Co-delivery of cisplatin and doxorubicin from calcium phosphate beads/matrix scaffolds for osteosarcoma therapy

Strategically Designed Bifunctional Polydopamine Enwrapping Polycaprolactone-Hydroxyapatite-Doxorubicin Composite Nanofibers for Osteosarcoma Treatment and Bone Regeneration

This study presents a new multifunctional nanofibrous drug delivery system to provide effective combination therapy with enormous potential for the treatment of osteosarcoma. We developed a composite nanofiber scaffold comprising poly(ε-caprolactone) (PCL) and hydroxyapatite (HAp)-loaded doxorubicin (DOX) coated with polydopamine (PDA) to combine cancer cell inhibition with bone tissue regeneration. DOX was conjugated with HAp and then mixed with a PCL solution to prepare a PCL/HAp-DOX (labeled PCLDH) nanofiber. Then, in situ polymerization of PDA on the PCLDH occurred to produce the PCLDH@PDA composite nanofiber. The morphology, XRD, FT-IR, wettability, photothermal characteristics, cumulative drug release, and in vitro bioactivities were evaluated. We found that the PDA coating not only enhanced the hydrophilic properties but also controlled drug release. The PCLDH@PDA composite scaffold significantly suppressed the proliferation of bone cancer cells initially and, consequently, improved the adhesion and proliferation of human mesenchymal stem cells (hMSCs). The PDA coating boosted the composite scaffold's bioactivity, as demonstrated through ALP activity, ARS assay, and biomineralization results. This strategy offers a promising dual-function scaffold to treat residual cancer and reconstruct defects after osteosarcoma surgery.

Calcium-based biomaterials: Unveiling features and expanding applications in osteosarcoma treatment

Calcium, an indispensable element in bone tissues, plays a crucial role in various cellular processes involved in cancer progression. Its ubiquitous yet spatially distinct distribution in the body presents an opportunity to target calcium homeostasis as a novel strategies for cancer treatment, with specific advantages in osteosarcoma therapy. In this comprehensive review, we retrospect the calcium biology intersected with cancer progression, highlight the unveiling features of calcium-based biomaterials in regulating both bone homeostasis and cancer development. We also provide an overview of recent breakthroughs in cancer therapy that leverage calcium biomaterials, showcasing their potential to serve as versatile, customizable platforms for osteosarcoma treatment and as reservoirs for supporting bone reconstruction.

Functional anti-bone tumor biomaterial scaffold: construction and application

Bone tumors, including primary bone tumors and bone metastases, have been plagued by poor prognosis for decades. Although most tumor tissue is removed, clinicians are still confronted with the dilemma of eliminating residual cancer cells and regenerating defective bone tissue after surgery. Therefore, functional biomaterial scaffolds are considered to be the ideal candidates to bridge defective tissues and restrain cancer recurrence. Through functionalized structural modifications or coupled therapeutic agents, they provide sufficient mechanical strength and osteoinductive effects while eliminating cancer cells. Numerous novel approaches such as photodynamic, photothermal, drug-conjugated, and immune adjuvant-assisted therapies have exhibited remarkable efficacy against tumors while exhibiting low immunogenicity. This review summarizes the progress of research on biomaterial scaffolds based on different functionalization strategies in bone tumors. We also discuss the feasibility and advantages of the combined application of multiple functionalization strategies. Finally, potential obstacles to the clinical translation of anti-tumor bone bioscaffolds are highlighted. This review will provide valuable references for future advanced biomaterial scaffold design and clinical bone tumor therapy.

Calcium phosphate bone cements as local drug delivery systems for bone cancer treatment

Bone cancer is usually a metastatic disease, affecting people of all ages. Its effective therapy requires a targeted drug administration locally at the cancer site so that the surrounding healthy organs and tissues stay unharmed. Upon a thorough literature search, a tremendous number of published articles are reporting on development of calcium phosphate cements (CPCs) for the treatment of a variety of diseases, such as osteoporosis, osteoarthritis, osteomyelitis, and other musculoskeletal disorders. However, just a limited number of research employs CPCs specifically for bone cancer treatment. In this review article, we study the factors influencing the local drug release from CPCs and particularly focus on bone cancer therapy. Finally, we locate the deficiencies in the literature regarding this specific topic and propose which other perspectives should be considered and discussed in future articles.

Synthetic biodegradable polymer materials in the repair of tumor-associated bone defects

The repair and reconstruction of bone defects and the inhibition of local tumor recurrence are two common problems in bone surgery. The rapid development of biomedicine, clinical medicine, and material science has promoted the research and development of synthetic degradable polymer anti-tumor bone repair materials. Compared with natural polymer materials, synthetic polymer materials have machinable mechanical properties, highly controllable degradation properties, and uniform structure, which has attracted more attention from researchers. In addition, adopting new technologies is an effective strategy for developing new bone repair materials. The application of nanotechnology, 3D printing technology, and genetic engineering technology is beneficial to modify the performance of materials. Photothermal therapy, magnetothermal therapy, and anti-tumor drug delivery may provide new directions for the research and development of anti-tumor bone repair materials. This review focuses on recent advances in synthetic biodegradable polymer bone repair materials and their antitumor properties.

Management of bone diseases: looking at scaffold-based strategies for drug delivery

The bone tissue can regenerate itself completely and continuously; however, large-scale bone defects may overpower this self-regenerative process. Furthermore, the aging population, the increment in obesity incidence, and the sedentary lifestyles are serious risk factors for bone diseases' development which are associated with the self-regenerative process's failure, high morbidity, and mortality rates. Thus, there is an ever-growing need for strategic approaches targeting bone replacement, its remodelling, and its regeneration. Bone scaffolds have successfully been used as synthetic bone grafts for many years, yet recent bone tissue engineering strategies attempt to explore their multifunctionality by investigating them as drug delivery systems. Bone diseases' treatments can be substantially difficult due to the avascular nature of the surrounding cartilage; thus, targeted drug delivery to the bone can be advantageous: it provides local high drug concentrations and minimizes adverse effects while securing a space for new, healthy tissue growth. Despite the promising scientific progress, studies underlining bone scaffolds' use as local drug delivery systems are not abundant. Hence, this work reviews bone scaffolds' therapeutic interest for local drug delivery in five distinct bone disorders-osteomyelitis, osteoporosis, osteoarthritis, osteosarcoma, and cancer bone metastasis. Additionally, it presents the challenges of this possible therapeutic approach and its future perspectives. Albeit bone scaffolds present therapeutic benefits by acting as drug delivery systems, further pre-clinical and clinical assessments are needed to strengthen their understanding and enable research evidence translation into clinical practice. The mismatch between scientific evolution and regulatory frameworks remains one of the major future challenges.

Decellularized adipose tissue matrix-coated and simvastatin-loaded hydroxyapatite microspheres for bone regeneration

Simvastatin (SIM)-loaded and human decellularized adipose tissue (DAT)-coated porous hydroxyapatite (HAp) microspheres were developed for the first time to investigate their potential on bone regeneration. Microspheres were loaded with SIM and then coated with DAT for modifying SIM release and improving their biological response. HAp microspheres were prepared by water-in-oil emulsion method using camphene (C₁₀ H₁₆ ) as porogen followed by camphene removal by freeze-drying and sintering at 1200°C for 3 h. Sintered HAp microspheres with an average particle size of ~400 µm were porous and spherical in shape. Microspheres were incubated with 1, 2.5, and 5 mg/ml SIM stock solutions for drug loading, and drug loading was determined as 7.5 ± 0.79, 20.41 ± 1.93, and 46.26 ± 0.29 µg SIM/mg microspheres, respectively. SIM loading increased with the increase of the initial SIM loading amount. Faster SIM release was observed in DAT-coated microspheres compared to bare counterparts. Higher SaoS-2 cell attachment and proliferation were observed on DAT-coated microspheres. Significantly higher alkaline phosphatase activity of SaoS-2 cells was observed on DAT-coated microspheres containing 0.01 mg/ml SIM than all other groups (p < 0.01). DAT-coated microspheres loaded with SIM at low doses hold promise for bone tissue engineering applications.

Bifunctional scaffolds for tumor therapy and bone regeneration: Synergistic effect and interplay between therapeutic agents and scaffold materials

Bone tumor patients often face the problems with cancer cell residues and bone defects after the operation. Therefore, researchers have developed many bifunctional scaffolds with both tumor treatment and bone repair functions. Therapeutic agents are usually combined with bioactive scaffolds to achieve the "bifunctional". However, the synergistic effect of bifunctional scaffolds on tumor therapy and bone repair, as well as the interplay between therapeutic agents and scaffold materials in bifunctional scaffolds, have not been emphasized and discussed. This review proposes a promising design scheme for bifunctional scaffolds: the synergistic effect and interplay between the therapeutic agents and scaffold materials. This review summarizes the latest research progress in bifunctional scaffolds for therapeutic applications and regeneration. In particular, it summarizes the role of tumor therapeutic agents in bone regeneration and the role of scaffold materials in tumor treatment. Finally, a perspective on the future development of bifunctional scaffolds for tumor therapy and bone regeneration is discussed.

Using scaffolds as drug delivery systems to treat bone tumor

Surgery is the principal strategy to treat osteosarcoma and other types of bone tumors, but it causes bone defects that cannot be healed spontaneously. After surgery, patients still need to receive radiotherapy and/or chemotherapy to prevent tumor recurrence and metastasis, which leads to systemic side effects. Bone scaffolds exhibit the potentials to load cargos (drugs or growth factors) and act as drug delivery systems (DDSs) in the osteosarcoma postoperative treatment. This review introduces current types of bone scaffolds and highlights representative works using scaffolds as DDSs to treat osteosarcomas. Challenges and perspectives in the scaffold-based DDSs are also discussed. This review may provide references to develop effective and safe strategies for osteosarcoma postoperative treatment.

Calcium Phosphate-Based Bioceramics in the Treatment of Osteosarcoma: Drug Delivery Composites and Magnetic Hyperthermia Agents

The use of biomaterials in medicine is not recent, and in the last few decades, the research and development of biocompatible materials had emerged. Hydroxyapatite (HAp), a calcium phosphate that constitutes a large part of the inorganic composition of human bones and teeth, has been used as an interesting bioceramic material. Among its applications, HAp has been used to carry antitumor drugs, such as doxorubicin, cisplatin, and gemcitabine. Such HAp-based composites have an essential role in anticancer drug delivery systems, including the treatment of osteosarcoma. In addition, the association of this bioceramic with magnetic nanoparticles (MNPs) has also been used as an effective agent of local magnetic hyperthermia. Further, the combined approach of the aforementioned techniques (HAp scaffolds combined with anti-tumor drugs and MNPs) is also an attractive therapeutical alternative. Considering the promising role of the use of bioceramics in modern medicine, we proposed this review, presenting an updated perspective on the use of HAp in the treatment of cancer, especially osteosarcoma. Finally, after giving the current progress in this field, we highlight the urgent need for efforts to provide a better understanding of their potential applications.

Development of a pH-sensitive functionalized metal organic framework: in vitro study for simultaneous delivery of doxorubicin and cyclophosphamide in breast cancer

Exploration of an efficient dual-drug based nanocarrier with high drug loading capacity, specific targeting properties, and long-term stability is highly desirable in cancer therapy. Metal-organic frameworks (MOFs) have proven to be a promising class of drug carriers due to their high porosity, crystalline properties with defined structure information, and their potential for further functionalization. To enhance the drug efficacy as well as to overcome the burst effect of drugs, here we synthesized a pH responsive folic acid (FA) and graphene oxide (GO) decorated zeolitical imidazolate frameworks-8 (GO-FA/ZIF-8), for targeted delivery of doxorubicin (DOX) and cyclophosphamide (CP), simultaneously. In this system, DOX molecules were encapsulated in the pores of ZIF-8 during in situ synthesis of ZIF-8 and CP molecules have been captured by the GO surface via hydrogen bonding and π-π interactions as well. Furthermore, the resulting pH-responsive nanocarrier (DOX@ZIF-8/GO-FA/CP) showed in vitro sustained release characteristics (76% of DOX and 80% of CP) by cleavage of chemical bonding and disruption of the MOFs structure under acidic condition (at pH 5.6). Moreover, DOX@ZIF-8/GO-FA/CP has synergistic cytotoxic effects as compared to the combination of both the drugs without ZIF-8/GO-FA when treating MCF-7 and MDA-MB-231 breast cancer cell lines (with a combination index of 0.29 and 0.75 for MCF-7 and MDA-MB-231 cell-lines, respectively). Hence this system can be applied as an effective platform for smart dual drug delivery in breast cancer treatment through its remarkable manageable multidrug release.

Progress of biomaterials for bone tumor therapy

Bone tumors are currently a major clinical challenge. In recent decades, strategies using well-designed versatile biomaterials for the treatment of bone tumors have emerged and attracted extensive research interest. Suitable biomaterials not only facilitate repair for bone defects aroused by surgical intervention but also help deliver antineoplastic drugs to the target site or provide photothermal/magnetothermal therapy to kill bone tumor cells. Thus, the development of biomaterials exhibits a great perspective for future bone tumor treatment.We summarize the recent progress of versatile biomaterials for bone tumor therapy, with an emphasis on photothermal/magnetothermal therapy and drug delivery.With the further understanding and development of biomaterials, multifunctional biomaterials have been proposed for bone tumor treatment. Through the interdisciplinary cooperation from the fields of biomedicine, clinical medicine and engineering, multifunctional biomaterials will perfectly match individual bone defects in the clinic with low cost in the future.

Nanocarrier-based drug delivery systems for bone cancer therapy: a review

Bone cancer is a malignant tumor that originates in the bone and destroys the healthy bone tissues. Of the various types of bone tumors, osteosarcoma is the most commonly diagnosed primary bone malignancy. The standard treatment for primary malignant bone tumors comprises surgery, chemotherapy and radiotherapy. Owing to the lack of proven treatments, different forms of alternative therapeutic approaches have been examined in recent decades. Among the new therapeutic methodologies, nanotechnology-based anticancer therapy has paved the way for new targeted strategies for bone cancer treatment and bone regeneration. They include approaches such as the co-delivery of multiple drug cargoes, the enhancement of their biodistribution and transport properties, normalizing accumulation and the optimization of drug release profiles to overcome shortcomings of the existing therapy. This review examines the standard treatments for osteosarcoma, their lacunae, and the evolving therapeutic strategies based on nanocarrier-mediated combinational drug delivery systems, and future perspectives for osteosarcoma therapy.

TCP/PLGA composite scaffold loaded rapamycin in situ enhances lumbar fusion by regulating osteoblast and osteoclast activity

The purpose of this study was to develop a novel β-tricalcium phosphate (TCP)/poly (D,L-lactic-co-glycolic acid) (PLGA) composite scaffold loaded with rapamycin that can regulate the activity of osteoblasts and osteoclasts for lumbar fusion. The TCP/PLGA composite scaffold was fabricated by cryogenic three-dimensional printing techniques and then loaded with rapamycin in situ. The structural surface morphology of the composite scaffold was tested with scanning electron microscope. To evaluate the biocompatibility of the composite scaffold in vitro, bone marrow mesenchymal stem cells (BMSCs) were cultured on the TCP/PLGA composite scaffold slide and tested with Live/Dead Viability Kit. The effect of rapamycin on osteoclast and osteoblast was studied with staining and Western blotting. The in vitro results showed that the rapamycin-loaded TCP/PLGA composite scaffold showed good biocompatibility with BMSC and released rapamycin obviously promoted the osteoblast differentiation and mineralization. In vivo study, the TCP/PLGA composite scaffold loaded with rapamycin were implanted in lumbar fusion model and study with micro-computed tomography scanning, hematoxylin-eosin, Masson, and immune-histological staining, to evaluate the effect of rapamycin on bone fusion. The in vivo results demonstrated that rapamycin-loaded TCP/PLGA composite scaffold could enhance bone formation by regulating osteoblast and osteoclast activity, respectively. In this study, the TCP/PLGA composite scaffold loaded with rapamycin was confirmed to provide great compatibility and improved performance in lumbar fusion by regulating osteoblastic and osteoclastic activity and would be a promising composite biomaterial for bone tissue engineering.

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.

Design strategies and evolving role of biomaterial assisted treatment of osteosarcoma

Osteosarcoma is the most commonly diagnosed form of bone cancer. It is characterized by a high risk of developing lung metastasis as the disease progresses. Standard treatment includes combination of surgical intervention, chemotherapy and radiotherapy. However, the non-specificity of potent chemotherapeutic agents often leads to major side effects. In this review, we discuss the role of various classes of biomaterials, including both organic as well as inorganic in realizing the local and systemic delivery of therapeutic agents like drugs, radioisotopes and even gene silencing agents to treat osteosarcoma. Biomaterial assisted unconventional therapies such as targeted therapy, nanotherapy, magnetic hyperthermia, gene therapy, photothermal and photodynamic therapies are also being explored. A wide variety of biomaterials including lipids, carbon-based materials, polymers, silica, bioactive glass, hydroxyapatite and metals are designed as delivery systems with the desired loading efficiency, release profile, and on-demand delivery. Among others, liposomal carriers have attracted a great deal of attention due to their capability to encapsulate both hydrophobic and hydrophilic drugs. Polymeric systems have high drug loading efficiency and stability and can even be tailored to achieve desired size and physiochemical properties. Carbon-based systems can also be seen as an upcoming class of therapeutics with great potential in treating different types of cancer. Inorganic materials like silica nanoparticles have high drug payload owing to their mesoporous structure. On the other hand, ceramic materials like bioactive glass and hydroxyapatite not only act as excellent delivery vectors but also participate in osteo-regeneration activity. These multifunctional biomaterials are also being investigated for their theranostic abilities to monitor cancer ablation. This review systematically discusses the vast landscape of biomaterials along with their challenges and respective opportunities for osteosarcoma therapy.

Dual-functional scaffolds of poly(L-lactic acid)/nanohydroxyapatite encapsulated with metformin: Simultaneous enhancement of bone repair and bone tumor inhibition

Bone defects caused by tumors are difficult to repair clinically because of their poor morphology and residual tumor cell-induced recurrence. Scaffolds with the dual function of bone repair and bone tumor treatment are urgently needed to resolve this problem. In this study, a poly(L-lactic acid) (PLLA)/nanoscale hydroxyapatite (nHA)/metformin (MET) nanocomposite scaffold was constructed via selective laser sintering. The scaffolds were expected to combine the excellent mechanical strength and biodegradability of PLLA, the good bioactivity of nHA, and the water solubility and antitumor properties of MET. The PLLA/nHA/MET scaffolds showed improved cell adhesion, appropriate porosity, good biocompatibility and osteogenic-induced ability in vitro because metformin improves water solubility and promotes the osteogenic differentiation of cells within the scaffold. The PLLA/nHA/MET scaffold had an extended drug release time because the MET particles were wrapped in the biodegradable polymer PLLA and the wrapped MET particles were slowly released into body fluids as the PLLA was degraded. Moreover, the scaffold induced osteosarcoma (OS) cell apoptosis by upregulating apoptosis-related gene expression and showed excellent tumor inhibition characteristics in vitro. In addition, the scaffold induced osteogenic differentiation of bone marrow mesenchymal cells (BMSCs) by promoting osteogenic gene expression. The results suggest that the PLLA/nHA/MET composite scaffold has the dual function of tumor inhibition and bone repair and therefore it provides a promising new approach for the treatment of tumor-induced bone defects.

Bone Diseases: Current Approach and Future Perspectives in Drug Delivery Systems for Bone Targeted Therapeutics

Bone diseases include a wide group of skeletal-related disorders that cause mobility limitations and mortality. In some cases, e.g., in osteosarcoma (OS) and metastatic bone cancer, current treatments are not fully effective, mainly due to low patient compliance and to adverse side effects. To overcome these drawbacks, nanotechnology is currently under study as a potential strategy allowing specific drug release kinetics and enhancing bone regeneration. Polymers, ceramics, semiconductors, metals, and self-assembled molecular complexes are some of the most used nanoscale materials, although in most cases their surface properties need to be tuned by chemical or physical reactions. Among all, scaffolds, nanoparticles (NPs), cements, and hydrogels exhibit more advantages than drawbacks when compared to other nanosystems and are therefore the object of several studies. The aim of this review is to provide information about the current therapies of different bone diseases focusing the attention on new discoveries in the field of targeted delivery systems. The authors hope that this paper could help to pursue further directions about bone targeted nanosystems and their application for bone diseases and bone regeneration.

Electrosprayed poly(lactic-co-glycolic acid) particles as a promising drug delivery system for the novel JNK inhibitor IQ-1

Mitogen-activated protein kinases (MAPKs), including c-Jun N-terminal kinase (JNK), play important role in the regulation of pro-inflammatory cytokine secretion and signaling cascades. Therefore, JNKs are key targets for the treatment of cytokine/JNK-driven diseases. Herein, we developed electrospray poly(lactic-co-glycolic acid) (PLGA) microparticles doped with novel JNK inhibitor 11H-indeno[1,2-b]quinoxalin-11-one oxime (IQ-1). Optimized electrospray parameters allowed us to produce IQ-1-doped microparticles with round shape, smooth and non-porous surface, and mean diameter of 0.9-1.3 μm. We have shown that IQ-1 was well integrated into the polymer matrix and had a prolonged release in two steps via non-Fickian release. The fabricated particles doped with IQ-1 exhibited anti-inflammatory effects, as indicated by inhibited neutrophil activation and cytokine secretion by human monocytic MonoMac-6 cells. Overall, our study demonstrates that PLGA microparticles doped with a novel JNK inhibitor (IQ-1) could be a promising delivery system for treatment of JNK-mediated diseases.

Innovative Biomaterials for Bone Regrowth

The regenerative medicine, a new discipline that merges biological sciences and the fundamental of engineering to develop biological substitutes, has greatly benefited from recent advances in the material engineering and the role of stem cells in tissue regeneration. Regenerative medicine strategies, involving the combination of biomaterials/scaffolds, cells, and bioactive agents, have been of great interest especially for the repair of damaged bone and bone regrowth. In the last few years, the life expectancy of our population has progressively increased. Aging has highlighted the need for intervention on human bone with biocompatible materials that show high performance for the regeneration of the bone, efficiently and in a short time. In this review, the different aspects of tissue engineering applied to bone engineering were taken into consideration. The first part of this review introduces the bone cellular biology/molecular genetics. Data on biomaterials, stem cells, and specific growth factors for the bone regrowth are reported in this review.

Co-delivery of cisplatin and doxorubicin by covalently conjugating with polyamidoamine dendrimer for enhanced synergistic cancer therapy

Because of the synergistic effects of drugs and minimal drug dose for cancer therapy, combination chemotherapy is frequently used in the clinic. In this study, hyaluronic acid-modified amine-terminated fourth-generation polyamidoamine dendrimer nanoparticles were synthesized for systemic co-delivery of cisplatin and doxorubicin (HA@PAMAM-Pt-Dox). In vitro data showed that HA@PAMAM-Pt-Dox can enter the cells through the lysosome mediated-pathway in a time-dependent manner. Cell viability studies indicated that HA@PAMAM-Pt-Dox exhibited a higher anticancer activity on MCF-7 and MDA-MB-231 breast cancer cells at a relative low concentration. HA@PAMAM-Pt-Dox not only efficiently inhibited tumor growth but also significantly reduced the toxicity of Dox. Moreover, intravenous administration of HA@PAMAM-Pt-Dox to MDA-MB-231 tumor-bearing BALB/c nude mice resulted in the accumulation of HA@PAMAM-Pt-Dox at the tumor site, thereby significantly inhibiting tumor growth without apparent toxicity. These results suggested that HA@PAMAM-Pt-Dox has great potential to improve the chemotherapeutic efficacy of cisplatin and doxorubicin in breast cancer. STATEMENT OF SIGNIFICANCE: One of the main problems in cancer treatment is the development of drug resistance. To date, it is believed that combination chemotherapy might be an effective strategy for the above problem. However, for two completely different drugs, combination chemotherapy faces huge difficulties including the antagonistic nature of drugs, variations in drugs in terms of solubility, and limited tumor targeting. Recent developments in nanoscience and nanotechnology provide an effective approach for such disadvantages. Considering the advantages of dendrimers such as control of size and molecular weight, bioavailability, and biosafety, we used fourth-generation dendrimers modified by HA as drug vectors by covalently conjugating them with anticancer drugs (cisplatin and doxorubicin) to form a nanodrug delivery system, named HA@PAMAM-Pt-Dox. We observed that the HA@PAMAM-Pt-Dox system can effectively kill breast cancer cells both in vitro and in vivo, which showed a favorable synergistic effect. This strategy can be extended to other drugs, thus providing a highly effective strategy for cancer treatment.

Paclitaxel and etoposide-loaded Poly (lactic-co-glycolic acid) microspheres fabricated by coaxial electrospraying for dual drug delivery

In this study, we fabricated paclitaxel (PTX) and etoposide (ETP) loaded Poly (lactic-co-glycolic acid) (PLGA) microspheres with core-shell structures and particle sizes ranging from 1 to 4 µm by coaxial electrospraying. The microspheres were analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM). The drug loading rate and entrapment efficiency of the microspheres were detected by high performance liquid chromatograph (HPLC). Moreover, the drug release profiles and degradation of drug-loaded PLGA microspheres in vitro were investigated, respectively. The distinct layered structure that existed in the manufactured core-shell microspheres can be observed by TEM. The in vitro release profiles indicated that the PLGA/PTX + ETP (PLGA/PE) microspheres exhibited the controlled release of two drugs in a sequential manner. Cell Counting Kit-8 was used to detect the toxic and side effects of the microspheres on bone tumor cells. PTX and ETP for combination drug therapy loaded microspheres had more cytotoxic effect on saos-2 osteosarcoma cells than the individual drugs. In conclusion, core-shell PLGA microspheres by electrospraying for combination drug therapy is promising for medicine applications, the PLGA/PE microspheres have some potential for osteosarcoma treatment.

A New Porous Hybrid Material Derived From Silica Fume and Alginate for Sustainable Pollutants Reduction

In this work a new mesoporous adsorbent material obtained from a natural, high abundant raw material and a high volume industrial by-product is presented. The material is consolidated by the gelling properties of alginate and by decomposition of sodium-bicarbonate controlled porosity at low temperatures (70–80°C) at different scale lengths. The structural, thermal, and morphological characterization shows that the material is a mesoporous organic-inorganic hybrid. The material is tested as adsorbent, showing high performances. Methylene blue, used as model pollutant, can be adsorbed and removed from aqueous solutions even at a high concentration with efficiency up to 94%. By coating the material with a 100 nm thin film of titania, good photodegradation performance (more than 20%) can be imparted. Based on embodied energy and carbon footprint of its primary production, the sustainability of the new obtained material is evaluated and quantified in respect to activated carbon as well. It is shown that the new proposed material has an embodied energy lower than one order of magnitude in respect to the one of activated carbon, which represents the gold standards. The versatility of the new material is also demonstrated in terms of its design and manufacturing possibilities In addition, this material can be printed in 3D. Finally, preliminary results about its ability to capture diesel exhaust particulate matter are reported. The sample exposed to diesel contains a large amount of carbon in its surface. At the best of our knowledge, this is the first time that hybrid porous materials are proposed as a new class of sustainable materials, produced to reduce pollutants in the wastewaters and in the atmosphere.

Preparation of porous calcium phosphate microspheres with phosphate-containing molecules at room temperature for drug delivery and osteogenic differentiation

Calcium phosphate (CaP) has similar chemical properties to those of the inorganic component of human bone tissue, for potential application in drug delivery for the chemotherapy of osteosarcoma. In this work, CaP with a porous microsphere structure has been synthesized using fructose-1,6-bisphosphate (FBP) as the phosphorus source by a simple wet-chemical strategy at room temperature. The CaP porous microspheres, as an organic–inorganic hybrid nano-platform, exhibit good doxorubicin (Dox) loading capacity, and Dox-loading CaP, enhancing the in vitro chemotherapy of osteosarcoma cells. The CaP porous microspheres show high biocompatibility, and induce the osteogenic differentiation of MC3T3-E1. These results indicate that the CaP porous microspheres reported in this study are promising for application as an anti-osteosarcoma drug carrier and osteoinductive material for bone regeneration in the treatment of osteosarcoma.

Porous calcium phosphate microspheres were prepared at room temperature, and displayed potential for application in the chemotherapy of osteosarcoma and osteogenic differentiation.