Tumor Cell Vaccine Research Articles

Mechanotransduction-Piloted Whole-Cell Vaccines for Spatiotemporal Modulation of Postoperative Antitumor Immunity.

Whole tumor cell vaccines hold promise by presenting a broader spectrum of autologous-origin tumor antigens to combat postoperative recurrence and metastasis. However, challenges such as intractable adjuvant modification and obscure interactions with antigen-presenting cells in the postoperative microenvironment impede their translation into effective personalized immunotherapies. In this study, we propose cancer vaccines derived from manganese oxide-immobilized resected tumor cells, featuring whole tumor antigens and adjustable stiffness to modulate interactions with antigen-presenting cells in the postoperative microenvironment. These vaccines effectively stimulate dendritic cell phagocytosis and function through sequential stiffness-mediated mechanotransduction and interferon signaling. We evaluated their efficacy using an orthotopic triple-negative breast cancer mouse model and found that combining the vaccines with radiotherapy effectively inhibits postoperative tumor recurrence and metastasis. Our study underscores the potential of utilizing mechanotransduced adjuvants alongside directly inactivated whole-cell vaccines as a universal solution for preventing postoperative tumor recurrence.

Immunotherapy Vaccines for Prostate Cancer Treatment.

Therapeutic tumor vaccines have emerged as a compelling avenue for treating patients afflicted with advanced prostate cancer (PCa), particularly those experiencing biochemical relapse or ineligible for surgical intervention. This study serves to consolidate recent research findings on therapeutic vaccines targeting prostate tumors while delineating prevalent challenges within vaccine research and development. We searched electronic databases, including PubMed, Web of Science, Embase, and Scopus, up to August 31, 2024, using keywords such as 'vaccine', 'prostate cancer', 'immunotherapy', and others. We reviewed studies on various therapeutic vaccines, including dendritic cell-based, antigen, nucleic acid, and tumor cell vaccines. Studies consistently showed that therapeutic vaccines, notably DC vaccines, had favorable safety profiles with few adverse effects. These vaccines, with varied antigenic formulations, demonstrated strong clinical outcomes, as indicated by metrics such as PSA response rates (9.5%-58%), extended PSA doubling times (52.9%-89.7%), overall survival durations (17.7-33.8 months), two-year mortality rates (0%-12.5%), biochemical relapse rates (42%-73%), and antigen-specific immune responses (33.3%-71.4% in responsive groups). While clinical data for tumor vaccines have illuminated robust evidence of tumoricidal activity, the processes of their formulation and deployment are riddled with complexities. Combining vaccines with other therapies may enhance outcomes, and future research should focus on early interventions and deciphering the immune system's role in oncogenesis.

The Mechanisms of Immune Evasion in Cancer Stem Cells and Related Immunotherapy Advances

Cancer Stem Cells (CSCs), as a unique subset of tumor cells, play a crucial role in tumor initiation, progression, and recurrence due to their self-renewal and differentiation capabilities. CSCs exhibit significant immune evasion abilities, allowing them to escape host immune surveillance, leading to the failure of conventional treatments. This paper reviews the definition, characteristics, and immune evasion mechanisms of CSCs, including immune checkpoint pathways, immunosuppressive microenvironment, and changes in surface antigen expression. Additionally, it explores various immunotherapies targeting CSCs, such as immune checkpoint inhibitors, CAR-T cell therapy, tumor vaccines, and other emerging therapies, discussing their research progress and clinical application prospects. By comprehensively understanding the immune evasion mechanisms of CSCs and related immunotherapies, we aim to provide new insights and strategies for future cancer treatments.

The progress of tumor vaccines clinical trials in non-small cell lung cancer.

Non-small cell lung cancer (NSCLC) remains a significant global health challenge, with high mortality rates and limited treatment options. Tumor vaccines have emerged as a potential therapeutic approach, aiming to stimulate the immune system to specifically target tumor cells. This study screened 283 clinical trials registered on ClinicalTrials.gov through July 31, 2023. After excluding data that did not meet the inclusion criteria, a total of 108 trials were assessed. Data on registered number, study title, study status, vaccine types, study results, conditions, interventions, outcome measures, sponsor, collaborators, drug target, phases, enrollment, start date, completion date and locations were extracted and analyzed. The number of vaccines clinical trials for NSCLC has continued to increase in recent years, the majority of which were conducted in the United States. Most of the clinical trials were at stages ranging from Phase I to Phase II. Peptide-based vaccines accounted for the largest proportion. Others include tumor cell vaccines, DNA/RNA vaccines, viral vector vaccines, and DC vaccines. Several promising tumor vaccine candidates have shown encouraging results in early-phase clinical trials. However, challenges such as heterogeneity of tumor antigens and immune escape mechanisms still need to be addressed. Tumor vaccines represent a promising avenue in the treatment of NSCLC. Ongoing clinical trials are crucial for optimizing vaccine strategies and identifying the most effective combinations. Further research is needed to overcome existing limitations and translate these promising findings into clinical practice, offering new hope for NSCLC patients.

Abstract CT134: Safety and immunologic impact of neoadjuvant/adjuvant GM-CSF-secreting allogenic pancreatic tumor cell vaccine (GVAX) combined with cyclophosphamide, pembrolizumab, and macrophage-targeting CSF1R inhibitor IMC-CS4 in pancreatic adenocarcinoma

Abstract Background: Strategies are needed to improve effectiveness of immunotherapy in pancreatic ductal adenocarcinoma (PDA). Our recently published study (NCT02648282) showed that increased M1/M2 ratio and decreased PDL1+ M2-like tumor associated macrophages (TAM) in locally advanced PDA is associated with longer overall survival (OS) following combination of stereotactic body radiotherapy, GVAX and anti-PD1 antibody pembrolizumab (Pem). We hypothesized targeting M2-like macrophages, regulated by the colony stimulating factor-1 (CSF1) pathway, would improve outcomes. In this pilot study we investigated the safety and intratumoral immune response of neoadjuvant/adjuvant triplet immunotherapy: GVAX/cyclophosphamide (CY), Pem, and CSF1 receptor blockade (IMC-CS4) in patients with resectable or borderline resectable PDA. Methods: After completing chemotherapy and radiation patients received two 3-week cycles of neoadjuvant triplet immunotherapy. Following surgery, patients received 4 additional cycles followed by booster Pem every 3 weeks and GVAX/CY every 6 months, for one year. Co-primary endpoints were safety, assessed by NCI Common Terminology Criteria for Adverse Events (AEs), and immune response (increased CD8+ T-cell density in surgical specimen as compared to pre-treatment core). Secondary endpoints included disease free survival (DFS), OS, surgical resectability, and pathologic response (PR). Results: Nine patients were enrolled. Two immune related grade 3/4 AEs (diarrhea and rash) were reported. Median DFS was 12.6 months (95% CI: 7.3, NR) and median OS was 20.4 months (95% CI: 17.5, NR). All patients underwent surgery with major PR rate of 78% (defined as <10% residual viable tumor), including one complete PR. Comparing paired biopsies, the study met its primary immunologic endpoint showing 6/8 patients (75%) had a >80% increase of CD8+ T cells; the increase was at least 1.8 times the baseline median absolute deviation following triple therapy (p=0.012). There was a significant increase of Granzyme B+ CD8+ T cells among all patients (p=0.045). No significant change in myeloid cell density, including TAM, was observed, suggesting IMC-CS4 did not deplete macrophages, but potentially reprogrammed them. The 4 patients with greatest drop in CD66b+ granulocyte levels had major PR (grade 0 or 1). Conclusion: The triplet was safe and significantly increased activated CD8+ T cells suggesting the combination can induce an effector T cell response. Decreased granulocyte levels correlated with PR. Citation Format: Arielle Urman, Yingjun Ding, Hao Wang, Richard A. Burkhart, Jin He, Elizabeth M. Jaffee, Amol K. Narang, Dung Le, Daniel A. Laheru, Lei Zheng, Ana De Jesus-Acosta. Safety and immunologic impact of neoadjuvant/adjuvant GM-CSF-secreting allogenic pancreatic tumor cell vaccine (GVAX) combined with cyclophosphamide, pembrolizumab, and macrophage-targeting CSF1R inhibitor IMC-CS4 in pancreatic adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT134.

Metal-Phenolic Nanocloaks on Cancer Cells Potentiate STING Pathway Activation for Synergistic Cancer Immunotherapy.

Due to the presence of natural neoantigens, autologous tumor cells hold great promise as personalized therapeutic vaccines. Yet autologous tumor cell vaccines require multi-step production that frequently leads to the loss of immunoreactive antigens, causing insufficient immune activation and significantly hampering their clinical applications. Herein, we introduce a novel whole-cell cancer vaccine by cloaking cancer cells with lipopolysaccharide-decorated manganese(II)-phenolic networks (MnTA nanocloaks) to evoke tumor-specific immune response for highly efficacious synergistic cancer immunotherapy. The natural polyphenols coordinate with Mn2+ and immediately adhere to the surface of individual cancer cells, thereby forming a nanocloak and encapsulating tumor neoantigens. Subsequent decoration with lipopolysaccharide induces internalization by dendritic cells, where Mn2+ ions are released in the cytosol, further facilitating the activation of the stimulator of the interferon genes (STING) pathway. Highly effective tumor suppression was observed by combining the nanocloaked cancer cell treatment with anti-programmed cell death ligand 1 (anti-PD-L1) antibodies-mediated immune checkpoint blockade therapy. Our work demonstrates a universal yet simple strategy to engineer a cell-based nanobiohybrid system for enhanced cancer immunotherapy.

Metal‐Phenolic Nanocloaks on Cancer Cells Potentiate STING Pathway Activation for Synergistic Cancer Immunotherapy

AbstractDue to the presence of natural neoantigens, autologous tumor cells hold great promise as personalized therapeutic vaccines. Yet autologous tumor cell vaccines require multi‐step production that frequently leads to the loss of immunoreactive antigens, causing insufficient immune activation and significantly hampering their clinical applications. Herein, we introduce a novel whole‐cell cancer vaccine by cloaking cancer cells with lipopolysaccharide‐decorated manganese(II)‐phenolic networks (MnTA nanocloaks) to evoke tumor‐specific immune response for highly efficacious synergistic cancer immunotherapy. The natural polyphenols coordinate with Mn2+ and immediately adhere to the surface of individual cancer cells, thereby forming a nanocloak and encapsulating tumor neoantigens. Subsequent decoration with lipopolysaccharide induces internalization by dendritic cells, where Mn2+ ions are released in the cytosol, further facilitating the activation of the stimulator of the interferon genes (STING) pathway. Highly effective tumor suppression was observed by combining the nanocloaked cancer cell treatment with anti‐programmed cell death ligand 1 (anti‐PD‐L1) antibodies‐mediated immune checkpoint blockade therapy. Our work demonstrates a universal yet simple strategy to engineer a cell‐based nanobiohybrid system for enhanced cancer immunotherapy.

Photodynamic Therapy Derived Personalized Whole Cell Tumor Vaccine Prevents Postsurgery Tumor Recurrence and Metastasis.

In order to avoid the time-consuming and laborious identification of tumor-specific antigens (TSAs) during the traditional vaccine fabrication process, a versatile photodynamic therapy (PDT)-based method is developed to construct a whole-tumor antigen tumor vaccine (TV) from surgically resected tumor tissues for personalized immunotherapy. Mucoadhesive nanoparticles containing small-molecular photosensitizer are fabricated and directly co-incubated with suspended tumor cells obtained after cytoreduction surgery. After irradiation with a 405nm laser, potent immunogenic cell death of cancer cells could be induced. Along with the release of TSAs, the as-prepared TV could activate safe and robust tumor-specific immune responses, leading to efficient suppression of postsurgery tumor recurrence and metastasis. The as-prepared TV cannot only be applied alone through various administration routes but also synergize with immunoadjuvant, chemotherapeutics, and immune checkpoint blockers to exert more potent immune responses. This work provides an alternative way to promote the clinical translation of PDT, which is generally restricted by the limited penetration of light. Moreover, the versatile strategy of vaccine fabrication also facilitates the clinical application of personalized whole-cell tumor vaccines.

Allogeneic "Zombie Cell" as Off-The-Shelf Vaccine for Postsurgical Cancer Immunotherapy.

Allogeneic tumor cell vaccines provide off-the-shelf convenience but lack patient specificity due to heterogeneity in tumor antigens. Here, allogeneic tumor cell corpses are converted into "zombie cells" capable of assimilating heterogeneous tumor by seizing cancer cells and spreading adjuvant infection. This causes pseudo-oncolysis of tumors, transforming them into immunogenic targets for enhanced phagocytosis. It is shown that in postoperative tumor models, localized delivery of premade "zombie cells" through stepwise gelation in resection cavity consolidates tumor surgery. Compared to analogous vaccines lacking "seizing" or "assimilating" capability, "zombie cell" platform effectively mobilizes T cell response against residual tumors, and establishes immunological memory against tumor re-challenge, showing less susceptibility to immune evasion. Despite using allogeneic sources, "zombie cell" platform functions as generalizable framework to produce long-term antitumor immunity in different tumor models, showing comparable effect to autologous vaccine. Together, with the potential of off-the-shelf availability and personalized relevance to heterogenous tumor antigens, this study suggests an alternative strategy for timely therapy after tumor surgery.

Therapeutic Vaccines in Breast Cancer

Breast cancer (BC) is a major worldwide health issue, characterised by an increasing occurrence in both males and females. The classification of breast cancer subgroups is determined by variations in hormone receptor expression. Although traditional breast cancer therapies, including chemotherapy, surgery, and radiotherapy, have demonstrated effectiveness in the treatment of patients, they are frequently associated with significant adverse effects and recurrence. The emergence of therapeutic vaccines has become a promising option for the field of immunotherapy. These vaccines enhance the body’s immune system to identify and eliminate cancerous tumour cells. The current approach to vaccine therapy for breast cancer focuses on the targeting of two main categories of antigens: tumour associated antigens and tumour specific antigens. Excitingly, multiple vaccine strategies for breast cancer treatment have been employed, all of which have demonstrated promise and effectiveness in clinical studies. Currently, proposed vaccine types include peptide-based vaccines, whole tumour cell vaccines, DNA/RNA-based vaccines, dendritic cell vaccines, and viral-vector vaccines, etc. This review examined the present state of different types of vaccines in breast cancer therapy, including the therapeutic mechanism and the treatment outcomes.

Regulation of cancer stem cells and immunotherapy of glioblastoma (Review).

Glioblastoma (GB) is one of the most adverse diagnoses in oncology. Complex current treatment results in a median survival of 15 months. Resistance to treatment is associated with the presence of cancer stem cells (CSCs). The present review aimed to analyze the mechanisms of CSC plasticity, showing the particular role of β-catenin in regulating vital functions of CSCs, and to describe the molecular mechanisms of Wnt-independent increase of β-catenin levels, which is influenced by the local microenvironment of CSCs. The present review also analyzed the reasons for the low effectiveness of using medication in the regulation of CSCs, and proposed the development of immunotherapy scenarios with tumor cell vaccines, containing heterogenous cancer cells able of producing a multidirectional antineoplastic immune response. Additionally, the possibility of managing lymphopenia by transplanting hematopoietic stem cells from a healthy sibling and using clofazimine or other repurposed drugs that reduce β-catenin concentration in CSCs was discussed in the present study.

IMMU-51. THE LANDSCAPE OF TUMOR INFILTRATING T CELLS (TILS) OF CHILDHOOD BRAIN TUMORS

Abstract T lymphocytes have a unique ability to recognize a vast array of antigens prompt by an enormous T cell receptor (TCR) repertoire. Characterization of tumor-infiltrating T cells (TILs) and their TCRs is key to understand MHC-restricted anti-tumor immunity and for developing T cell centered immunotherapies such as adoptive cell therapy and tumor vaccines. In the current work, we investigated RNAseq data from nearly 1,000 pediatric brain tumor patients and performed the first large-scale comprehensive examination of the immunogenomic and TCR landscape of TILs across the spectrum of pediatric brain tumors. We show that the relative ratio between T cell diversity (clonality) and T cell abundance within each sample, represented by the clonal expansion index (CEI), is a strong predictor of prognosis across tumor types and molecular subtypes. Interestingly, we found that CEI was strongly associated with molecular subgroups of medulloblastoma but not with known genomic features of these subgroups. Analysis of single-cell (sc)RNAseq and scTCRseq data of TILs across several tumor types, validated clonal expansion of TILs which were frequently associated with effector-cytotoxic T cell phenotypes, whereas non-expanded TILs were associated mostly with CD4 T cell phenotypes. Investigation of T cell clones recognizing a common recurrent tumor-antigen across patients based on CDR3 homology and characteristics, reveals several T cell specificity groups which are tumor type restricted with defined HLA dominance. Using machine learning investigations of genomic profiles of the patients which contain these T cell specificity groups identified novel putative HLA-restricted tumor antigens shared across patients. Importantly, our framework grounded the foundations for developing a precision medicine approach of T cell centered immunotherapies. In all, our findings have major implications for understanding the interplay between T cell and tumor genomic, and for improving immunotherapy strategies for childhood brain tumors.

Echinococcus granulosus as a Promising Therapeutic Agent against Triplenegative Breast Cancer

Abstract:Breast cancer is a major cause of cancer deaths in women, with approximately 1.2 million new cases per year. Current treatment options for breast cancer include surgery, radiation, hormone therapy, and chemotherapy. However, the non-selective cytotoxicity of chemotherapeutic agents often leads to severe side effects, while drug resistance can worsen patient outcomes. Therefore, the development of more effective and less toxic anticancer drugs is a critical need. This study aimed to review the literature on Echinococcus granulosus antigens with anticancer potential against triple-negative breast cancer. Recent studies have suggested that certain parasite antigens may have potential anticancer effects. Specifically, research has shown that echinococcosis, a disease caused by the parasitic cestode Echinococcus granulosus, may have a protective effect against cancer. These findings offer new insights into the potential use of E. granulosus antigens in the development of novel cancer therapies and tumor cell vaccines. The findings of recent studies suggested that E. granulosus antigens may have the potential to be used in effective and less toxic cancer treatments. However, further research is needed to fully understand the mechanisms behind the anticancer effects of these antigens and develop new cancer therapies and vaccines

APR-246 increases tumor antigenicity independent of p53.

We previously reported that activation of p53 by APR-246 reprograms tumor-associated macrophages to overcome immune checkpoint blockade resistance. Here, we demonstrate that APR-246 and its active moiety, methylene quinuclidinone (MQ) can enhance the immunogenicity of tumor cells directly. MQ treatment of murine B16F10 melanoma cells promoted activation of melanoma-specific CD8+ T cells and increased the efficacy of a tumor cell vaccine using MQ-treated cells even when the B16F10 cells lacked p53. We then designed a novel combination of APR-246 with the TLR-4 agonist, monophosphoryl lipid A, and a CD40 agonist to further enhance these immunogenic effects and demonstrated a significant antitumor response. We propose that the immunogenic effect of MQ can be linked to its thiol-reactive alkylating ability as we observed similar immunogenic effects with the broad-spectrum cysteine-reactive compound, iodoacetamide. Our results thus indicate that combination of APR-246 with immunomodulatory agents may elicit effective antitumor immune response irrespective of the tumor's p53 mutation status.

Brentuximab Vedotin-Driven Microtubule Disruption Results in Endoplasmic Reticulum Stress Leading to Immunogenic Cell Death and Antitumor Immunity.

Brentuximab vedotin, a CD30-directed antibody-drug conjugate (ADC), is approved for clinical use in multiple CD30-expressing lymphomas. The cytotoxic payload component of brentuximab vedotin is monomethyl auristatin E (MMAE), a highly potent microtubule-disrupting agent. Preclinical results provided here demonstrate that treatment of cancer cells with brentuximab vedotin or free MMAE leads to a catastrophic disruption of the microtubule network eliciting a robust endoplasmic reticulum (ER) stress response that culminates in the induction of the classic hallmarks of immunogenic cell death (ICD). In accordance with the induction of ICD, brentuximab vedotin-killed lymphoma cells drove innate immune cell activation in vitro and in vivo. In the "gold-standard" test of ICD, vaccination of mice with brentuximab vedotin or free MMAE-killed tumor cells protected animals from tumor rechallenge; in addition, T cells transferred from previously vaccinated animals slowed tumor growth in immunodeficient mice. Immunity acquired from killed tumor cell vaccination was further amplified by the addition of PD-1 blockade. In a humanized model of CD30+ B-cell tumors, treatment with brentuximab vedotin drove the expansion and recruitment of autologous Epstein-Barr virus-reactive CD8+ T cells potentiating the activity of anti-PD-1 therapy. Together, these data support the ability of brentuximab vedotin and MMAE to drive ICD in tumor cells resulting in the activation of antigen-presenting cells and augmented T-cell immunity. These data provide a strong rationale for the clinical combination of brentuximab vedotin and other MMAE-based ADCs with checkpoint inhibitors.

Generation of whole tumor cell vaccine for on-demand manipulation of immune responses against cancer under near-infrared laser irradiation

The therapeutic efficacy of whole tumor cell vaccines (TCVs) is modest, which has delayed their translation into personalized immunotherapies in the clinic. Here, we develop a TCV platform based on photothermal nanoparticle-loaded tumor cells, which can be rationally applied to diverse tumor types to achieve on-demand boost of anti-tumor immune responses for inhibiting tumor growth. During the fabrication process, mild photothermal heating by near-infrared (NIR) laser irradiation induces the nanoparticle-bearing tumor cells to express heat shock proteins as endogenous adjuvants. After a single vaccination at the back of tumor-bearing mice, non-invasive NIR laser irradiation further induces mild hyperthermia at vaccination site, which promotes the recruitment, activation, and antigen presentation by dendritic cells. Using an indicator we term fluctuation of tumor growth rate, we determine appropriate irradiation regimens (including optimized irradiation intervals and times). This TCV platform enables on-demand NIR manipulation of immune responses, and we demonstrate potent therapeutic efficacy against six murine models that mimick a range of clinical scenarios, including a model based on humanized mice and patient-derived tumor xenografts.

RWTC-MBTA: autologous vaccine prevents metastases via antitumor immune responses

BackgroundAutologous tumor cell-based vaccines (ATVs) aim to prevent and treat tumor metastasis by activating patient-specific tumor antigens to induce immune memory. However, their clinical efficacy is limited. Mannan-BAM (MB), a pathogen-associated molecular pattern (PAMP), can coordinate an innate immune response that recognizes and eliminates mannan-BAM-labeled tumor cells. TLR agonists and anti-CD40 antibodies (TA) can enhance the immune response by activating antigen-presenting cells (APCs) to present tumor antigens to the adaptive immune system. In this study, we investigated the efficacy and mechanism of action of rWTC-MBTA, an autologous whole tumor cell vaccine consisting of irradiated tumor cells (rWTC) pulsed with mannan-BAM, TLR agonists, and anti-CD40 antibody (MBTA), in preventing tumor metastasis in multiple animal models.MethodsThe efficacy of the rWTC-MBTA vaccine was evaluated in mice using breast (4T1) and melanoma (B16-F10) tumor models via subcutaneous and intravenous injection of tumor cells to induce metastasis. The vaccine’s effect was also assessed in a postoperative breast tumor model (4T1) and tested in autologous and allogeneic syngeneic breast tumor models (4T1 and EMT6). Mechanistic investigations included immunohistochemistry, immunophenotyping analysis, ELISA, tumor-specific cytotoxicity testing, and T-cell depletion experiments. Biochemistry testing and histopathology of major tissues in vaccinated mice were also evaluated for potential systemic toxicity of the vaccine.ResultsThe rWTC-MBTA vaccine effectively prevented metastasis and inhibited tumor growth in breast tumor and melanoma metastatic animal models. It also prevented tumor metastasis and prolonged survival in the postoperative breast tumor animal model. Cross-vaccination experiments revealed that the rWTC-MBTA vaccine prevented autologous tumor growth, but not allogeneic tumor growth. Mechanistic data demonstrated that the vaccine increased the percentage of antigen-presenting cells, induced effector and central memory cells, and enhanced CD4+ and CD8+ T-cell responses. T-cells obtained from mice that were vaccinated displayed tumor-specific cytotoxicity, as shown by enhanced tumor cell killing in co-culture experiments, accompanied by increased levels of Granzyme B, TNF-α, IFN-γ, and CD107a in T-cells. T-cell depletion experiments showed that the vaccine’s antitumor efficacy depended on T-cells, especially CD4+ T-cells. Biochemistry testing and histopathology of major tissues in vaccinated mice revealed negligible systemic toxicity of the vaccine.ConclusionThe rWTC-MBTA vaccine demonstrated efficacy in multiple animal models through T-cell mediated cytotoxicity and has potential as a therapeutic option for preventing and treating tumor metastasis with minimal systemic toxicity.

Dying tumor cells-inspired vaccine for boosting humoral and cellular immunity against cancer.

Whole tumor cells can act as effective antigen depots and have been regarded as prospective candidate for cancer vaccines. However, the clinical outcomes of whole tumor cell vaccine were restricted by the poor immunogenicity and potential in vivo oncogenicity risks. Herein, a simple and effective cancer vaccine named frozen dying tumor cells (FDT) was constructed to initiate a cascade of immune attacks against cancer. By introducing immunogenic dying tumor cells and integrating cryogenic freezing technology, FDT was endowed with high immunogenicity, good in vivo safety, and long-time storage superiority. In syngeneic mice with malignant melanoma, FDT primed the polarization of follicular helper T cells and the differentiation of germinal center B cells in lymph nodes, and promoted the infiltration of cytotoxic CD8+ T cells in the tumor microenvironment, triggering the dual activation of humoral and cellular immunity. Of note, when combined with cytokines and immune checkpoint inhibitors, the FDT vaccine achieved 100% eradication of pre-existing tumors in mice, as demonstrated in the peritoneal metastasis model of colorectal carcinoma. Taken together, our work suggests an efficient cancer vaccine inspired by dying tumor cells and provides an alternative treatment candidate for cancer.

Whole tumour cell-based vaccines: tuning the instruments to orchestrate an optimal antitumour immune response.

Immunotherapy, particularly those based on immune checkpoint inhibitors (ICIs), has become a useful approach for many neoplastic diseases. Despite the improvements of ICIs in supporting tumour regression and prolonging survival, many patients do not respond or develop resistance to treatment. Thus, therapies that enhance antitumour immunity, such as anticancer vaccines, constitute a feasible and promising therapeutic strategy. Whole tumour cell (WTC) vaccines have been extensively tested in clinical studies as intact or genetically modified cells or tumour lysates, injected directly or loaded on DCs with distinct adjuvants. The essential requirements of WTC vaccines include the optimal delivery of a broad battery of tumour-associated antigens, the presence of tumour cell-derived molecular danger signals, and adequate adjuvants. These factors trigger an early and robust local innate inflammatory response that orchestrates an antigen-specific and proinflammatory adaptive antitumour response capable of controlling tumour growth by several mechanisms. In this review, the strengths and weaknesses of our own and others' experiences in studying WTC vaccines are revised to discuss the essential elements required to increase anticancer vaccine effectiveness.

CD24-Fc suppression of immune related adverse events in a therapeutic cancer vaccine model of murine neuroblastoma.

The combination of Myc-suppressed whole tumor cells with checkpoint inhibitors targeting CTLA-4 and PD-L1 generates a potent therapeutic cancer vaccine in a mouse neuroblastoma model. As immunotherapies translate from pre-clinical to clinical trials, the potential immune-related adverse events (irAEs) associated with induction of potent immunity must be addressed. The CD24-Siglec 10/G interaction is an innate checkpoint that abrogates inflammatory responses to molecules released by damaged cells, but its role in cancer immunology is not well defined. We investigate irAEs of an effective whole cell neuroblastoma vaccine and subsequently the effect of CD24-Fc, a CD24 and Fc fusion protein, on both the vaccine efficacy and induced irAEs in a mouse neuroblastoma model. To test whether the whole tumor cell vaccination leads to autoimmune responses in other organ systems we harvested lung, heart, kidney and colon from naïve mice (n=3), unvaccinated tumor only mice (n=3), and vaccinated mice with CD24 Fc (n=12) or human IgG-Fc control (n=12) after tumor inoculation and vaccination therapy at day 30. The Immune cell infiltrates and immunogenic pathway signatures in different organ systems were investigated using NanoString Autoimmune Profiling arrays. Nanostring RNA transcript results were validated with immunohistochemistry staining. The whole tumor cell vaccine combined with immune checkpoint therapy triggers occult organ specific immune cell infiltrates, primarily in cardiac tissue and to a lesser extent in the renal and lung tissue, but not in the colon. CD24-Fc administration with vaccination partially impedes anti-tumor immunity but delaying CD24-Fc administration after initial vaccination reverses this effect. CD24-Fc treatment also ameliorates the autoimmune response induced by effective tumor vaccination in the heart. This study illustrates that the combination of Myc suppressed whole tumor cell vaccination with checkpoint inhibitors is an effective therapy, but occult immune infiltrates are induced in several organ systems in a mouse neuroblastoma model. The systemic administration of CD24-Fc suppresses autoimmune tissue responses, but appropriate timing of administration is critical for maintaining efficacy of the therapeutic vaccine.