Biomimetic Polydopamine-Modified Silk Fibroin/Curcumin Nanofibrous Scaffolds for Chemo-photothermal Therapy of Bone Tumor

Advances in the Application of Photothermal Composite Scaffolds for Osteosarcoma Ablation and Bone Regeneration

Photothermal therapy is a promising approach to cancer treatment. The energy generated by the photothermal effect can effectively inhibit the growth of cancer cells without harming normal tissues, while the right amount of heat can also promote cell proliferation and accelerate tissue regeneration. Various nanomaterials have recently been used as photothermal agents (PTAs). The photothermal composite scaffolds can be obtained by introducing PTAs into bone tissue engineering (BTE) scaffolds, which produces a photothermal effect that can be used to ablate bone cancer with subsequent further use of the scaffold as a support to repair the bone defects created by ablation of osteosarcoma. Osteosarcoma is the most common among primary bone malignancies. However, a review of the efficacy of different types of photothermal composite scaffolds in osteosarcoma is lacking. This article first introduces the common PTAs, BTE materials, and preparation methods and then systematically summarizes the development of photothermal composite scaffolds. It would provide a useful reference for the combination of tumor therapy and tissue engineering in bone tumor-related diseases and complex diseases. It will also be valuable for advancing the clinical applications of photothermal composite scaffolds.

Organic and Biogenic Nanocarriers as Bio-Friendly Systems for Bioactive Compounds' Delivery: State-of-the Art and Challenges

"Green" strategies to build up novel organic nanocarriers with bioperformance are modern trends in nanotechnology. In this way, the valorization of bio-wastes and the use of living systems to develop multifunctional organic and biogenic nanocarriers (OBNs) have revolutionized the nanotechnological and biomedical fields. This paper is a comprehensive review related to OBNs for bioactives' delivery, providing an overview of the reports on the past two decades. In the first part, several classes of bioactive compounds and their therapeutic role are briefly presented. A broad section is dedicated to the main categories of organic and biogenic nanocarriers. The major challenges regarding the eco-design and the fate of OBNs are suggested to overcome some toxicity-related drawbacks. Future directions and opportunities, and finding "green" solutions for solving the problems related to nanocarriers, are outlined in the final of this paper. We believe that through this review, we will capture the attention of the readers and will open new perspectives for new solutions/ideas for the discovery of more efficient and "green" ways in developing novel bioperformant nanocarriers for transporting bioactive agents.

Polydopamine functionalized polyurethane shape memory sponge with controllable expansion performance triggered by near-infrared light for incompressible hemorrhage control

Uncontrolled expansion of shape memory sponges face a significant challenge in the treatment of lethal incompressible hemorrhage, which can lead to blood overflow or damage to the surrounding tissue. Herein, we developed a polydopamine functionalized polyurethane shape memory sponge (PDA-TPI-PU) with a controllable degree of expansion by near-infrared (NIR) light-triggered stimulation for the treatment of incompressible hemorrhage. The sponge has excellent liquid absorption performance and robust mechanical strength as well as good photothermal conversion ability. Under NIR light of 0.32 W/cm2, the maximum recovery rate of the fixed-shape compression sponge was 91% within 25 s in air and 80% within 25 s in blood. In the SD rat liver penetrating injury model, compared with commercial medical gelatin sponge and PVA sponge, the PDA-TPI-PU sponge could effectively control the bleeding under the NIR light irradiation and did not cause excessive compression of the wound. The sponge with these characteristics shows potential application prospects as a hemostatic material.

Application of advanced biomaterials in photothermal therapy for malignant bone tumors

Malignant bone tumors are characterized by severe disability rate, mortality rate, and heavy recurrence rate owing to the complex pathogenesis and insidious disease progression, which seriously affect the terminal quality of patients' lives. Photothermal therapy (PTT) has emerged as an attractive adjunctive treatment offering prominent hyperthermal therapeutic effects to enhance the effectiveness of surgical treatment and avoid recurrence. Simultaneously, various advanced biomaterials with photothermal capacity are currently created to address malignant bone tumors, performing distinctive biological functions, including nanomaterials, bioceramics (BC), polymers, and hydrogels et al. Furthermore, PTT-related combination therapeutic strategies can provide more significant curative benefits by reducing drug toxicity, improving tumor-killing efficiency, stimulating anti-cancer immunity, and improving immune sensitivity relative to monotherapy, even in complex tumor microenvironments (TME). This review summarizes the current advanced biomaterials applicable in PTT and relevant combination therapies on malignant bone tumors for the first time. The multiple choices of advanced biomaterials, treatment methods, and new prospects for future research in treating malignant bone tumors with PTT are generalized to provide guidance. Malignant bone tumors seriously affect the terminal quality of patients' lives. Photothermal therapy (PTT) has emerged as an attractive adjunctive treatment enhancing the effectiveness of surgical treatment and avoiding recurrence. In this review, advanced biomaterials applicable in the PTT of malignant bone tumors and their distinctive biological functions are comprehensively summarized for the first time. Simultaneously, multiple PTT-related combination therapeutic strategies are classified to optimize practical clinical issues, contributing to the selection of biomaterials, therapeutic alternatives, and research perspectives for the adjuvant treatment of malignant bone tumors with PTT in the future.

High dose, dual-release polymeric films for extended surgical bed paclitaxel delivery

While surgery represents a major therapy for most solid organ cancers, local recurrence is clinically problematic for cancers such as sarcoma for which adjuvant radiotherapy and systemic chemotherapy provide minimal local control or survival benefit and are dose-limited due to off-target side effects. We describe an implantable, biodegradable poly(1,2-glycerol carbonate) and poly(caprolactone) film with entrapped and covalently-bound paclitaxel enabling safe, controlled, and extended local delivery of paclitaxel achieving concentrations 10,000× tissue levels compared to systemic administration. Films containing entrapped and covalently-bound paclitaxel implanted in the tumor bed, immediately after resection of human cell line-derived chondrosarcoma and patient-derived xenograft liposarcoma and leiomyosarcoma in mice, improve median 90- or 200-day recurrence-free and overall survival compared to control mice. Furthermore, mice in the experimental film arm show no film-related morbidity. Continuous, extended, high-dose paclitaxel delivery via this unique polymer platform safely improves outcomes in three different sarcoma models and provides a rationale for future incorporation into human trials.

Resorbable Membranes for Guided Bone Regeneration: Critical Features, Potentials, and Limitations

Lack of horizontal and vertical bone at the site of an implant can lead to significant clinical problems that need to be addressed before implant treatment can take place. Guided bone regeneration (GBR) is a commonly used surgical procedure that employs a barrier membrane to encourage the growth of new bone tissue in areas where bone has been lost due to injury or disease. It is a promising approach to achieve desired repair in bone tissue and is widely accepted and used in approximately 40% of patients with bone defects. In this Review, we provide a comprehensive examination of recent advances in resorbable membranes for GBR including natural materials such as chitosan, collagen, silk fibroin, along with synthetic materials such as polyglycolic acid (PGA), polycaprolactone (PCL), polyethylene glycol (PEG), and their copolymers. In addition, the properties of these materials including foreign body reaction, mechanical stability, antibacterial property, and growth factor delivery performance will be compared and discussed. Finally, future directions for resorbable membrane development and potential clinical applications will be highlighted.

Supercritical CO2-assisted fabrication of CM-PDA/SF/nHA nanofibrous scaffolds for bone regeneration and chemo-photothermal therapy against osteosarcoma

Concurrent treatment of tumor recurrence and bone defects after surgical resection of osteosarcoma remains a clinical challenge. Combination therapy based on local drug delivery systems shows great promise in the treatment of osteosarcoma. In this study, curcumin modified polydopamine nanoparticle loaded silk fibroin doped with nano-hydroxyapatite (CM-PDA/SF/nHA) nanofibrous scaffolds were developed to induce bone defect regeneration and chemo-photothermal synergistic effects against osteosarcoma. These scaffolds exhibited good photothermal conversion efficiency and photostability. Moreover, the results of ALP staining and alizarin red S (ARS) staining indicated that the CM-PDA/SF/1%nHA scaffolds had the most obvious promotion effect on early osteogenic differentiation. The results of in vitro and in vivo anti-osteosarcoma activity showed that the CM-PDA/SF/1%nHA scaffolds exhibited higher anti-osteosarcoma activity compared to the control and SF scaffolds. In addition, the CM-PDA/SF/1%nHA scaffolds could promote the proliferation and differentiation of bone marrow mesenchymal stem cells in vitro and new bone production in vivo. Thus, these results suggested that the CM-PDA/SF/1%nHA scaffolds could improve bone defect regeneration and achieve chemo-photothermal synergistic effects against osteosarcoma.

The Extracellular Matrix: Its Composition, Function, Remodeling, and Role in Tumorigenesis

The extracellular matrix (ECM) is a ubiquitous member of the body and is key to the maintenance of tissue and organ integrity. Initially thought to be a bystander in many cellular processes, the extracellular matrix has been shown to have diverse components that regulate and activate many cellular processes and ultimately influence cell phenotype. Importantly, the ECM's composition, architecture, and stiffness/elasticity influence cellular phenotypes. Under normal conditions and during development, the synthesized ECM constantly undergoes degradation and remodeling processes via the action of matrix proteases that maintain tissue homeostasis. In many pathological conditions including fibrosis and cancer, ECM synthesis, remodeling, and degradation is dysregulated, causing its integrity to be altered. Both physical and chemical cues from the ECM are sensed via receptors including integrins and play key roles in driving cellular proliferation and differentiation and in the progression of various diseases such as cancers. Advances in 'omics' technologies have seen an increase in studies focusing on bidirectional cell-matrix interactions, and here, we highlight the emerging knowledge on the role played by the ECM during normal development and in pathological conditions. This review summarizes current ECM-targeted therapies that can modify ECM tumors to overcome drug resistance and better cancer treatment.

Nanosized drug delivery strategies in osteosarcoma chemotherapy

Despite recent developments worldwide in the therapeutic care of osteosarcoma (OS), the ongoing challenges in overcoming limitations and side effects of chemotherapy drugs warrant new strategies to improve overall patient survival. Spurred by rapid progress in biomedicine, nanobiotechnology, and materials chemistry, chemotherapeutic drug delivery in treatment of OS has become possible in recent years. Here, we review recent advances in the design of drug delivery system, especially for chemotherapeutic drugs in OS, and discuss the relative merits in trials along with future therapeutic options. These advances may pave the way for novel therapies requisite for patients with OS.

Curcumin in human osteosarcoma: From analogs to carriers

Osteosarcoma (osteogenic sarcoma), the most prevalent primary malignant bone tumor in adolescents, confers low survival rates in patients with metastatic disease. Dietary curcumin has a number of anticancer properties but has poor bioavailability. To improve the clinical applications of curcumin, several potential curcumin analogs and nanobased curcumin delivery systems have been developed. In this critical review, we address the biological and pharmacological characteristics of curcumin and its analogs, with an emphasis on strategies to improve the bioactivity and bioavailability of curcumin analogs that may increase their application in the treatment of potent human metastatic osteosarcoma. We highlight promising current multifunctional nanoformulations and three-dimensional printed scaffold systems utilized for the targeting and delivery of curcumin in human osteosarcoma cells. Our purpose is to drive further research on curcumin analogs and carriers to improve their bioavailability and anti-osteosarcoma bioactivity.

Two Hawks with One Arrow: A Review on Bifunctional Scaffolds for Photothermal Therapy and Bone Regeneration

Despite the significant improvement in the survival rate of cancer patients, the total cure of bone cancer is still a knotty clinical challenge. Traditional surgical resectionof bone tumors is less than satisfactory, which inevitably results in bone defects and the inevitable residual tumor cells. For the purpose of realizing minimal invasiveness and local curative effects, photothermal therapy (PTT) under the irradiation of near-infrared light has made extensive progress in ablating tumors, and various photothermal therapeutic agents (PTAs) for the treatment of bone tumors have thus been reported in the past few years, has and have tended to focus on osteogenic bio-scaffolds modified with PTAs in order to break through the limitation that PTT lacks, osteogenic capacity. These so-called bifunctional scaffolds simultaneously ablate bone tumors and generate new tissues at the bone defects. This review summarizes the recent application progress of various bifunctional scaffolds and puts forward some practical constraints and future perspectives on bifunctional scaffolds for tumor therapy and bone regeneration: two hawks with one arrow.

Evaluation of cell adhesion and osteoconductivity in bone substitutes modified by polydopamine

Bones damaged due to disease or accidents can be repaired in different ways. Tissue engineering has helped with scaffolds made of different biomaterials and various methods. Although all kinds of biomaterials can be useful, sometimes their weakness in cellular activity or osteoconductivity prevents their optimal use in the fabrication of bone scaffolds. To solve this problem, we need additional processes, such as surface modification. One of the common methods is coating with polydopamine. Polydopamine can not only cover the weakness of the scaffolds in terms of cellular properties, but it can also create or increase osteoconductivity properties. Polydopamine creates a hydrophilic layer on the surface of scaffolds due to a large number of functional groups such as amino and hydroxyl groups. This layer allows bone cells to anchor and adheres well to the surfaces. In addition, it creates a biocompatible environment for proliferation and differentiation. Besides, the polydopamine coating makes the surfaces chemically active by catechol and amine group, and as a result of their presence, osteoconductivity increases. In this mini-review, we investigated the characteristics, structure, and properties of polydopamine as a modifier of bone substitutes. Finally, we evaluated the cell adhesion and osteoconductivity of different polydopamine-modified bone scaffolds.

Multifunctional 3D-printed bioceramic scaffolds: Recent strategies for osteosarcoma treatment

Osteosarcoma is the most prevalent bone malignant tumor in children and teenagers. The bone defect, recurrence, and metastasis after surgery severely affect the life quality of patients. Clinically, bone grafts are implanted. Primary bioceramic scaffolds show a monomodal osteogenesis function. With the advances in three-dimensional printing technology and materials science, while maintaining the osteogenesis ability, scaffolds become more patient-specific and obtain additional anti-tumor ability with functional agents being loaded. Anti-tumor therapies include photothermal, magnetothermal, old and novel chemo-, gas, and photodynamic therapy. These strategies kill tumors through novel mechanisms to treat refractory osteosarcoma due to drug resistance, and some have shown the potential to reverse drug resistance and inhibit metastasis. Therefore, multifunctional three-dimensional printed bioceramic scaffolds hold excellent promise for osteosarcoma treatments. To better understand, we review the background of osteosarcoma, primary 3D-printed bioceramic scaffolds, and different therapies and have a prospect for the future.

Curcumin and its Analogs and Carriers: Potential Therapeutic Strategies for Human Osteosarcoma

Curcumin is a natural polyphenol phytochemical derived from turmeric with antioxidant, anti-inflammatory, and anticancer properties but is concerned about poor solubility in water, absorption, and metabolic stability. Potent metastatic osteosarcoma is the most common primary bone cancer in children, adolescents, and young adults. It is responsible for low survival rates because of its high rate of metastasis to the lungs. To improve poor bioavailability, numerous curcumin analogs were developed to possess anticancer characteristics through a variety of biological pathways involved in cytotoxicity, proliferation, autophagy, sensitizing chemotherapy, and metastases. This review provides an overview of their various pharmacological functions, molecular mechanisms, and therapeutic potential as a remedy for human osteosarcoma. To enhance therapeutic efficacy, several liposomal nanoparticles, nanocarriers, multifunctional micelles, and three-dimensional printed scaffolds have also been developed for the controlled delivery of curcumin targeting human osteosarcoma cells. Consequently, curcumin and several potential analogs and delivery formulations are optimistic candidates to improve the currently available strategy for human osteosarcoma. However, further insight into the mechanism of action of promising curcumin analogs and the development of carriers in clinical trials of osteosarcoma needs to be investigated to improve their overall potency and clinical utility, in particular the anti-metastatic effect.

Supercritical Fluid-Assisted Fabrication of PDA-Coated Poly (l-lactic Acid)/Curcumin Microparticles for Chemo-Photothermal Therapy of Osteosarcoma

After traditional osteosarcoma resection, recurrence of tumor is still a major clinical challenge. The combination of chemotherapy and photothermal therapy (PTT) has great potential in improving therapeutic effect. However, the studies using polydopamine (PDA) as photothermal transducing agent to improve the anti-cancer activity of curcumin (CM)-loaded poly (l-lactic acid) (PLLA) microparticles (PLLA/CM) have seldom been investigated. In this study, we reported the synthesis of PDA-coated PLLA/CM microparticles (PDA-PLLA/CM) prepared by PDA coating on the surface of the PLLA/CM microparticles fabricated by solution-enhanced dispersion by supercritical CO2 (SEDS) for chemo-photothermal therapy of osteosarcoma. The average particle sizes of PLLA/CM and PDA-PLLA/CM microparticles with a spherical shape were (802.6 ± 8.0) nm and (942.5 ± 39.5) nm, respectively. PDA-PLLA/CM microparticles exhibited pH- and near-infrared (NIR)-responsive release behavior to promote CM release in the drug delivery system. Moreover, PDA-PLLA/CM microparticles displayed good photothermal conversion ability and photothermal stability attributed to PDA coating. Additionally, the results of in vitro anti-cancer experiment showed that 500 μg/mL PDA-PLLA/CM microparticles had good anti-cancer effect on MG-63 cells and no obvious toxicity to MC3T3-E1 cells. After incubation with PDA-PLLA/CM microparticles for 2 days, NIR irradiation treatment improved the anti-cancer activity of PDA-PLLA/CM microparticles obviously and reduced the cell viability of osteosarcoma from 47.4% to 20.6%. These results indicated that PDA-PLLA/CM microparticles possessed a synergetic chemo-photothermal therapy for osteosarcoma. Therefore, this study demonstrated that PDA-PLLA/CM microparticles may be an excellent drug delivery platform for chemo-photothermal therapy of tumors.