Gold nanoshell-based betulinic acid liposomes for synergistic chemo-photothermal therapy

Recent advancements of betulinic acid-based drug delivery systems for cancer therapy (2002-2023)

Betulinic acid, a compound classified as a pentacyclic triterpenoid, is found in abundance in a variety of medicinal plants and natural substances. Its broad spectrum of biological and medicinal properties, particularly its potent antitumor activity, has gained significant attention in recent years. The anticancer properties of betulinic acid are governed by mitochondrial signalling pathways and it exhibit selectivity for cancerous tissue, leaving non-cancerous cells and normal tissue unharmed. This characteristic is particularly valuable in chemo-resistant cases. Nevertheless, the medicinal potential of betulinic acid is hindered by its poor water solubility and short half-life, leading to sub-optimal effectiveness. This issue is being tackled by a variety of nano-sized drug delivery systems, such as polymeric nanoparticles, magnetic nanoparticles, polymeric conjugates, nanoemulsions, liposomes, nanosuspensions, carbon nanotubes, and cyclodextrin complexes. This article focuses on recent advances in nanoformulations that are tailored to the delivery of betulinic acid with enhanced effectiveness.

Chemosensitizer Loaded NIR-Responsive Nanostructured Lipid Carriers: A Tool for Drug-Resistant Breast Cancer Synergistic Therapy

Although numerous technical advances have been made in cancer treatment, chemotherapy is still a viable treatment option. However, it is more effective when used in combination with photothermal therapy for resistant breast cancer cells. This study introduces a smart drug delivery system, (DOX-OA+VERA+AuNRs)@NLC, which is designed for dual chemo/photothermal therapy of multiple-drug-resistant breast cancer. Type-III nanostructured lipid carriers (NLCs) were used as drug delivery systems, where nano-in-nano structures offer several advantages. Doxorubicin (DOX) was used as the antitumor agent by ion-pairing it with oleic acid (OA) to increase the DOX loading capacity, as well as to reduce the burst release of the drug. Verapamil (VERA), which was used as a chemosensitizer to overcome the multiple-drug resistance, was co-loaded with DOX-OA. Gold nanorods (AuNRs) were exploited as the photothermal therapy agent in photothermal therapy (PTT) application, which would have a synergistic relation with chemotherapy. The release of DOX-OA and VERA from NLCs was studied in vitro by triggering with NIR laser irradiation. Thus, an all-in-one drug delivery system was designed to release the active pharmaceutical ingredients (APIs) at higher concentrations in the desired region and provide both chemo/PTT. Besides, the application of a folic acid-chitosan (FA-CS) coating to NLCs has facilitated the development of systems capable of targeting and specifically releasing their cargo within cancerous tissues while preserving their surrounding environment.

Gold nanoparticles decorated FOLFIRINOX loaded liposomes for synergistic therapy of pancreatic cancer

Pancreatic cancer is predicted to be the second highest cause of cancer deaths by 2030, with a mortality rate of 98 % and a 5-year survival rate of only 4-8 %. FOLFIRINOX which consists of four main ingredients has shown superior efficacy in treating patients with pancreatic cancer compared to other agents and combinations. However, toxicities have prevented full-dose use of FOLFIRINOX. In this study, we present the design of a liposome nanosystem that enables the sequential release of a drug combination that is called FOLFIRINOX using lipid-based nanosystem synergistic chemo/photothermal therapy approaches. The co-eccentric liposome allowed us to locate the drug molecules in different locations giving us the flexibility to release them in a selected order. Core liposome (L2) has a melting temperature of 53.63 °C, it was decorated by gold nanoparticle (L2@AuNP) to bring photothermal responsiveness. The outer liposome structure had a lower melting temperature, which facilitated the sequential release process. The efficacy of photothermal therapy for nanosystem was calculated. The results indicate that coating L2@AuNP nanostructure with L1 liposomes improves efficacy by stabilizing gold nanoparticles. FOLFIRINOX components are encapsulated in a concentric liposome structure according to the order of administration into the body. The concentric liposome structure enables the sequential release of multiple drugs due to the varying phase transition temperatures of the liposomes. The cytotoxic effect of these formulations was evaluated on Panc-1 pancreatic cancer cells; the lowest cell viability was obtained in 4 Liposome(L) under 5 min NIR irradiation. Combination therapy has a higher therapeutic efficacy (70.45 %) when compared to chemotherapy and photothermal therapy used separately. The study's results show the potential of combination therapies to improve therapeutic outcomes, providing a promising path for future research and clinical application.

Advancements in Betulinic Acid-Loaded Nanoformulations for Enhanced Anti-Tumor Therapy

Betulinic acid (BA) is a natural compound obtained from plant extracts and is known for its diverse pharmacological effects, including anti-tumor, antibacterial, anti-inflammatory, antiviral, and anti-atherosclerotic properties. Its potential in anti-tumor therapy has garnered considerable attention, particularly for the treatment of breast, lung, and liver cancers. However, the clinical utility of BA is greatly hindered by its poor water solubility, low bioavailability, and off-target toxicity. To address these issues, researchers have developed various BA-loaded nanoformulations, such as nanoparticles, liposomes, micelles, and nanofibers, aiming to improve its solubility and bioavailability, prolong plasma half-life, and enhance targeting ability, thereby augmenting its anti-cancer efficacy. In preparing this review, we conducted extensive searches in well-known databases, including PubMed, Web of Science, and ScienceDirect, using keywords like "betulinic acid", "nanoparticles", "drug delivery", "tumor", and "cancer", covering the literature from 2014 to 2024. The review provides a comprehensive overview of recent advancements in the application of BA-loaded nano-delivery systems for anti-tumor therapy and offers insights into their future development prospects.

Photothermal therapy of xenografted tumor by carbon nanoparticles-Fe(II) complex

Due to the unique structure, carbon nanomaterials could convert near-infrared (NIR) light into heat efficiently in tumor ablation using photothermal therapy (PTT). However, none of them has been applied in clinical treatment, because they have not been approved for clinical evaluations and the precise temperature control facility is scarce. In this study, we designed a temperature-responsive controller for PTT and used carbon nanoparticles-Fe(II) complex (CNSI-Fe) as photothermal conversion agent (PTA) for PTT of tumor in vitro and in vivo. CNSI-Fe was an innovative drug under the evaluations in clinical trials. CNSI-Fe showed excellent photothermal conversion ability in water to increase the water temperature by 40 °C within 5 min under irradiation of 808 nm laser at 0.5 W/cm2. The temperature was precisely controlled at 52 °C for both in vitro and in vivo tumor inhibition. CNSI-Fe with NIR irradiation showed higher tumor cell inhibition than CNSI. In tumor bearing mice, CNSI-Fe with NIR irradiation achieved an inhibition rate of 84.7 % and 71.4 % of them were completely cured. Mechanistically, CNSI-Fe under NIR irradiation induced the radical generation, oxidative damage and ferroptosis to kill tumor. In addition, CNSI-Fe showed good biosafety during PTT according to hematological, serum biological and histopathological examinations. These results indicated that the combination of chemotherapy and PTT provided higher antitumor efficiency using CNSI-Fe as PTA.

Drug Delivery Systems of Betulin and Its Derivatives: An Overview

Natural origin products are regarded as promising for the development of new therapeutic therapies with improved effectiveness, biocompatibility, reduced side effects, and low cost of production. Betulin (BE) is very promising due to its wide range of pharmacological activities, including its anticancer, antioxidant, and antimicrobial properties. However, despite advancements in the use of triterpenes for clinical purposes, there are still some obstacles that hinder their full potential, such as their hydrophobicity, low solubility, and poor bioavailability. To address these concerns, new BE derivatives have been synthesized. Moreover, drug delivery systems have emerged as a promising solution to overcome the barriers faced in the clinical application of natural products. The aim of this manuscript is to summarize the recent achievements in the field of delivery systems of BE and its derivatives. This review also presents the BE derivatives mostly considered for medical applications. The electronic databases of scientific publications were searched for the most interesting achievements in the last ten years. Thus far, it is mostly nanoparticles (NPs) that have been considered for the delivery of betulin and its derivatives, including organic NPs (e.g., micelles, conjugates, liposomes, cyclodextrins, protein NPs), inorganic NPs (carbon nanotubes, gold NPs, silver), and complex/hybrid and miscellaneous nanoparticulate systems. However, there are also examples of microparticles, gel-based systems, suspensions, emulsions, and scaffolds, which seem promising for the delivery of BE and its derivatives.

Targeted Liposomal Drug Delivery: Overview of the Current Applications and Challenges

In drug development, it is not uncommon that an active substance exhibits efficacy in vitro but lacks the ability to specifically reach its target in vivo. As a result, targeted drug delivery has become a primary focus in the pharmaceutical sciences. Since the approval of Doxil® in 1995, liposomes have emerged as a leading nanoparticle in targeted drug delivery. Their low immunogenicity, high versatility, and well-documented efficacy have led to their clinical use against a wide variety of diseases. That being said, every disease is accompanied by a unique set of physiological conditions, and each liposomal product must be formulated with this consideration. There are a multitude of different targeting techniques for liposomes that can be employed depending on the application. Passive techniques such as PEGylation or the enhanced permeation and retention effect can improve general pharmacokinetics, while active techniques such as conjugating targeting molecules to the liposome surface may bring even further specificity. This review aims to summarize the current strategies for targeted liposomes in the treatment of diseases.

Multifunctional nanoparticles for the treatment and diagnosis of osteosarcoma

Osteosarcoma (OS) is a common primary malignant bone tumor in adolescents. Currently, the commonly used treatment strategies for OS include surgery, chemotherapy and radiotherapy. However, these methods have some problems that cannot be ignored, such as postoperative sequelae and severe side effects. Therefore, in recent years, researchers have been looking for other means to improve the treatment or diagnosis effect of OS and increase the overall survival rate of patients. With the development of nanotechnology, nanoparticles (NPs) have presented excellent properties in improving the therapeutic efficacy of drugs for OS. Nanotechnology makes it possible for NPs to combine various functional molecules and drugs to achieve multiple therapeutic effects. This review presents the important properties of multifunctional NPs for the treatment and diagnosis of OS and focuses on the research progress of common NPs applied for drug or gene delivery, phototherapy and diagnosis of OS, such as carbon-based quantum dots, metal, chitosan and liposome NPs. Finally, the promising prospects and challenges of developing multifunctional NPs with enhanced efficacy are discussed, which lays the foundation and direction for improving the future therapeutic and diagnostic methods of OS.

Cisplatin-loaded gold nanoshells mediate chemo-photothermal therapy against primary and distal lung cancers growth

Lung cancer is the most common cause of cancer mortality worldwide. The advances in surgery, radiotherapy, chemotherapeutic and immunotherapeutic drugs have progressed in the past decades, but the prognosis of lung cancer is still poor. In this study, we developed cisplatin (CDDP)-loaded human serum albumin (HSA)-based gold nanoshells (HCP@GNSs) for synergistic chemo-photothermal therapy (chemo-PTT). The HCP@GNSs not only acted as drug nanocarriers for chemotherapy but also serve as a superior mediator for PTT, which could exhibit a temperature increase upon a near infrared (NIR) laser exposure that was sufficient for photothermal ablation. HCP@GNSs were highly biocompatible and hemocompatible nanocarriers, while the synergistic chemo-PTT resulting from HCP@GNSs plus NIR exposure displayed stronger cytotoxicity effect than HCP@GNSs or PTT alone, especially at a low CDDP concentration. In vivo analysis demonstrated that HCP@GNSs-mediated chemo-PTT increased necrosis in tumors to achieve a high tumor clearance rate with no adverse side effects. Moreover, HCP@GNSs-medicated chemo-PTT induced the recruitment of dendritic cells, B-cells, and natural killer T-cells in distal tumors to inhibit the growth of the tumors. Therefore, the CDDP-loaded HCP@GNSs may be a potential nanomedicine candidate for curative lung cancer treatment in the future.

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.

Gold-Nanoparticle Hybrid Nanostructures for Multimodal Cancer Therapy

With the urgent need for bio-nanomaterials to improve the currently available cancer treatments, gold nanoparticle (GNP) hybrid nanostructures are rapidly rising as promising multimodal candidates for cancer therapy. Gold nanoparticles (GNPs) have been hybridized with several nanocarriers, including liposomes and polymers, to achieve chemotherapy, photothermal therapy, radiotherapy, and imaging using a single composite. The GNP nanohybrids used for targeted chemotherapy can be designed to respond to external stimuli such as heat or internal stimuli such as intratumoral pH. Despite their promise for multimodal cancer therapy, there are currently no reviews summarizing the current status of GNP nanohybrid use for cancer theragnostics. Therefore, this review fulfills this gap in the literature by providing a critical analysis of the data available on the use of GNP nanohybrids for cancer treatment with a specific focus on synergistic approaches (i.e., triggered drug release, photothermal therapy, and radiotherapy). It also highlights some of the challenges that hinder the clinical translation of GNP hybrid nanostructures from bench to bedside. Future studies that could expedite the clinical progress of GNPs, as well as the future possibility of improving GNP nanohybrids for cancer theragnostics, are also summarized.

Updates on Responsive Drug Delivery Based on Liposome Vehicles for Cancer Treatment

Liposomes are well-known nanoparticles with a non-toxic nature and the ability to incorporate both hydrophilic and hydrophobic drugs simultaneously. As modern drug delivery formulations are produced by emerging technologies, numerous advantages of liposomal drug delivery systems over conventional liposomes or free drug treatment of cancer have been reported. Recently, liposome nanocarriers have exhibited high drug loading capacity, drug protection, improved bioavailability, enhanced intercellular delivery, and better therapeutic effect because of resounding success in targeting delivery. The site targeting of smart responsive liposomes, achieved through changes in their physicochemical and morphological properties, allows for the controlled release of active compounds under certain endogenous or exogenous stimuli. In that way, the multifunctional and stimuli-responsive nanocarriers for the drug delivery of cancer therapeutics enhance the efficacy of treatment prevention and fighting over metastases, while limiting the systemic side effects on healthy tissues and organs. Since liposomes constitute promising nanocarriers for site-targeted and controlled anticancer drug release, this review focuses on the recent progress of smart liposome achievements for anticancer drug delivery applications.

Progress of phototherapy for osteosarcoma and application prospect of blue light photobiomodulation therapy

Osteosarcoma (OS) is the most common primary malignant bone tumor that mainly affects the pediatric and adolescent population; limb salvage treatment has become one of the most concerned and expected outcomes of OS patients recently. Phototherapy (PT), as a novel, non-invasive, and efficient antitumor therapeutic approach including photodynamic therapy (PDT), photothermal therapy (PTT), and photobiomodulation therapy (PBMT), has been widely applied in superficial skin tumor research and clinical treatment. OS is the typical deep tumor, and its phototherapy research faces great limitations and challenges. Surprisingly, pulse mode LED light can effectively improve tissue penetration and reduce skin damage caused by high light intensity and has great application potential in deep tumor research. In this review, we discussed the research progress and related molecular mechanisms of phototherapy in the treatment of OS, mainly summarized the status quo of blue light PBMT in the scientific research and clinical applications of tumor treatment, and outlooked the application prospect of pulsed blue LED light in the treatment of OS, so as to further improve clinical survival rate and prognosis of OS treatment and explore corresponding cellular mechanisms.

Theoretical and in vivo experimental investigation of laser hyperthermia for vascular dermatology mediated by liposome@Au core-shell nanoparticles

The 1064 nm Nd:YAG laser shows a good prospect for the treatment of port-wine stain (PWS), but it is necessary to enhance the blood absorption to laser energy by exogenous chromophore. Owing to the conjunction effect of local surface plasmon resonance (LSPR) by gold nanoparticle and drug delivery as well as lumen blockage abilities by liposome, liposome@Au core-shell nanoparticles are used as exogenous chromophore, and the efficiency of photothermal therapy is studied systematically. In this work, theoretical simulations were conducted to investigate the electric field and solid heat conduction of liposome@Au core-shell nanoparticles with various size and particles distance, aiming to achieve maximum photothermal conversion efficiency during the laser irradiation. Thereafter, liposome@Au core-shell nanoparticles with optimal size and structure were prepared, and in vivo experiments were conducted to evaluate the thermal damage of blood vessels enhanced by liposome@Au core-shell nanoparticles. Theoretical results imply that maximum temperature rise (167 K) is obtained when radius is 45 nm and shell thickness is 5 nm with distance of 4 nm. Liposome@Au core-shell nanoparticles were prepared with diameter of 101 nm and shell thickness of 5 nm according to the finite element simulation of electric field and solid heat conduction. When the molar ratio of chloroauric acid to phospholipid is 2.25, the LSPR absorption peak is about 981 nm, which is close to the wavelength of Nd:YAG laser. In vivo experiments show that injecting liposome@Au core-shell nanoparticles into the blood vessels can effectively reduce the number of laser pulses and the corresponding energy density required for obvious vasoconstriction.

A dual-responsive "Yin-Yang" photothermal delivery system to accelerate Parthenolide anti-tumor efficacy

Parthenolide (PTL), a germacrane sesquiterpene lactone extracted from the "Yin" Chinese traditional herb feverfew, has gained interest due to its lethal effects on tumor cells and its pharmacological effects within traditional Chinese medicine theory. To overcome low, non-targeted accumulation and uncontrolled release of PTL administration, a dual-responsive PTL-liposomes@chitosan@gold nanoshells (PTL-Lips@CS@GNS) system was fabricated. Hyperthermia generated under light irradiation in the near-infrared region via local surface plasmon resonance of gold nanoshells induced photothermal therapy, which also stimulated PTL release due to the liposomes gel-to-liquid crystalline phase transition. Additionally, PTL-Lips@CS@GNS exhibited a pH-responsive release in the acidic tumor microenvironment. Collectively, this study provides a realistic strategy for an effective combination of traditional Chinese medicine and current nanotechnology for tumor therapy.

Functionalized Nanostructured Bioactive Carriers: Nanoliposomes, Quantum Dots, Tocosome and Theranostic Approach

BACKGROUND

Lipidic nanocarriers have great potential for the encapsulation and delivery of numerous bioactive compounds. They have demonstrated significant benefits over traditional disease management and conventional therapy. The benefits associated with the particular properties of lipidic nanocarriers include site-specific drug deposition, improved pharmacokinetics and pharmacodynamics, enhanced internalization and intracellular transport, biodegradability, and decreased biodistribution. These properties result in the alleviation of the harmful consequences of conventional treatment protocols. Scope and approach: The administration of various bioactive molecules has been extensively investigated using nanostructured lipid carriers. In this article, theranostic applications of novel formulations of lipidic nanocarriers combined or complexed with quantum dots, certain polymers such as chitosan, and metallic nanoparticles (particularly gold) are reviewed. These formulations have demonstrated better controlled release features, improved drug loading capability, as well as a lower burst release rate. As a recent innovation in the field of drug delivery, tocosomes and their unique advantages are also explained in the final section of this entry.

KEY FINDINGS AND CONCLUSIONS

Theranostic medicine requires nanocarriers with improved target-specific accumulation and bio-distribution. Towards this end, lipid-based nanocarrier systems and tocosomes combined with unique properties of quantum dots, biocompatible polymers, and metallic nanoparticles seem to be ideal candidates to be considered for safe and efficient drug delivery.

The Optimized Delivery of Triterpenes by Liposomal Nanoformulations: Overcoming the Challenges

The last decade has witnessed a sustained increase in the research development of modern-day chemo-therapeutics, especially for those used for high mortality rate pathologies. However, the therapeutic landscape is continuously changing as a result of the currently existing toxic side effects induced by a substantial range of drug classes. One growing research direction driven to mitigate such inconveniences has converged towards the study of natural molecules for their promising therapeutic potential. Triterpenes are one such class of compounds, intensively investigated for their therapeutic versatility. Although the pharmacological effects reported for several representatives of this class has come as a well-deserved encouragement, the pharmacokinetic profile of these molecules has turned out to be an unwelcomed disappointment. Nevertheless, the light at the end of the tunnel arrived with the development of nanotechnology, more specifically, the use of liposomes as drug delivery systems. Liposomes are easily synthesizable phospholipid-based vesicles, with highly tunable surfaces, that have the ability to transport both hydrophilic and lipophilic structures ensuring superior drug bioavailability at the action site as well as an increased selectivity. This study aims to report the results related to the development of different types of liposomes, used as targeted vectors for the delivery of various triterpenes of high pharmacological interest.

Delivery of siRNA Using Functionalized Gold Nanorods Enhances Anti-Osteosarcoma Efficacy

Gold nanorods (GNRs) are intensively explored for the application in cancer therapy, which has motivated the development of photothermal therapy (PTT) multifunctional nanoplatforms based on GNRs to cure osteosarcoma (OS). However, the major limitations include the toxicity of surface protectants of GNRs, unsatisfactory targeting therapy, and the resistant effects of photothermal-induced autophagy, so the risk of relapse and metastasis of OS increase. In the present study, the GNR multifunctional nanoplatforms were designed and synthesized to deliver transcription factor EB (TFEB)-siRNA-targeting autophagy; then, the resistance of autophagy to PTT and the pH-sensitive cell-penetrating membrane peptide (CPP) was weakened, which could improve the tumor-targeting ability of the GNR nanoplatforms and realize an efficient synergistic effect for tumor treatment. Meanwhile, it is worth noting that the GNR nanoplatform groups have anti-lung metastasis of OS. This study provides a new reference to improve the efficacy of OS clinically.

The synergistic effect of chemo-photothermal therapies in SN-38-loaded gold-nanoshell-based colorectal cancer treatment

Aim: 7-Ethyl-10-hydroxycamptothecin (SN-38)-loaded gold nanoshells nanoparticles (HSP@Au NPs) were developed for combined chemo-photothermal therapy to treat colorectal cancer. Materials & methods: SN-38-loaded nanoparticles (HSP NPs) were prepared by the lyophilization-hydration method, and then developed into gold nanoshells. The nanoparticles were characterized and assessed for photothermal properties, cytotoxicity and hemocompatibility in vitro. In vivo anticancer activity was tested in a tumor mouse model. Results: The HSP@Au NPs (diameter 186.9 nm, zeta potential 33.4 mV) led to significant cytotoxicity in cancer cells exposed to a near-infrared laser. Moreover, the HSP@Au NP-mediated chemo-photothermal therapy displayed significant tumor growth suppression and disappearance (25% of tumor clearance rate) without adverse side effects in vivo. Conclusion: HSP@Au NPs may be promising in the treatment of colorectal cancer in the future.

Design and Application of Near-Infrared Nanomaterial-Liposome Hybrid Nanocarriers for Cancer Photothermal Therapy

Liposomes are attractive carriers for targeted and controlled drug delivery receiving increasing attention in cancer photothermal therapy. However, the field of creating near-infrared nanomaterial-liposome hybrid nanocarriers (NIRN-Lips) is relatively little understood. The hybrid nanocarriers combine the dual superiority of nanomaterials and liposomes, with more stable particles, enhanced photoluminescence, higher tumor permeability, better tumor-targeted drug delivery, stimulus-responsive drug release, and thus exhibiting better anti-tumor efficacy. Herein, this review covers the liposomes supported various types of near-infrared nanomaterials, including gold-based nanomaterials, carbon-based nanomaterials, and semiconductor quantum dots. Specifically, the NIRN-Lips are described in terms of their feature, synthesis, and drug-release mechanism. The design considerations of NIRN-Lips are highlighted. Further, we briefly introduced the photothermal conversion mechanism of NIRNs and the cell death mechanism induced by photothermal therapy. Subsequently, we provided a brief conclusion of NIRNs-Lips applied in cancer photothermal therapy. Finally, we discussed a synopsis of associated challenges and future perspectives for the applications of NIRN-Lips in cancer photothermal therapy.

Progress of Phototherapy Applications in the Treatment of Bone Cancer

Bone cancer including primary bone cancer and metastatic bone cancer, remains a challenge claiming millions of lives and affecting the life quality of survivors. Conventional treatments of bone cancer include wide surgical resection, radiotherapy, and chemotherapy. However, some bone cancer cells may remain or recur in the local area after resection, some are highly resistant to chemotherapy, and some are insensitive to radiotherapy. Phototherapy (PT) including photodynamic therapy (PDT) and photothermal therapy (PTT), is a clinically approved, minimally invasive, and highly selective treatment, and has been widely reported for cancer therapy. Under the irradiation of light of a specific wavelength, the photosensitizer (PS) in PDT can cause the increase of intracellular ROS and the photothermal agent (PTA) in PTT can induce photothermal conversion, leading to the tumoricidal effects. In this review, the progress of PT applications in the treatment of bone cancer has been outlined and summarized, and some envisioned challenges and future perspectives have been mentioned. This review provides the current state of the art regarding PDT and PTT in bone cancer and inspiration for future studies on PT.

Applications of Aptamer-Bound Nanomaterials in Cancer Therapy

Cancer is still a major disease that threatens human life. Although traditional cancer treatment methods are widely used, they still have many disadvantages. Aptamers, owing to their small size, low toxicity, good specificity, and excellent biocompatibility, have been widely applied in biomedical areas. Therefore, the combination of nanomaterials with aptamers offers a new method for cancer treatment. First, we briefly introduce the situation of cancer treatment and aptamers. Then, we discuss the application of aptamers in breast cancer treatment, lung cancer treatment, and other cancer treatment methods. Finally, perspectives on challenges and future applications of aptamers in cancer therapy are discussed.

Smart Stimuli-Responsive Liposomal Nanohybrid Systems: A Critical Review of Theranostic Behavior in Cancer

The epoch of nanotechnology has authorized novel investigation strategies in the area of drug delivery. Liposomes are attractive biomimetic nanocarriers characterized by their biocompatibility, high loading capacity, and their ability to reduce encapsulated drug toxicity. Nevertheless, various limitations including physical instability, lack of site specificity, and low targeting abilities have impeded the use of solo liposomes. Metal nanocarriers are emerging moieties that can enhance the therapeutic activity of many drugs with improved release and targeted potential, yet numerous barriers, such as colloidal instability, cellular toxicity, and poor cellular uptake, restrain their applicability in vivo. The empire of nanohybrid systems has shelled to overcome these curbs and to combine the criteria of liposomes and metal nanocarriers for successful theranostic delivery. Metallic moieties can be embedded or functionalized on the liposomal systems. The current review sheds light on different liposomal-metal nanohybrid systems that were designed as cellular bearers for therapeutic agents, delivering them to their targeted terminus to combat one of the most widely recognized diseases, cancer.

Hybrid Nanosystems for Biomedical Applications

Inorganic/organic hybrid nanosystems have been increasingly developed for their versatility and efficacy at overcoming obstacles not readily surmounted by nonhybridized counterparts. Currently, hybrid nanosystems are implemented for gene therapy, drug delivery, and phototherapy in addition to tissue regeneration, vaccines, antibacterials, biomolecule detection, imaging probes, and theranostics. Though diverse, these nanosystems can be classified according to foundational inorganic/organic components, accessory moieties, and architecture of hybridization. Within this Review, we begin by providing a historical context for the development of biomedical hybrid nanosystems before describing the properties, synthesis, and characterization of their component building blocks. Afterward, we introduce the architectures of hybridization and highlight recent biomedical nanosystem developments by area of application, emphasizing hybrids of distinctive utility and innovation. Finally, we draw attention to ongoing clinical trials before recapping our discussion of hybrid nanosystems and providing a perspective on the future of the field.

Thermosensitive Betulinic Acid-Loaded Magnetoliposomes: A Promising Antitumor Potential for Highly Aggressive Human Breast Adenocarcinoma Cells Under Hyperthermic Conditions

PURPOSE

Breast cancer presents one of the highest rates of prevalence around the world. Despite this, the current breast cancer therapy is characterized by significant side effects and high risk of recurrence. The present work aimed to develop a new therapeutic strategy that may improve the current breast cancer therapy by developing a heat-sensitive liposomal nano-platform suitable to incorporate both anti-tumor betulinic acid (BA) compound and magnetic iron nanoparticles (MIONPs), in order to address both remote drug release and hyperthermia-inducing features. To address the above-mentioned biomedical purposes, the nanocarrier must possess specific features such as specific phase transition temperature, diameter below 200 nm, superparamagnetic properties and heating capacity. Moreover, the anti-tumor activity of the developed nanocarrier should significantly affect human breast adenocarcinoma cells.

METHODS

BA-loaded magnetoliposomes and corresponding controls (BA-free liposomes and liposomes containing no magnetic payload) were obtained through the thin-layer hydration method. The quality and stability of the multifunctional platforms were physico-chemically analysed by the means of RAMAN, scanning electron microscopy-EDAX, dynamic light scattering, zeta potential and DSC analysis. Besides this, the magnetic characterization of magnetoliposomes was performed in terms of superparamagnetic behaviour and heating capacity. The biological profile of the platforms and controls was screened through multiple in vitro methods, such as MTT, LDH and scratch assays, together with immunofluorescence staining. In addition, CAM assay was performed in order to assess a possible anti-angiogenic activity induced by the test samples.

RESULTS

The physico-chemical analysis revealed that BA-loaded magnetoliposomes present suitable characteristics for the purpose of this study, showing biocompatible phase transition temperature, a diameter of 198 nm, superparamagnetic features and heating capacity. In vitro results showed that hyperthermia induces enhanced anti-tumor activity when breast adenocarcinoma MDA-MB-231 cells were exposed to BA-loaded magnetoliposomes, while a low cytotoxic rate was exhibited by the non-tumorigenic breast epithelial MCF 10A cells. Moreover, the in ovo angiogenesis assay endorsed the efficacy of this multifunctional platform as a good strategy for breast cancer therapy, under hyperthermal conditions. Regarding the possible mechanism of action of this multifunctional nano-platform, the immunocytochemistry of the MCF7 and MDA-MB-231 breast carcinoma cells revealed a microtubule assembly modulatory activity, under hyperthermal conditions.

CONCLUSION

Collectively, these findings indicate that BA-loaded magnetoliposomes, under hyperthermal conditions, might serve as a promising strategy for breast adenocarcinoma treatment.

Nanomaterials for the Photothermal Killing of Bacteria

An upsurge in the multidrug-resistant (MDR) bacterial pestilence is a global cause for concern in terms of human health. Lately, nanomaterials with photothermal effects have assisted in the efficient killing of MDR bacteria, attributable to their uncommon plasmonic, photocatalytic, and structural properties. Examinations of substantial amounts of photothermally enabled nanomaterials have shown bactericidal effects in an optimized time under near-infrared (NIR) light irradiation. In this review, we have compiled recent advances in photothermally enabled nanomaterials for antibacterial activities and their mechanisms. Photothermally enabled nanomaterials are classified into three groups, including metal-, carbon-, and polymer-based nanomaterials. Based on substantial accomplishments with photothermally enabled nanomaterials, we have inferred current trends and their prospective clinical applications.

Seedless synthetic branched gold nanoshells for chemo-thermal antitumor therapy

Gold nanomaterials (GNMs) are used in photothermal therapy due to their superior optical properties and excellent biocompatibility. However, the complex preparation process involving seed-mediated growth limits further clinical applications of GNMs. Herein, a novel one-pot approach to rapidly prepare liposome-based branched gold nanoshells (BGNS) as an antitumor drug nanocarrier is reported. This efficient seedless synthesis realized tunable absorption peaks of BGNS through controlling the concentration of the Au precursor solution, obtaining high absorbance in the near-infrared (NIR) window to achieve a superior photothermal effect. Hyperthermia during NIR laser irradiation can ablate the tumor and trigger drug release to achieve combined treatment. After laser irradiation, the nanocarriers disintegrated into individual gold nanoparticles (size: about 8 nm), which can be metabolized by the kidneys. Cell experiments in vitro and experiments involving mice with tumors have confirmed that the nanodrugs have strong antitumor effects. Such a flexible method provides a universal approach for rapidly preparing liposome-based gold nanoshells, which have the potential for large-scale preparation for further clinical applications.

Lipid-coated ZnO nanoparticles synthesis, characterization and cytotoxicity studies in cancer cell

ZnO nanoparticles are widely used in biological, chemical, and medical fields, but their toxicity impedes their wide application. In this study, pristine ZnO NPs (~ 7 nm; ~ 18 nm; ~ 49 nm) and lipid-coated ZnO NPs (~ 13 nm; ~ 22 nm; ~ 52 nm) with different morphologies were prepared by chemical method and characterized by TEM, XRD, HRTEM, FTIR, and DLS. Our results showed that the lipid-coated ZnO NPs (~ 13 nm; ~ 22 nm; ~ 52 nm) groups improved the colloidal stability, prevented the aggregation and dissolution of nanocrystal particles in the solution, inhibited the dissolution of ZnO NPs into Zn²⁺ cations, and reduced cytotoxicity more efficiently than the pristine ZnO NPs (~ 7 nm; ~ 18 nm; ~ 49 nm). Compared to the lipid-coated ZnO NPs, pristine ZnO NPs (~ 7 nm; ~ 18 nm; ~ 49 nm) could dose-dependently destroy the cells at low concentrations. At the same concentration, ZnO NPs (~ 7 nm) exhibited the highest cytotoxicity. These results could provide a basis for the toxicological study of the nanoparticles and direct future investigations for preventing strong aggregation, reducing the toxic effects of lipid-bilayer and promoting the uptake of nanoparticles by HeLa cells efficiently.

Nanomagnetic liposome-encapsulated parthenolide and indocyanine green for targeting and chemo-photothermal antitumor therapy

Aim: To synthesize a drug-delivery system with chemo-photothermal function and magnetic targeting, to validate its antitumor effect. Materials & methods: Parthenolide (PTL), employing chemotherapy and indocyanine green (ICG) providing phototherapy, were encased separately in the lipid and aqueous phases of liposomes (Lips). The Fe₃O₄ nanoparticles (MNPs), endowing magnetic targeting, were modified on the surface of Lips. The antitumor effects were investigated in vitro and in vivo. Results: ICG-PTL-Lips@MNPs showed outstanding synergistic antitumor efficacy in vitro and in vivo. Especially, after 14-day treatment, the tumor volumes decreased significantly and the biotoxicity was very low. Conclusion: The designed ICG-PTL-Lips@MNPs possess synergistic effects of chemotherapy, photothermal and targeting therapy, which are expected to provide an alternative way to further improve antitumor efficacy.

Engineered Gold Nanoshells Killing Tumor Cells: New Perspectives

The current strategies to treat different kinds of cancer are mainly based on chemotherapy, surgery and radiation therapy. Unfortunately, these approaches are not specific and rather invasive as well. In this scenario, metal nano-shells, in particular gold-based nanoshells, offer interesting perspectives in the effort to counteract tumor cells, due to their unique ability to tune Surface Plasmon Resonance in different light-absorbing ranges. In particular, the Visible and Near Infrared Regions of the electromagnetic spectrum are able to penetrate through tissues. In this way, the light absorbed by the gold nanoshell at a specific wavelength is converted into heat, inducing photothermal ablation in treated cancer cells. Furthermore, inert gold shells can be easily functionalized with different types of molecules in order to bind cellular targets in a selective manner. This review summarizes the current state-of-art of nanosystems embodying gold shells, regarding methods of synthesis, bio-conjugations, bio-distribution, imaging and photothermal effects (in vitro and in vivo), providing new insights for the development of multifunctional antitumor drugs.

Overview of the application of inorganic nanomaterials in cancer photothermal therapy

Cancer photothermal therapy (PTT) has captured the attention of researchers worldwide due to its localized and trigger-activated therapeutic effect.

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.

Liposome Delivery of Natural STAT3 Inhibitors for the Treatment of Cancer

In the tumor microenvironment, cytokines, growth factors, and oncogenes mediate constitutive activation of the signal transducer and activator of transcription 3 (STAT3) signaling pathway in both cancer cells and infiltrating immune cells. STAT3 activation in cancer cells drives tumorigenic changes that allow for increased survival, proliferation, and resistance to apoptosis. The modulation of immune cells is more complicated and conflicting. STAT3 signaling drives the myeloid cell phenotype towards an immune suppressive state, which mediates T cell inhibition. On the other hand, STAT3 signaling in T cells leads to proliferation and T cell activity required for an anti-tumor response. Targeted delivery of STAT3 inhibitors to cancer cells and myeloid cells could therefore improve therapeutic outcomes. Many compounds that inhibit the STAT3 pathways for cancer treatment include peptide drugs, small molecule inhibitors, and natural compounds. However, natural compounds that inhibit STAT3 are often hydrophobic, which reduces their bioavailability and leads to unfavorable pharmacokinetics. This review focuses specifically on liposome-encapsulated natural STAT3 inhibitors and their ability to target cancer cells and myeloid cells to reduce tumor growth and decrease STAT3-mediated immune suppression. Many of these liposome formulations have led to profound tumor reduction and examples of combination formulations have been shown to eliminate tumors through immune modulation.

NIR Light-Degradable Antimony Nanoparticle-Based Drug-Delivery Nanosystem for Synergistic Chemo-Photothermal Therapy in Vitro

A novel drug-delivery nanosystem based on near-infrared (NIR) light-degradable antimony nanoparticles (AMNP) have been developed for synergistic chemo-phototherapy in vitro. The monodispersed AMNP were synthesized by using a simple and cost-effective method. Positively charged doxorubicin hydrochloride (DOX) was loaded onto the negatively charged surface of AMNP via electrostatic interaction and finally modified by polyacrylic acid (PAA) to enhance biocompatibility. Under NIR (808 nm) laser irradiation of the AMNP-DOX-PAA nanosystem, not only was high photothermal conversion efficiency of AMNP achieved but also pH-dependent DOX release was enhanced due to laser-induced hyperthermia. As a consequence, almost all of the HeLa cells (around 97%) were killed because of the combined effects of chemotherapy and photothermal therapy. More interestingly, AMNP showed very fast (about 10 min) laser-induced degradation that may help to minimize long-term toxicity after therapy by using same-wavelength NIR laser irradiation (808 nm). Computational total energy calculations and molecular dynamics simulations based on density functional theory (DFT) suggest that the NIR laser irradiation induces a photothermally activated reaction on the surface of AMNP in water, which can lead to surface degradation via the formation of Sb-H bonds first and then Sb-OH bonds upon further increase of temperature. This work demonstrates a simple platform that has potential applications for synergistic and highly effective chemo-photothermal therapy based on photodegradable nanoparticles.

Gold nanomaterials as key suppliers in biological and chemical sensing, catalysis, and medicine

BACKGROUND

Gold nanoparticles (AuNPs) with unique physicochemical properties have received a great deal of interest in the field of biological, chemical and biomedical implementations. Despite the widespread use of AuNPs in chemical and biological sensing, catalysis, imaging and diagnosis, and more recently in therapy, no comprehensive summary has been provided to explain how AuNPs could aid in developing improved sensing and catalysts systems as well as medical settings.

SCOPE OF REVIEW

The chemistry of Au-based nanosystems was followed by reviewing different applications of Au nanomaterials in biological and chemical sensing, catalysis, imaging and diagnosis by a number of approaches, and finally synergistic combination therapy of different cancers. Afterwards, the clinical impacts of AuNPs, future application of AuNPs, and opportunities and challenges of AuNPs application were also discussed.

MAJOR CONCLUSIONS

AuNPs show exclusive colloidal stability and are considered as ideal candidates for colorimetric detection, catalysis, imaging, and photothermal transducers, because their physicochemical properties can be tuned by adjusting their structural dimensions achieved by the different manufacturing methods.

GENERAL SIGNIFICANCE

This review provides some details about using AuNPs in sensing and catalysis applications as well as promising theranostic nanoplatforms for cancer imaging and diagnosis, and sensitive, non-invasive, and synergistic methods for cancer treatment in an almost comprehensive manner.

Thiol chitosan-wrapped gold nanoshells for near-infrared laser-induced photothermal destruction of antibiotic-resistant bacteria

Developing new antibacterial nanomaterials and novel therapeutic strategies for the destruction of human pathogenic bacteria that cause infectious diseases is becoming more crucial, because infections caused by antibiotic-resistant bacteria are becoming more and more difficult to be effectively cured with commercially available antibiotics. In this study, we successfully developed new thiol chitosan-wrapped gold nanoshells (TC-AuNSs) as an antibacterial agent for the near-infrared (NIR) laser-triggered photothermal destruction of antibiotic-resistant pathogens, such as Gram-positive bacteria (Staphylococcus aureus) and Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli), owing to their high water solubility, biocompatibility, strong NIR absorption, and outstanding photothermal properties. More interestingly, TC-AuNSs (115 μg/mL) were capable of completely destroying S. aureus, P. aeruginosa, and E.coli within 5 min of NIR laser irradiation, and no bacterial growth was detected on the tryptic soy agar (TSA) plate after 48 h of laser irradiation, indicating that TC-AuNSs along with laser irradiation are highly efficient and can kill bacteria quickly and prevent bacterial regrowth. We believe that TC-AuNSs deserve much more attention as an antibacterial agent, to be used in effectively combating pathogenic bacteria associated with public health problems and monitoring of environmental pollution for hygiene and safety.

Enhanced cancer therapy with pH-dependent and aptamer functionalized doxorubicin loaded polymeric (poly D, L-lactic-co-glycolic acid) nanoparticles

Aptamer based drug delivery systems are gaining the importance in anticancer therapy due to their targeted drug delivery efficiency without harming the normal cells. The present work formulated the pH-dependent aptamer functionalized polymer-based drug delivery system against human lung cancer. The prepared aptamer functionalized doxorubicin (DOX) loaded poly (D, L-lactic-co-glycolic acid) (PLGA), poly (N-vinylpyrrolidone) (PVP) nanoparticles (APT-DOX-PLGA-PVP NPs) were spherical in shape with an average size of 87.168 nm. The crystallography and presence of the PLGA (poly (D, L-lactic-co-glycolic acid)) and DOX (doxorubicin) in APT-DOX-PLGA-PVP NPs were indicated by the X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), and ¹H and ¹³C nuclear magnetic resonance spectrometer (NMR). The pH-dependent aptamer AS1411 based drug release triggered the cancer cell death was evidenced by cytotoxicity assay, flow cytometry, and fluorescent microscopic imaging. In addition, the cellular uptake of the DOX was determined and the apoptosis-related signaling pathway in the A549 cells was studied by Western blot analysis. Further, the in vivo study revealed that mice treated with APT-DOX-PLGA-PVP NPs were significantly recovered from cancer as evident by mice weight and tumor size followed by the histopathological study. It was reported that the APT-DOX-PLGA-PVP NPs induced the apoptosis through the activation of the apoptosis-related proteins. Hence, the present study revealed that the APT-DOX-PLGA-PVP NPs improved the therapeutic efficiency through the nucleolin receptor endocytosis targeted drug release.

In Search of Panacea-Review of Recent Studies Concerning Nature-Derived Anticancer Agents

Cancers are one of the leading causes of deaths affecting millions of people around the world, therefore they are currently a major public health problem. The treatment of cancer is based on surgical resection, radiotherapy, chemotherapy or immunotherapy, much of which is often insufficient and cause serious, burdensome and undesirable side effects. For many years, assorted secondary metabolites derived from plants have been used as antitumor agents. Recently, researchers have discovered a large number of new natural substances which can effectively interfere with cancer cells’ metabolism. The most famous groups of these compounds are topoisomerase and mitotic inhibitors. The aim of the latest research is to characterize natural compounds found in many common foods, especially by means of their abilities to regulate cell cycle, growth and differentiation, as well as epigenetic modulation. In this paper, we focus on a review of recent discoveries regarding nature-derived anticancer agents.

Betulin and its derivatives as novel compounds with different pharmacological effects

Betulin (B) and Betulinic acid (BA) are natural pentacyclic lupane-structure triterpenoids which possess a wide range of pharmacological activities. Recent evidence indicates that B and BA have several properties useful for the treatment of metabolic disorders, infectious diseases, cardiovascular disorders, and neurological disorders. In the current review, we discuss B and BA structures and derivatives and then comprehensively explain their pharmacological effects in relation to various diseases. We also explain antiviral, antibacterial and anti-cancer effects of B and BA. Finally, we discuss the delivery methods, in which these compounds most effectively target different systems.

Nano-drug System Based on Hierarchical Drug Release for Deep Localized/Systematic Cascade Tumor Therapy Stimulating Antitumor Immune Responses

Inaccessibility of deep-seated malignant cells in the central region of tumors and uncontrollable tumor recurrence represent a significant challenge for conventional synergistic cancer therapy. Herein, we designed a novel nanoplatform based on hierarchical drug release for deep cascade cancer therapy including localized photothermal therapy, systematic chemotherapy, and elicited immune responses. Methods: The first-step chemotherapy could be carried out by polydopamine (PDA) releasing doxorubicin (DOX) in the specific microenvironment of lysosomes (pH 5.5). The branched gold nanoshells and PDA converted the light to heat efficiently to accomplish the second-step photothermal therapy and collapsed biomimetic vesicles (BVs) to release paclitaxel (PTX), which promoted the third-step of chemotherapy and triggered immune responses. Results: After 10 days of treatment, there were no obvious residual tumors in tumor-bearing mice. Significantly, 10 days after stopping treatment, mice in the drug immune-therapeutic group showed little tumor recurrence (1.5 times) compared to substantial recurrence (20 times) in the conventional treatment group. Conclusion: The hierarchical drug release and cascade therapeutic modality enhance the penetration of drugs deep into the tumor tissue and effectively inhibit recurrence. This cascade therapeutic modality provides a novel approach for more effective cancer therapy.

A chemo-photothermal synergetic antitumor drug delivery system: Gold nanoshell coated wedelolactone liposome

In this study, an antitumor drug delivery system, gold nanoshell coated wedelolactone liposomes (AuNS-Wed-Lip), were designed and synthesized. In the drug delivery system, wedelolactone liposome and gold-nanoshell were linked by l-cysteine, which had been shown an effective nanocarrier for antitumor drug delivery, on-demand drug release, and phototherapy under near-infrared (NIR) light irradiation. It was capable of absorbing 780-850 nm NIR light and converting light energy to heat rapidly. The hyperthermia promoted wedelolactone release rapidly from the systems. The release amount of AuNS-Wed-Lip under NIR irradiation reached up to 97.34% over 8 h, achieving the on-demand drug release. Moreover, a high inhibition rate up to 95.73% for 143B tumor cells by AuNS-Wed-Lip upon laser irradiation at 808 nm was observed. The excellent inhibition efficacy was also displayed in vivo antitumor study with S180 tumor-bearing mice. The results demonstrated that AuNS-Wed-Lip, as an antitumor drug delivery system, achieved chemo-photothermal synergetic effect, which has great potential in cancer therapy.