Cisplatin nanoparticles boost abscopal effect of radiation plus anti-PD1 therapy

Clinical application of immunogenic cell death inducers in cancer immunotherapy: turning cold tumors hot

Immunotherapy has emerged as a promising cancer treatment option in recent years. In immune "hot" tumors, characterized by abundant immune cell infiltration, immunotherapy can improve patients' prognosis by activating the function of immune cells. By contrast, immune "cold" tumors are often less sensitive to immunotherapy owing to low immunogenicity of tumor cells, an immune inhibitory tumor microenvironment, and a series of immune-escape mechanisms. Immunogenic cell death (ICD) is a promising cellular process to facilitate the transformation of immune "cold" tumors to immune "hot" tumors by eliciting innate and adaptive immune responses through the release of (or exposure to) damage-related molecular patterns. Accumulating evidence suggests that various traditional therapies can induce ICD, including chemotherapy, targeted therapy, radiotherapy, and photodynamic therapy. In this review, we summarize the biological mechanisms and hallmarks of ICD and introduce some newly discovered and technologically innovative inducers that activate the immune system at the molecular level. Furthermore, we also discuss the clinical applications of combing ICD inducers with cancer immunotherapy. This review will provide valuable insights into the future development of ICD-related combination therapeutics and potential management for "cold" tumors.

Application of nano-radiosensitizers in non-small cell lung cancer

Radiotherapy stands as a cornerstone in the treatment of numerous malignant tumors, including non-small cell lung cancer. However, the critical challenge of amplifying the tumoricidal effectiveness of radiotherapy while minimizing collateral damage to healthy tissues remains an area of significant research interest. Radiosensitizers, by methods such as amplifying DNA damage and fostering the creation of free radicals, play a pivotal role in enhancing the destructive impact of radiotherapy on tumors. Over recent decades, nano-dimensional radiosensitizers have emerged as a notable advancement. Their mechanisms include cell cycle arrest in the G2/M phase, combating tumor hypoxia, and others, thereby enhancing the efficacy of radiotherapy. This review delves into the evolving landscape of nanomaterials used for radiosensitization in non-small cell lung cancer. It provides insights into the current research progress and critically examines the challenges and future prospects within this burgeoning field.

The diverse effects of cisplatin on tumor microenvironment: Insights and challenges for the delivery of cisplatin by nanoparticles

Cisplatin is a well-known platinum-based chemotherapy medication that is widely utilized for some malignancies. Despite the direct cytotoxic consequences of cisplatin on tumor cells, studies in the recent decade have revealed that cisplatin can also affect different cells and their secretions in the tumor microenvironment (TME). Cisplatin has complex impacts on the TME, which may contribute to its anti-tumor activity or drug resistance mechanisms. These regulatory effects of cisplatin play a paramount function in tumor growth, invasion, and metastasis. This paper aims to review the diverse impacts of cisplatin and nanoparticles loaded with cisplatin on cancer cells and also non-cancerous cells in TME. The impacts of cisplatin on immune cells, tumor stroma, cancer cells, and also hypoxia will be discussed in the current review. Furthermore, we emphasize the challenges and prospects of using cisplatin in combination with other adjuvants and therapeutic modalities that target TME. We also discuss the potential synergistic effects of cisplatin with immune checkpoint inhibitors (ICIs) and other agents with anticancer potentials such as polyphenols and photosensitizers. Furthermore, the potential of nanoparticles for targeting TME and better delivery of cisplatin into tumors will be discussed.

Stromal and tumor immune microenvironment reprogramming through multifunctional cisplatin-based liposomes boosts the efficacy of anti-PD-1 immunotherapy in pancreatic cancer

The dense stromal barrier in pancreatic cancer tissues blocks intratumoral delivery and distribution of chemotherapeutics and therapeutic antibodies, causing poor chemoimmunotherapy responses. We designed a multi-targeted pH-sensitive liposome which encapsulates cisplatin (Pt) in its water core (denoted as ATF@Pt Lps) and shows high affinity for uPAR receptors in pancreatic cancer cells, tumor-associated macrophages, and cancer-associated fibroblasts. Systemic administration of ATF@Pt Lps enabled overcoming the central stromal cellular barrier and effective drug delivery into tumor cells, resulting in a strong therapeutic response in a Panc02 cell derived transplanted tumor mouse model. More importantly, ATF@Pt Lps degradation of collagen contributes to the infiltration of CD8+ T cells into tumors as well as an enhanced accumulation of anti PD-1 monoclonal antibodies. Furthermore, the killing of tumor cells by Pt also leads to the release of tumor antigens, which promote the proliferation of immune cells, especially CD83+ cells, Th1 CD4+ cells, and CD8+ cytotoxic T cells, that converted an immunoscore "cold" pancreatic cancer into a pro-immune "hot" tumor. A further combination with an immune checkpoint agent, anti PD-1 antibodies that inhibit PD-1, can enhance tumor specific cytotoxic T cell response. Accordingly, ATF@Pt Lps displays multi-targeting, controlled drug release, stromal disruption, enhanced penetration, killing of cancer cells, modification of the immunosuppressive microenvironment, and enhancement of immunity. This study provides important mechanistic information for the further development of a combination of ATF@Pt Lps and anti PD-1 antibodies for the effective treatment of pancreatic cancer.

Nanoparticle-based drug delivery systems to enhance cancer immunotherapy in solid tumors

Immunotherapy has developed rapidly in solid tumors, especially in the areas of blocking inhibitory immune checkpoints and adoptive T-cell transfer for immune regulation. Many patients benefit from immunotherapy. However, the response rate of immunotherapy in the overall population are relatively low, which depends on the characteristics of the tumor and individualized patient differences. Moreover, the occurrence of drug resistance and adverse reactions largely limit the development of immunotherapy. Recently, the emergence of nanodrug delivery systems (NDDS) seems to improve the efficacy of immunotherapy by encapsulating drug carriers in nanoparticles to precisely reach the tumor site with high stability and biocompatibility, prolonging the drug cycle of action and greatly reducing the occurrence of toxic side effects. In this paper, we mainly review the advantages of NDDS and the mechanisms that enhance conventional immunotherapy in solid tumors, and summarize the recent advances in NDDS-based therapeutic strategies, which will provide valuable ideas for the development of novel tumor immunotherapy regimen.

Nanomedicine-based adjuvant therapy: a promising solution for lung cancer

Lung cancer has been the leading cause of cancer-related deaths worldwide for decades. Despite the increasing understanding of the underlying disease mechanisms, the prognosis still remains poor for many patients. Novel adjuvant therapies have emerged as a promising treatment method to augment conventional methods and boost the therapeutic effects of primary therapies. Adjuvant therapy based on nanomedicine has gained considerable interest for supporting and enhancing traditional therapies, such as chemotherapy, immunotherapy, and radiotherapy, due to the tunable physicochemical features and ease of synthetic design of nanomaterials. In addition, nanomedicine can provide protective effects against other therapies by reducing adverse side effects through precise disease targeting. Therefore, nanomedicine-based adjuvant therapies have been extensively employed in a wide range of preclinical and clinical cancer treatments to overcome the drawbacks of conventional therapies. In this review, we mainly discuss the recent advances in adjuvant nanomedicine for lung cancer treatment and highlight their functions in improving the therapeutic outcome of other therapies, which may inspire new ideas for advanced lung cancer therapies and stimulate research efforts around this topic.

Abscopal Effect, Extracellular Vesicles and Their Immunotherapeutic Potential in Cancer Treatment

The communication between tumor cells and the microenvironment plays a fundamental role in the development, growth and further immune escape of the tumor. This communication is partially regulated by extracellular vesicles which can direct the behavior of surrounding cells. In recent years, it has been proposed that this feature could be applied as a potential treatment against cancer, since several studies have shown that tumors treated with radiotherapy can elicit a strong enough immune response to eliminate distant metastasis; this phenomenon is called the abscopal effect. The mechanism behind this effect may include the release of extracellular vesicles loaded with damage-associated molecular patterns and tumor-derived antigens which activates an antigen-specific immune response. This review will focus on the recent discoveries in cancer cell communications via extracellular vesicles and their implication in tumor development, as well as their potential use as an immunotherapeutic treatment against cancer.

Cisplatin and Albumin-Based Gold-Cisplatin Nanoparticles Enhance Ablative Radiation Therapy-Induced Antitumor Immunity in Local and Distant Tumor Microenvironment

PURPOSE

Ablative radiation therapy (RT) is an important strategy to eliminate primary tumor and can potentially induce the abscopal effect. Human serum albumin nanoparticle (NP) was used for controlled release of cisplatin to decrease cisplatin's systemic toxicity, and gold (Au) was added to increase RT-induced immunogenic cell death and potentiate the abscopal antitumor immunity.

METHODS AND MATERIALS

The designed albumin-based cisplatin-conjugated AuNPs were administered concurrently with ablative RT. C57BL/6 mice implanted with syngeneic murine Lewis lung carcinoma or murine MB49 tumor models were treated with ablative RT (12 Gy per fraction for 2 fractions, total 24 Gy), cisplatin, or Au-cisplatin NPs.

RESULTS

Combining ablative RT with cisplatin or Au-cisplatin NPs both destroyed the primary tumor effectively and elicited immunogenic cell death accompanied by release of danger-associated molecular patterns. This enhanced recruitment of effector tumor-infiltrating immune cells, including natural killer T cells and CD8+ T cells, and elicited an increased percentage of professional antigen-presenting CD11c+ dendritic cells. Transient weight loss, accompanying hepatotoxicity, nephrotoxicity, and hematopoietic suppression, was observed as a systemic adverse event in the cisplatin but not the Au-cisplatin NPs group. Cisplatin and Au-cisplatin NPs both showed equivalent ability to reduce metastatic potential when combined with ablative RT, confirmed by suppressed unirradiated flank tumor growth and decreased metastatic lung tumor burden, which translated to improved survival. Mobilization and abundance of effector tumor-infiltrating immune cells including CD8+ T cells and dendritic cells were observed in the distant lung tumor microenvironment after ablative RT with cisplatin or Au-cisplatin NPs, demonstrating increased antitumor immunotherapeutic activity as an abscopal effect.

CONCLUSIONS

Compared with cisplatin, the albumin-based Au-cisplatin NPs exhibited equivalent but no superior antitumor immunotherapeutic activity while reducing systemic adverse events and can be safely administered concurrently with ablative RT. Alternative NP formulations may be designed to further improve anticancer outcomes.

Nanomedicine embraces cancer radio-immunotherapy: mechanism, design, recent advances, and clinical translation

Cancer radio-immunotherapy, integrating external/internal radiation therapy with immuno-oncology treatments, emerges in the current management of cancer. A growing number of pre-clinical studies and clinical trials have recently validated the synergistic antitumor effect of radio-immunotherapy, far beyond the "abscopal effect", but it suffers from a low response rate and toxicity issues. To this end, nanomedicines with an optimized design have been introduced to improve cancer radio-immunotherapy. Specifically, these nanomedicines are elegantly prepared by incorporating tumor antigens, immuno- or radio-regulators, or biomarker-specific imaging agents into the corresponding optimized nanoformulations. Moreover, they contribute to inducing various biological effects, such as generating in situ vaccination, promoting immunogenic cell death, overcoming radiation resistance, reversing immunosuppression, as well as pre-stratifying patients and assessing therapeutic response or therapy-induced toxicity. Overall, this review aims to provide a comprehensive landscape of nanomedicine-assisted radio-immunotherapy. The underlying working principles and the corresponding design strategies for these nanomedicines are elaborated by following the concept of "from bench to clinic". Their state-of-the-art applications, concerns over their clinical translation, along with perspectives are covered.

From targeted therapy to a novel way: Immunogenic cell death in lung cancer

Lung cancer (LC) is one of the most incident malignancies and a leading cause of cancer mortality worldwide. Common tumorigenic drivers of LC mainly include genetic alterations of EGFR, ALK, KRAS, BRAF, ROS1, and MET. Small inhibitory molecules and antibodies selectively targeting these alterations or/and their downstream signaling pathways have been approved for treatment of LC. Unfortunately, following initial positive responses to these targeted therapies, a large number of patients show dismal prognosis due to the occurrence of resistance mechanisms, such as novel mutations of these genes and activation of alternative signaling pathways. Over the past decade, it has become clear that there is no possible cure for LC unless potent antitumor immune responses are induced by therapeutic intervention. Immunogenic cell death (ICD) is a newly emerged concept, a form of regulated cell death that is sufficient to activate adaptive immune responses against tumor cells. It transforms dying cancer cells into a therapeutic vaccine and stimulates long-lasting protective antitumor immunity. In this review, we discuss the key targetable genetic aberrations and the underlying mechanism of ICD in LC. Various agents inducing ICD are summarized and the possibility of harnessing ICD in LC immunotherapy is further explored.

Renal Proximal Tubular Cells: A New Site for Targeted Delivery Therapy of Diabetic Kidney Disease

Diabetic kidney disease (DKD) is a major complication of diabetes mellitus (DM) and the leading cause of end-stage kidney disease (ESKD) worldwide. A significant number of drugs have been clinically investigated for the treatment of DKD. However, a large proportion of patients still develop end-stage kidney disease unstoppably. As a result, new effective therapies are urgently needed to slow down the progression of DKD. Recently, there is increasing evidence that targeted drug delivery strategies such as large molecule carriers, small molecule prodrugs, and nanoparticles can improve drug efficacy and reduce adverse side effects. There is no doubt that targeted drug delivery strategies have epoch-making significance and great application prospects for the treatment of DKD. In addition, the proximal tubule plays a very critical role in the progression of DKD. Consequently, the purpose of this paper is to summarize the current understanding of proximal tubule cell-targeted therapy, screen for optimal targeting strategies, and find new therapeutic approaches for the treatment of DKD.

Engineered nanomaterials trigger abscopal effect in immunotherapy of metastatic cancers

Despite advances in cancer treatment, metastatic cancer is still the main cause of death in cancer patients. At present, the treatment of metastatic cancer is limited to palliative care. The abscopal effect is a rare phenomenon in which shrinkage of metastatic tumors occurs simultaneously with the shrinkage of a tumor receiving localized treatment, such as local radiotherapy or immunotherapy. Immunotherapy shows promise for cancer treatment, but it also leads to consequences such as low responsiveness and immune-related adverse events. As a promising target-based approach, intravenous or intratumoral injection of nanomaterials provides new opportunities for improving cancer immunotherapy. Chemically modified nanomaterials may be able to trigger the abscopal effect by regulating immune cells. This review discusses the use of nanomaterials in killing metastatic tumor cells through the regulation of immune cells and the prospects of such nanomaterials for clinical use.

Radiotherapy combined with immunotherapy: the dawn of cancer treatment

Radiotherapy (RT) is delivered for purposes of local control, but can also exert systemic effect on remote and non-irradiated tumor deposits, which is called abscopal effect. The view of RT as a simple local treatment has dramatically changed in recent years, and it is now widely accepted that RT can provoke a systemic immune response which gives a strong rationale for the combination of RT and immunotherapy (iRT). Nevertheless, several points remain to be addressed such as the interaction of RT and immune system, the identification of the best schedules for combination with immunotherapy (IO), the expansion of abscopal effect and the mechanism to amplify iRT. To answer these crucial questions, we roundly summarize underlying rationale showing the whole immune landscape in RT and clinical trials to attempt to identify the best schedules of iRT. In consideration of the rarity of abscopal effect, we propose that the occurrence of abscopal effect induced by radiation can be promoted to 100% in view of molecular and genetic level. Furthermore, the “radscopal effect” which refers to using low-dose radiation to reprogram the tumor microenvironment may amplify the occurrence of abscopal effect and overcome the resistance of iRT. Taken together, RT could be regarded as a trigger of systemic antitumor immune response, and with the help of IO can be used as a radical and systemic treatment and be added into current standard regimen of patients with metastatic cancer.

Cisplatin Nanoparticles Promote Intratumoral CD8+ T Cell Priming via Antigen Presentation and T Cell Receptor Crosstalk

Nanomedicines are highly promising for cancer therapy due to their minimal side effects. However, little is known regarding their host immune response, which may limit their clinical efficacy and applications. Here, we find that cisplatin (CDDP)-loaded poly(l-glutamic acid)-graft-methoxy poly(ethylene glycol) complex nanoparticles (CDDP-NPs) elicit a strong antitumor CD8⁺ T cell-mediated immune response in a tumor-bearing mouse model compared to free CDDP. Mechanistically, the sustained retention of CDDP-NPs results in persistent tumor MHC-I overexpression, which promotes the formation of MHC-I-antigen peptide complex (pMHC-I), enhances the interaction between pMHC-I and T cell receptor (TCR), and leads to the activation of TCR signaling pathway and CD8⁺ T cell-mediated immune response. Furthermore, CDDP-NPs upregulate the costimulatory OX40 on intratumoral CD8⁺ T cells, and synergize with the agonistic OX40 antibody (aOX40) to suppress tumor growth by 89.2%. Our study provides a basis for the efficacy advantage of CDDP-based nanomedicines and immunotherapy.

Targeting the PD-1/PD-L1 axis for cancer treatment: a review on nanotechnology

Although nanomedicines have been in the oncology field for almost three decades with the introduction of doxil, only a few nanomedicine products have reached approval. Can nanotechnology be a realistic tool to reduce the number of hospital beds? At present, several clinically approved anti-PD-1/PD-L1 antibodies or CAR T cell-based therapies are available; however, the immunotherapy field is far from mature. Will immunotherapy be the fourth pillar of cancer treatment? In this review, we summarized the current status of immunotherapy using PD-1/PD-L1-targeting nanocarriers. The knowledge on material science, therapeutic agents and formulation designs could pave the way for high-efficacy treatment outcomes.

Stimuli-Responsive Nanoparticles for Controlled Drug Delivery in Synergistic Cancer Immunotherapy

Cancer immunotherapy has achieved promising clinical progress over the recent years for its potential to treat metastatic tumors and inhibit their recurrences effectively. However, low patient response rates and dose-limiting toxicity remain as major dilemmas for immunotherapy. Stimuli-responsive nanoparticles (srNPs) combined with immunotherapy offer the possibility to amplify anti-tumor immune responses, where the weak acidity, high concentration of glutathione, overexpressions of enzymes, and reactive oxygen species, and external stimuli in tumors act as triggers for controlled drug release. This review highlights the design of srNPs based on tumor microenvironment and/or external stimuli to combine with different anti-tumor drugs, especially the immunoregulatory agents, which eventually realize synergistic immunotherapy of malignant primary or metastatic tumors and acquire a long-term immune memory to prevent tumor recurrence. The authors hope that this review can provide theoretical guidance for the construction and clinical transformation of smart srNPs for controlled drug delivery in synergistic cancer immunotherapy.

Development of nanotechnology-mediated precision radiotherapy for anti-metastasis and radioprotection

Radiotherapy (RT), including external beam RT and internal radiation therapy, uses high-energy ionizing radiation to kill tumor cells.