Interference of ATP-Adenosine Axis by Engineered Biohybrid for Amplifying Immunogenic Cell Death-Mediated Antitumor Immunotherapy.

Immunogenic cell death (ICD) often results in the production and accumulation of adenosine (ADO), a byproduct that negatively impacts the therapeutic effect as well as facilitates tumor development and metastasis. Here, an innovative strategy is elaborately developed to effectively activate ICD while avoiding the generation of immunosuppressive adenosine. Specifically, ZIF-90, an ATP-responsive consumer, is synthesized as the core carrier to encapsulate AB680 (CD73 inhibitor) and then coated with an iron-polyphenol layer to prepare the ICD inducer (AZTF), which is further grafted onto prebiotic bacteria via the esterification reaction to obtain the engineered biohybrid (Bc@AZTF). Particularly, the designed Bc@AZTF can actively enrich in tumor sites and respond to the acidic tumor microenvironment to offload AZTF nanoparticles, which can consume intracellular ATP (iATP) content and simultaneously inhibit the ATP-adenosine axis to reduce the accumulation of adenosine, thereby alleviating adenosine-mediated immunosuppression and strikingly amplifying ICD effect. Importantly, the synergy of anti-PD-1 (αPD-1) with Bc@AZTF not only establishes a collaborative antitumor immune network to potentiate effective tumoricidal immunity but also activates long-lasting immune memory effects to manage tumor recurrence and rechallenge, presenting a new paradigm for ICD treatment combined with adenosine metabolism.

CX3CL1 release during immunogenic apoptosis is associated with enhanced anti-tumour immunity.

Introduction: Immunogenic cell death (ICD) has emerged as a novel option for cancer immunotherapy. The key determinants of ICD encompass antigenicity (the presence of antigens) and adjuvanticity, which involves the release of damage-associated molecular patterns (DAMPs) and various cytokines and chemokines. CX3CL1, also known as neurotactin or fractalkine, is a chemokine involved in cellular signalling and immune cell interactions. CX3CL1 has been denoted as a "find me" signal that stimulates chemotaxis of immune cells towards dying cells, facilitating efferocytosis and antigen presentation. However, in the context of ICD, it is uncertain whether CX3CL1 is an important mediator of the effects of ICD. Methods: In this study, we investigated the intricate role of CX3CL1 in immunogenic apoptosis induced by mitoxantrone (MTX) in cancer cells. The Luminex xMAP technology was used to quantify murine cytokines, chemokines and growth factors to identify pivotal regulatory cytokines released by murine fibrosarcoma MCA205 and melanoma B16-F10 cells undergoing ICD. Moreover, a murine tumour prophylactic vaccination model was employed to analyse the effect of CX3CL1 on the activation of an adaptive immune response against MCA205 cells undergoing ICD. Furthermore, thorough analysis of the TCGA-SKCM public dataset from 98 melanoma patients revealed the role of CX3CL1 and its receptor CX3CR1 in melanoma patients. Results: Our findings demonstrate enhanced CX3CL1 release from apoptotic MCA205 and B16-F10 cells (regardless of the cell type) but not if they are undergoing ferroptosis or accidental necrosis. Moreover, the addition of recombinant CX3CL1 to non-immunogenic doses of MTX-treated, apoptotically dying cancer cells in the murine prophylactic tumour vaccination model induced a robust immunogenic response, effectively increasing the survival of the mice. Furthermore, analysis of melanoma patient data revealed enhanced survival rates in individuals exhibiting elevated levels of CD8+ T cells expressing CX3CR1. Conclusion: These data collectively underscore the importance of the release of CX3CL1 in eliciting an immunogenic response against dying cancer cells and suggest that CX3CL1 may serve as a key switch in conferring immunogenicity to apoptosis.

GSDME-mediated pyroptosis promotes anti-tumor immunity of neoadjuvant chemotherapy in breast cancer.

Paclitaxel and anthracycline-based chemotherapy is one of the standard treatment options for breast cancer. However, only about 6-30% of breast cancer patients achieved a pathological complete response (pCR), and the mechanism responsible for the difference is still unclear. In this study, random forest algorithm was used to screen feature genes, and artificial neural network (ANN) algorithm was used to construct an ANN model for predicting the efficacy of neoadjuvant chemotherapy for breast cancer. Furthermore, digital pathology, cytology, and molecular biology experiments were used to verify the relationship between the efficacy of neoadjuvant chemotherapy and immune ecology. It was found that paclitaxel and doxorubicin, an anthracycline, could induce typical pyroptosis and bubbling in breast cancer cells, accompanied by gasdermin E (GSDME) cleavage. Paclitaxel with LDH release and Annexin V/PI doubule positive cell populations, and accompanied by the increased release of damage-associated molecular patterns, HMGB1 and ATP. Cell coculture experiments also demonstrated enhanced phagocytosis of macrophages and increased the levels of IFN-γ and IL-2 secretion after paclitaxel treatment. Mechanistically, GSDME may mediate paclitaxel and doxorubicin-induced pyroptosis in breast cancer cells through the caspase-9/caspase-3 pathway, activate anti-tumor immunity, and promote the efficacy of paclitaxel and anthracycline-based neoadjuvant chemotherapy. This study has practical guiding significance for the precision treatment of breast cancer, and can also provide ideas for understanding molecular mechanisms related to the chemotherapy sensitivity.

Photodynamic Therapy Synergizes CD47 Blockade Strategy for Enhanced Antitumor Therapy.

The antitumor strategies based on innate immunity activation have become favored by researchers in recent years. In particular, strategies targeting antiphagocytic signaling blockade to enhance phagocytosis have been widely reported. For example, the addition of prophagocytic signals such as calreticulin could make the strategy significantly more effective. In this study, an antitumor strategy that combines photodynamic therapy (PDT) with CD47 blockade has been reported. This approach promotes the maturation of dendritic cells and the presentation of tumor antigens by PDT-mediated tumor immunogenic cell death, as well as the enhancement of cytotoxic T lymphocyte infiltration in tumor areas and the phagocytic activity of phagocytes. Furthermore, the downregulation and blockage of CD47 protein could further promote phagocytic activity, strengthen the innate immune system, and ultimately elevate the antitumor efficacy and inhibit tumor metastasis.

Advanced Strategies for Strengthening the Immune Activation Effect of Traditional Antitumor Therapies.

The utilization of traditional therapies (TTS), such as chemotherapy, reactive oxygen species-based therapy, and thermotherapy, to induce immunogenic cell death (ICD) in tumor cells has emerged as a promising strategy for the activation of the antitumor immune response. However, the limited effectiveness of most TTS in inducing the ICD effect of tumors hinders their applications in combination with immunotherapy. To address this challenge, various intelligent strategies have been proposed to strengthen the immune activation effect of these TTS, and then achieve synergistic antitumor efficacy with immunotherapy. These strategies primarily focus on augmenting the tumor ICD effect or facilitating the antigen (released by the ICD tumor cells) presentation process during TTS, and they are systematically summarized in this review. Finally, the existing bottlenecks and prospects of TTS in the application of tumor immune regulation are also discussed.

CD44/PD-L1-mediated networks in drug resistance and immune evasion of breast cancer stem cells: Promising targets of natural compounds.

Cancer stem cells (CSCs) significantly interfere with immunotherapy, leading to challenges such as low response rates and acquired resistance. PD-L1 expression is associated with the CSC population's overexpression of CD44. Mounting evidence suggests that the breast cancer stem cell (BCSC) marker CD44 and the immune checkpoint PD-L1 contribute to treatment failure through their networks. Natural compounds can overcome therapy resistance in breast cancer by targeting mechanisms underlying resistance in BCSCs. This review provides an updated insight into the CD44 and PD-L1 networks of BCSCs in mediating metastasis and immune evasion. The review critically examines existing literature, providing a comprehensive understanding of the topic and emphasizing the impact of natural flavones on the signaling pathways of BCSCs. Additionally, the review discusses the potential of natural compounds in targeting CD44 and PD-L1 in breast cancer (BC). Natural compounds consistently show potential in targeting regulatory mechanisms of BCSCs, inducing loss of stemness, and promoting differentiation. They offer a promising approach for developing alternative therapeutic strategies to manage breast cancer.

Light-Activated In Situ Vaccine with Enhanced Cytotoxic T Lymphocyte Infiltration and Function for Potent Cancer Immunotherapy.

In situ cancer vaccination is an attractive strategy that stimulates protective antitumor immunity. Cytotoxic T lymphocytes (CTLs) are major mediators of the adaptive immune defenses, with critical roles in antitumor immune response and establishing immune memory, and are consequently extremely important for in situ vaccines to generate systemic and lasting antitumor efficacy. However, the dense extracellular matrix and hypoxia in solid tumors severely impede the infiltration and function of CTLs, ultimately compromising the efficacy of in situ cancer vaccines. To address this issue, a robust in situ cancer vaccine, Au@MnO2 nanoparticles (AMOPs), based on a gold nanoparticle core coated with a manganese dioxide shell is developed. The AMOPs modulated the unfavorable tumor microenvironment (TME) to restore CTLs infiltration and function and efficiently induced immunogenic cell death. The Mn2+-mediated stimulator of the interferon genes pathway can be activated to further augment the therapeutic efficacy of the AMOPs. Thus, the AMOPs vaccine successfully elicited long-lasting antitumor immunity to considerably inhibit primary, recurrent, and metastatic tumors. This study not only highlights the importance of revitalizing CTLs efficacy against solid tumors but also makes progress toward overcoming TME barriers for sustained antitumor immunity.

Reactive oxygen species of tumor microenvironment: Harnessing for immunogenic cell death.

The tumor microenvironment (TME) is a dynamic and complex system that undergoes continuous changes in its network architecture, notably affecting redox homeostasis. These alterations collectively shape a diverse ecosystem actively supporting tumor progression by influencing the cellular and molecular components of the TME. Despite the remarkable clinical advancements in cancer immunotherapy, its spectrum of clinical utility is limited by the altered TME and inadequate tumor immunogenicity. Recent studies have revealed that some conventional and targeted therapy strategies can augment the efficacy of immunotherapy even in patients with less immunogenic solid tumors. These strategies provoke immunogenic cell death (ICD) through the ROS-dependent liberation of damage-associated molecular patterns (DAMPs). These DAMPs recognize and bind with Pattern Recognition Receptors (PRRs) on immune cells, activating and maturing defense cells, ultimately leading to a robust antitumor immune response. The present review underscores the pivotal role of redox homeostasis in orchestrating the transition of TME from a cold to a hot phenotype and the ROS-ICD axis in immune response induction. Additionally, it provides up-to-date insights into strategies that leverage ROS generation to induce ICD. The comprehensive analysis aims to develop ROS-based effective cancer immunotherapies for less immunogenic tumors.

A pH-triggered N-oxide polyzwitterionic nano-drug loaded system for the anti-tumor immunity activation research.

Triple negative breast cancer (TNBC) has the characteristics of low immune cell infiltration, high expression of tumor programmed death ligand 1 (PD-L1), and abundant cancer stem cells. Systemic toxicity of traditional chemotherapy drugs due to poor drug selectivity, and chemotherapy failure due to tumor drug resistance and other problems, so it is particularly important to find new cancer treatment strategies for TNBC with limited treatment options. Both the anti-tumor natural drugs curcumin and ginsenoside Rg3 can exert anti-tumor effects by inducing immunogenic cell death (ICD) of tumor cells, reducing PD-L1 expression, and reducing cancer stem cells. However, they have the disadvantages of poor water solubility, low bioavailability, and weak anti-tumor effect of single agents. We used vinyl ether bonds to link curcumin (Cur) with N-O type zwitterionic polymers and at the same time encapsulated ginsenoside Rg3 to obtain hyperbranched zwitterionic drug-loaded micelles OPDEA-PGED-5HA@Cur@Rg3 (PPH@CR) with pH response. In vitro cell experiments and in vivo animal experiments have proved that PPH@CR could not only promote the maturation of dendritic cells (DCs) and increase the CD4+ T cells and CD8+ T cells by inducing ICD in tumor cells but also reduce the expression of PD-L1 in tumor tissues, and reduce cancer stem cells and showed better anti-tumor effects and good biological safety compared with free double drugs, which is a promising cancer treatment strategy.

Plant-derived natural compounds: A new frontier in inducing immunogenic cell death for cancer treatment.

Immunogenic cell death (ICD) can activate adaptive immune response in the host with normal immune system. Some synthetic chemotherapeutic drugs and natural compounds have shown promising results in cancer treatment by triggering the release of damage-associated molecules (DAMPs) to trigger ICD. However, most chemotherapeutic drugs exhibit non-selective cytotoxicity and may also induce and promote metastasis, thereby significantly reducing their clinical efficacy. Among the natural compounds that can induce ICD, plant-derived compounds account for the largest proportion, which are of increasing value in the treatment of cancer. Understanding which plant-derived natural compounds can induce ICD and how they induce ICD is crucial for developing strategies to improve chemotherapy outcomes. In this review, we focus on the recent findings regarding plant-derived natural compounds that induce ICD according to the classification of flavonoids, alkaloids, glycosides, terpenoids and discuss the potential mechanisms including endoplasmic reticulum (ER) stress, DNA damage, apoptosis, necroptosis autophagy, ferroptosis. In addition, plant-derived natural compounds that can enhance the ICD induction ability of conventional therapies for cancer treatment is also elaborated. The rational use of plant-derived natural compounds to induce ICD is helpful for the development of new cancer treatment methods.

Metformin induces tumor immunogenic cell death in ovarian cancer by activating AMPK pathway.

Inducing immunogenic cell death (ICD) process may be an important antitumor strategy in ovarian cancer (OC). Metformin (Met) has been shown to have antitumor effects in OC, but whether it mediates the ICD to inhibit OC process is unclear. Human OC cell lines (SKOV3 and A2780) were treated with Met. Dendritic cell (DC) and CD8+T cells were isolated from the peripheral blood mononuclear cells of volunteers. Cell counting kit 8 assay was used to measure cell viability, and immunofluorescence staining was performed to detect the percentages of membrane and intracellular calreticulin (CRT). CRT level, DC maturation and effector cell activation were evaluated by flow cytometry. The levels of IL-10 and IFN-γ, as well as the releasements of HMGB1 and ATP, were detected using corresponding kits. The protein levels of heat shock protein 70/90 (HSP70/90) and AMPKα were tested by western blot analysis, and the mRNA levels of CD80, CD86, IL-10, and IFN-γ were measured by quantitative real-time PCR. Colony formation assay was utilized for assessing cell cytotoxicity. Mice transplanted tumor model was constructed to assess the effect of Met on OC tumor growth, and immunohistochemistry staining was used to analyze CD80+ and CD86+ cells in mice tumor tissues. Our data showed that Met inhibited OC cell viability and induced CRT exposure. Besides, Met could promote the release of HMGB1 and ATP, as well as induce DC maturation. In vivo experiments suggested that Met restrained OC tumor growth via activating antitumor immune response. Moreover, Met activated AMPK pathway, and silenced AMPK pathway reversed the promoting effect of Met on CRT exposure and the releasements of HMGB1 and ATP in OC cells. In conclusion, Met induced ICD-mediated immune destruction in OC via activating AMPK pathway, indicating that Met might be used in the immunotherapy of OC.

Hainanenin-1, an oncolytic peptide, triggers immunogenic cell death via STING activation in triple-negative breast cancer.

BACKGROUND: In triple-negative breast cancer (TNBC) therapy, insufficient tumor infiltration by lymphocytes significantly hinders the efficacy of immune checkpoint inhibitors. We have previously demonstrated that Hainanenin-1 (HN-1), a host defense peptide (HDP) identified from Hainan frog skin, induces breast cancer apoptosis and boots anti-tumor immunity via unknown mechanism. METHODS: We used in vitro experiments to observe immunogenic cell death (ICD) indicators in HN-1-treated TNBC cell lines, a mouse tumor model to verify HN-1 promotion of mice anti-tumor immune response, and an in vitro drug sensitivity test of patient-derived breast cancer cells to verify the inhibitory effect of HN-1. RESULTS: HN-1 induced ICD in TNBC in a process during which damage-associated molecular patterns (DAMPs) were released that could further increase the anti-tumor immune response. The secretion level of interleukin 2 (IL-2), IL-12, and interferon γ in the co-culture supernatant was increased, and dendritic cells (DCs) were activated via a co-culture with HN-1-pretreated TNBC cells. As a result, HN-1 increased the infiltration of anti-tumor immune cells (DCs and T lymphocytes) in the mouse model bearing both 4T1 and EMT6 tumors. Meanwhile, regulatory T cells and myeloid-derived suppressor cells were suppressed. In addition, HN-1 induced DNA damage, and double-strand DNA release in the cytosol was significantly enhanced, indicating that HN-1 might stimulate ICD via activation of STING pathway. The knockdown of STING inhibited HN-1-induced ICD. Of note, HN-1 exhibited inhibitory effects on patient-derived breast cancer cells under three-dimensional culture conditions. CONCLUSIONS: Collectively, our study demonstrated that HN-1 could be utilized as a potential compound that might augment immunotherapy effects in patients with TNBC.

Tumor phagocytosis-driven STING activation invigorates antitumor immunity and reprograms the tumor micro-environment.

Immunogenic cell death (ICD) holds the potential for in situ tumor vaccination while concurrently eradicating tumors and stimulating adaptive immunity. Most ICD inducers, however, elicit insufficient immune responses due to negative feedback against ICD biomarkers, limited infiltration of antitumoral immune cells, and the immunosuppressive tumor micro-environment (TME). Recent findings highlight the pivotal roles of stimulators of interferon gene (STING) activation, particularly in stimulating antigen-presenting cells (APCs) and TME reprogramming, addressing ICD limitations. Herein, we introduced 'tumor phagocytosis-driven STING activation', which involves the activation of STING in APCs during the recognition of ICD-induced cancer cells. We developed a polypeptide-based nanocarrier encapsulating both doxorubicin (DOX) and diABZI STING agonist 3 (dSA3) to facilitate this hypothesis in vitro and in vivo. After systemic administration, nanoparticles predominantly accumulated in tumor tissue and significantly enhanced anticancer efficacy by activating tumor phagocytosis-driven STING activation in MC38 and TC1 tumor models. Immunological activation of APCs occurred within 12 h, subsequently leading to the activation of T cells within 7 days, observed in both the TME and spleen. Furthermore, surface modification of nanoparticles with cyclic RGD (cRGD) moieties, which actively target integrin αvß3, enhances tumor accumulation and eradication, thereby verifying the establishment of systemic immune memory. Collectively, this study proposes the concept of tumor phagocytosis-driven STING activation and its effectiveness in generating short-term and long-term immune responses.

Ultrasound-responsive Bi2MoO6-MXene heterojunction as ferroptosis inducers for stimulating immunogenic cell death against ovarian cancer.

BACKGROUND: Ovarian cancer (OC) has the highest fatality rate among all gynecological malignancies, necessitating the exploration of novel, efficient, and low-toxicity therapeutic strategies. Ferroptosis is a type of programmed cell death induced by iron-dependent lipid peroxidation and can potentially activate antitumor immunity. Developing highly effective ferroptosis inducers may improve OC prognosis. RESULTS: In this study, we developed an ultrasonically controllable two-dimensional (2D) piezoelectric nanoagonist (Bi2MoO6-MXene) to induce ferroptosis. A Schottky heterojunction between Bi2MoO6 (BMO) and MXene reduced the bandgap width by 0.44 eV, increased the carrier-separation efficiency, and decreased the recombination rate of electron-hole pairs under ultrasound stimulation. Therefore, the reactive oxygen species yield was enhanced. Under spatiotemporal ultrasound excitation, BMO-MXene effectively inhibited OC proliferation by more than 90%, induced lipid peroxidation, decreased mitochondrial-membrane potential, and inactivated the glutathione peroxidase and cystathionine transporter protein system, thereby causing ferroptosis in tumor cells. Ferroptosis in OC cells further activated immunogenic cell death, facilitating dendritic cell maturation and stimulating antitumor immunity. CONCLUSION: We have succeeded in developing a highly potent ferroptosis inducer (BMO-MXene), capable of inhibiting OC progression through the sonodynamic-ferroptosis-immunogenic cell death pathway.

Modified mesenchymal stromal cells by in vitro transcribed mRNA: a therapeutic strategy for hepatocellular carcinoma.

BACKGROUND: Mesenchymal stromal cells (MSCs) tropism for tumours allows their use as carriers of antitumoural factors and in vitro transcribed mRNA (IVT mRNA) is a promising tool for effective transient expression without insertional mutagenesis risk. Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a cytokine with antitumor properties by stimulating the specific immune response. The aim of this work was to generate modified MSCs by IVT mRNA transfection to overexpress GM-CSF and determine their therapeutic effect alone or in combination with doxorubicin (Dox) in a murine model of hepatocellular carcinoma (HCC). METHODS: DsRed or GM-CSF IVT mRNAs were generated from a cDNA template designed with specific primers followed by reverse transcription. Lipofectamine was used to transfect MSCs with DsRed (MSC/DsRed) or GM-CSF IVT mRNA (MSC/GM-CSF). Gene expression and cell surface markers were determined by flow cytometry. GM-CSF secretion was determined by ELISA. For in vitro experiments, the J774 macrophage line and bone marrow monocytes from mice were used to test GM-CSF function. An HCC model was developed by subcutaneous inoculation (s.c.) of Hepa129 cells into C3H/HeN mice. After s.c. injection of MSC/GM-CSF, Dox, or their combination, tumour size and mouse survival were evaluated. Tumour samples were collected for mRNA analysis and flow cytometry. RESULTS: DsRed expression by MSCs was observed from 2 h to 15 days after IVT mRNA transfection. Tumour growth remained unaltered after the administration of DsRed-expressing MSCs in a murine model of HCC and MSCs expressing GM-CSF maintained their phenotypic characteristic and migration capability. GM-CSF secreted by modified MSCs induced the differentiation of murine monocytes to dendritic cells and promoted a proinflammatory phenotype in the J774 macrophage cell line. In vivo, MSC/GM-CSF in combination with Dox strongly reduced HCC tumour growth in C3H/HeN mice and extended mouse survival in comparison with individual treatments. In addition, the tumours in the MSC/GM-CSF + Dox treated group exhibited elevated expression of proinflammatory genes and increased infiltration of CD8 + T cells and macrophages. CONCLUSIONS: Our results showed that IVT mRNA transfection is a suitable strategy for obtaining modified MSCs for therapeutic purposes. MSC/GM-CSF in combination with low doses of Dox led to a synergistic effect by increasing the proinflammatory tumour microenvironment, enhancing the antitumoural response in HCC.

Targeted delivery of anti-miRNA21 sensitizes PD-L1high tumor to immunotherapy by promoting immunogenic cell death.

Rationale: Growing evidence has demonstrated that miRNA-21 (miR-21) upregulation is closely associated with tumor pathogenesis. However, the mechanisms by which miR-21 inhibition modulates the immunosuppressive tumor microenvironment (TME) and improves tumor sensitivity to immune checkpoint blockade therapies remain largely unexplored. In this study, we demonstrate the precise delivery of anti-miR-21 using a PD-L1-targeting peptide conjugate (P21) to the PD-L1high TME. Methods: Investigating miR-21 inhibition mechanisms involved conducting quantitative real-time PCR, western blot, flow cytometry, and confocal microscopy analyses. The antitumor efficacy and immune profile of P21 monotherapy, or combined with anti-PD-L1 immune checkpoint inhibitors, were assessed in mouse models bearing CT26.CL25 tumors and 4T1 breast cancer. Results Inhibition of oncogenic miR-21 in cancer cells by P21 efficiently activates tumor suppressor genes, inducing autophagy and endoplasmic reticulum stress. Subsequent cell-death-associated immune activation (immunogenic cell death) is initiated via the release of damage-associated molecular patterns. The in vivo results also illustrated that the immunogenic cell death triggered by P21 could effectively sensitize the immunosuppressive TME. That is, P21 enhances CD8+ T cell infiltration in tumor tissues by conferring immunogenicity to dying cancer cells and promoting dendritic cell maturation. Meanwhile, combining P21 with an anti-PD-L1 immune checkpoint inhibitor elicits a highly potent antitumor effect in a CT26.CL25 tumor-bearing mouse model and 4T1 metastatic tumor model. Conclusions: Collectively, we have clarified a miR-21-related immunogenic cell death mechanism through the precise delivery of anti-miR-21 to the PD-L1high TME. These findings highlight the potential of miR-21 as a target for immunotherapeutic interventions.

Synergistic action of gemcitabine and celecoxib in promoting the antitumor efficacy of anti-programmed death-1 monoclonal antibody by triggering immunogenic cell death.

Background: Emerging evidence suggests that immunogenic chemotherapy not only kills tumor cells but also improves the immune-suppressive tumor microenvironment by inducing immunogenic cell death (ICD), leading to sustained anti-tumor effects. The lack of ICD inducers explored in lung cancer necessitates investigation into new inducers for this context, therefore, this study aims to explore whether the gemcitabine (GEM) and celecoxib can activate the immunogenic chemotherapy progress in lung cancer tissue. Methods: We assessed five chemotherapeutic agents for their ability to trigger ICD using ex vivo and in vivo experiments, including western blotting (WB), flow cytometry, and tumor preventive vaccine assays. Additionally, we evaluated the synergistic effects of GEM, celecoxib, and anti-programmed death 1 monoclonal antibody (aPD-1) in tumor-bearing mice to understand how GEM activates antitumor immunity and enhances immunochemotherapy. Results: GEM was identified as an effective ICD inducer, showing high expression of calreticulin (CRT) and heat shock protein 90 (HSP90). Co-culture with GEM-treated cells [Lewis lung carcinoma (LLC) and CMT-64] enhanced dendritic cell (DC) activity, evidenced by maturation markers and increased phagocytic capacity. Moreover, celecoxib was found to enhance ICD by reducing indoleamine 2,3-dioxygenase 1 (IDO1) expression and increasing reactive oxygen species (ROS)-based endoplasmic reticulum (ER) stress. The combination therapy [GEM, celecoxib, and aPD-1 (GCP)] exhibited potent and sustained antitumor activity in immunocompetent mice, with enhanced recruitment of tumor-infiltrating lymphocytes. Conclusions: These findings support the potential use of GCP therapy as a treatment option for lung cancer patients.

Signature identification based on immunogenic cell death-related lncRNAs to predict the prognosis and immune activity of patients with endometrial carcinoma.

Background: Endometrial carcinoma (EC) is one of the most prevalent gynecologic malignancies and requires further classification for treatment and prognosis. Long non-coding RNAs (lncRNAs) and immunogenic cell death (ICD) play a critical role in tumor progression. Nevertheless, the role of lncRNAs in ICD in EC remains unclear. This study aimed to explore the role of ICD related-lncRNAs in EC via bioinformatics and establish a prognostic risk model based on the ICD-related lncRNAs. We also explored immune infiltration and immune cell function across prognostic groups and made treatment recommendations. Methods: A total of 552 EC samples and clinical data of 548 EC patients were extracted from The Cancer Genome Atlas (TCGA) database and University of California Santa Cruz (UCSC) Xena, respectively. A prognostic-related feature and risk model was developed using the least absolute shrinkage and selection operator (LASSO). Subtypes were classified with consensus cluster analysis and validated with t-Distributed Stochastic Neighbor Embedding (tSNE). Kaplan-Meier analysis was conducted to assess differences in survival. Infiltration by immune cells was estimated by single sample gene set enrichment analysis (ssGSEA), Tumor IMmune Estimation Resource (TIMER) algorithm. Quantitative polymerase chain reaction (qPCR) was used to detect lncRNAs expression in clinical samples and cell lines. A series of studies was conducted in vitro and in vivo to examine the effects of knockdown or overexpression of lncRNAs on ICD. Results: In total, 16 ICD-related lncRNAs with prognostic values were identified. Using SCARNA9, FAM198B-AS1, FKBP14-AS1, FBXO30-DT, LINC01943, and AL161431.1 as risk model, their predictive accuracy and discrimination were assessed. We divided EC patients into high-risk and low-risk groups. The analysis showed that the risk model was an independent prognostic factor. The prognosis of the high- and low-risk groups was different, and the overall survival (OS) of the high-risk group was lower. The low-risk group had higher immune cell infiltration and immune scores. Consensus clustering analysis divided the samples into four subtypes, of which cluster 4 had higher immune cell infiltration and immune scores. Conclusions: A prognostic signature composed of six ICD related-lncRNAs in EC was established, and a risk model based on this signature can be used to predict the prognosis of patients with EC.

INT-1B3, an LNP formulated miR-193a-3p mimic, promotes anti-tumor immunity by enhancing T cell mediated immune responses via modulation of the tumor microenvironment and induction of immunogenic cell death.

microRNAs (miRNAs) are small, non-coding RNAs that regulate expression of multiple genes. MiR-193a-3p functions as a tumor suppressor in many cancer types, but its effect on inducing specific anti-tumor immune responses is unclear. Therefore, we examined the effect of our lipid nanoparticle (LNP) formulated, chemically modified, synthetic miR-193a-3p mimic (INT-1B3) on anti-tumor immunity. INT-1B3 inhibited distant tumor metastasis and significantly prolonged survival. INT-1B3-treated animals were fully protected against challenge with autologous tumor cells even in absence of treatment indicating long-term immunization. Protection against autologous tumor cell challenge was hampered upon T cell depletion and adoptive T cell transfer abrogated tumor growth. Transfection of tumor cells with our miR-193a-3p mimic (1B3) resulted in tumor cell death and apoptosis accompanied by increased expression of DAMPs. Co-culture of 1B3-transfected tumor cells and immature DC led to DC maturation and these mature DC were able to stimulate production of type 1 cytokines by CD4+ and CD8+ T cells. CD4-CD8- T cells also produced type 1 cytokines, even in response to 1B3-transfected tumor cells directly. Live cell imaging demonstrated PBMC-mediated cytotoxicity against 1B3-transfected tumor cells. These data demonstrate for the first time that miR-193a-3p induces long-term immunity against tumor development via modulation of the tumor microenvironment and induction of immunogenic cell death.

Multifunctional Nanoparticle-Loaded Injectable Alginate Hydrogels with Deep Tumor Penetration for Enhanced Chemo-Immunotherapy of Cancer.

Chemo-immunotherapy has become a promising strategy for cancer treatment. However, the inability of the drugs to penetrate deeply into the tumor and form potent tumor vaccines in vivo severely restricts the antitumor effect of chemo-immunotherapy. In this work, an injectable sodium alginate platform is reported to promote penetration of the chemotherapeutic doxorubicin (DOX) and delivery of personalized tumor vaccines. The injectable multifunctional sodium alginate platform cross-links rapidly in the presence of physiological concentrations of Ca2+, forming a hydrogel that acts as a drug depot and releases loaded hyaluronidase (HAase), DOX, and micelles (IP-NPs) slowly and sustainedly. By degrading hyaluronic acid (HA) overexpressed in tumor tissue, HAase can make tumor tissue "loose" and favor other components to penetrate deeply. DOX induces potent immunogenic cell death (ICD) and produces tumor-associated antigens (TAAs), which could be effectively captured by polyethylenimine (PEI) coated IP-NPs micelles and form personalized tumor vaccines. The vaccines efficaciously facilitate the maturation of dendritic cells (DCs) and activation of T lymphocytes, thus producing long-term immune memory. Imiquimod (IMQ) loaded in the core could further activate the immune system and trigger a more robust antitumor immune effect. Hence, the research proposes a multifunctional drug delivery platform for the effective treatment of colorectal cancer.