Recent progress in cancer immunotherapy approaches based on nanoparticle delivery devices

PROTAC Delivery Strategies for Overcoming Physicochemical Properties and Physiological Barriers in Targeted Protein Degradation

Proteolysis targeting chimeras (PROTACs), heterobifunctional molecules that hijack the ubiquitin-proteasome system (UPS) to degrade specific proteins, hold great promise in treating diseases driven by traditionally "undruggable" targets. However, their large molecular weight, high hydrophobicity, and other physicochemical hurdles contribute to their limited bioavailability, suboptimal pharmacokinetics, and attenuated therapeutic efficacy. Consequently, diverse formulation innovations have been investigated to optimize PROTAC delivery. This review examines current challenges and advances in specialized drug delivery approaches designed to bolster PROTAC pharmacological performance. We first outline the fundamental limitations of PROTACs-their low aqueous solubility, poor cell permeability, rapid clearance, and concentration-dependent "hook effect". We then discuss how various enabling formulations address these issues, including polymeric micelles, emulsions, amorphous solid dispersions, lipid-based nanoparticles, liposomes, and exosomes. Collectively, these delivery technologies substantially improve the therapeutic outcomes of PROTACs in preclinical cancer models. Future applications may extend beyond oncology to address other complex diseases using newly emerging heterobifunctional molecules. By integrating advanced formulation science with innovative degrader design, the field stands poised to unlock the clinical potential of PROTACs for protein degradation therapies.

Fabrication and evaluation of chitosan-coated nanostructured lipid carriers for co-delivery of paclitaxel and PD-L1 siRNA

This study aimed to develop a nanostructured lipid carrier (NLC) capable of co-delivering paclitaxel (PTX) and programmed death-ligand 1 (PD-L1) small interfering RNA (siRNA) to enhance PTX bioavailability and bolster immunity through PD-L1 knockdown. We prepared a PTX-loaded NLC (P-NLC) and coated it with positively charged chitosan (Chi) to create P-NLC-Chi, which was subsequently conjugated to siRNA (P-NLC-Chi-siRNA). The P-NLC-Chi formulation was optimized using the Box-Behnken design. P-NLC-Chi measured 123.8 ± 0.52 nm (zeta potential, 22.71 ± 0.49 mV). By verifying the gel retardation assay and observing changes in the zeta potential, the optimal binding ratio of NLC to PD-L1 siRNA was identified as 50:1. The P-NLC-Chi-siRNA particle size was 181.97 ± 0.67 nm, with a zeta potential of 18.66 ± 0.23 mV. siRNA stability was observed in serum over a 24-h period. Enhanced cytotoxicity and intracellular uptake of the complex were evident in breast cancer cells and breast cancer-resistant cells (MCF-7 and MCF-7/ADR cells, respectively). Evaluation of P-glycoprotein-mediated efflux demonstrated that NLC mitigated drug efflux in MCF-7/ADR cells. Subcutaneous injection of P-NLC-Chi-siRNA into tumor-bearing BALB/c nude mice injected with MCF-7/ADR cells revealed a reduction in tumor size. In vitro and in vivo experiments indicated a significant reduction in PD-L1 mRNA expression levels. Additionally, an in vivo study revealed tumor-specific CD4 + and CD8 + T cell responses within the tumor tissue following the injection of P-NLC-Chi-siRNA. Our findings suggest that Chi-coated NLC for the co-delivery of PTX and PD-L1 siRNA has great potential as an innovative delivery system for chemoimmunotherapy.

Alum-tuned hyaluronic acid-based hydrogel with immune checkpoint inhibition for immunophoto therapy of cancer

Alum-crosslinked hyaluronic acid-dopamine (HD) hydrogel containing indocyanine green (ICG) with anti-programmed cell death-1 (PD-1) antibody (Ab) administration was developed for immunophoto therapy of cancer. Alum modulates the rheological characteristics of hydrogel for enabling syringe injection, shear-thinning feature, and slower biodegradation. In addition, alum in HD-based hydrogel provided CD8+ T cell-mediated immune responses for cancer therapy. ICG in the hydrogel under near-infrared (NIR) light exposure may induce hyperthermia and generate singlet oxygen for selective cancer cell killing. HD/alum/ICG hydrogel injection with NIR laser irradiation elevated PD-1 level in CD8+ T cells. Administration of PD-1 Ab aiming at highly expressed PD-1 in T cells may amplify the anticancer efficacies of HD/alum/ICG hydrogel along with NIR laser. HD/alum/ICG hydrogel with NIR light may have both CD8+ T cell-linked immune responses and ICG-related photodynamic/photothermal effects. Additional injection of immune checkpoint inhibitor can ultimately suppress primary and distant tumor growth by combination with those therapeutic actions.

Nanorod/nanodisk-integrated liquid crystalline systems for starvation, chemodynamic, and photothermal therapy of cancer

Indocyanine green (ICG), glucose oxidase (GOx), and copper(II) sulfate (Cu)-installed hybrid gel based on organic nanorod (cellulose nanocrystal [CNC]) and inorganic nanodisk (Laponite [LAP]) was developed to perform a combination of starvation therapy (ST), chemodynamic therapy (CDT), and photothermal therapy (PTT) for localized cancers. A hybrid CNC/LAP network with a nematic phase was designed to enable instant gelation, controlled viscoelasticity, syringe injectability, and longer in vivo retention. Moreover, ICG was introduced into the CNC/LAP gel system to induce hyperthermia of tumor tissue, amplifying the CDT effect; GOx was used for glucose deprivation (related to the Warburg effect); and Cu was introduced for hydroxyl radical generation (based on Fenton-like chemistry) and cellular glutathione (GSH) degradation in cancer cells. The ICG/GOx/Cu-installed CNC/LAP gel in combination with near-infrared (NIR) laser realized improved antiproliferation, cellular reactive oxygen species (ROS) generation, cellular GSH degradation, and apoptosis induction in colorectal cancer (CT-26) cells. In addition, local injection of the CNC/ICG/GOx/Cu/LAP gel into the implanted CT-26 tumor while irradiating it with NIR laser provided strong tumor growth suppression effects. In conclusion, the designed hybrid nanorod/nanodisk gel network can be efficiently applied to the local PTT/ST/CDT of cancer cells.

Hyaluronic acid-bilirubin nanomedicine-based combination chemoimmunotherapy

Despite significant advances in immune checkpoint blockade (ICB), immunosuppression mediated by tumor-associated myeloid cells (TAMCs) poses a major barrier to cancer immunotherapy. In addition, while immunogenic cell death (ICD) provides a viable approach to inducing anti-tumor immune response, it remains unknown how to effectively trigger ICD while addressing immunosuppressive TAMCs. Here, we show that SC144, a gp130 inhibitor that blocks the IL-6/gp130/STAT3 pathway, induces ICD of tumor cells and polarizes macrophages to M1-phenotype in vitro. However, as SC144 also induces killing of CD8+ T-cells, we sought to deliver SC144 selectively to tumor cells and TAMCs. Toward this goal, we have developed hyaluronic acid-bilirubin nanoparticles (HABN) that accumulate in CD44hi tumor cells and TAMCs. Systemic administration of SC144 loaded in HABN (SC144@HABN) induces apoptosis and ICD of tumor cells, increases the ratio of M1-like to M2-like macrophages, and decreases the frequency of myeloid-derived suppressor cells and CD4+ regulatory T-cells, while promoting anti-tumor CD8+ T-cells. Moreover, SC144@HABN combined with anti-PD-L1 ICB efficiently eliminates MC38 tumors and ICB-resistant 4T1 tumors. Overall, our work demonstrates a therapeutic strategy based on coordinated ICD induction and TAMC modulation and highlights the potential of combination chemoimmunotherapy.

Drug Delivery Systems for Personal Healthcare by Smart Wearable Patch System

Smart wearable patch systems that combine biosensing and therapeutic components have emerged as promising approaches for personalized healthcare and therapeutic platforms that enable self-administered, noninvasive, user-friendly, and long-acting smart drug delivery. Sensing components can continuously monitor physiological and biochemical parameters, and the monitoring signals can be transferred to various stimuli using actuators. In therapeutic components, stimuli-responsive carrier-based drug delivery systems (DDSs) provide on-demand drug delivery in a closed-loop manner. This review provides an overview of the recent advances in smart wearable patch systems, focusing on sensing components, stimuli, and therapeutic components. Additionally, this review highlights the potential of fully integrated smart wearable patch systems for personalized medicine. Furthermore, challenges associated with the clinical applications of this system and future perspectives are discussed, including issues related to drug loading and reloading, biocompatibility, accuracy of sensing and drug delivery, and largescale fabrication.

Effects of PEG-Linker Chain Length of Folate-Linked Liposomal Formulations on Targeting Ability and Antitumor Activity of Encapsulated Drug

Introduction

Ligand-conjugated liposomes are promising for the treatment of specific receptor-overexpressing cancers. However, previous studies have shown inconsistent results because of the varying properties of the ligand, presence of a polyethylene glycol (PEG) coating on the liposome, length of the linker, and density of the ligand.

Methods

Here, we prepared PEGylated liposomes using PEG-linkers of various lengths conjugated with folate and evaluated the effect of the PEG-linker length on the nanoparticle distribution and pharmacological efficacy of the encapsulated drug both in vitro and in vivo.

Results

When folate was conjugated to the liposome surface, the cellular uptake efficiency in folate receptor overexpressed KB cells dramatically increased compared to that of the normal liposome. However, when comparing the effect of the PEG-linker length in vitro, no significant difference between the formulations was observed. In contrast, the level of tumor accumulation of particles in vivo significantly increased when the length of the PEG-linker was increased. The tumor size was reduced by >40% in the Dox/FL-10K-treated group compared to that in the Dox/FL-2K- or 5K-treated groups.

Discussion

Our study suggests that as the length of PEG-linker increases, the tumor-targeting ability can be enhanced under in vivo conditions, which can lead to an increase in the antitumor activity of the encapsulated drug.

Emerging Trends in Nano-Driven Immunotherapy for Treatment of Cancer

Despite advancements in the development of anticancer medications and therapies, cancer still has the greatest fatality rate due to a dismal prognosis. Traditional cancer therapies include chemotherapy, radiotherapy, and targeted therapy. The conventional treatments have a number of shortcomings, such as a lack of selectivity, non-specific cytotoxicity, suboptimal drug delivery to tumour locations, and multi-drug resistance, which results in a less potent/ineffective therapeutic outcome. Cancer immunotherapy is an emerging and promising strategy to elicit a pronounced immune response against cancer. Immunotherapy stimulates the immune system with cancer-specific antigens or immune checkpoint inhibitors to overcome the immune suppressive tumour microenvironment and kill the cancer cells. However, delivery of the antigen or immune checkpoint inhibitors and activation of the immune response need to circumvent the issues pertaining to short lifetimes and effect times, as well as adverse effects associated with off-targeting, suboptimal, or hyperactivation of the immune system. Additional challenges posed by the tumour suppressive microenvironment are less tumour immunogenicity and the inhibition of effector T cells. The evolution of nanotechnology in recent years has paved the way for improving treatment efficacy by facilitating site-specific and sustained delivery of the therapeutic moiety to elicit a robust immune response. The amenability of nanoparticles towards surface functionalization and tuneable physicochemical properties, size, shape, and surfaces charge have been successfully harnessed for immunotherapy, as well as combination therapy, against cancer. In this review, we have summarized the recent advancements made in choosing different nanomaterial combinations and their modifications made to enable their interaction with different molecular and cellular targets for efficient immunotherapy. This review also highlights recent trends in immunotherapy strategies to be used independently, as well as in combination, for the destruction of cancer cells, as well as prevent metastasis and recurrence.

Dendrimers as Modifiers of Inorganic Nanoparticles for Therapeutic Delivery in Cancer

The formulation of nanoscale systems with well-defined sizes and shapes is of great interest in applications such as drug and gene delivery, diagnostics and imaging. Dendrimers are polymers that have attracted interest due to their size, shape, branching length, amine density, and surface functionalities. These unique characteristics of dendrimers set them apart from other polymers, their ability to modify nanoparticles (NPs) for biomedical applications. Dendrimers are spherical with multiple layers over their central core, each representing a generation. Their amphiphilic nature and hollow structure allow for the incorporation of multiple drugs or genes, in addition to enabling easy surface modification with cellular receptor-targeting moieties to ensure site-specific delivery of therapeutics. Dendrimers are employed in chemotherapeutic applications for the delivery of anticancer drugs. There are many inorganic NPs currently being investigated for cancer therapy, each with their own unique biological, chemical, and physical properties. To favor biomedical applications, inorganic NPs require suitable polymers to ensure stability, biodegradability and target specificity. The success of dendrimers is dependent on their unique structure, good bioavailability and stability. In this review, we describe the properties of dendrimers and their use as modifiers of inorganic NPs for enhanced therapeutic delivery. Herein, we review the significant developments in this area from 2015 to 2022. Databases including Web of Science, Scopus, Google Scholar, Science Direct, BioMed Central (BMC), and PubMed were searched for articles using dendrimers, inorganic nanoparticles and cancer as keywords.

How Advanced are Cancer Immuno-Nanotherapeutics? A Comprehensive Review of the Literature

Cancer is a broad term for a group of diseases involving uncontrolled cell growth and proliferation. There is no cure for cancer despite recent significant improvements in screening, treatment, and prevention approaches. Among the available treatments, immunotherapy has been successful in targeting and killing cancer cells by stimulating or enhancing the body's immune system. Antibody-based immunotherapeutic agents that block immune checkpoint proteins expressed by cancer cells have shown promising results. The rapid development of nanotechnology has contributed to improving the effectiveness and reducing the adverse effects of these anti-cancer immunotherapeutic agents. Recently, engineered nanomaterials have been the focus of many state-of-The-art approaches toward effective cancer treatment. In this review, the contribution of various nanomaterials such as polymeric nanoparticles, dendrimers, microspheres, and carbon nanomaterials in improving the efficiency of anti-cancer immunotherapy is discussed as well as nanostructures applied to combination cancer immunotherapy.

Nano drug delivery systems for antisense oligonucleotides (ASO) therapeutics

Cancer, infectious diseases, and metabolic and hereditary genetic disorders are a global health burden affecting millions of people, with contemporary treatments offering limited relief. Antisense technology treats diseases by targeting their causal agents using its ability to alter or inhibit endogenous or malfunctioning genes. Nine antisense oligonucleotide (ASO) drugs that represent four different chemical classes have been approved for the treatment of rare diseases, including nusinersen, the first new oligonucleotide-based drug. Advances in medicinal chemistry, understanding the molecular pathways, and the availability of vast genetic data have resulted in enormous improvements in the therapeutic performance of ASO drugs; however, their susceptibility to degradation in the circulation, rapid renal clearance, and immunostimulatory adverse effects greatly limit their clinical applications. An increasing number of ASO-based therapeutics is being tested in clinical trials. Improvements to the delivery of ASO drugs could potentially change the therapeutic landscape for many conditions in the near future. This review describes the technological advances and developments in drug delivery systems pertaining to ASO therapeutics.

Functional ligands for improving anticancer drug therapy: current status and applications to drug delivery systems

Conventional chemotherapy lacking target selectivity often leads to severe side effects, limiting the effectiveness of chemotherapy. Therefore, drug delivery systems ensuring both selective drug release and efficient intracellular uptake at the target sites are highly demanded in chemotherapy to improve the quality of life of patients with low toxicity. One of the effective approaches for tumor-selective drug delivery is the adoption of functional ligands that can interact with specific receptors overexpressed in malignant cancer cells. Various functional ligands including folic acid, hyaluronic acid, transferrin, peptides, and antibodies, have been extensively explored to develop tumor-selective drug delivery systems. Furthermore, cell-penetrating peptides or ligands for tight junction opening are also actively pursued to improve the intracellular trafficking of anticancer drugs. Sometimes, multiple ligands with different roles are used in combination to enhance the cellular uptake as well as target selectivity of anticancer drugs. In this review, the current status of various functional ligands applicable to improve the effectiveness of cancer chemotherapy is overviewed with a focus on their roles, characteristics, and preclinical/clinical applications.

Nanotherapeutics for immune network modulation in tumor microenvironments

Immunotherapy has shown promise in cancer treatment, and is thus drawing increasing interest in this field. While the standard chemotherapy- and/or radiotherapy-based cancer treatments aim to directly kill cancer cells, immunotherapy uses host immune cell surveillance to fight cancer. In the tumor environment, there is a close relationship between tumor cells and the adjacent immune cells, which are largely suppressed by cancer-related regulation of immune checkpoints, immune-suppressive cytokines, and metabolic factors. The immune modulators currently approved for cancer treatment remain limited by issues with dose tolerance and insufficient efficacy. Researchers have developed and tested various nano-delivery systems with the goal of improving the treatment outcome of these drugs. By encapsulating immune modulators in particles and directing their tissue accumulation, some such systems have decreased immune-related toxicity while sharpening the antitumor response. Surface-ligand modification of nanoparticles has allowed drugs to be delivered to specific immune cells types. Researchers have also studied strategies for depleting or reprogramming the immune-suppressive cells to recover the immune environment. Combining a nanomaterial with an external stimulus has been used to induce immunogenic cell death; this favors the inflammatory environment found in tumor tissues to promote antitumor immunity. The present review covers the most recent strategies aimed at modulating the tumor immune environment, and discusses the challenges and future perspectives in developing nanoparticles for cancer immunotherapy.

Nanoparticle-based immunotherapy of pancreatic cancer

Pancreatic cancer (PC) has a complex and unique tumor microenvironment (TME). Due to the physical barrier formed by the desmoplastic stroma, the delivery of drugs to the tumor tissue is limited. The TME also contributes to resistance to various immunotherapies such as cancer vaccines, chimeric antigen receptor T cell therapy and immune checkpoint inhibitors. Overcoming and/or modulating the TME is therefore one of the greatest challenges in developing new therapeutic strategies for PC. Nanoparticles have been successfully used as drug carriers and delivery systems in cancer therapy. Recent experimental and engineering developments in nanotechnology have resulted in increased drug delivery and improved immunotherapy for PC. In this review we discuss and analyze the current nanoparticle-based immunotherapy approaches that are at the verge of clinical application. Particularly, we focus on nanoparticle-based delivery systems that improve the effectiveness of PC immunotherapy. We also highlight current clinical research that will help to develop new therapeutic strategies for PC and especially targeted immunotherapies based on immune checkpoint inhibitors.

Targeting Cancer Stem Cells: Therapeutic and diagnostic strategies by the virtue of nanoparticles

Cancer stem cells (CSCs) are the subpopulation of cells present within a tumor with the properties of self-renewing, differentiating, and proliferating. Owing to the presence of ATP-binding cassette drug pumps and increased expression of anti-apoptotic proteins, the conventional chemotherapeutic agents have failed to eliminate CSCs resulting in relapse and resistance of cancer. Therefore, to obtain long-lasting clinical responses and avoid the recurrence of cancer, it is crucial to develop an efficient strategy targeting CSCs by either employing a differentiation therapy or specifically delivering drugs to CSCs. Several intracellular and extracellular cancer specific biomarkers are overexpressed by CSCs and are utilized as targets for the development of new approaches in the diagnosis and treatment of CSCs. Moreover, several nanostructured particles, alone or in combination with current treatment approaches, have been used to improve the detection, imaging, and targeting of CSCs, thus addressing the limitations of cancer therapies. Targeting CSC surface markers, stemness-related signaling pathways, and tumor microenvironmental signals has improved the detection and eradication of CSCs and, therefore, tumor diagnosis and treatment. This review summarizes a variety of promising nanoparticles targeting the surface biomarkers of CSCs for the detection and eradication of tumor-initiating stem cells, used in combination with other treatment regimens.

Current Strategies for the Treatment of Hepatocellular Carcinoma by Modulating the Tumor Microenvironment via Nano-Delivery Systems: A Review

Liver cancer remains a global health challenge with a projected incidence of over one million cases by 2025. Hepatocellular carcinoma (HCC) is a common primary liver cancer, accounting for about 90% of all liver cancer cases. The tumor microenvironment (TME) is the internal and external environment for tumor development, which plays an important role in tumorigenesis, immune escape and treatment resistance. Knowing that TME is a unique setting for HCC tumorigenesis, exploration of strategies to modulate TME has attracted increasing attention. Among them, the use of nano-delivery systems to deliver therapeutic agents to regulate TME components has shown great potential. TME-modulating nanoparticles have the advantages of protecting therapeutic agents from degradation, enhancing the ability of targeting HCC and reducing systemic toxicity. In this article, we summarize the TME components associated with HCC, including cancer-associated fibroblasts (CAFs), extracellular matrix (ECM), endothelial cells and immune cells, discuss their impact on the HCC progression, and highlight recent studies on nano-delivery systems that modulate these components. Finally, we also discuss opportunities and challenges in this field.

Pharmaceutical Applications of Supercritical Fluid Extraction of Emulsions for Micro-/Nanoparticle Formation

Micro-/nanoparticle formulations containing drugs with or without various biocompatible excipients are widely used in the pharmaceutical field to improve the physicochemical and clinical properties of the final drug product. Among the various micro-/nanoparticle production technologies, emulsion-based particle formation is the most widely used because of its unique advantages such as uniform generation of spherical small particles and higher encapsulation efficiency (EE). For this emulsion-based micro-/nanoparticle technology, one of the most important factors is the extraction efficiency associated with the fast removal of the organic solvent. In consideration of this, a technology called supercritical fluid extraction of emulsions (SFEE) that uses the unique mass transfer mechanism and solvent power of a supercritical fluid (SCF) has been proposed to overcome the shortcomings of several conventional technologies such as solvent evaporation, extraction, and spray drying. This review article presents the main aspects of SFEE technology for the preparation of micro-/nanoparticles by focusing on its pharmaceutical applications, which have been organized and classified according to several types of drug delivery systems and active pharmaceutical ingredients. It was definitely confirmed that SFEE can be applied in a variety of drugs from water-soluble to poorly water-soluble. In addition, it has advantages such as low organic solvent residual, high EE, desirable release control, better particle size control, and agglomeration prevention through efficient and fast solvent removal compared to conventional micro-/nanoparticle technologies. Therefore, this review will be a good resource for determining the applicability of SFEE to obtain better pharmaceutical quality when researchers in related fields want to select a suitable manufacturing process for preparing desired micro-/nanoparticle drug delivery systems containing their active material.

Preparation and evaluation of dabrafenib-loaded, CD47-conjugated human serum albumin-based nanoconstructs for chemoimmunomodulation

The transmembrane proteins, CD47 and signal-regulatory protein α are overexpressed in cancer cells and macrophages, respectively, and facilitate the escape of cancer cells from macrophage-mediated phagocytosis. The immunomodulatory and targeting properties of CD47, the chemotherapeutic effects of dabrafenib (D), and the anti-programmed death-1 antibodies (PD-1) pave the way for effective chemoimmunomodulation-mediated anticancer combination therapy. In this study, CD47-conjugated, D-loaded human serum albumin (HSA) nanosystems were fabricated by modified nanoparticle albumin-bound technology. Cis-aconityl-PEG-maleimide (CA), an acid-labile linker, was used to conjugate D@HSA and CD47; the resultant CD47-CA@D@HSA exhibited tumor-specificity through receptor targeting, as well as preferential cleavage and drug release in the acidic tumor microenvironment (pH 5) compared to normal physiological pH conditions (pH 6.5, 7.4). The successful preparation of nanosized (∼220 nm), narrowly dispersed (∼0.13) CD47-CA@D@HSA was proven by physicochemical characterization. In vitro and in vivo internalization, accumulation, cytotoxicity, and apoptosis were observed to be higher with CD47-conjugated nanoconstructs, than with free D or non-targeted nanoconstructs. CD47-CA@D@HSA was found to promote the infiltration of cytotoxic T cells and tumor-associated macrophages into tumors and improve in vivo tumor inhibition. Administration in combination with PD-1 further improved antitumor efficacy by promoting immune responses that blocked the immune checkpoint. No signs of toxicity were seen in mice treated with the nanoconstructs; the formulation was, therefore, thought to be biocompatible and as having potential for clinical use. The targeted chemoimmunomodulation achieved by this combination therapy was found to combat major immunosuppressive facets, making it a viable candidate for use in the treatment of cancer.

Combination chemotherapeutic and immune-therapeutic anticancer approach via anti-PD-L1 antibody conjugated albumin nanoparticles

Anticancer regimens have been substantially enriched through monoclonal antibodies targeting immune checkpoints, programmed cell death-1/programmed cell death-ligand 1 (PD-L1) and cytotoxic T-lymphocyte antigen-4. Inconsistent clinical efficacy after solo immunotherapy may be compensated by nanotechnology-driven combination therapy. We loaded human serum albumin (HSA) nanoparticles with paclitaxel (PTX) via nanoparticle albumin-bound technology and pooled them with anti-PD-L1 monoclonal antibody through a pH-sensitive linker for targeting and immune response activation. Our tests demonstrated satisfactory preparation of paclitaxel-loaded, PD-L1-targeted albumin nanoparticles (PD-L1/PTX@HSA). They had small particle size (~200 nm) and polydispersity index (~0.12) and successfully incorporated each constituent. Relative to normal physiological pH, the formulation exhibited higher drug-release profiles favoring cancer cell-targeted release at low pH. Modifying nanoparticles with programmed cell death-ligand 1 increased cancer cell internalization in vitro and tumor accumulation in vivo in comparison with non-PD-L1-modified nanoparticles. PD-L1/PTX@HSA constructed by nanoparticle albumin-bound technology displayed successful tumor inhibition efficacy both in vitro and in vivo. There was successful effector T-cell infiltration, immunosuppressive programmed cell death-ligand 1, and regulatory T-cell suppression because of cytotoxic T-lymphocyte antigen-4 synergy. Moreover, PD-L1/PTX@HSA had low organ toxicity. Hence, the anti-tumor immune responses of PD-L1/PTX@HSA combined with chemotherapy and cytotoxic T-lymphocyte antigen-4 is a potential anti-tumor strategy for improving quantitative and qualitative clinical efficacy.