A bio-responsive, cargo-catchable gel for postsurgical tumor treatment via ICD-based immunotherapy

Advances in cancer diagnosis and therapy by alginate-based multifunctional hydrogels: A review

The field of oncology has been changed by the application of hydrogels. These 3D polymeric networks have demonstrated significant promise in the treatment of cancer and can boost the efficacy of conventional therapeutics including chemotherapy and immunotherapy. Noteworthy, the development of biocompatible and effective hydrogels has been of interest. In this case, alginate as a biopolymer and carbohydrate polymer has been used to modify or synthesis multifunctional nanoparticles for the treatment of human diseases, especially cancer. Therefore, highlighting the function of alginate in the development of hydrogels in cancer therapy can provide new insights for improving outcome and survival rate of patients. Alginate hydrogels improve the specific and selective delivery of cargo and therefore, they reduce the systemic toxicity of drugs, while they enhance anti-cancer activity. Alginate hydrogels protect the genes against degradation by enzymes and increase blood circulation time. The alginate hydrogels can respond to the specific stimuli in the tumor microenvironment including pH, redox and light to improve the site-specific release of cargo. The nanoparticles can be incorporated in the structure of alginate hydrogels to augment their anti-cancer activity. In addition, alginate hydrogels can accelerate immunotherapy and phototherapy through delivery of immunomodulators and photosensitizers, respectively.

Reprogramming cellular senescence in the tumor microenvironment augments cancer immunotherapy through multifunctional nanocrystals

Harnessing the immunogenic potential of senescent tumor cells provides an opportunity to remodel tumor microenvironment (TME) and boost antitumor immunity. However, this potential needs to be sophisticatedly wielded to avoid additional immunosuppressive capacity of senescent cells. Our study shows that blocking the JAK2/STAT3 pathway enhances immunogenic efficacy of Aurora kinase inhibitor alisertib (Ali)-induced senescence by reducing immunosuppressive senescence-associated secretory phenotype (SASP) while preserving immunogenic SASP. Hypothesizing that SASP reprogramming with Ali and JAK2 inhibitor ruxolitinib (Rux) will benefit cancer immunotherapy, we create nanoparticulate crystals (Ali-Rux) composed of Ali and Rux with a fully active pharmaceutical ingredient. Immunization with Ali-Rux-orchestrated senescent cells promotes stronger activation of antigen-presenting cells, enhancing antitumor immune surveillance. This approach remodels the TME by increasing CD8+ T cell and NK recruitment and activation while decreasing MDSCs. Combined with PD-L1 blockade, Ali-Rux elicits a durable antitumor immune response, suggesting the TME reshaping approach as a potential cancer immunotherapy.

Immunotherapy revolutionizing brain metastatic cancer treatment: personalized strategies for transformative outcomes

Brain metastatic cancer poses a significant clinical challenge, with limited treatment options and poor prognosis for patients. In recent years, immunotherapy has emerged as a promising strategy for addressing brain metastases, offering distinct advantages over conventional treatments. This review explores the evolving landscape of tumor immunotherapy in the context of brain metastatic cancer, focusing on the intricate interplay between the tumor microenvironment (TME) and immunotherapeutic approaches. By elucidating the complex interactions within the TME, including the role of immune cells, cytokines, and extracellular matrix components, this review highlights the potential of immunotherapy to reshape the treatment paradigm for brain metastases. Leveraging immune checkpoint inhibitors, cellular immunotherapies, and personalized treatment strategies, immunotherapy holds promise in overcoming the challenges posed by the blood-brain barrier and immunosuppressive microenvironment of brain metastases. Through a comprehensive analysis of current research findings and future directions, this review underscores the transformative impact of immunotherapy on the management of brain metastatic cancer, offering new insights and opportunities for personalized and precise therapeutic interventions.

Low-dose doxorubicin loaded extracellular vesicles combined Fas/FasL pathway-mediated chemo-sensitization and immunotherapy against tumor

The clinical application of doxorubicin (DOX) is mainly restricted by its serious side effects, poor drug delivery efficiency, and limited immunogenic death (ICD) effect. To improve DOX-based chemotherapy and ameliorate its adverse effects, we utilized 3LL cell-derived extracellular vesicles to encapsulate DOX and sodium nitroprusside (SNP) to obtain DOX/SNP@CM, which could effectively target the tumor site by harnessing the inherent homologous targeting property of tumor cell membranes. DOX performed its role on chemotherapy, and SNP successfully respond to the intracellular GSH to continuously generate nitric oxide (NO). The in situ-produced NO upregulated the Fas expression on the tumor cell surface, thereby sensitizing the Fas/FasL pathway-mediated tumor cell apoptosis of DOX. Furthermore, NO also boosted the intratumoral infiltration of cytotoxic T cells by promoted ICD effect towards tumor cells. Importantly, the anti-tumor immunity tightly cooperated with Fas/FasL mediated tumor cell apoptosis by NO-mediated manipulation on Fas/FasL interaction, collectively making DOX/SNP@CM exert significant tumor growth inhibition with low-dose DOX. Remarkably, DOX and SNP both are widely used clinical medicines, ensuring DOX/SNP@CM a potential opportunity for future practical applications.

Boosting Checkpoint Immunotherapy with Biomimetic Nanodrug Delivery Systems

Immune checkpoint blockade (ICB) has achieved unprecedented progress in tumor immunotherapy by blocking specific immune checkpoint molecules. However, the high biodistribution of the drug prevents it from specifically targeting tumor tissues, leading to immune-related adverse events. Biomimetic nanodrug delivery systems (BNDSs) readily applicable to ICB therapy have been widely developed at the preclinical stage to avoid immune-related adverse events. By exploiting or mimicking complex biological structures, the constructed BNDS as a novel drug delivery system has good biocompatibility and certain tumor-targeting properties. Herein, the latest findings regarding the aforementioned therapies associated with ICB therapy are highlighted. Simultaneously, prospective bioinspired engineering strategies can be designed to overcome the four-level barriers to drug entry into lesion sites. In future clinical translation, BNDS-based ICB combination therapy represents a promising avenue for cancer treatment.

Amplifying "eat me signal" by immunogenic cell death for potentiating cancer immunotherapy

Immunogenic cell death (ICD) is a unique mode of cell death, which can release immunogenic damage-associated molecular patterns (DAMPs) and tumor-associated antigens to trigger long-term protective antitumor immune responses. Thus, amplifying "eat me signal" during tumor ICD cascade is critical for cancer immunotherapy. Some therapies (radiotherapy, photodynamic therapy (PDT), photothermal therapy (PTT), etc.) and inducers (chemotherapeutic agents, etc.) have enabled to initiate and/or facilitate ICD and activate antitumor immune responses. Recently, nanostructure-based drug delivery systems have been synthesized for inducing ICD through combining treatment of chemotherapeutic agents, photosensitizers for PDT, photothermal transformation agents for PTT, radiosensitizers for radiotherapy, etc., which can release loaded agents at an appropriate dosage in the designated place at the appropriate time, contributing to higher efficiency and lower toxicity. Also, immunotherapeutic agents in combination with nanostructure-based drug delivery systems can produce synergetic antitumor effects, thus potentiating immunotherapy. Overall, our review outlines the emerging ICD inducers, and nanostructure drug delivery systems loading diverse agents to evoke ICD through chemoradiotherapy, PDT, and PTT or combining immunotherapeutic agents. Moreover, we discuss the prospects and challenges of harnessing ICD induction-based immunotherapy, and highlight the significance of multidisciplinary and interprofessional collaboration to promote the optimal translation of this treatment strategy.

Promoting the Recruitment, Engagement, and Reinvigoration of Effector T Cells via an Injectable Hydrogel with a Supramolecular Binding Capability for Cancer Immunotherapy

T cells play a basic and key role in immunotherapy against solid tumors, and efficiently recruiting them into neoplastic foci and sustaining long-term effector function are consistent goals that remain a critical challenge. Here, an injectable alginate-based hydrogel with abundant β-cyclodextrin (ALG-βCD) sites is developed and intratumorally injected to recruit CCR9+ CD8+ T cells (a subset of T cells with robust antitumor activity) via the trapped chemokine CCL25. In the meantime, an intravenously injected adamantane-decorated anti-PD1 antibody (Ad-aPD1) would hitchhike on recruited CCR9+ CD8+ T cells to achieve the improved intratumoral accumulation of Ad-aPD1. Moreover, the Ad-PD1 and Ad-PDL1 antibodies are immobilized in the ALG-βCD hydrogel through supramolecular host-guest interactions of Ad and βCD, which facilitate engagement between CD8+ T cells and tumor cells and reinvigorate CD8+ T cells to avoid exhaustion. Based on this treatment strategy, T cell-mediated anticancer activity is promoted at multiple levels, eventually achieving superior antitumor efficacy in both orthotopic and postsurgical B16-F10 tumor models.

Advances in immunotherapy for triple-negative breast cancer

BACKGROUND

Immunotherapy has recently emerged as a treatment strategy which stimulates the human immune system to kill tumor cells. Tumor immunotherapy is based on immune editing, which enhances the antigenicity of tumor cells and increases the tumoricidal effect of immune cells. It also suppresses immunosuppressive molecules, activates or restores immune system function, enhances anti-tumor immune responses, and inhibits the growth f tumor cell. This offers the possibility of reducing mortality in triple-negative breast cancer (TNBC).

MAIN BODY

Immunotherapy approaches for TNBC have been diversified in recent years, with breakthroughs in the treatment of this entity. Research on immune checkpoint inhibitors (ICIs) has made it possible to identify different molecular subtypes and formulate individualized immunotherapy schedules. This review highlights the unique tumor microenvironment of TNBC and integrates and analyzes the advances in ICI therapy. It also discusses strategies for the combination of ICIs with chemotherapy, radiation therapy, targeted therapy, and emerging treatment methods such as nanotechnology, ribonucleic acid vaccines, and gene therapy. Currently, numerous ongoing or completed clinical trials are exploring the utilization of immunotherapy in conjunction with existing treatment modalities for TNBC. The objective of these investigations is to assess the effectiveness of various combined immunotherapy approaches and determine the most effective treatment regimens for patients with TNBC.

CONCLUSION

This review provides insights into the approaches used to overcome drug resistance in immunotherapy, and explores the directions of immunotherapy development in the treatment of TNBC.

Lysyl oxidase-responsive anchoring nanoparticles for modulation of the tumor immune microenvironment

In the tumor microenvironment, lysyl oxidase (LOX) is known to play a key role in stabilizing the tumor extracellular matrix. Here, we designed LOX-responsive nanoparticles to interact with the collagen matrix of the tumor microenvironment. Collagen-coated and imiquimod-loaded polydopamine nanoparticles (CPN/IQ) could form crosslinked structures with the collagen matrix via LOX. In vitro, anchoring of CPN/IQ nanoparticles was observed with LOX-secreting CT26 cells, but this was blocked by a LOX inhibitor. In CT26 tumor-bearing mice, co-administration of nanoparticles plus the LOX inhibitor did not significantly alter the antitumor efficacy among nanoparticles. In the absence of the LOX inhibitor, however, a single administration of CPN/IQ could provide sustained responsiveness to near-infrared irradiation and ablation of primary tumors. In the primary tumor microenvironment, CPN/IQ lowered the Treg cell population but increased the cytotoxic CD3+CD8+ T cell population. In splenic dendritic cells, CPN/IQ treatment significantly increased the CD11c+CD86+ and CD11c+CD80+ cell populations. In a CT26 distant tumor-rechallenge model, CPN/IQ treatment increased the cytotoxic CD3+CD8+ T cell population and provided 100% survival of mice until 64 days. This study indicates the feasibility of tumor immune microenvironment modulation using LOX-responsive size-transforming nanoparticles. Although we tested the concept in a CT26 cell-derived tumor model, the concept of LOX-responsive collagen matrix- anchoring nanoparticles may be broadly applied to other tumor tissues with LOX-rich tumor microenvironments.

Engineered cell-based therapies in ex vivo ready-made CellDex capsules have therapeutic efficacy in solid tumors

Encapsulated cell-based therapies for solid tumors have shown promising results in pre-clinical settings. However, the inability to culture encapsulated therapeutic cells prior to their transplantation has limited their translation into clinical settings. In this study, we created a wide variety of engineered therapeutic cells (ThC) loaded in micropore-forming gelatin methacryloyl (GelMA) hydrogel (CellDex) capsules that can be cultured in vitro prior to their transplantation in surgically debulked solid tumors. We show that both allogeneic and autologous engineered cells, such as stem cells (SCs), macrophages, NK cells, and T cells, proliferate within CellDex capsules and migrate out of the gel in vitro and in vivo. Furthermore, tumor cell specific therapeutic proteins and oncolytic viruses released from CellDex capsules retain and prolong their anti-tumor effects. In vivo, ThCs in pre-manufactured Celldex capsules persist long-term and track tumor cells. Moreover, chimeric antigen receptor (CAR) T cell bearing CellDex (T-CellDex) and human SC releasing therapeutic proteins (hSC-CellDex) capsules show therapeutic efficacy in metastatic and primary brain tumor resection models that mimic standard of care of tumor resection in patients. Overall, this unique approach of pre-manufactured micropore-forming CellDex capsules offers an effective off-the-shelf clinically viable strategy to treat solid tumors locally.

KCl Nanoparticles as Potential Inducer of Immunogenic Cell Death for Cancer Immunotherapy

Immunogenic cell death (ICD) is a promising cancer immunotherapy by inducing antigen-presenting cell maturation. Many inorganic nanomodulators have been developed for cancer therapy via ion overload, and their ICD-inducing properties have also been explored for immunotherapy. Here, we report a potassium chloride nanoparticle (PCNP)-loaded poly(lactic-co-glycolic acid) nanoparticle coated with cancer cell membrane (PC@P-CCM) for cancer therapy. Through cancer cell membrane (CCM)-achieved surface functionalization, the homotypic targeting behaviors of PC@P-CCM are dramatically enhanced. Once internalized by cancer cells, the PC@P-CCM could be degraded in acidic lysosomes, thus releasing K⁺ and Cl^- ions. These ions can change the osmotic pressure of cancer cells, causing a hypertonic state in the cancer cells in a short time and leading to the rupture and death of cancer cells. Furthermore, these ions can stimulate cancer cells to secrete adenosine triphosphate (ATP) and high mobility group box 1 (HMGB-1); meanwhile, calreticulin (CRT) showed increased presentation on the surface of cancer cells, which can further induce dendritic cell maturation and promote the immunotherapy. This work provides a new perspective on KCl nanoparticle-based cancer immunotherapy.

Charge reversal yolk-shell liposome co-loaded JQ1 and doxorubicin with high drug loading and optimal ratio for synergistically enhanced tumor chemo-immunotherapy via blockade PD-L1 pathway

Antitumor immunotherapy has become a powerful therapeutic modality to identify and kill various malignant tumors by harnessing the immune system. However, it is hampered by the immunosuppressive microenvironment and poor immunogenicity in malignant tumors. Herein, in order to achieve multi-loading of drugs with different pharmacokinetic properties and targets, a charge reversal yolk-shell liposome co-loaded with JQ1 and doxorubicin (DOX) into the poly (D,L-lactic-co-glycolic acid) (PLGA) yolk and the lumen of the liposome respectively was engineered to increase hydrophobic drug loading capacity and stability under physiological conditions and further enhance tumor chemotherapy via blockade programmed death ligand 1 (PD-L1) pathway. This nanoplatform could release less JQ1 compared to traditional liposomes to avoid drug leakage under physiological conditions due to the protection of liposomes on JQ1 loaded PLGA nanoparticles while the release of JQ1 increased in an acidic environment. In the tumor microenvironment, released DOX promoted immunogenic cell death (ICD), and JQ1 blocked the PD-L1 pathway to strengthen chemo-immunotherapy. The in vivo antitumor results demonstrated the collaborative treatment of DOX and JQ1 in B16-F10 tumor-bearing mice models with minimized systemic toxicity. Furthermore, the orchestrated yolk-shell nanoparticle system could enhance the ICD effect, caspase 3 activation, and cytotoxic T lymphocyte infiltration while inhibiting PD-L1 expression, provoking a strong antitumor effect, whereas yolk-shell liposomes encapsulating only JQ1 or DOX showed modest tumor therapeutic effects. Hence, the cooperative yolk-shell liposome strategy provides a potential candidate for enhancement of hydrophobic drug loading and stability, showing potential for clinic application and synergistic cancer chemo-immunotherapy.

Polysaccharide-based nanocarriers for efficient transvascular drug delivery

Polysaccharide-based nanocarriers (PBNs) are the focus of extensive investigation because of their biocompatibility, low cost, wide availability, and chemical versatility, which allow a wide range of anticancer agents to be loaded within the nanocarriers. Similar to other nanocarriers, most PBNs are designed to extravasate out of tumor vessels, depending on the enhanced permeability and retention (EPR) effect. However, the EPR effect is compromised in some tumors due to the heterogeneity of tumor structures. Transvascular transport efficacy is decreased by complex blood vessels and condensed tumor stroma. The limited extravasation impedes efficient drug delivery into tumor parenchyma, and thus affects the subsequent tumor accumulation, which hinders the therapeutic effect of PBNs. Therefore, overcoming the biological barriers that restrict extravasation from tumor vessels is of great importance in PBN design. Many strategies have been developed to enhance the EPR effect that involve nanocarrier property regulation and tumor structure remodeling. Moreover, some researchers have proposed active transcytosis pathways that are complementary to the paracellular EPR effect to increase the transvascular extravasation efficiency of PBNs. In this review, we summarize the recent advances in the design of PBNs with enhanced transvascular transport to enable optimization of PBNs in the extravasation of the drug delivery process. We also discuss the obstacles and challenges that need to be addressed to clarify the transendothemial mechanism of PBNs and the potential interactions between extravasation and other drug delivery steps.

Nanotechnology-based approaches overcome lung cancer drug resistance through diagnosis and treatment

Lung cancer continues to be a malignant tumor with high mortality. Two obstacles interfere with curative therapy of lung cancer: (i) poor diagnosis at the early stages, as symptoms are not specific or asymptomatic; and (ii) invariably emerging drug resistance after treatment. Some factors contributing to drug resistance include preexisting genetic/genomic drug-resistant alteration(s); activation of adaptive drug resistance pathways; remodeling of the tumor microenvironment; and pharmacological mechanisms or activation of drug efflux pumps. Despite the mechanisms explored to better understand drug resistance, a gap remains between molecular understanding and clinical application. Therefore, facilitating the translation of basic science into the clinical setting is a great challenge. Nanomedicine has emerged as a promising tool for cancer treatment. Because of their excellent physicochemical properties and enhanced permeability and retention effects, nanoparticles have great potential to revolutionize conventional lung cancer diagnosis and combat drug resistance. Nanoplatforms can be designed as carriers to improve treatment efficacy and deliver multiple drugs in one system, facilitating combination treatment to overcome drug resistance. In this review, we describe the difficulties in lung cancer treatment and review recent research progress on nanoplatforms aimed at early diagnosis and lung cancer treatment. Finally, future perspectives and challenges of nanomedicine are also discussed.

Locoregional Lymphatic Delivery Systems Using Nanoparticles and Hydrogels for Anticancer Immunotherapy

The lymphatic system has gained significant interest as a target tissue to control cancer progress, which highlights its central role in adaptive immune response. Numerous mechanistic studies have revealed the benefits of nano-sized materials in the transport of various cargos to lymph nodes, overcoming barriers associated with lymphatic physiology. The potential of sustained drug delivery systems in improving the therapeutic index of various immune modulating agents is also being actively discussed. Herein, we aim to discuss design rationales and principles of locoregional lymphatic drug delivery systems for invigorating adaptive immune response for efficient antitumor immunotherapy and provide examples of various advanced nanoparticle- and hydrogel-based formulations.

Improvement of TNBC immune checkpoint blockade with a microwave-controlled ozone release nanosystem

Despite revolutionary achievements have been made in clinical cancer therapy, the immune checkpoint blockade regimen still presents limited efficacy on tumors lack of neoantigens exposure. Here, we designed and synthesized an on-demand microwave-controlled ozone release nanosystem to specifically generate reactive oxygen species in tumor mass. By taking advantage of iRGD modification, the synthesized nanosystem can be specifically enriched in the tumor microenvironment and subsequently internalized by tumor cells. Triggered by the low-power microwave, ozone was released from the nanocarriers and inhibited tumor cell growth in vitro and in vivo. Molecular mechanism investigation further unraveled that the released-ozone induced cytolytic cell death through the rapid generation of reactive oxygen species such as hydroxyl radical. The tumor-specific neoantigen derived from this immunogenic cell death promoted cytotoxic T-lymphocytes infiltration, which provided a fundament for immune checkpoint blockade therapy. In the triple-negative breast cancer animal model, tumor-specific delivery of ozone significantly improved the systematical anti-tumor efficacy of the PD-1 blockade antibody. Notably, tumor-locally confined microwave-controlled release avoided systematic toxicity in the tested animals. Collectively, our nanosystem provides a novel controllable strategy for promoting immune checkpoint blockade therapy, especially in tumor types deficient in infiltrated T-lymphocytes.

A supramolecular self-assembled nanomaterial for synergistic therapy of immunosuppressive tumor

Triple negative breast cancer (TNBC) is an immunosuppressive "cold" tumor that lacks immune cell infiltration and activation, resulting in a poor response to immune checkpoint blockade (ICB) therapies. In addition, TNBC is poorly responsive to targeted therapies due to the absence of efficient molecular targets. A strategy that can block molecular signal transduction, stimulate immunogenicity, and activate the immune response is a promising approach to achieve ideal clinical benefit. Herein, we designed and synthesized an aggregation-induced emission luminogen (AIEgen)-conjugated self-assembling peptide that targets epidermal growth factor receptor (EGFR), named TPA-FFG-LA. TPA-FFG-LA peptides form nanoassemblies on the surface of EGFR-positive TNBC cells and are internalized into cells through endocytosis, which inhibit EGFR signaling transduction and provoke lysosomal membrane permeabilization (LMP). Upon light irradiation, the aggregated AIEgens produce massive reactive oxygen species (ROS) to exacerbate LMP and trigger immunogenic cell death (ICD), resulting in elimination of residual EGFR-negative tumor cells and exerting long-term antitumor effects. The in vitro and in vivo experiments verified that TPA-FFG-LA nanoassemblies suppress tumor growth, provoke immune cell activation and infiltration, and cause EGFR degradation and LMP. These results suggest that the combination of supramolecular assembly induced molecular targeting effects and lysosome dysfunction with ICD-stimulated immune activation is a plausible strategy for the efficient therapy of immunosuppressive TNBC.

Sequentially sustained release of anticarcinogens for postsurgical chemoimmunotherapy

Postsurgical treatment is of great importance to combat tumor recurrence and metastasis. Anti-CD47 antibodies (aCD47) can block the CD47-signal regulatory protein-alpha (CD47-SIRPα) pathway to restore immunity. Here, an in-situ gel implantation was engineered by crosslinking chitosan (CS) and pullulan (Pul) for postsurgical treatment. A highly selected chemotherapeutic, cyclopamine (Cyc), encapsulated in liposomes (Cyc-Lip) was co-loaded with aCD47 in gels for chemoimmunotherapy. Importantly, a sequential drug release kinetics can be achieved. Nanotherapeutics were confirmed to be released prior to aCD47 in a burst-release manner, which was benefit for immediately killing residual tumor cells followed by releasing tumor antigens. Meanwhile, aCD47 was released in a sustained-release manner to restore macrophage functions and exert anti-tumor immune responses. Afterwards, the efficacy of in-situ chemoimmunotherapy was confirmed on 4T1 mouse breast cancer models, which could not only efficiently augment anti-tumor effect to inhibit tumor recurrence but also establish a long-term immune memory to combat tumor metastasis.

When Natural Compounds Meet Nanotechnology: Nature-Inspired Nanomedicines for Cancer Immunotherapy

Recent significant strides of natural compounds in immunomodulation have highlighted their great potential against cancer. Despite many attempts being made for cancer immunotherapy, the biomedical application of natural compounds encounters a bottleneck because of their unclear mechanisms, low solubility and bioavailability, and limited efficacy. Herein, we summarize the immune regulatory mechanisms of different natural compounds at each step of the cancer-immunity cycle and highlight their anti-tumor potential and current limitations. We then propose and present various drug delivery strategies based on nanotechnology, including traditional nanoparticles (NPs)-based delivery strategies (lipid-based NPs, micelles, and polysaccharide/peptide/protein-based NPs) and novel delivery strategies (cell-derived NPs and carrier-free NPs), thus providing solutions to break through existing bottlenecks. Furthermore, representative applications of nature-inspired nanomedicines are also emphasized in detail with the advantages and disadvantages discussed. Finally, the challenges and prospects of natural compounds for cancer immunotherapy are provided, hopefully, to facilitate their far-reaching development toward clinical translation.