Chlorins e6 loaded silica nanoparticles coated with gastric cancer cell membrane for tumor specific photodynamic therapy of gastric cancer

Recent advances in biomimetic cell membrane-camouflaged nanoparticles for cancer therapy

The emerging strategy of biomimetic nanoparticles (NPs) via cellular membrane camouflage holds great promise in cancer therapy. This scholarly review explores the utilization of cellular membranes derived from diverse cellular entities; blood cells, immune cells, cancer cells, stem cells, and bacterial cells as examples of NP coatings. The camouflaging strategy endows NPs with nuanced tumor-targeting abilities such as self-recognition, homotypic targeting, and long-lasting circulation, thus also improving tumor therapy efficacy overall. The comprehensive examination encompasses a variety of cell membrane camouflaged NPs (CMCNPs), elucidating their underlying targeted therapy mechanisms and delineating diverse strategies for anti-cancer applications. Furthermore, the review systematically presents the synthesis of source materials and methodologies employed in order to construct and characterize these CMCNPs, with a specific emphasis on their use in cancer treatment.

A Review: Surface Engineering of Lipid-Based Drug Delivery Systems

This review explores the evolution of lipid-based nanoparticles (LBNPs) for drug delivery (DD). Herein, LBNPs are classified into liposomes and cell membrane-based nanoparticles (CMNPs), each with unique advantages and challenges. Conventional LBNPs possess drawbacks such as poor targeting, quick clearance, and limited biocompatibility. One of the possible alternatives to overcome these challenges is surface modification of nanoparticles (NPs) with materials such as polyethylene glycol (PEG), aptamers, antibody fragments, peptides, CD44, hyaluronic acid, folic acid, palmitic acid, and lactoferrin. Thus, the main focus of this review will be on the different surface modifications that enable LBNPs to have beneficial properties for DD, such as enhancing mass transport properties, immune evasion, improved stability, and targeting. Moreover, various CMNPs are explored used for DD derived from cells such as red blood cells (RBCs), platelets, leukocytes, cancer cells, and stem cells, highlighting their unique natural properties (e.g., biocompatibility and ability to evade the immune system). This discussion extends to the biomimicking of hybrid NPs accomplished through the surface coating of synthetic (mainly polymeric) NPs with different cell membranes. This review aims to provide a comprehensive resource for researchers on recent advances in the field of surface modification of LBNPs and CMNPs. Overall, this review provides valuable insights into the dynamic field of lipid-based DD systems.

Current status, challenges and prospects of antifouling materials for oncology applications

Targeted therapy has become crucial to modern translational science, offering a remedy to conventional drug delivery challenges. Conventional drug delivery systems encountered challenges related to solubility, prolonged release, and inadequate drug penetration at the target region, such as a tumor. Several formulations, such as liposomes, polymers, and dendrimers, have been successful in advancing to clinical trials with the goal of improving the drug's pharmacokinetics and biodistribution. Various stealth coatings, including hydrophilic polymers such as PEG, chitosan, and polyacrylamides, can form a protective layer over nanoparticles, preventing aggregation, opsonization, and immune system detection. As a result, they are classified under the Generally Recognized as Safe (GRAS) category. Serum, a biological sample, has a complex composition. Non-specific adsorption of chemicals onto an electrode can lead to fouling, impacting the sensitivity and accuracy of focused diagnostics and therapies. Various anti-fouling materials and procedures have been developed to minimize the impact of fouling on specific diagnoses and therapies, leading to significant advancements in recent decades. This study provides a detailed analysis of current methodologies using surface modifications that leverage the antifouling properties of polymers, peptides, proteins, and cell membranes for advanced targeted diagnostics and therapy in cancer treatment. In conclusion, we examine the significant obstacles encountered by present technologies and the possible avenues for future study and development.

Targeted cancer treatment using folate-conjugated sponge-like ZIF-8 nanoparticles: a review

ZIF-8 (zeolitic imidazolate framework-8) is a potential drug delivery system because of its unique properties, which include a large surface area, a large pore capacity, a large loading capacity, and outstanding stability under physiological conditions. ZIF-8 nanoparticles may be readily functionalized with targeting ligands for the identification and absorption of particular cancer cells, enhancing the efficacy of chemotherapeutic medicines and reducing adverse effects. ZIF-8 is also pH-responsive, allowing medication release in the acidic milieu of cancer cells. Because of its tunable structure, it can be easily functionalized to design cancer-specific targeted medicines. The delivery of ZIF-8 to cancer cells can be facilitated by folic acid-conjugation. Hence, it can bind to overexpressed folate receptors on the surface of cancer cells, which holds the promise of reducing unwanted deliveries. As a result of its importance in cancer treatment, the folate-conjugated ZIF-8 was the major focus of this review.

Cancer Cell Membrane-Based Materials for Biomedical Applications

The nanodelivery system provides a novel direction for disease diagnosis and treatment; however, its delivery effectiveness is restricted by the short biological half-life and inadequate tumor targeting. The immune evasion properties and homologous targeting capabilities of natural cell membranes, particularly those of cancer cell membranes (CCM), have gained significant interest. The integration of CCM and nanoparticles has resulted in the emergence of CCM-based nanoplatforms (CCM-NPs), which have gained significant attention due to their unique properties. CCM-NPs not only prolong the blood circulation time of core nanoparticles, but also direct them for homologous tumor targeting. Herein, the history and development of CCM-NPs as well as how these platforms have been used for biomedical applications are discussed. The application of CCM-NPs for cancer therapy will be described in detail. Translational efforts are currently under way and further research to address key areas of need will ultimately be required to facilitate the successful clinical adoption of CCM-NPs.

Cell membrane-based biomimetic technology for cancer phototherapy: Mechanisms, recent advances and perspectives

Despite significant advances in medical technology and antitumour treatments, the diagnosis and treatment of tumours have undergone remarkable transformations. Noninvasive phototherapy methods, such as photodynamic therapy (PDT) and photothermal therapy (PTT), have gained significant interest in antitumour medicine. However, traditional photosensitisers or photothermal agents face challenges like immune system recognition, rapid clearance from the bloodstream, limited tumour accumulation, and phototoxicity concerns. Researchers combine photosensitisers or photothermal agents with natural cell membranes to overcome these obstacles to create a nano biomimetic therapeutic platform. When used to coat nanoparticles, red blood cells, platelets, cancer cells, macrophages, lymphocytes, and bacterial outer membranes could provide prolonged circulation, tumour targeting, immune stimulation, or antigenicity. This article covers the principles of cellular membrane biomimetic nanotechnology and phototherapy, along with recent advancements in applying nano biomimetic technology to PDT, PTT, PCT, and combined diagnosis and treatment. Furthermore, the challenges and issues of using nano biomimetic nanoparticles in phototherapy are discussed. STATEMENT OF SIGNIFICANCE: Currently, there has been significant progress in the field of cell membrane biomimetic technology. Researchers are exploring its potential application in tumor diagnosis and treatment through phototherapy. Scholars have conducted extensive research on combining cell membrane technology and phototherapy in anticancer diagnosis and treatment. This review aims to highlight the mechanisms of phototherapy and the latest advancements in single phototherapy (PTT, PDT) and combination phototherapy (PCT, PRT, and PIT), as well as diagnostic approaches. The review provides an overview of various cell membrane technologies, including RBC membranes, platelet membranes, macrophage cell membranes, tumour cell membranes, bacterial membranes, hybrid membranes, and their potential for anticancer applications under phototherapy. Lastly, the review discusses the challenges and future directions in this field.

Advances in Composite Biofilm Biomimetic Nanodrug Delivery Systems for Cancer Treatment

Single biofilm biomimetic nanodrug delivery systems based on single cell membranes, such as erythrocytes and cancer cells, have immune evasion ability, good biocompatibility, prolonged blood circulation, and high tumor targeting. Because of the different characteristics and functions of each single cell membrane, more researchers are using various hybrid cell membranes according to their specific needs. This review focuses on several different types of biomimetic nanodrug-delivery systems based on composite biofilms and looks forward to the challenges and possible development directions of biomimetic nanodrug-delivery systems based on composite biofilms to provide reference and ideas for future research.

Recent Innovations of Mesoporous Silica Nanoparticles Combined with Photodynamic Therapy for Improving Cancer Treatment

Cancer is a global health burden and is one of the leading causes of death. Photodynamic therapy (PDT) is considered an alternative approach to conventional cancer treatment. PDT utilizes a light-sensitive compound, photosensitizers (PSs), light irradiation, and molecular oxygen (O2). This generates cytotoxic reactive oxygen species (ROS), which can trigger necrosis and/ or apoptosis, leading to cancer cell death in the intended tissues. Classical photosensitizers impose limitations that hinder their clinical applications, such as long-term skin photosensitivity, hydrophobic nature, nonspecific targeting, and toxic cumulative effects. Thus, nanotechnology emerged as an unorthodox solution for improving the hydrophilicity and targeting efficiency of PSs. Among nanocarriers, mesoporous silica nanoparticles (MSNs) have gained increasing attention due to their high surface area, defined pore size and structure, ease of surface modification, stable aqueous dispersions, good biocompatibility, and optical transparency, which are vital for PDT. The advancement of integrated MSNs/PDT has led to an inspiring multimodal nanosystem for effectively treating malignancies. This review gives an overview of the main components and mechanisms of the PDT process, the effect of PDT on tumor cells, and the most recent studies that reported the benefits of incorporating PSs into silica nanoparticles and integration with PDT against different cancer cells.

Photodynamic Therapy: From the Basics to the Current Progress of N-Heterocyclic-Bearing Dyes as Effective Photosensitizers

Photodynamic therapy, an alternative that has gained weight and popularity compared to current conventional therapies in the treatment of cancer, is a minimally invasive therapeutic strategy that generally results from the simultaneous action of three factors: a molecule with high sensitivity to light, the photosensitizer, molecular oxygen in the triplet state, and light energy. There is much to be said about each of these three elements; however, the efficacy of the photosensitizer is the most determining factor for the success of this therapeutic modality. Porphyrins, chlorins, phthalocyanines, boron-dipyrromethenes, and cyanines are some of the N-heterocycle-bearing dyes' classes with high biological promise. In this review, a concise approach is taken to these and other families of potential photosensitizers and the molecular modifications that have recently appeared in the literature within the scope of their photodynamic application, as well as how these compounds and their formulations may eventually overcome the deficiencies of the molecules currently clinically used and revolutionize the therapies to eradicate or delay the growth of tumor cells.

Cell membrane-coated nanomaterials for cancer therapy

With the development of nanotechnology, nanoparticles have emerged as a delivery carrier for tumor drug therapy, which can improve the therapeutic effect by increasing the stability and solubility and prolonging the half-life of drugs. However, nanoparticles are foreign substances for humans, are easily cleared by the immune system, are less targeted to tumors, and may even be toxic to the body. As a natural biological material, cell membranes have unique biological properties, such as good biocompatibility, strong targeting ability, the ability to evade immune surveillance, and high drug-carrying capacity. In this article, we review cell membrane-coated nanoparticles (CMNPs) and their applications to tumor therapy. First, we briefly describe CMNP characteristics and applications. Second, we present the characteristics and advantages of different cell membranes as well as nanoparticles, provide a brief description of the process of CMNPs, discuss the current status of their application to tumor therapy, summarize their shortcomings for use in cancer therapy, and propose future research directions. This review summarizes the research progress on CMNPs in cancer therapy in recent years and assesses remaining problems, providing scholars with new ideas for future research on CMNPs in tumor therapy.

Cell membrane-coated nanoparticles: a novel multifunctional biomimetic drug delivery system

Recently, nanoparticle-based drug delivery systems have been widely used for the treatment, prevention, and detection of diseases. Improving the targeted delivery ability of nanoparticles has emerged as a critical issue that must be addressed as soon as possible. The bionic cell membrane coating technology has become a novel concept for the design of nanoparticles. The diverse biological roles of cell membrane surface proteins endow nanoparticles with several functions, such as immune escape, long circulation time, and targeted delivery; therefore, these proteins are being extensively studied in the fields of drug delivery, detoxification, and cancer treatment. Furthermore, hybrid cell membrane-coated nanoparticles enhance the beneficial effects of monotypic cell membranes, resulting in multifunctional and efficient delivery carriers. This review focuses on the synthesis, development, and application of the cell membrane coating technology and discusses the function and mechanism of monotypic/hybrid cell membrane-modified nanoparticles in detail. Moreover, it summarizes the applications of cell membranes from different sources and discusses the challenges that may be faced during the clinical application of bionic carriers, including their production, mechanism, and quality control. We hope this review will attract more scholars toward bionic cell membrane carriers and provide certain ideas and directions for solving the existing problems.

Chlorin e6: A Promising Photosensitizer in Photo-Based Cancer Nanomedicine

Conventional cancer treatment modalities are often associated with major therapeutic limitations and severe side effects. Photodynamic therapy is a localized noninvasive mode of treatment that has given a different direction to cancer research due to its effectivity against a wide range of cancers and minimal side effects. A photosensitizer is the key component of photodynamic therapy (PDT) that generates cytotoxic reactive oxygen species to eradicate cancer cells. As the therapeutic effectivity of PDT greatly depends upon the photosensitizer, great efforts have been made to search for an ideal photosensitizer. Chlorin e6 is a FDA approved second generation photosensitizer that meets the desired clinical properties for PDT. It is known for its high reactive oxygen species (ROS) generation ability and anticancer potency against many types of cancer. Hydrophobicity is a major drawback of Ce6 that leads to its poor biodistribution and rapid clearance from the circulatory system. To overcome this drawback, researchers have designed and fabricated several types of nanosystems, which can enhance Ce6 solubility and thereby enhance its bioavailability. These nanosystems also improve tumor accumulation of Ce6 by selectively targeting the cancer cells through passive and active targeting. In addition, Ce6 has been employed in many combination therapies like chemo-photodynamic therapy, photoimmunotherapy, and combined photodynamic-photothermal therapy. A combination therapy is more curative than a single therapy due to the synergistic effects of individual therapies. Ce6-based nanosystems for combination therapies have shown excellent results in various studies and provide a promising platform for cancer treatment.

Advances in cell membrane-coated nanoparticles and their applications for bone therapy

Due to the specific structure of natural bone, most of the therapeutics are incapable to be delivered into the targeted site with effective concentrations. Nanotechnology has provided a good way to improve this issue, cell membrane mimetic nanoparticles (NPs) have been emerging as an ideal nanomaterial which integrates the advantages of natural cell membranes with synthetic NPs to significantly improve the biocompatibility as well as achieving long-lasting circulation and targeted delivery. In addition, functionalized modifications of the cell membrane facilitate more precise targeting and therapy. Here, an overview of the preparation of cell membrane-coated NPs and the properties of cell membranes from different cell sources has been given to expatiate their function and potential applications. Strategies for functionalized modification of cell membranes are also briefly described. The application of cell membrane-coated NPs for bone therapy is then presented according to the function of cell membranes. Moreover, the prospects and challenges of cell membrane-coated NPs for translational medicine have also been discussed.

The "Light Knife" for Gastric Cancer: Photodynamic Therapy

Photodynamic therapy (PDT) has been used clinically to treat cancer for more than 40 years. Some solid tumors, including esophageal cancer, lung cancer, head and neck cancer, cholangiocarcinoma, and bladder cancer, have been approved for and managed with PDT in many countries globally. Notably, PDT for gastric cancer (GC) has been reported less and is not currently included in the clinical diagnosis and treatment guidelines. However, PDT is a potential new therapeutic modality used for the management of GC, and its outcomes and realization are more and more encouraging. PDT has a pernicious effect on tumors at the irradiation site and can play a role in rapid tumor shrinkage when GC is combined with cardiac and pyloric obstruction. Furthermore, because of its ability to activate the immune system, it still has a specific effect on systemic metastatic lesions, and the adverse reactions are mild. In this Review, we provide an overview of the current application progress of PDT for GC; systematically elaborate on its principle, mechanism, and the application of a new photosensitizer in GC; and focus on the efficacy of PDT in GC and the prospect of combined use with other therapeutic methods to provide a theoretical basis for clinical application.

Nanotherapeutic Intervention in Photodynamic Therapy for Cancer

The clinical need for photodynamic therapy (PDT) has been growing for several decades. Notably, PDT is often used in oncology to treat a variety of tumors since it is a low-risk therapy with excellent selectivity, does not conflict with other therapies, and may be repeated as necessary. The mechanism of action of PDT is the photoactivation of a particular photosensitizer (PS) in a tumor microenvironment in the presence of oxygen. During PDT, cancer cells produce singlet oxygen (¹O₂) and reactive oxygen species (ROS) upon activation of PSs by irradiation, which efficiently kills the tumor. However, PDT's effectiveness in curing a deep-seated malignancy is constrained by three key reasons: a tumor's inadequate PS accumulation in tumor tissues, a hypoxic core with low oxygen content in solid tumors, and limited depth of light penetration. PDTs are therefore restricted to the management of thin and superficial cancers. With the development of nanotechnology, PDT's ability to penetrate deep tumor tissues and exert desired therapeutic effects has become a reality. However, further advancement in this field of research is necessary to address the challenges with PDT and ameliorate the therapeutic outcome. This review presents an overview of PSs, the mechanism of loading of PSs, nanomedicine-based solutions for enhancing PDT, and their biological applications including chemodynamic therapy, chemo-photodynamic therapy, PDT-electroporation, photodynamic-photothermal (PDT-PTT) therapy, and PDT-immunotherapy. Furthermore, the review discusses the mechanism of ROS generation in PDT advantages and challenges of PSs in PDT.

Natural cell based biomimetic cellular transformers for targeted therapy of digestive system cancer

Digestive system cancer is the most common cause of cancer death in the world. Although cancer treatment options are increasingly diversified, the mortality rate of malignant cancer of the digestive system remains high. Therefore, it is necessary to explore effective cancer treatment methods. Recently, biomimetic nanoparticle delivery systems based on natural cells that organically integrate the low immunogenicity, high biocompatibility, cancer targeting, and controllable, versatile functionality of smart nanocarrier design with natural cells have been expected to break through the bottleneck of tumor targeted therapy. In this review, we focus on the dynamic changes and complex cellular communications that occur in vivo in natural cells based vehicles. Recent studies on the development of advanced targeted drug delivery systems using the dynamic behaviors such as specific surface protein affinity, morphological changes, and phenotypic polarization of natural cells are summarized. In addition to drug delivery mediated by dynamic behavior, functional “delivery” based on the natural cell themselves is also involved. Aiming to make the best use of the functions of cells, providing clues for the development of advanced drug delivery platforms.

New Advances in Nano-Drug Delivery Systems: Helicobacter pylori and Gastric Cancer

With the development of materials science and biomedicine, the application of nanomaterials in the medical field is further promoted. In the process of the diagnosis and treatment of diseases, a variety of drugs need to be used. It is an ideal state to make these drugs arrive at a specific location at a specific time and release at a specific speed, which can improve the bioavailability of drugs and reduce the adverse effects of drugs on normal tissues. Traditional drug delivery methods such as tablets, capsules, syrups, and ointments have certain limitations. The emergence of a new nano-drug delivery system further improves the accuracy of drug delivery and the efficacy of drugs. It is well known that the development of the cancer of the stomach is the most serious consequence for the infection of Helicobacter pylori. For the patients who are suffering from gastric cancer, the treatments are mainly surgery, chemotherapy, targeted and immune therapy, and other comprehensive treatments. Although great progress has been made, the diagnosis and prognosis of gastric cancer are still poor with patients usually diagnosed with cancer at an advanced stage. Current treatments are of limited benefits for patients, resulting in a poor 5-year survival rate. Nanomaterials may play a critical role in early diagnosis. A nano-drug delivery system can significantly improve the chemotherapy, targeted therapy, and immunotherapy of advanced gastric cancer, reduce the side effects of the original treatment plan and provide patients with better benefits. It is a promising treatment for gastric cancer. This article introduces the application of nanomaterials in the diagnosis and treatment of H. pylori and gastric cancer.

Heptamethine Cyanine-Loaded Nanomaterials for Cancer Immuno-Photothermal/Photodynamic Therapy: A Review

The development of strategies capable of eliminating metastasized cancer cells and preventing tumor recurrence is an exciting and extremely important area of research. In this regard, therapeutic approaches that explore the synergies between nanomaterial-mediated phototherapies and immunostimulants/immune checkpoint inhibitors have been yielding remarkable results in pre-clinical cancer models. These nanomaterials can accumulate in tumors and trigger, after irradiation of the primary tumor with near infrared light, a localized temperature increase and/or reactive oxygen species. These effects caused damage in cancer cells at the primary site and can also (i) relieve tumor hypoxia, (ii) release tumor-associated antigens and danger-associated molecular patterns, and (iii) induced a pro-inflammatory response. Such events will then synergize with the activity of immunostimulants and immune checkpoint inhibitors, paving the way for strong T cell responses against metastasized cancer cells and the creation of immune memory. Among the different nanomaterials aimed for cancer immuno-phototherapy, those incorporating near infrared-absorbing heptamethine cyanines (Indocyanine Green, IR775, IR780, IR797, IR820) have been showing promising results due to their multifunctionality, safety, and straightforward formulation. In this review, combined approaches based on phototherapies mediated by heptamethine cyanine-loaded nanomaterials and immunostimulants/immune checkpoint inhibitor actions are analyzed, focusing on their ability to modulate the action of the different immune system cells, eliminate metastasized cancer cells, and prevent tumor recurrence.

Synergistic photothermal-photodynamic-chemotherapy toward breast cancer based on a liposome-coated core-shell AuNS@NMOFs nanocomposite encapsulated with gambogic acid

A multifunctional nanoplatform with core–shell structure was constructed in one-pot for the synergistic photothermal, photodynamic, and chemotherapy against breast cancer. In the presence of gambogic acid (GA) as the heat-shock protein 90 (HSP90) inhibitor and the gold nanostars (AuNS) as the photothermal reagent, the assembly of Zr⁴⁺ with tetrakis (4-carboxyphenyl) porphyrin (TCPP) gave rise to the nanocomposite AuNS@ZrTCPP-GA (AZG), which in turn, further coated with PEGylated liposome (LP) to enhance the stability and biocompatibility, and consequently the antitumor effect of the particle. Upon cellular uptake, the nanoscale metal − organic framework (NMOF) of ZrTCPP in the resulted AuNS@ZrTCPP-GA@LP (AZGL) could be slowly degraded in the weak acidic tumor microenvironment to release AuNS, Zr⁴⁺, TCPP, and GA to exert the synergistic treatment of tumors via the combination of AuNS-mediated mild photothermal therapy (PTT) and TCPP-mediated photodynamic therapy (PDT). The introduction of GA serves to reduce the thermal resistance of the cell to re-sensitize PTT and the constructed nanoplatform demonstrated remarkable anti-tumor activity in vitro and in vivo. Our work highlights a facile strategy to prepare a pH-dissociable nanoplatform for the effective synergistic treatment of breast cancer.

Drug Self-delivery Nanorods Enhance Photodynamic Therapy of Triple-Negative Breast Cancer by inhibiting Oxidative Phosphorylation

Photodynamic therapy (PDT) shows very high potential for the clinical treatment of triple-negative breast cancer. However, the efficacy of PDT is significantly weakened by tumor hypoxia, the relatively high intracellular glutathione levels and the active proliferation of cancer cells. To address these issues, we developed a novel drug self-delivery nanorod (defined as AINRs) through the hydrophobic interaction among the mitochondrial complex III inhibitor (atovaquone, ATO), the photosensitizer (indocyanine green, ICG) and the dispersion stabilizer (distearoyl phosphoethanolamine-polyethylene glycol 2000, DSPE-PEG 2000). The AINRs showed a rod-like morphology with a mean diameter of 120.6 ± 5.4 nm, a zeta potential of -26.35 ± 1.63 mV and a significantly high drug loading rate of 93.48%. The results of in vitro cell experiments involving triple-negative breast cancer cell lines (4T1 cells and MDA-MB-231 cells) indicated that the AINRs could effectively block the oxidative phosphorylation of cancer cells through the inhibition of mitochondrial complex III, which results in the reduction of endogenous oxygen consumption and the decrease of the intracellular ATP level. The reduction of ATP content further inhibited the glutathione synthesis and arrested the cell cycle at the S-phase, which results in enhanced in vitro PDT efficacy of ICG. The results of in vivo antitumor activity in 4T1-bearing mice showed that the tumor growth inhibition rate of the AINRs with near-infrared laser irradiation (NIR) was 90%, whereas the tumor growth inhibition rates of the AINRs without NIR, ICG with NIR and doxorubicin (3 mg/kg) were only 31.68%, 61.15% and 24.59%, respectively. In addition, the results of safety studies, including body weights, biochemical indicators and H&E staining images of the main organs demonstrated the security of the AINRs. In summary, this study showed that the oxidative phosphorylation inhibition of triple-negative breast cancer was a safe and effective method to enhance its PDT efficacy.

Recent Advance of Nanomaterial-Mediated Tumor Therapies in the Past Five Years

Cancer has posed a major threat to human life and health with a rapidly increasing number of patients. The complexity and refractory of tumors have brought great challenges to tumor treatment. In recent years, nanomaterials and nanotechnology have attracted more attention and greatly improved the efficiency of tumor therapies and significantly prolonged the survival period, whether for traditional tumor treatment methods such as radiotherapy, or emerging methods, such as phototherapy and immunotherapy, sonodynamic therapy, chemodynamic therapy and RNA interference therapeutics. Various monotherapies have obtained positive results, while combination therapies are further proposed to prevent incomplete eradication and recurrence of tumors, strengthen tumor killing efficacy with minimal side effects. In view of the complementary promotion effects between different therapies, it is vital to utilize nanomaterials as the link between monotherapies to achieve synergistic performance. Further development of nanomaterials with efficient tumor-killing effect and better biosafety is more in line with the needs of clinical treatment. In a word, the development of nanomaterials provides a promising way for tumor treatment, and here we will review the emerging nanomaterials towards radiotherapy, phototherapy and immunotherapy, and summarized the developed nanocarriers applied for the tumor combination therapies in the past 5 years, besides, the advances of some other novel therapies such as sonodynamic therapy, chemodynamic therapy, and RNA interference therapeutics have also been mentioned.

Applications and Biocompatibility of Mesoporous Silica Nanocarriers in the Field of Medicine

Mesoporous silica nanocarrier (MSN) preparations have a wide range of medical applications. Studying the biocompatibility of MSN is an important part of clinical transformation. Scientists have developed different types of mesoporous silica nanocarriers (MSNs) for different applications to realize the great potential of MSNs in the field of biomedicine, especially in tumor treatment. MSNs have achieved good results in diagnostic bioimaging, tissue engineering, cancer treatment, vaccine development, biomaterial application and diagnostics. MSNs can improve the therapeutic efficiency of drugs, introduce new drug delivery strategies, and provide advantages that traditional drugs lack. It is necessary not only to innovate MSNs but also to comprehensively understand their biological distribution. In this review, we summarize the various medical uses of MSN preparations and explore the factors that affect their distribution and biocompatibility in the body based on metabolism. Designing more reasonable therapeutic nanomedicine is an important task for the further development of the potential clinical applications of MSNs.

An exosome-mimicking membrane hybrid nanoplatform for targeted treatment toward Kras-mutant pancreatic carcinoma

Pancreatic carcinoma elevates quickly and thus has a high mortality rate. Therefore, early treatment is essential for treating pancreatic carcinoma. KRAS is the most frequently identified and one of the earliest mutations in pancreatic tumorigenesis. Thus, the KRAS-mutant cell is an ideal target for the treatment of pancreatic carcinoma, especially at the early stage. KRAS mutation increases macropinocytosis in pancreatic cancer cells, enhancing the internalization of exosomes. Because acquiring natural exosomes could be laborious and their encapsulation efficiency is often unsatisfactory, we aimed to develop a delivery system that mimics the Kras-mutant cell targeting capability of exosomes but is easier to generate and has better loading efficiency. For this purpose, we constructed a hybrid nanoplatform by fusing CLT (Celastrol)-Loaded PEGylated lipids with the DC2.4 cell membrane (M-LIP-CLT) to achieve targeted treatment of Kras-mutant pancreatic cancer. This hybrid nanoplatform improved CLT tumor accumulation and showed excellent anti-cancer efficiency both in vitro and in vivo with increased safety. These results suggest that M-LIP-CLT is an effective drug delivery system for targeted therapy against pancreatic carcinoma, and the fusion strategy showed attractive potential for further development.

Autophagy Modulation and Synergistic Therapy to Combat Multidrug Resistance Breast Cancer Using Hybrid Cell Membrane Nanoparticles

The development of multidrug resistance (MDR) is a commonly observed phenomenon in many cancer types. It contributed significantly to the poor outcome of many currently available chemotherapies. Considering autophagy as one of the most important physiological process in cancer progression, we thereby proposed an anti-autophagy siRNA and doxorubicin (Dox) co-delivery system (MC/D-siR) to combat MDR breast cancer using sequential construction. Our results demonstrated the potential of MC/D-siR to effectively transfect the loaded siRNA to result in significant downregulation of intracellular autophagy level in MCF-7/Adr (Dox resistance MCF-7 cell line) cells, which in turn cut off the ATP supply and to reverse the MDR and potentiated accumulated drug retention in cells. As a result, MC/D-siR showed much elevated anticancer benefits than single loaded platforms (MC/Dox or MC/siRNA), indicating the ability for effective MDR cancer treatment through the combination of autophagy regulation and chemotherapy.

Biomimetic Nanotechnology: A Natural Path Forward for Tumor-Selective and Tumor-Specific NIR Activable Photonanomedicines

The emergence of biomimetic nanotechnology has seen an exponential rise over the past decade with applications in regenerative medicine, immunotherapy and drug delivery. In the context of nanomedicines activated by near infrared (NIR) photodynamic processes (photonanomedicines; PNMs), biomimetic nanotechnology is pushing the boundaries of activatable tumor targeted nanoscale drug delivery systems. This review discusses how, by harnessing a unique collective of biological processes critical to targeting of solid tumors, biomimetic PNMs (bPNMs) can impart tumor cell specific and tumor selective photodynamic therapy-based combination regimens. Through molecular immune evasion and self-recognition, bPNMs can confer both tumor selectivity (preferential bulk tumor accumulation) and tumor specificity (discrete molecular affinity for cancer cells), respectively. They do so in a manner that is akin, yet arguably superior, to synthetic molecular-targeted PNMs. A particular emphasis is made on how bPNMs can be engineered to circumvent tumor cell heterogeneity, which is considered the Achilles’ heel of molecular targeted therapeutics. Forward-looking propositions are also presented on how patient tumor heterogeneity can ultimately be recapitulated to fabricate patient-specific, heterogeneity-targeting bPNMs.

Cell membrane cloaked nanomedicines for bio-imaging and immunotherapy of cancer: Improved pharmacokinetics, cell internalization and anticancer efficacy

Despite enormous advancements in the field of oncology, the innocuous and effectual treatment of various types of malignancies remained a colossal challenge. The conventional modalities such as chemotherapy, radiotherapy, and surgery have been remained the most viable options for cancer treatment, but lacking of target-specificity, optimum safety and efficacy, and pharmacokinetic disparities are their impliable shortcomings. Though, in recent decades, numerous encroachments in the field of onco-targeted drug delivery have been adapted but several limitations (i.e., short plasma half-life, early clearance by reticuloendothelial system, immunogenicity, inadequate internalization and localization into the onco-tissues, chemoresistance, and deficient therapeutic efficacy) associated with these onco-targeted delivery systems limits their clinical viability. To abolish the aforementioned inadequacies, a promising approach has been emerged in which stealthing of synthetic nanocarriers has been attained by cloaking them into the natural cell membranes. These biomimetic nanomedicines not only retain characteristics features of the synthetic nanocarriers but also inherit the cell-membrane intrinsic functionalities. In this review, we have summarized preparation methods, mechanism of cloaking, and pharmaceutical and therapeutic superiority of cell-membrane camouflaged nanomedicines in improving the bio-imaging and immunotherapy against various types of malignancies. These pliable adaptations have revolutionized the current drug delivery strategies by optimizing the plasma circulation time, improving the permeation into the cancerous microenvironment, escaping the immune evasion and rapid clearance from the systemic circulation, minimizing the immunogenicity, and enabling the cell-cell communication via cell membrane markers of biomimetic nanomedicines. Moreover, the preeminence of cell-membrane cloaked nanomedicines in improving the bio-imaging and theranostic applications, alone or in combination with phototherapy or radiotherapy, have also been pondered.

Liposomal Dendritic Cell Vaccine in Breast Cancer Immunotherapy

Cancer vaccine is well recognized as a promising approach for immunotherapy of cancers. Since dendritic cells (DCs) are capable of processing and presenting antigens to initiate the immune response cascade, the development of DC vaccines is considered as a good choice for the treatment of cancer. Herein, a folic acid (FA)-modified liposome was constructed and loaded with chlorin e6 (Ce6) as a DC vaccine (FA-Lipo-Ce6). It was suggested that the loaded Ce6 within FA-Lipo-Ce6 can be activated under laser irradiation. The photodynamic therapy (PDT) of Ce6 was expected to create on-demand reactive oxygen species (ROS) in situ, which causes cell death and trigger the exposure of tumor-associated antigen (TAA). In addition, the produced ROS can mimic the inflammatory responses for the employment of DC for better antigen presentation and immune response. Most importantly, the employment of DC can recognize the exposed TAA to stimulate DC for effective vaccination in situ. Our results demonstrated the powerful capacity of FA-Lipo-Ce6 to induce DC activation, leading to effective suppression of the growth of breast cancers.

Red Blood Cell Membrane-Coated Silica Nanoparticles Codelivering DOX and ICG for Effective Lung Cancer Therapy

The effective chemotherapy of cancer is usually hindered by the unsatisfied cell internalization of the drug delivery systems (DDS) as well as drug resistance of cancer cells. In order to solve these dilemmas in one design, red blood cell membrane (RBM)-coated silica nanoparticles (RS) were fabricated to codeliver doxorubicin (Dox) and indocyanine green (ICG) to effectively treat the model lung cancer using photothermal-assisted chemotherapy. Our results demonstrated that the RS/I-D was the nanoparticle at around 100 nm with superior stability and biocompatibility. Especially, the photothermal effects of ICG were well preserved and could be applied to accelerate the drug release from the DDS. More importantly, the RBM modification can mediate enhanced cell internalization of drugs as compared to their free forms, which finally resulted in enhanced anticancer efficacy in Dox-resistant A549 cells (A549/Dox) both in vitro and in vivo with enhanced cell apoptosis and cell arrest.

Chondroitin sulfate modified and adriamycin preloaded hybrid nanoparticles for tumor-targeted chemotherapy of lung cancer

Promising cancer treatment requires the assistant of drug delivery systems (DDS) with the aim to increase the accumulation of drugs in tumor tissue. Herein, a hybrid DDS was successfully developed to integrate chondroitin sulfate (CS) and calcium carbonate (CC) in to one system. Anticancer drug adriamycin (Adr) was preloaded into CC nanoparticles to obtain Adr-loaded CC nanoparticles (CC/Adr). The resulted CS-CC/Adr nanoparticles as a biocompatible DDS was able to specifically target cancer cells to enhance the chemotherapy of lung cancer due to the surface modification of CS. Intracellular uptake as well as in vivo imaging results revealed the obtained CS-CC/Adr nanoparticles (size of ~100 nm) showed CS mediated tumor specific accumulation into A549 and LLC cells than unmodified CC/Adr, in which the CD44 receptor might be involved, which finally resulted in stronger anticancer capability than Adr or CC/Adr. As a result, CS-CC/Adr nanoparticles could be further extended to clinical administration in our future works.

Harnessing the nano-bio interface: Application of membrane coating to long acting silica particles

Interaction of conventional drug delivery systems such as polymeric or lipid based nano- and microparticles with the in vivo milieu has garnered significant interest, primarily to orchestrate immune escape and/or improve targeting. Surface modification with targeting ligands has been heavily relied upon for the mentioned purpose in the recent years. However, the surface modified particles can also activate the immune system. Large-scale manufacturing can also be a challenge, as surface modification needs to be reproducible. Furthermore, in vivo, the targeting is dependent on the receptor expression density and number of target sites, which adds to the pharmacokinetic variability of the constructs. An evolving paradigm to overcome complications of surface functionalization is the incorporation of bio-inspired topographies into these conventional delivery systems to enable them to better interact with biological systems. Biomimetic delivery systems combine the unique surface composition of cells or cell membranes, and versatility of synthetic nanoparticles. In this review, we focus on one such delivery system, silica particles, and explore their interaction with different biological membranes.

Biomimetic nanoarchitecturing: A disguised attack on cancer cells

With the changing face of healthcare, there is a demand for drug delivery systems that have increased efficacy and biocompatibility. Nanotechnology derived drug carrier systems were found to be ideal candidates to meet these demands. Among the vast number of nanosized delivery systems, biomimetic nanoparticles have been researched at length. These nanoparticles mimic cellular functions and are highly biocompatible. They are also able to avoid clearance by the reticuloendothelial system which increases the time spent by them in the systemic circulation. Additionally, their low immunogenicity and targeting ability increase their significance as drug carriers. Based on their core material we have summarized them as biomimetic inorganic nanoparticles, biomimetic polymeric nanoparticles, and biomimetic lipid nanoparticles. The core then may be coated using membranes derived from erythrocytes, cancer cells, leukocytes, stem cells, and other membranes to endow them with biomimetic properties. They can be used for personalized therapy and diagnosis of a large number of diseases, primarily cancer. This review summarizes the various therapeutic approaches using biomimetic nanoparticles along with their applications in the field of cancer imaging, nucleic acid therapy and theranostic properties. A brief overview about toxicity concerns related to these nanoconstructs has been added to provide knowledge about biocompatibility of such nanoparticles.

Advances and perspectives in carrier-free nanodrugs for cancer chemo-monotherapy and combination therapy

Nanocarrier-based drug delivery systems hold impressive promise for biomedical application because of their excellent water dispersibility, prolonged blood circulation time, increased drug accumulation in tumors, and potential in combination therapeutics. However, most nanocarriers suffer from low drug-loading efficiency, poor therapeutic effectiveness, potential systematic toxicity, and unstable metabolism. As an alternative, carrier-free nanodrugs, completely formulated with one or more drugs, have attracted increasing attention in cancer therapy due to their advantage of improved pharmacodynamics/pharmacokinetics, reduced toxicity, and high drug-loading. In recent years, carrier-free nanodrugs have contributed to progress in a variety of therapeutic modalities. In this review, different common strategies for carrier-free nanodrugs preparation are first summarized, mainly including nanoprecipitation, template-assisted nanoprecipitation, thin-film hydration, spray-drying technique, supercritical fluid (SCF) technique, and wet media milling. Then we describe the recently reported carrier-free nanodrugs for cancer chemo-monotherapy or combination therapy. The advantages of anti-cancer drugs combined with other chemotherapeutic, photosensitizers, photothermal, immunotherapeutic or gene drugs have been demonstrated. Finally, a future perspective is introduced to highlight the existing challenges and possible solutions toward clinical application of currently developed carrier-free nanodrugs, which may be instructive to the design of effective carrier-free regimens in the future.

A cell membrane vehicle co-delivering sorafenib and doxorubicin remodel the tumor microenvironment and enhance immunotherapy by inducing immunogenic cell death in lung cancer cells

Cancer immunotherapy is a promising approach for cancer therapy but is usually hindered by the inhibition of the tumor microenvironment (TME). Herein, we developed a cell membrane vehicle (CV) to co-deliver doxorubicin (Dox) and sorafenib (Sfn) as a drug delivery system (CV/D-S) to regulate the TME and sensitize the immunogenic cell death (ICD)-induced immune response against tumors. The CV/D-S showed high stability, acid-responsive drug release, high biocompatibility with tumor-specific cellular uptake, and target-ability that preferably resulted in the in vitro and in vivo anticancer performance. Most importantly, the Dox in the DDS can induce significant ICD while Sfn was able to remodel the TME, downregulate Treg, activate effector T cells and relieve programmed cell death protein 1 (PD-1) expression. As a result, the synergistic effect of Dox and Sfn achieved strong immune response in CV/D-S treated mice, which is believed to open a new window for the design and development of future platforms for the more effective immunotherapy of cancer.

Mirror siRNAs loading for dual delivery of doxorubicin and autophagy regulation siRNA for multidrug reversing chemotherapy

The multidrug resistance (MDR) which widely observed in multiple cancer types is responsible for the poor chemotherapy benefits of doxorubicin (Dox). Here in our study, Dox was firstly loaded into a scramble siRNA and then condensed by polyethyleneimine (PEI) 25k together with anti-autophagy siRNA, the obtained PEI/Si-D containing mirror RNAs was further coated with hyaluronic acid (HA) to shield the surface charge of PEI and offer tumor-homing property that finally developed a platform for effective cancer chemotherapy (HP/Si-D). Our results revealed that the obtained HP/Si-D was showed high stability and biocompatibility with promising transfection profile. As a result, the anti-autophagy siRNA downregulated autophagy level of target cells, which further decreased ATP supply to enhance drug retention and cell cycle arrest. These results contributed significantly to reverse the MDR of A549/Dox (Dox resistance A549 cell line) cells with promising in vitro and in vivo results, which suggested the potential of effective MDR cancer therapy using synergistic anti-autophagy and chemotherapy.

iRGD-targeted hybrid nanoparticles reverses multi-drug resistant to effectively combat liver cancer

The off-target delivery as well as multi-drug resistance (MDR) are generally recognised as two keys difficulties responsible for the poor performance of chemotherapy in clinical treatment of cancer. With the aim to address the problems, we herein constructed iRGD modified and lipid-coated silica (LSC) nanoparticles co-delivering Ca²⁺ channel siRNA and adriamycin (Adr) to reverse the MDR in liver cancer (LSC/R-A). The iRGD decoration was suggested to elevate the tumour accumulation of the drug delivery system (DDS). In addition, the introduction of Ca²⁺ channel siRNA was proved to reverse the MDR within the cells of cancer by regulation the T-type Ca²⁺ channels. Our results showed that decreased expression of T-type Ca²⁺ channels resulted in lowered cytosolic Ca²⁺ level responsible for the cell cycle arrest (at G0/G1 phase) as well as elevated cellular drug retention in HepG2/Adr. B in vitro/in vivo experiments revealed that LSC/R-A exerted highly elevated therapeutic outcome on HepG2/Adr, than administration of single siRNA or Adr.

Chitosan derived glycolipid nanoparticles for magnetic resonance imaging guided photodynamic therapy of cancer

Currently, the development of polysaccharide, especially chitosan (CS), based drug delivery system to afford magnetic resonance imaging (MRI) guided theranostic cancer therapy remains largely unexplored. Herein, we successfully developed a CS derived polymer (Gd-CS-OA) through chemical conjugation of CS, octadecanoic acid (OA) and gadopentetic acid (GA). After self-assemble into glycolipid nanoparticles to loaded chlorin e6 (Ce6), the resulted Gd-CS-OA/Ce6 was able to realize MRI guided photodynamic therapy (PDT) of cancer. Our results revealed that Gd-CS-OA was able to increase the MRI sensitivity as compared to Gd-DTPA with decent residence time and preferable excretion behavior in vivo. Moreover, the Gd-CS-OA/Ce6 showed negligible hemolysis, satisfactory ROS generation and stability in physiological environments with preferable cellular uptake and enhanced in vitro cytotoxicity (through elevated ROS generation) on 4T1 cells. Most importantly, Gd-CS-OA/Ce6 demonstrated promising in vivo tumor targetability (enhanced penetration and retention effect) and powerful MRI guided tumor ablation through PDT on in situ 4T1 tumor model.

Influence of the Surface Functionalization on the Fate and Performance of Mesoporous Silica Nanoparticles

Mesoporous silica nanoparticles have been broadly applied as drug delivery systems owing to their exquisite features, such as excellent textural properties or biocompatibility. However, there are various biological barriers that prevent their proper translation into the clinic, including: (1) lack of selectivity toward tumor tissues, (2) lack of selectivity for tumoral cells and (3) endosomal sequestration of the particles upon internalization. In addition, their open porous structure may lead to premature drug release, consequently affecting healthy tissues and decreasing the efficacy of the treatment. First, this review will provide a comprehensive and systematic overview of the different approximations that have been implemented into mesoporous silica nanoparticles to overcome each of such biological barriers. Afterward, the potential premature and non-specific drug release from these mesoporous nanocarriers will be addressed by introducing the concept of stimuli-responsive gatekeepers, which endow the particles with on-demand and localized drug delivery.

Cell membrane-camouflaged nanoparticles as drug carriers for cancer therapy

The translocation of natural cell membranes to the surface of synthetic nanoparticles, which allows man-made vectors to share merits and functionalities created by nature, has been a hot subject of research in the past decade. The resulting biomimetic nanoparticles not only retain the physicochemical properties of nanomaterials, but also inherit the advantageous functions of source cells. Combined with the preponderances of both synthetic and natural platforms, the optimized biomimetic systems can maximize the drug delivery efficiency. In this review, we first summarize the preparation strategies of the biomimetic systems from the perspective of the correlation between the properties of nanoparticles and cell membranes. Six types of cell membrane-camouflaged nanoparticles are further introduced with an emphasis on their properties and performance. Finally, a concluding remark regarding the primary challenges and opportunities associated with these nanoparticles is presented. STATEMENT OF SIGNIFICANCE: Translocation of natural cell membranes to the surface of synthetic nanoparticles has been repeatedly highlighted in the past decade to endow man-made vectors with merits and functionalities created by nature; therefore, the resulting biomimetic systems not only retain the physicochemical properties of nanomaterials but also inherit the biological functions of source cells for efficient drug delivery. To provide a timely review on this hot and rapidly developing subject of research, this paper summarized recent progress on the cell membrane-camouflaged nanoparticles as drug carriers for cancer therapy, and focused primarily on six different types of cell membrane-coated nanoparticles with an emphasis on the preparation strategies from the perspective of the correlation between the properties of nanoparticles and cell membrane.

Dendritic cell vaccine for the effective immunotherapy of breast cancer

Cancer vaccine is widely considered as a powerful tool in immunotherapy. In particular, the effective antigen processing and presentation natures of dendritic cell (DC) have made it a promising target for the development of therapeutic vaccine for cancer treatment. Here in our study, a versatile cancer cell membrane (CCM) coated calcium carbonate (CC) nanoparticles (MC) that capable of generating in situ tumor-associated antigens (TAAs) for DC vaccination is developed. Low-dose doxorubicin hydrochloride (Dox) could be encapsulated in the CC core of MC to trigger immunogenic cell death (ICD) while chlorins e6 (Ce6), a commonly adopted photosensitizer, was loaded in the CCM of MC for effective photodynamic therapy (PDT) through the generation of reactive oxygen species (ROS) to finally construct the vaccine (MC/Dox/Ce6). Most importantly, our in-depth study revealed the treatment of MC/Dox/Ce6 was able to elicit TAAs population and DC recruitment, triggering the following immune response cascade. In particular, the recruited DC cells could be stimulated in situ for effective vaccinations. Both in vitro and in vivo experiments suggested the capability of this all-in-one DDS to enhance DCs maturation to finally result in effective inhibition of both primary and distant growth of breast cancer upon single administration of low dose Dox and Ce6.

Ca2+ signaling modulation using cancer cell membrane coated chitosan nanoparticles to combat multidrug resistance of cancer

Off-target drug delivery, together with multidrug resistance (MDR), are two keys obstacles that account for the disappointing outcome in clinical chemotherapy of cancer. To solve these dilemmas, Herein, we constructed cancer cell membrane (CCM) modified silica (CS) nanoparticles (CCM/CS) to co-deliver Ca²⁺ channel siRNA with doxorubicin (DOX) to construct a platform (CCM/CS/R-D) for the efficient therapy of cervical cancer. It was demonstrated that the optimal CCM/CS/R-D was spherical nanoparticles with size at 122.39 ± 4.69 nm and the surface charge of -27.76 ± 3.12 mV. In addition, the CCM/CS/R-D showed acid responsive drug release while high stability under physiological conditions with negligible hemolysis. The CCM/CS/R-D showed CCM mediated cellular uptake and efficient endosomal escape as well as siRNA transfection potential (comparable to that of PEI 25 K) on MDR cervical cancer cells (HeLa/DOX). Most importantly, the MDR of cancer cells was conquered through modulation of T-type Ca²⁺ (Cav) channels. It was observed that the Cav channel siRNA could negatively regulate the level of cytosolic Ca²⁺ concentration which triggered G0/G1 phase cell cycle arrest and elevated intracellular drug retention in HeLa/DOX cells without significantly affect the expression of P-glycolprotein (P-gp). The in vitro and in vivo experiments revealed that CCM/CS/R-D exerted greatly enhanced tumor targetability and therapeutic effect on HeLa/DOX, which was superior than CS/R-D or mono delivery system (CCM/CS/R or CCM/CS/D).

Cell Membrane-Camouflaged Nanocarriers for Cancer Diagnostic and Therapeutic

Cell membrane (CM)-camouflaged nanocarriers (CMNPs) are the tools of a biomimetic strategy that has attracted significant attention. With a wide range of nanoparticle cores and CMs available, various creative CMNP designs have been studied for cancer diagnosis and therapy. The various functional CM molecules available allow CMNPs to demonstrate excellent properties such as prolonged circulation time, immune escape ability, reduced systemic toxicity, and homologous targeting ability when camouflaged with CMs derived from various types of natural cells including red and white blood cells, platelets, stem cells, and cancer cells. In this review, we summarize various CMNPs employed for cancer chemotherapy, immunotherapy, phototherapy, and in vivo imaging. We also predict future challenges and opportunities for fundamental and clinical studies.

Biomimetic Nanoparticles Camouflaged in Cancer Cell Membranes and Their Applications in Cancer Theranostics

Nanoparticles (NPs) camouflaged in cell membranes represent novel biomimetic platforms that can mimic some of the membrane functions of the cells from which these membranes are derived, in biological systems. Studies using cell membrane coated NPs cover a large repertoire of membranes derived from cells such as red blood cells, immune cells, macrophages, and cancer cells. Cancer cell membrane coated nanoparticles (CCMCNPs) typically consist of a NP core with a cancer cell plasma membrane coat that can carry tumor-specific receptors and antigens for cancer targeting. The NP core can serve as a vehicle to carry imaging and therapeutic moieties. As a result, these CCMCNPs are being investigated for multiple purposes including cancer theranostics. Here we have discussed the key steps and major issues in the synthesis and characterization of CCMCNPs. We have highlighted the homologous binding mechanisms of CCMCNPs that are being investigated for cancer targeting, and have presented our data that identify BT474 CCMCNPs as binding to multiple cancer cell lines. Current preclinical applications of CCMCNPs for cancer theranostics and their advantages and limitations are discussed.

Development of Drug Dual-Carriers Delivery System with Mitochondria-Targeted and pH/Heat Responsive Capacity for Synergistic Photothermal-Chemotherapy of Ovarian Cancer

PURPOSE

Multifunctional drug delivery systems (DDS) are emerging as a new strategy to highly treat malignant tumors. The aim of this study is to develop a drug dual-carriers delivery system (DDDS) using the natural protein ferritin (FRT) and a nanoscale graphene oxide (NGO) as dual-carriers.

METHODS

The FRT is a pH-sensitive hollow cage protein with disassembly and reassembly properties and the NGO has a large surface area and a photothermal effect by which it can load and release drugs under near-infrared irradiation (NIR). Due to these unique features, the NGO loaded the anticancer drug resveratrol (RSV) and the conjugated mitochondrion targeted molecule IR780 as IR780-NGO-RSV (INR), the first drug delivery platform. Next, the INR was capsulated by FRT to form the DDDS INR@FRT which was applied for synergistic photothermal-chemotherapy of ovarian cancer.

RESULTS

Through a series of characterizations, INR@FRT showed a uniform nanosphere structure and remarkable stability in physiological condition. Heat/pH 5.0 was confirmed to trigger RSV release from the INR@FRT. After taken up by cells, INR@FRT located to the lysosomes where the acidic environment triggered INR release. INR targeted the mitochondrion and released RSV to directly react with organelles, which in turn decreased the mitochondrion membrane potential and caused cell apoptosis. In-vivo experiments showed that INR@FRT combined with NIR irradiation displayed remarkable tumor suppression with a high survival rate after 60 days of treatment. Finally, the biocompatibility of INR@FRT was demonstrated in vitro and in vivo.

CONCLUSION

These results highlight the immense potential of INR@FRT as a type of DDDS for the treatment of tumors.

Nanostructured lipid carrier delivering chlorins e6 as in situ dendritic cell vaccine for immunotherapy of gastric cancer

The recent scientific progress has shown the promising effect of the vaccine in immunotherapy of cancer, which relies on the antigen processing/presentation capability of dendritic cells (DCs). As a result, cancer vaccines targeting DC, which also named as DC vaccine, was a hot-spot in vaccine development. Herein, a nanostructured lipid carrier (NLC) was employed to load chlorin e6 (Ce6) to serve as a potential in situ DC vaccine (NLC/Ce6) for effective immunotherapy of gastric cancer. Taking advantage of the photodynamic effect of Ce6 to generate reactive oxygen species (ROS) under laser irradiation, the NLC/Ce6 was able to trigger cell death and expose tumor-associated antigen (TAA). Moreover, mimicking the natural inflammatory response, the ROS can also recruit the DC for the effective processing/presentation of the in situ exposed TAA. As expected, we observed strong capability DC vaccination efficacy of this platform to effectively inhibit the growth of both primary and distant gastric tumors.

Cell Membrane Coating Technology: A Promising Strategy for Biomedical Applications

Cell membrane coating technology is an approach to the biomimetic replication of cell membrane properties, and is an active area of ongoing research readily applicable to nanoscale biomedicine. Nanoparticles (NPs) coated with cell membranes offer an opportunity to unite natural cell membrane properties with those of the artificial inner core material. The coated NPs not only increase their biocompatibility but also achieve effective and extended circulation in vivo, allowing for the execution of targeted functions. Although cell membrane-coated NPs offer clear advantages, much work remains before they can be applied in clinical practice. In this review, we first provide a comprehensive overview of the theory of cell membrane coating technology, followed by a summary of the existing preparation and characterization techniques. Next, we focus on the functions and applications of various cell membrane types. In addition, we collate model drugs used in cell membrane coating technology, and review the patent applications related to this technology from the past 10 years. Finally, we survey future challenges and trends pertaining to this technology in an effort to provide a comprehensive overview of the future development of cell membrane coating technology.

Carrier-Free, Dual-Functional Nanorods Via Self-Assembly Of Pure Drug Molecules For Synergistic Chemo-Photodynamic Therapy

BACKGROUND

The combination of chemo-photodynamic therapy based on nano-technology has emerged as a preferable and promising measure for synergetic antitumor therapy.

PURPOSE

The aim of this study was expected to overcome most of the safety concerns from nano-carriers and improve the chemo-photodynamic synergistic antitumor efficacy.

METHODS

Herein, we reported a facile and effective approach based on the self-assembly of chemotherapeutic agent 10-hydroxycamptothecin (HCPT) and photosensitizer chlorin e6 (Ce6) for preparing stably dual-functional nanorods (NRs).

RESULTS

The chemical thermodynamic parameters obtained from isothermal titration calorimeter (ITC) and the microcosmic configuration snapshots acquired by molecular dynamics (MD) simulations verified that HCPT and Ce6 molecules tended to assemble with each other through various intermolecular forces. The as-prepared HCPT/Ce6 NRs possessed a relatively uniform size of around 165 nm and zeta potential of about -29 mV, together with good stability in aqueous solution and freeze-dried state. In addition, both the extra- and intracellular reactive oxygen species (ROS) generation capacity of the NRs under laser irradiation was significantly enhanced compared with Ce6 injections. Moreover, the dual-functional HCPT/Ce6 NRs exhibited a substantial in vitro/in vivo synergistic antitumor efficacy under laser irradiation due to the integration of the two therapeutic modalities into one drug delivery system. Besides, no obvious hepatic or renal toxicity was observed in the NRs treatment groups.

CONCLUSION

Taken together, HCPT/Ce6 NRs demonstrated a powerful efficacy in chemo-photodynamic therapy for breast cancer. Therefore, the carrier-free dual-functional NRs prepared in a facile and effective strategy might give inspiration for the development of combined antitumor therapy.