In situ forming implants for local chemotherapy and hyperthermia of bone tumors

Nanostructures in Orthopedics: Advancing Diagnostics, Targeted Therapies, and Tissue Regeneration

Nanotechnology, delving into the realm of nanometric structures, stands as a transformative force in orthopedics, reshaping diagnostics, and numerous regenerative interventions. Commencing with diagnostics, this scientific discipline empowers accurate analyses of various diseases and implant stability, heralding an era of unparalleled precision. Acting as carriers for medications, nanomaterials introduce novel therapeutic possibilities, propelling the field towards more targeted and effective treatments. In arthroplasty, nanostructural modifications to implant surfaces not only enhance mechanical properties but also promote superior osteointegration and durability. Simultaneously, nanotechnology propels tissue regeneration, with nanostructured dressings emerging as pivotal elements in accelerating wound healing. As we navigate the frontiers of nanotechnology, ongoing research illuminates promising avenues for further advancements, assuring a future where orthopedic practices are not only personalized but also highly efficient, promising a captivating journey through groundbreaking innovations and tailored patient care.

An update on the advances in the field of nanostructured drug delivery systems for a variety of orthopedic applications

Nanotechnology has made significant progress in various fields, including medicine, in recent times. The application of nanotechnology in drug delivery has sparked a lot of research interest, especially due to its potential to revolutionize the field. Researchers have been working on developing nanomaterials with distinctive characteristics that can be utilized in the improvement of drug delivery systems (DDS) for the local, targeted, and sustained release of drugs. This approach has shown great potential in managing diseases more effectively with reduced toxicity. In the medical field of orthopedics, the use of nanotechnology is also being explored, and there is extensive research being conducted to determine its potential benefits in treatment, diagnostics, and research. Specifically, nanophase drug delivery is a promising technique that has demonstrated the capability of delivering medications on a nanoscale for various orthopedic applications. In this article, we will explore current advancements in the area of nanostructured DDS for orthopedic use.

A mini-review on the emerging role of nanotechnology in revolutionizing orthopedic surgery: challenges and the road ahead

An emerging application of nanotechnology in medicine currently being developed involves employing nanoparticles to deliver drugs, heat, light, or other substances to specific types of cells (such as cancer cells). As most biological molecules exist and function at the nanoscale, engineering and manipulating matter at the molecular level has many advantages in the field of medicine (nanomedicine). Although encouraging, it remains unclear how much of this will ultimately result in improved patient care. In surgical specialties, clinically relevant nanotechnology applications include the creation of surgical instruments, suture materials, imaging, targeted drug therapy, visualization methods, and wound healing techniques. Burn lesion and scar management is an essential nanotechnology application. Prevention, diagnosis, and treatment of numerous orthopedic conditions are crucial technological aspects for patients' functional recovery. Orthopedic surgery is a specialty that deals with the diagnosis and treatment of musculoskeletal disorders. In recent years, the field of orthopedics has been revolutionized by the advent of nanotechnology. Using biomaterials comprised of nanoparticles and structures, it is possible to substantially enhance the efficacy of such interactions through nanoscale material modifications. This serves as the foundation for the majority of orthopedic nanotechnology applications. In orthopedic surgery, nanotechnology has been applied to improve surgical outcomes, enhance bone healing, and reduce complications associated with orthopedic procedures. This mini-review summarizes the present state of nanotechnology in orthopedic surgery, including its applications as well as possible future directions.

Ultrasound Responsive Smart Implantable Hydrogels for Targeted Delivery of Drugs: Reviewing Current Practices

Over the last two decades, the process of delivering therapeutic drugs to a patient with a controlled release profile has been a significant focus of drug delivery research. Scientists have given tremendous attention to ultrasound-responsive hydrogels for several decades. These smart nanosystems are more applicable than other stimuli-responsive drug delivery vehicles (ie UV-, pH- and thermal-, responsive materials) because they enable more efficient targeted treatment via relatively non-invasive means. Ultrasound (US) is capable of safely transporting energy through opaque and complex media with minimal loss of energy. It is capable of being localized to smaller regions and coupled to systems operating at various time scales. However, the properties enabling the US to propagate effectively in materials also make it very difficult to transform acoustic energy into other forms that may be used. Recent research from a variety of domains has attempted to deal with this issue, proving that ultrasonic effects can be used to control chemical and physical systems with remarkable specificity. By obviating the need for multiple intravenous injections, implantable US responsive hydrogel systems can enhance the quality of life for patients who undergo treatment with a varied dosage regimen. Ideally, the ease of self-dosing in these systems would lead to increased patient compliance with a particular therapy as well. However, excessive literature has been reported based on implanted US responsive hydrogel in various fields, but there is no comprehensive review article showing the strategies to control drug delivery profile. So, this review was aimed at discussing the current strategies for controlling and targeting drug delivery profiles using implantable hydrogel systems.

Multifunctional bone cement for synergistic magnetic hyperthermia ablation and chemotherapy of osteosarcoma

Myelosuppression, gastrointestinal toxicity and hypersensitivities always accompany chemotherapy of osteosarcoma (OS). In addition, the intricate karyotype of OS, the lack of targeted antitumor drugs and the bone microenvironment that provides a protective alcove for tumor cells reduce the therapeutic efficacy of chemotherapy. Here, we developed a multifunctional bone cement loaded with Fe₃O₄ nanoparticles and the antitumor drug doxorubicin (DOX/Fe₃O₄@PMMA) for synergistic MH ablation and chemotherapy of OS. The localized intratumorally administered DOX/Fe₃O₄@PMMA can change from liquid into solid at the tumor site via a polyreaction. The designed multifunctional bone cement was constructed with Fe₃O₄ nanoparticles, PMMA, and an antitumor drug approved by the U.S. Food and Drug administration (FDA). The injectability, magnetic hyperthermia (MH) performance, controlled drug release profile, and synergistic therapeutic effect of DOX/Fe₃O₄@PMMA in vitro were investigated in detail. Furthermore, the designed DOX/Fe₃O₄@PMMA controlled the release of DOX, enhanced the apoptosis of OS tissue, and inhibited the proliferation of tumor cells, demonstrating synergistic MH ablation and chemotherapy of OS in vivo. The biosafety of DOX/Fe₃O₄@PMMA was also evaluated in detail. This strategy significantly reduced surgical time, avoided operative wounds and prevented patient pain, showing a great clinical translational potential for OS treatment.

An artificially engineered "tumor bio-magnet" for collecting blood-circulating nanoparticles and magnetic hyperthermia

It is a great challenge to directly endow a tumor with specific functions for theranostic treatment. In this study, we report on a novel approach to transform a tumor into a "bio-magnet", to be magnetized on demand, in order to create an intrinsic tumor magnetic field that would collect magnetic nanoparticles (MNPs) circulating in the blood and achieve simultaneous magnetic hyperthermia. This was achieved by the localized intratumoral injection of liquid Nd2Fe14B/Fe3O4-PLGA, followed by solvent exchange that induces a liquid-to-solid transformation. After the magnetism charging process, the solid Nd2Fe14B/Fe3O4-PLGA implant was endowed with permanent magnetic properties and in situ created the magnetic field within the tumor tissue, making the tumor a "bio-magnet". After the creation of the bio-magnet, intravenously injected MNPs accumulated into the tumor tissue due to the tumor magnetic field. Importantly, both the in vitro and ex vivo results demonstrated the high efficiency of the implanted bio-magnet for magnetic hyperthermia. This new approach achieves magnetic targeting by creating a tumor "bio-magnet", which generates a strong magnetic field within the tumor, paving a new way for the development of an efficient targeting strategy for tumor therapy.

Injectable and thermally contractible hydroxypropyl methyl cellulose/Fe3O4 for magnetic hyperthermia ablation of tumors

The development of efficient strategies for the magnetic hyperthermia ablation of tumors remains challenging. To overcome the significant safety limitations, we developed a thermally contractible, injectable and biodegradable material for the minimally invasive and highly efficient magnetic hyperthermia ablation of tumors. This material was composed of hydroxypropyl methyl cellulose (HPMC), polyvinyl alcohol (PVA) and Fe₃O₄. The thermal contractibility of HPMC/Fe₃O₄ was designed to avoid damaging the surrounding normal tissue upon heating, which was confirmed by visual inspection, ultrasound imaging and computed tomography (CT). The efficient injectability of HPMC/Fe₃O₄ was proven using a very small needle. The biosafety of HPMC/Fe₃O₄ was evaluated by MTT and biochemical assays as well as flow cytometry (FCM). All the aforementioned data demonstrated the safety of HPMC/Fe₃O₄. The results of in vitro and ex vivo experiments showed that the temperature and necrotic volume of excised bovine liver were positively correlated with the HPMC/Fe₃O₄ weight, iron content and heating duration. The in vivo experimental results showed that the tumors could be completely ablated using 0.06 ml of HPMC/60%Fe₃O₄ after 180 s of induction heating. We believe that this novel, safe and biodegradable material will promote the rapid bench-to-bed translation of magnetic hyperthermia technology, and it is also expected to bring a new concept for the biomaterial research field.

Nanotechnology in orthopedics

Nanotechnology has revolutionized science and consumer products for several decades. Most recently, its applications to the fields of medicine and biology have improved drug delivery, medical diagnostics, and manufacturing. Recent research of this modern technology has demonstrated its potential with novel forms of disease detection and intervention, particularly within orthopedics. Nanomedicine has transformed orthopedics through recent advances in bone tissue engineering, implantable materials, diagnosis and therapeutics, and surface adhesives. The potential for nanotechnology within the field of orthopedics is vast and much of it appears to be untapped, though not without accompanying obstacles.

Highly efficient magnetic hyperthermia ablation of tumors using injectable polymethylmethacrylate–Fe3O4

Magnetic hyperthermia is a promising minimally invasive technique for tumor therapy which has drawn much attention.

MiRNA 34a: a therapeutic target for castration-resistant prostate cancer

INTRODUCTION

Development of a therapy for bone metastases is of paramount importance for castration-resistant prostate cancer (CRPC). The osteomimetic properties of CRPC confer a propensity to metastasize to osseous sites. Micro-ribonucleic acid (miRNA) is non-coding RNA that acts as a post-transcriptional regulator of multiple proteins and associated pathways. Therefore identification of miRNAs could reveal a valid third generation therapy for CRPC.

AREAS COVERED

miR34a has been found to play an integral role in the progression of prostate cancer, particularly in the regulation of metastatic genes involved in migration, intravasation, extravasation, bone attachment and bone homeostasis. The correlation between miR34a down-regulation and metastatic progression has generated substantial interest in this field.

EXPERT OPINION

Examination of the evidence reveals that miR34a is an ideal target for gene therapy for metastatic CRPC. We also conclude that future studies should focus on the effects of miR34a upregulation in CRPC with respect to migration, translocation to bone micro-environment and osteomimetic phenotype development. The success of miR34a as a therapeutic is reliant on the development of appropriate delivery systems and targeting to the bone micro-environment. In tandem with any therapeutic studies, biomarker serum levels should also be ascertained as an indicator of successful miR34a delivery.

Magnetic Hyperthermia Ablation of Tumors Using Injectable Fe₃O₄/Calcium Phosphate Cement

In this work, we have developed an injectable and biodegradable material using CPC containing Fe3O4 nanoparticles for minimally invasive and efficiently magnetic hyperthermia ablation of tumors. When exposed to an alternating magnetic field, the MCPC could quickly generate heat. The temperature of PBS and the excised bovine liver increased with the MCPC weight, iron content, and time. The ablated liver tissue volume for 0.36 g of 10% MCPC was 0.2 ± 0.03, 1.01 ± 0.07, and 1.96 ± 0.19 cm(3), respectively, at the time point of 60, 180, and 300 s. In our in vivo experiment, the MCPC could be directly injected into the center of the tumors under the guidance of ultrasound imaging. The formed MCPC was well-restricted within the tumor tissues without leakage, and the tumors were completely ablated by 0.36 g of 10% injectable MCPC after 180 s of induction heating.

Injectable smart phase-transformation implants for highly efficient in vivo magnetic-hyperthermia regression of tumors

A minimally invasive, highly efficient and versatile strategy is proposed for localized tumor regression by developing a smart injectable liquid-solid phase-transformation organic-inorganic hybrid composite material, i.e., magnetic-Fe-powder-dispersed PLGA (Fe/PLGA) implants for magnetic hyperthermia therapy of cancer.