use of aptamer-guided medications, especially nanomedicines, has resulted in encouraging outcomes compared to those use of aptamer-free counterparts. This article reviews recent advances in the use of aptamers as targeting ligands for various biomedical and pharmaceutical purposes. Special interests focus on aptamer-based theranostics, biosensing, bioimaging, drug potentiation, and targeted drug delivery.

Recent advances of drug delivery nanocarriers in osteosarcoma treatment

Osteosarcoma is the most common primary malignant bone tumor mainly occurred in children and adolescence, and chemotherapy is limited for the side effects and development of drug resistance. Advances in nanotechnology and knowledge of cancer biology have led to significant improvements in developing tumor-targeted drug delivery nanocarriers, and some have even entered clinically application. Delivery of chemotherapeutic agents by functionalized smart nanocarriers could protect the drugs from rapid clearance, prolong the circulating time, and increase the drug concentration at tumor sites, thus enhancing the therapeutic efficacy and reducing side effects. Various drug delivery nanocarriers have been designed and tested for osteosarcoma treatment, but most of them are still at experimental stage, and more further studies are needed before clinical application. In this present review, we briefly describe the types of commonly used nanocarriers in osteosarcoma treatment, and discuss the strategies for osteosarcoma-targeted delivery and controlled release of drugs. The application of nanoparticles in the management of metastatic osteosarcoma is also briefly discussed. The purpose of this article is to present an overview of recent progress of nanoscale drug delivery platforms in osteosarcoma, and inspire new ideas to develop more effective therapeutic options.

Aptamers Chemistry: Chemical Modifications and Conjugation Strategies

Soon after they were first described in 1990, aptamers were largely recognized as a new class of biological ligands that can rival antibodies in various analytical, diagnostic, and therapeutic applications. Aptamers are short single-stranded RNA or DNA oligonucleotides capable of folding into complex 3D structures, enabling them to bind to a large variety of targets ranging from small ions to an entire organism. Their high binding specificity and affinity make them comparable to antibodies, but they are superior regarding a longer shelf life, simple production and chemical modification, in addition to low toxicity and immunogenicity. In the past three decades, aptamers have been used in a plethora of therapeutics and drug delivery systems that involve innovative delivery mechanisms and carrying various types of drug cargos. However, the successful translation of aptamer research from bench to bedside has been challenged by several limitations that slow down the realization of promising aptamer applications as therapeutics at the clinical level. The main limitations include the susceptibility to degradation by nucleases, fast renal clearance, low thermal stability, and the limited functional group diversity. The solution to overcome such limitations lies in the chemistry of aptamers. The current review will focus on the recent arts of aptamer chemistry that have been evolved to refine the pharmacological properties of aptamers. Moreover, this review will analyze the advantages and disadvantages of such chemical modifications and how they impact the pharmacological properties of aptamers. Finally, this review will summarize the conjugation strategies of aptamers to nanocarriers for developing targeted drug delivery systems.

Ionophores: Potential Use as Anticancer Drugs and Chemosensitizers

Ion homeostasis is extremely important for the survival of both normal as well as neoplastic cells. The altered ion homeostasis found in cancer cells prompted the investigation of several ionophores as potential anticancer agents. Few ionophores, such as Salinomycin, Nigericin and Obatoclax, have demonstrated potent anticancer activities against cancer stem-like cells that are considered highly resistant to chemotherapy and responsible for tumor relapse. The preclinical success of these compounds in in vitro and in vivo models have not been translated into clinical trials. At present, phase I/II clinical trials demonstrated limited benefit of Obatoclax alone or in combination with other anticancer drugs. However, future development in targeted drug delivery may be useful to improve the efficacy of these compounds. Alternatively, these compounds may be used as leading molecules for the development of less toxic derivatives.