Antigens For Cancer Immunotherapy Research Articles

Advancements in the Application of Proteogenomic in Assisting the Discovery of Novel Cancer Antigens

Over 18.1 million patients worldwide affected by more than 100 different types of cancer. Cancer is one of the critical focuses of medical research today. Researchers have discovered numerous types of cancer, with many patients and a lack of effective unified treatment methods. Therefore, it is urgent to study the pathogenesis and treatment methods. Proteogenomic is an interdisciplinary field focusing on genomics, transcriptomics, and proteomics, which has shown significant effectiveness in tumor analysis and treatment development. Its comprehensive analysis capabilities can help scientists and physicians accurately discover, predict, and treat cancer. This article summarizes the relevant content of using proteogenomic in analyzing and treating various cancers in recent years. It explores the role of proteogenomic in assisting the discovery of new antigens for cancer immunotherapy. This review highlights the latest advancements in proteogenomic and its significant findings in cancer analysis and treatment, suggesting a promising future for its integration into clinical practice.

An effective peptide vaccine strategy circumventing clonal MHC heterogeneity of murine myeloid leukaemia

BackgroundTherapeutic cancer vaccines are an attractive approach for treating malignant tumours, and successful tumour eradication depends primarily on controlling tumour immunosuppression status as well as heterogeneity of tumour cells driven by epigenetic alterations.MethodsPeptide-loaded dendritic cell (DC) prime and non-infectious peptide booster heterologous immunisations were assessed for the immunogenicity of polo-like kinase-1 (PLK1)-derived peptides. Heterologous vaccination regimen targeting multiple shared tumour antigens simultaneously with PD-L1 blockade was assessed against murine myeloid leukaemia.ResultsA synthetic PLK1122 (DSDFVFVVL)-based heterologous vaccination generated large numbers of long-lasting antigen-specific CD8 T-cells eliciting therapeutic effects against various established tumours. The therapeutic efficacy of single antigen-targeting PLK1122-based vaccine with sufficient endurance of PD-L1 blockade toward C1498 leukaemia relied on the heterogeneous clonal levels of MHC-I and PD-L1 expression. A novel multi-peptide-based vaccination targeting PLK1 and survivin simultaneously along with PD1 blockade led to complete tumour eradication and long-term survival in mice with clonally heterologous C1498 myeloid leukaemia.ConclusionsOur findings suggest that PLK1 could be an attractive immunotherapeutic target antigen for cancer immunotherapy, and that similar strategies would be applicable for the optimisation of cancer vaccines for the treatment of numerous viral diseases and malignant tumours.

Abstract 3218: Anti-PD1 and -CTLA-4 combination in vivo enhances DC-based tumor-associated mitochondria antigen immunotherapy efficacy

Abstract Somatic mitochondria DNA (mtDNA) abnormalities have been identified in various types of human cancers. Previously, we generated tumor protective immunity under prophylactic and therapeutic approaches employing a murine kidney tumor model system and dendritic cell (DC)-based vaccination containing RENCA-derived mitochondria enriched lysates. Our results shown that tumor-associated mitochondria antigens (TAMAs) are targetable antigens for cancer immunotherapy (PMID: 26378078). Preliminary data also revealed increased endogenous PD-L1 mRNA expression levels in RENCA tumors of treated mice versus healthy kidney tissue. To investigate the impact of PD1/PD-L1 axis antagonism, Balb/C mice were challenged with RENCA cells at day 0 followed by TAMA-vaccination at day 3 and concurrent administration of anti-PD1 (aPD1) 5 times every 3 days. Interestingly, the aPD1-TAMA treatment resulted in reduced tumor growth, greater T CD4+ and T CD8+ cell infiltration, and lower intratumoral-MDSC as compared to the TAMA vaccine alone. In addition, we observed higher T cell activation from the aPD1-TAMA group upon co-culture with bone marrow-derived dendritic cells exposed to RENCA mitochondria lysate, suggesting that the inhibition of PD1 also enhanced the immunogenicity of the TAMA vaccine. Further analysis of the tumor environment revealed that the PD1-PD-L1 axis antagonism correlated with an increment of intratumoral CTLA4 expression and recruitment of T regulatory (Treg) cells. We introduced a third arm of treatment including a CTLA4 antagonist antibody in combination with aPD1 and TAMA vaccine in vivo. Strikingly, the tumor progression was greatly impacted causing tumor rejection in the majority of tumor-bearing animals, sustained tumor volume reduction in the others, a decrease in Treg cell recruitment, and concomitant increment of T CD8+ cell infiltration and activation. Altogether, the combination of check point inhibitors in vivo significantly improved the efficacy of the TAMA immunotherapy by remodeling the tumor microenvironment, reducing the immunosuppressive potential, and facilitating the infiltration of effector T cells into the tumor. Citation Format: Renzo F. Perales-Linares, Stefano Pierini, Mireia Uribe, Sergei Pustylnikov, Francesca Costabile, Silvia Beghi, Andrea Facciabene. Anti-PD1 and -CTLA-4 combination in vivo enhances DC-based tumor-associated mitochondria antigen immunotherapy efficacy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3218.

The anti-tumor effect of oral cancer vaccine using Bifidobacterium as a platform for displaying Wilms’ tumor 1 protein.

72 Background: The gut microbiota plays an important role in shaping systemic immune responses. We have developed a WT1 oral cancer vaccine using a recombinant Bifidobacterium Longum ( B. Longum) as a platform for displaying murine WT1 protein ( B. Longum-mWT1). The Wilms’ tumor 1 (WT1) gene, which encodes a zinc finger transcription factor, is reportedly overexpressing in various tumors and one of the most promising tumor-associated antigens for cancer immunotherapy. In order to examine anti-tumor effects of this oral vaccine, we administered it orally into mice inoculated with WT1+-expressing brain tumor which doesn’t respond to existing treatment. Methods: The synthesized murine-WT1 gene (117-439 amino acid residues) was fused to galacto-N-biose/lacto-N-biose I binding protein (GLBP) coding gene. GLBP is a membrane protein on the wild-type B. Longum cell wall, which is used as an anchor to display antigen. The resulting plasmid carrying GLBP-WT1 was introduced into B. Longum by electroporation. We inoculated mouse glioma cell lines (Gl261) subcutaneously into the C57BL/6J. C57BL/6J mice received oral administration of B. Longum-mWT1 every day or subcutaneous administration of WT1126 peptide with montanide adjuvant on days 1, 8, 15, 22, 29, and 36. Results: The tumor volume of the mice treated with B. Longum-mWT1 (n = 5) was significantly smaller than that of the mice given WT1 peptide vaccine (n = 5) ( P < 0.05). The frequency of CD8+/WT1-tetramer+ CTLs was higher in B. Longum-mWT1 and WT1 peptide vaccine groups than in PBS group, and the high frequency was maintained in B. Longum-mWT1 group. In the mouse with B. Longum-mWT1, the frequency CD8+/WT1-tetramer+ CTLs in mesenteric lymph node and spleen was higher than that in Peyer’s patch. The number of invasive CD8+ T cells in brain tumor was higher in the B. Longum-mWT1 group than in the PBS group. B. Longum-mWT1 induced significantly higher in vitro cytotoxicity against Gl261 cells than WT1 peptide. Conclusions: We confirmed that B. Longum-mWT1 can induce strong cellular immunity and the maintenance of this effect. These results suggest that it is a novel oral anti-cancer agent for treating glioblastoma, for which no effective treatment has been developed.

Delivery of Cancer-Testis Antigens Using Self-Assembled Dipeptide Nanotubes Inhibits Tumor Growth in Mice Melanoma Model

Delivery of tumor-associated antigens for cancer immunotherapy is generally limited due to poor stability and low cellular uptake. Use of nanoparticles as delivery vehicles has been an exciting development but toxicity associated with nanoparticles has remained a concern. Here, we have used conformationally constraint self-assembling dipeptide nanotubes for the delivery of Cancer-Testis antigens (CTAs). A dipeptide Phenylalanine-α, β-dehydrophenylalanine (F-ΔF) was synthesized and was found to self-assemble into nanotubes. CTAs (NY-ESO-1 and MAGE-3) were also synthesized and loaded onto F-ΔF nanotubes using physical adsorption method for delivery purposes. CTA loaded F-ΔF nanotubes showed higher cellular uptake in macrophages. In animal studies, F-ΔF-CTA nanocomplex elicited much higher immune response compared to CTAs alone and showed an inhibition of ~65-70% tumor growth in mouse melanoma model. Our results indicated that F-ΔF nanotubes are biocompatible and are efficient delivery vehicles for CTAs in vivo and therefore are excellent candidates for further development as delivery agents.

"Minimalist" Nanovaccine Constituted from Near Whole Antigen for Cancer Immunotherapy.

One of the major challenges in vaccine design has been the over dependence on incorporation of abundant adjuvants, which in fact is in violation of the "minimalist" principle. In the present study, a compact nanovaccine derived from a near whole antigen (up to 97 wt %) was developed. The nanovaccine structure was stabilized by free cysteines within each antigen (ovalbumin, OVA), which were tempospatially exposed and heat-driven to form an extensive intermolecular disulfide network. This process enables the engineering of a nanovaccine upon integration of the danger signal (CpG-SH) into the network during the synthetic process. The 50 nm-sized nanovaccine was developed comprising approximately 500 antigen molecules per nanoparticle. The nanovaccine prophylactically protected 70% of mice from tumorigenesis (0% for the control group) in murine B16-OVA melanoma. Significant tumor inhibition was achieved by strongly nanovaccine-induced cytotoxic T lymphocytes. This strategy can be adapted for the future design of vaccine for a minimalist composition in clinical settings.

Abstract 1324: A translational platform to design antibodies targeting triple negative breast cancer-specific antigens for cancer immunotherapy

Abstract Triple negative breast cancers (TNBCs) are characterised by the lack of estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 (HER2) rendering them insensitive to current endocrine and anti-HER2 therapies, therefore novel treatment options are required. Breast cancers have been shown to be immunogenic and patient tumors feature infiltrating immune cells. Since monoclonal antibodies are an important therapeutic modality in the clinical management of many cancers, engineering antibodies against triple negative breast cancer specific antigens that may activate immune effector cells within tumors and in the circulation may lead to tumour clearance and may provide new treatment strategies for this patient group. Here we describe a platform for selection of TNBC-associated antigens, engineering of novel antibodies against these antigens and functional studies to elucidate antibody mechanisms of action and therapeutic potential in vitro and vivo. Our approach involves identification of tumour-associated antigens from patient tumor specimens using a transcriptomics approach and validation and evaluation of biological functions in breast cancer cells using cell culture models. Antibody heavy (VH) and light (VL) sequences are cloned in a dual expression vector system for recombinant expression in HEK293 cells to rapidly produce antibodies with reactivity to specific tumor antigens. The system is optimised for the seamless expression of V genes of any species including human sequences, along with human constant (C) genes of different antibody classes and subclasses. The latter permits the study of different class/subclass antibodies in order to identify those most effective in triggering immune cell activation and tumor clearance. Engineered monoclonal antibodies are subsequently tested for their antigen binding properties and capacity to activate immune effector cells against cancer cells in vitro. The therapeutic potential of selected candidates is evaluated in vivo using xenograft TNBC mouse models engrafted with components of the human immune system using adoptive transfer of healthy volunteer and patient derived peripheral blood cells. Xenograft models featuring human immune components serve to evaluate the therapeutic potential of monoclonal antibodies in the context of their capacity to redirect immune effector functions against cancer cells. Our findings demonstrate a translational pathway designed to facilitate the discovery and evaluation of novel antibody therapeutic options for triple negative breast cancer immunotherapy. Citation Format: Kristina M. Ilieva, Rebecca Marlow, Anthony Cheung, Erika Francesch, Panagiotis Karagiannis, Matthew Fittall, Silvia Crescioli, Andrew Tutt, Sophia Karagiannis. A translational platform to design antibodies targeting triple negative breast cancer-specific antigens for cancer immunotherapy. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1324. doi:10.1158/1538-7445.AM2015-1324

Abstract 2539: Clinical prospective study of PepTivator® WT1-pulsed DC vaccines with assessment of immunological responses in solid tumors

Abstract Wilms' tumor gene 1 (WT1) is reported to be expressed in various types of malignancies and be one of promising target antigens for cancer immunotherapy. However, the synthetic short peptide vaccines based on the WT1 sequences limit a candidate patient by its HLA restriction. In this study, we performed the clinical study for dendritic cell (DC) vaccines using peptide pools consisting mainly of 15-mer sequences with 11 amino acids overlaps of full-length WT1 protein (PepTivator® WT1). We previously reported that copulsing tumor antigen-pulsed DC with zoledronate (Zol) could efficiently enhance expansion of tumor antigen specific CD8+ T cells by activation of gamma-delta T cells. In the present study, we studied the immunological response induced by PepTivator® WT1-pulsed Zol-DC vaccines in solid tumors, and also investigated the feasibility and safety of PepTivator® WT1-pulsed Zol-DC vaccines. Five patients with WT1-positive solid tumor (ovary: 4, lung: 1) were enrolled. PBMCs were collected by leukapheresis from the patients and the adherent cell fraction was differentiated into DCs by conventional method. In this vaccine therapy, PepTivator® WT1-pulsed Zol-DC (more than 5x106 cells per injection) was administered to patients subcutaneously for six times every two weeks. In order to examine the specific immune responses to WT1 antigen, PBMCs before therapy (pre-PBMC) and PBMCs after therapy (post-PBMC) were in vitro restimulated with PepTivator® WT1-pulsed Zol-DCs for 14 days and the expanded cells were separated into CD8+ cells and CD4+ cells by MACS, and the antigen specific IFN-gamma- producing cells were detected by ELISpot assay. As a result, no serious adverse events were seen in three patients who had completed all DC vaccines (Patient ID: #1, #2 and #5). DTH reaction was observed in all three patients. During in vitro restimulation and expansion, there was more than three-fold higher expansion of T cells responding to PepTivator® WT1-pulsed Zol-DC in post-PBMC compared to pre-PBMC among two of three patients (#1, #2). In these two patients, the antigen specific IFN-gamma-producing cells were detected in CD8+ T cells from post-PBMC, but not from pre-PBMC. As for CD4+ T cells, however, the antigen specific IFN-gamma-producing cells were not detected, neither in pre-PBMC, nor in post-PBMC. We found that PepTivator® WT1-pulsed Zol-DC vaccines are feasible and safe, and can induce antigen specific CD8+ T cells. We need more extensive investigation for the immunological monitoring and clinical outcome. Citation Format: Shoko Saiwaki, Shigenori Goto, Masashi Takahara, Haruka Matsushita, Takashige Kondo, Hermann Bohnenkamp, Ryuji Maekawa, Takashi Kamigaki. Clinical prospective study of PepTivator® WT1-pulsed DC vaccines with assessment of immunological responses in solid tumors. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2539. doi:10.1158/1538-7445.AM2014-2539

Abstract 5516: Therapeutic vaccination with the survivin-derived multi-epitope vaccine EMD640744 in patients with advanced solid tumors

Abstract Background: Survivin is a promising tumor-associated antigen for cancer immunotherapy that fulfills two major criteria for this purpose: (1) tumor cells depend on the actions of survivin (inhibition of apoptosis, unrestricted proliferation and angiogenesis); and (2) the protein has demonstrated immunogenicity in patients with different cancers. Here we report results of a first-in-man Phase I study with EMD640744, a cocktail of survivin-derived partially modified HLA class I-restricted peptides in Montanide® ISA 51 VG. Methods: This multicenter, open-label, parallel group, randomized study compared the immunologic efficacy, safety, tolerability and clinical activity of three dosages of EMD640744 (30, 100, or 300 µg) in patients with different types of metastatic or locally advanced solid tumors who were positive for at least one relevant HLA antigen (A1, A2, A3, A24, B7). Patients received weekly s.c. injections of EMD640744 for 8 weeks followed by injections every 4 weeks until tumor progression. For the assessment of the primary endpoint, PBMC samples were prepared at baseline and after 4, 8, 12, 16, and 17 weeks. Peptide-specific T cell responses were analyzed by IFN-γ ELISpot. As a secondary analysis, peptide/HLA-multimer staining was performed. Frequencies of CD8+ T cells specific for patient-relevant single HLA-restricted peptides and EMD640744 were determined ex vivo and after short-term in vitro presensitization with EMD640744. Native homologues of modified vaccination peptides were also included in the analysis. Results: Of 66 patients screened, 53 were treated, and a majority was eligible for response analysis: 38 patients were analyzed by ELISpot and 42 by multimers, with positive ex vivo responses observed in 7 (18%) and 14 (33%) patients, respectively. Combining ex vivo data with results after in vitro stimulation, T cell responses were detected in 14 (37%) and 31 (74%) patients by ELISpot and multimer analysis, respectively. Multimer staining revealed a de novo induction of T cells against survivin peptides in at least 16 patients (38%) whereas pre-existent responses were seen in only 4 patients (10%). T cell responses were detected in all dose groups with similar frequencies. Five out of 10 HLA-A2+ patients reacting against the modified A2-binding peptide in ELISpot assays showed responses against its native homologue. The best tumor response according to RECIST was stable disease in 28% of patients. The most frequent treatment-related adverse events (AEs) were Grade 1-2 local injection site reactions and 2 patients experienced treatment-related Grade 3 AEs (granuloma at injection site and thrombosis). Conclusion: Vaccination with EMD640744 was safe and well tolerated and elicited de novo T cell responses against survivin peptides, demonstrating immunological efficacy of EMD640744 in cancer patients. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 5516. doi:10.1158/1538-7445.AM2011-5516

The Tat-conjugated N-terminal region of mucin antigen 1 (MUC1) induces protective immunity against MUC1-expressing tumours

Mucin antigen 1 (MUC1) is overexpressed on various human adenocarcinomas and haematological malignancies and has long been used as a target antigen for cancer immunotherapy. Most of the preclinical and clinical studies using MUC1 have used the tandem repeat region of MUC1, which could be presented by only a limited set of major histocompatibility complex haplotypes. Here, we evaluated N-terminal region (2-147 amino acids) of MUC1 (MUC1-N) for dendritic cell (DC)-based cancer immunotherapy. We used Esherichia coli-derived MUC1-N that was fused to the protein transduction domain of human immunodeficiency virus Tat protein for three reasons. First, mature DCs do not phagocytose soluble protein antigens. Secondly, tumour cells express underglycosylated MUC1, which can generate epitopes repertoire that differs from normal cells, which express hyperglycosylated MUC1. Finally, aberrantly glycosylated MUC1 has been known to impair DC function. In our study, Tat-MUC1-N-loaded DCs induced type 1 T cell responses as well as cytotoxic T lymphocytes efficiently. Furthermore, they could break tolerance in the transgenic breast tumour mouse model, where MUC1-positive breast cancers grow spontaneously. Compared with DCs pulsed with unconjugated MUC1-N, DCs loaded with Tat-conjugated MUC1-N could delay tumour growth more effectively in the transgenic tumour model as well as in the tumour injection model. These results suggest that the recombinant N-terminal part of MUC1, which may provide a diverse epitope repertoire, could be utilized as an effective tumour antigen for DC-based cancer immunotherapy.

EGF receptor variant III as a target antigen for tumor immunotherapy

The EGF receptor (EGFR) is the first tyrosine kinase receptor ever cloned and remains at the forefront of targeted therapies against cancer. Currently, there are four US FDA-approved drugs and several more in Phase III studies that target the EGFR. These drugs, while resulting in some dramatic remissions, have not resulted in strong nor consistent improvements in survival. EGFR variant III (EGFRvIII) is the most common variant of the EGFR and is present in many different cancer types but not in normal tissue. It results from the fusion of exon 1 to exon 8 of the EGFR gene, which results in a novel glycine at the junction. This mutant receptor is constitutively active in these tumors and can lead directly to cancer phenotypes due to its oncogenic properties. EGFRvIII is an attractive target antigen for cancer immunotherapy because it is not expressed in normal tissue and because cells producing EGFRvIII have an enhanced capacity for dysregulated growth, survival, invasion and angiogenesis. In this review, we will discuss preclinical and clinical data from studies using EGFRvIII as the target antigen for immunotherapy, with a focus on the potential for greatly improved survival for patients diagnosed with glioblastoma multiforme.

Listeria monocytogenes as a vector for tumor-associated antigens for cancer immunotherapy

As a facultative intracellular bacterium, Listeria monocytogenes has adapted to live within the cytosol of the host cell. It is actively taken up by antigen-presenting cells through phagocytosis, and as Listeria survive within these cells, it is an ideal vector for the delivery of antigens to be processed and presented through both the class I and II antigen-processing pathways. Once phagocytosed, Listeria produces virulence factors within the phagolysosome of the host cell, which allows it to break out of this organelle and live in the host cytosol. It is possible that these virulence factors can enhance the immunogenicity of tumor-associated antigens, which are poorly immunogenic. Recent progress in the development of this bacterium as a vaccine vector for tumor-associated antigens is discussed in the context of bacterial vectors in general. In several mouse models, Listeria -based vaccines have been demonstrated to be an effective method of influencing tumor growth and eliciting potent antitumor immune responses. Safety issues and the transition of Listeria into human clinical trials will also be discussed in this review.

Identification of Lung Tumor Antigens for Cancer Immunotherapy: Immunological and Molecular Approaches

(2000). Identification of Lung Tumor Antigens for Cancer Immunotherapy: Immunological and Molecular Approaches. Immunological Investigations: Vol. 29, No. 2, pp. 87-91.