Novel insights into paclitaxel's role on tumor-associated macrophages in enhancing PD-1 blockade in breast cancer treatment.

BACKGROUND: Triple-negative breast cancer (TNBC) poses unique challenges due to its complex nature and the need for more effective treatments. Recent studies showed encouraging outcomes from combining paclitaxel (PTX) with programmed cell death protein-1 (PD-1) blockade in treating TNBC, although the exact mechanisms behind the improved results are unclear. METHODS: We employed an integrated approach, analyzing spatial transcriptomics and single-cell RNA sequencing data from TNBC patients to understand why the combination of PTX and PD-1 blockade showed better response in TNBC patients. We focused on toll-like receptor 4 (TLR4), a receptor of PTX, and its role in modulating the cross-presentation signaling pathways in tumor-associated macrophages (TAMs) within the tumor microenvironment. Leveraging insights obtained from patient-derived data, we conducted in vitro experiments using immunosuppressive bone marrow-derived macrophages (iBMDMs) to validate if PTX could augment the cross-presentation and phagocytosis activities. Subsequently, we extended our study to an in vivo murine model of TNBC to ascertain the effects of PTX on the cross-presentation capabilities of TAMs and its downstream impact on CD8+ T cell-mediated immune responses. RESULTS: Data analysis from TNBC patients revealed that the activation of TLR4 and cross-presentation signaling pathways are crucial for the antitumor efficacy of PTX. In vitro studies showed that PTX treatment enhances the cross-presentation ability of iBMDMs. In vivo experiments demonstrated that PTX activates TLR4-dependent cross-presentation in TAMs, improving CD8+ T cell-mediated antitumor responses. The efficacy of PTX in promoting antitumor immunity was elicited when combined with PD-1 blockade, suggesting a complementary interaction. CONCLUSIONS: This study reveals how PTX boosts the effectiveness of PD-1 inhibitors in treating TNBC. We found that PTX activates TLR4 signaling in TAMs. This activation enhances their ability to present antigens, thereby boosting CD8+ T cell antitumor responses. These findings not only shed light on PTX's immunomodulatory role in TNBC but also underscore the potential of targeting TAMs' antigen presentation capabilities in immunotherapy approaches.

Novel Personalized Cancer Vaccine Using Tumor Extracellular Vesicles with Attenuated Tumorigenicity and Enhanced Immunogenicity.

Cancer vaccines offer a promising avenue in cancer immunotherapy by inducing systemic, tumor-specific immune responses. Tumor extracellular vesicles (TEVs) are nanoparticles naturally laden with tumor antigens, making them appealing for vaccine development. However, their inherent malignant properties from the original tumor cells limit their direct therapeutic use. This study introduces a novel approach to repurpose TEVs as potent personalized cancer vaccines. The study shows that inhibition of both YAP and autophagy not only diminishes the malignancy-associated traits of TEVs but also enhances their immunogenic attributes by enriching their load of tumor antigens and adjuvants. These revamped TEVs, termed attenuated yet immunogenically potentiated TEVs (AI-TEVs), showcase potential in inhibiting tumor growth, both as a preventive measure and a possible treatment for recurrent cancers. They prompt a tumor-specific and enduring immune memory. In addition, by showing that AI-TEVs can counteract cancer growth in a personalized vaccine approach, a potential strategy is presented for developing postoperative cancer immunotherapy that's enduring and tailored to individual patients.

Harnessing Oncolytic Extracellular Vesicles for Tumor Cell-Preferential Cytoplasmic Delivery of Misfolded Proteins for Cancer Immunotherapy.

In this study, extracellular vesicles (EVs) are reimagined as more than just a cellular waste disposal system and are repurposed for cancer immunotherapy. Potent oncolytic EVs (bRSVF-EVs) loaded with misfolded proteins (MPs) are engineered, which are typically considered cellular debris. By impairing lysosomal function using bafilomycin A1 and expressing the respiratory syncytial virus F protein, a viral fusogen, MPs are successfully loaded into the EVs expressing RSVF. bRSVF-EVs preferentially transplant a xenogeneic antigen onto cancer cell membranes in a nucleolin-dependent manner, triggering an innate immune response. Furthermore, bRSVF-EV-mediated direct delivery of MPs into the cancer cell cytoplasm initiates endoplasmic reticulum stress and immunogenic cell death (ICD). This mechanism of action leads to substantial antitumor immune responses in murine tumor models. Importantly, when combined with PD-1 blockade, bRSVF-EV treatment elicits robust antitumor immunity, resulting in prolonged survival and complete remission in some cases. Overall, the findings demonstrate that utilizing tumor-targeting oncolytic EVs for direct cytoplasmic delivery of MPs to induce ICD in cancer cells represents a promising approach for enhancing durable antitumor immunity.

Protein-based nanocages for vaccine development.

Protein nanocages have attracted considerable attention in various fields of nanomedicine due to their intrinsic properties, including biocompatibility, biodegradability, high structural stability, and ease of modification of their surfaces and inner cavities. In vaccine development, these protein nanocages are suited for efficient targeting to and retention in the lymph nodes and can enhance immunogenicity through various mechanisms, including excellent uptake by antigen-presenting cells and crosslinking with multiple B cell receptors. This review highlights the superiority of protein nanocages as antigen delivery carriers based on their physiological and immunological properties such as biodistribution, immunogenicity, stability, and multifunctionality. With a focus on design, we discuss the utilization and efficacy of protein nanocages such as virus-like particles, caged proteins, and artificial caged proteins against cancer and infectious diseases such as coronavirus disease 2019 (COVID-19). In addition, we summarize available knowledge on the protein nanocages that are currently used in clinical trials and provide a general outlook on conventional distribution techniques and hurdles faced, particularly for therapeutic cancer vaccines.

Forecasting the Reduction in Urban Air Pollution by Expansion of Market Shares of Eco-Friendly Vehicles: A Focus on Seoul, Korea.

Due to global climate change, various countries have agreed upon the use of conventions. In this study, the eco-friendly vehicular policy on carbon neutrality implemented in Seoul, Korea, was examined. To this end, various policy-based scenarios were set, and the changes in automotive exhaust gas emissions were evaluated and compared. The evaluation method combined macroscopic and microscopic emission models as its analysis framework. Micro-traffic data available in Korea were used for analyses, and the results for all autonomous districts were derived to cover the entire area of Seoul. The findings confirmed that the most effective measure is the initial replacement of old, mid-size, or large diesel passenger cars with eco-friendly vehicles (Middle-sized: Scenario 2-1 5.52%, Scenario 2-2 6.86%, Scenario 3-1 80.93%, and Scenario 3-2 83.98%). The replacement of old vehicles exhibited the highest effect in all tested scenarios, while the initial replacement of diesel vehicles was more effective than the replacement of gasoline and liquified petroleum gas vehicles (Diesel: Scenario2-1 6.64%, Scenario 2-2 8.21%, Scenario3-1 86.23%, and Scenario 3-2 90.51%). Among the autonomous districts of Seoul, the Gangnam-gu area exhibited the largest emission-reduced effect among all the tested scenarios (Gangnam-gu: Scenario 2-1 5.80%, Scenario 2-2 6.74%, Scenario 3-1 80.44%, and Scenario 3-2 82.62%). Overall, it was demonstrated that the findings of this study may have significant policy implications in terms of urban emission changes pertaining to transportation.

Advantage of extracellular vesicles in hindering the CD47 signal for cancer immunotherapy.

The cluster of differentiation 47 (CD47) protein is abundantly expressed on various malignant cells and suppresses the phagocytic function of macrophages and dendritic cells. High CD47 expression levels are correlated with poor cancer survival. Antagonizing CD47 antibodies with potent antitumor effects have been developed in clinical trials, but have critical side effects, inducing anemia and thrombocytopenia. To develop a safe and potent CD47 blockade, we designed extracellular vesicles (EVs) harboring signal regulatory protein alpha (SIPRα)-EV-SIRPα (EVs that express SIPRα). EV-SIRPα showed minimal toxic effects on hematologic parameters and utilized RBCs as delivery vehicles to tumors rather than inducing anemia. EV-SIRPα inhibited ligation of residual CD47 molecules, which attribute to the EV-endocytosis-mediated CD47 depletion and steric hindrance of EV. In an immunologically cold tumor model, EV-SIRPα induced tumor-specific T-cell-mediated antitumor effects. When directly administered to the accessible lesions, EV-SIRPα monotherapy elicited an abscopal effect in the B16F10 tumor model by increasing immune cell infiltration and CD8+-mediated immunity against non-treated tumors. The combinational approach by loading doxorubicin into the EV-SIRPα dramatically reduced the tumor burden and led to 80% complete remission rate. Thus, a potent EV-based CD47 blockade that is hematologically safe, has efficient signaling blocking efficacy, and has systemic antitumor immunity against cancer is recommended.

A Multivalent Vaccine Based on Ferritin Nanocage Elicits Potent Protective Immune Responses against SARS-CoV-2 Mutations.

The SARS-CoV-2 pandemic has created a global public crisis and heavily affected personal lives, healthcare systems, and global economies. Virus variants are continuously emerging, and, thus, the pandemic has been ongoing for over two years. Vaccines were rapidly developed based on the original SARS-CoV-2 (Wuhan-Hu-1) to build immunity against the coronavirus disease. However, they had a very low effect on the virus' variants due to their low cross-reactivity. In this study, a multivalent SARS-CoV-2 vaccine was developed using ferritin nanocages, which display the spike protein from the Wuhan-Hu-1, B.1.351, or B.1.429 SARS-CoV-2 on their surfaces. We show that the mixture of three SARS-CoV-2 spike-protein-displaying nanocages elicits CD4+ and CD8+ T cells and B-cell immunity successfully in vivo. Furthermore, they generate a more consistent antibody response against the B.1.351 and B.1.429 variants than a monovalent vaccine. This leads us to believe that the proposed ferritin-nanocage-based multivalent vaccine platform will provide strong protection against emerging SARS-CoV-2 variants of concern (VOCs).

Rho-Kinase as a Target for Cancer Therapy and Its Immunotherapeutic Potential.

Cancer immunotherapy is fast rising as a prominent new pillar of cancer treatment, harnessing the immune system to fight against numerous types of cancer. Rho-kinase (ROCK) pathway is involved in diverse cellular activities, and is therefore the target of interest in various diseases at the cellular level including cancer. Indeed, ROCK is well-known for its involvement in the tumor cell and tumor microenvironment, especially in its ability to enhance tumor cell progression, migration, metastasis, and extracellular matrix remodeling. Importantly, ROCK is also considered to be a novel and effective modulator of immune cells, although further studies are needed. In this review article, we describe the various activities of ROCK and its potential to be utilized in cancer treatment, particularly in cancer immunotherapy, by shining a light on its activities in the immune system.

Statin in combination with cisplatin makes favorable tumor-immune microenvironment for immunotherapy of head and neck squamous cell carcinoma.

The purpose of this study was to determine whether statins can enhance anticancer effects in head and neck squamous cell carcinoma (HNSCC) when used with cisplatin and act as immunogenic cell death (ICD) inducers that can be used in cancer immunotherapy. Statins alone showed both in vitro and in vivo inhibitory effects against HNSCC, and synergistic antitumor effects were observed when combined with cisplatin in a syngeneic murine HNSCC model. Statins increased calreticulin exposure and endoplasmic reticulum stress-related signals in HNSCC cells. In addition, it was confirmed that statins could activate antigen-presenting cells and tumor-specific CD8+ T cells with an increase in their numbers in the tumor tissues and draining lymph nodes, with this effect showing significant improvement following the combination therapy with cisplatin. Moreover, in triple combination with both cisplatin and anti-programmed cell death 1 receptor (anti-PD-1) antibody, statins dramatically induced further tumor eradication and improved the survival of tumor-bearing mice. Taken together, these results demonstrate that statins, administered in combination with anti-PD-1 antibody, could enhance the anticancer effect of cisplatin and potentiate the efficacy of immunotherapy for HNSCC and present a rationale for repurposing statins as an adjuvant immunotherapeutic option for HNSCC.

Nanocages displaying SIRP gamma clusters combined with prophagocytic stimulus of phagocytes potentiate anti-tumor immunity.

Antigen-presenting cells (APCs), including macrophages and dendritic cells (DCs), play a crucial role in bridging innate and adaptive immunity; thereby, innate immune checkpoint blockade-based therapy is an attractive approach for the induction of sustainable tumor-specific immunity. The interaction between the cluster of differentiation 47 (CD47) on tumor and signal-regulatory protein alpha (SIRPα) on phagocytic cells inhibits the phagocytic function of APCs, acting as a "don't eat me" signal. Accordingly, CD47 blockade is known to increase tumor cell phagocytosis, eliciting tumor-specific CD8+ T-cell immunity. Here, we introduced a nature-derived nanocage to deliver SIRPγ for blocking of antiphagocytic signaling through binding to CD47 and combined it with prophagocytic stimuli using a metabolic reprogramming reagent for APCs (CpG-oligodeoxynucleotides). Upon delivering the clustered SIRPγ variant, the nanocage showed enhanced CD47 binding profiles on tumor cells, thereby promoting active engulfment by phagocytes. Moreover, combination with CpG potentiated the prophagocytic ability, leading to the establishment of antitumorigenic surroundings. This combination treatment could competently inhibit tumor growth by invigorating APCs and CD8+ T-cells in TMEs in B16F10 orthotopic tumor models, known to be resistant to CD47-targeting therapeutics. Collectively, enhanced delivery of an innate immune checkpoint antagonist with metabolic modulation stimuli of immune cells could be a promising strategy for arousing immune responses against cancer.

Statin-mediated inhibition of RAS prenylation activates ER stress to enhance the immunogenicity of KRAS mutant cancer.

BACKGROUND: Statins preferentially promote tumor-specific apoptosis by depleting isoprenoid such as farnesyl pyrophosphate and geranylgeranyl pyrophosphate. However, statins have not yet been approved for clinical cancer treatment due, in part, to poor understanding of molecular determinants on statin sensitivity. Here, we investigated the potential of statins to elicit enhanced immunogenicity of KRAS-mutant (KRASmut) tumors. METHODS: The immunogenicity of treated cancer cells was determined by western blot, flow cytometry and confocal microscopy. The immunotherapeutic efficacy of mono or combination therapy using statin was assessed in KRASmut tumor models, including syngeneic colorectal cancer and genetically engineered lung and pancreatic tumors. Using NanoString analysis, we analyzed how statin influenced the gene signatures associated with the antigen presentation of dendritic cells in vivo and evaluated whether statin could induce CD8+ T-cell immunity. Multiplex immunohistochemistry was performed to better understand the complicated tumor-immune microenvironment. RESULTS: Statin-mediated inhibition of KRAS prenylation provoked severe endoplasmic reticulum (ER) stress by attenuating the anti-ER stress effect of KRAS mutation, thereby resulting in the immunogenic cell death (ICD) of KRASmut cancer cells. Moreover, statin-mediated ICD enhanced the cross-priming ability of dendritic cells, thereby provoking CD8+ T-cell immune responses against KRASmut tumors. Combination therapy using statin and oxaliplatin, an ICD inducer, significantly enhanced the immunogenicity of KRASmut tumors and promoted tumor-specific immunity in syngeneic and genetically engineered KRASmut tumor models. Along with immune-checkpoint inhibitors, the abovementioned combination therapy overcame resistance to PD-1 blockade therapies, improving the survival rate of KRASmut tumor models. CONCLUSIONS: Our findings suggest that KRAS mutation could be a molecular target for statins to elicit potent tumor-specific immunity.

In situ immunogenic clearance induced by a combination of photodynamic therapy and rho-kinase inhibition sensitizes immune checkpoint blockade response to elicit systemic antitumor immunity against intraocular melanoma and its metastasis.

BACKGROUND: Uveal melanoma (UM) is the most frequent intraocular malignancy and is resistant to immunotherapy. Nearly 50% of patients with UM develop metastatic disease, and the overall survival outcome remains very poor. Therefore, a treatment regimen that simultaneously targets primary UM and prevents metastasis is needed. Here, we suggest an immunotherapeutic strategy for UM involving a combination of local photodynamic therapy (PDT), rho-kinase (ROCK) inhibitor, and PD-1/PD-L1 immune checkpoint blockade. METHODS: The antitumor efficacy and immune response of monotreatment or combinational treatment were evaluated in B16F10-bearing syngeneic mouse models. Abscopal antitumor immune responses induced by triple-combinational treatment were validated in syngeneic bilateral B16F10 models. After each treatment, the immune profiles and functional examinations were assessed in tumors and tumor draining lymph nodes by flow cytometry, ELISA, and immunofluorescence assays. In orthotopic intraocular melanoma models, the location of the immune infiltrate in the tumor microenvironment (TME) was evaluated after each treatment by multiplex immunohistochemistry and metastatic nodules were monitored. RESULTS: PDT with Ce6-embedded nanophotosensitizer (FIC-PDT) elicited immunogenic cell death and stimulated antigen-presenting cells. In situ immunogenic clearance induced by a combination of FIC-PDT with ripasudil, a clinically approved ROCK inhibitor, stimulated antigen-presenting cells, which in turn primed tumor-specific cytotoxic T cells. Moreover, local immunogenic clearance sensitized PD-1/PD-L1 immune checkpoint blockade responses to reconstruct the TME immune phenotypes of cold tumors into hot tumors, resulting in recruitment of robust cytotoxic CD8+ T cells in the TME, propagation of systemic antitumor immunity to mediate abscopal effects, and prolonged survival. In an immune-privileged orthotopic intraocular melanoma model, even low-dose FIC-PDT and ripasudil combined with anti-PD-L1 antibody reduced the primary tumor burden and prevented metastasis. CONCLUSIONS: A combination of localized FIC-PDT and a ROCK inhibitor exerted a cancer vaccine-like function. Immunogenic clearance led to the trafficking of CD8+ T cells into the primary tumor site and sensitized the immune checkpoint blockade response to evoke systemic antitumor immunity to inhibit metastasis, one of the major challenges in UM therapy. Thus, immunogenic clearance induced by FIC-PDT and ROCK inhibitor combined with anti-PD-L1 antibody could be a potent immunotherapeutic strategy for UM.

Emerging Prospects of Exosomes for Cancer Treatment: From Conventional Therapy to Immunotherapy.

Exosomes are a class of extracellular vesicles of around 100 nm in diameter that are secreted by most cells and contain various bioactive molecules reflecting their cellular origin and mediate intercellular communication. Studies of these exosomal features in tumor pathogenesis have led to the development of therapeutic and diagnostic approaches using exosomes for cancer therapy. Exosomes have many advantages for conveying therapeutic agents such as small interfering RNAs, microRNAs, membrane-associated proteins, and chemotherapeutic compounds; thus, they are considered a prime candidate as a delivery tool for cancer treatment. Since exosomes also provide an optimal microenvironment for the effective function of immunomodulatory factors, exosomes harboring bioactive molecules have been bioengineered as cancer immunotherapies that can effectively activate each stage of the cancer immunity cycle to successfully elicit cancer-specific immunity. This review discusses the advantages of exosomes for treating cancer and the challenges that must be overcome for their successful clinical development.

Degradation of tumour stromal hyaluronan by small extracellular vesicle-PH20 stimulates CD103+ dendritic cells and in combination with PD-L1 blockade boosts anti-tumour immunity.

Highly accumulated hyaluronan (HA) not only provides a physiological barrier but also supports an immune-suppressive tumour microenvironment. High-molecular-weight (HMW)-HA inhibits the activation of immune cells and their access into tumour tissues, whereas, low-molecular-weight oligo-HA is known to potentially activate dendritic cells (DCs). In this paper, we investigated whether small extracellular vesicle (EVs)-PH20 hyaluronidase induces tumour HA degradation, which, in turn, activates DCs to promote anti-cancer immune responses. Informed by our previous work, we used a small EV carrying GPI-anchored PH20 hyaluronidase (Exo-PH20) that could deeply penetrate into tumour foci via HA degradation. We found that Exo-PH20-treatment successfully activates the maturation and migration of DCs in vivo, particularly CD103+ DCs leading to the activation of tumour-specific CD8+ T cells, which work together to inhibit tumour growth. Moreover, combination with anti-PD-L1 antibody provided potent tumour-specific CD8+ T cell immune responses as well as elicited prominent tumour growth inhibition both in syngenic and spontaneous breast cancer models, and this anti-tumour immunity was durable. Together, these results present new insights for HA degradation by Exo-PH20, providing a better understanding of oligo HA-triggered immune responses to cancer.

Bullying and discrimination experiences among Korean-American adolescents.

The bullying experiences of Korean-American adolescents (N = 295) were explored in relation to discrimination and mental health outcomes. Bullying experiences were assessed by the Bully Survey (Swearer, 2005), discrimination by the Perceived Ethnic and Racial Discrimination Scale (Way, 1997) and depression by the Center for Epidemiological Studies - Depression Scale (CES-D). Those who reported being bullied (31.5%) as well as those who reported both being bullied and bullying others (15.9%) experienced a higher level of depression, which was elevated beyond the clinically significant level of CES-D. The results of a LISREL model suggest that the experiences of bullying among Korean/Asian-American adolescents and their related mental health issues need to be addressed in a comprehensive context of their discrimination experiences, acculturation, family and school environments.