MAGE-A3: an immunogenic target used in clinical practice

Gene and Protein Expression of MAGE and Associated Immune Landscape Elements in Non-Small-Cell Lung Carcinoma and Urothelial Carcinomas

Melanoma-associated antigen-A (MAGE-A) is expressed in multiple cancers with restricted expression in normal tissue. We sought to assess the MAGE-A3/A6 expression profile as well as immune landscape in urothelial (UC) and non-small cell lung carcinoma (NSCLC). We also assessed co-expression of immune-associated markers, including programmed cell death ligand 1 (PD-L1) in tumor and/or immune cells, and assessed the effect of checkpoint inhibitor treatment on these markers in the context of urothelial carcinoma. We used formalin-fixed paraffin-embedded (FFPE) tissue sections from a variety of tumor types were screened by IHC for MAGE-A and PD-L1 expression. Gene expression analyses by RNA sequencing were performed on RNA extracted from serial tissue sections. UC tumor samples from patients treated with checkpoint inhibitors were assessed by IHC and NanoString gene expression analysis for MAGE-A and immune marker expression before and after treatment. Overall, 84 samples (57%) had any detectable MAGE-A expression. Detectable MAGE-A expression was present at similar frequencies in both tumor tissue types, with 41 (50%) NSCLC and 43 (64%) UC. MAGE-A expression was not significantly changed before and after checkpoint inhibitor therapy by both IHC and NanoString mRNA sequencing. Other immune markers were similarly unchanged post immune checkpoint inhibitor therapy. Stable expression of MAGE-A3/A6 pre and post checkpoint inhibitor treatment indicates that archival specimens harvested after checkpoint therapy are applicable to screening potential candidates for MAGE therapies.

Advances in adoptive cellular immunotherapy and therapeutic breakthroughs in multiple myeloma

The basic idea of modulating the immune system to better recognize and fight tumor cells has led to the successful introduction of adoptive cellular immunotherapy (ACT). ACT-based treatment regimens, in which the patient's own immune cells are isolated and subsequently expanded (ex vivo) and reinfused, have also contributed significantly to the development of a personalized treatment strategy. Complementing this, the unprecedented advances in ACTs as chimeric antigen receptor (CAR)-T cell therapies and their derivatives such as CAR-NK, CAR-macrophages, CAR-γδT and CAR-NKT have further maximized the therapeutic outcomes. Herein, we provide a comprehensive overview of the development of ACTs in multiple myeloma (MM) and outline how they have evolved from an experimental form to a mainstay of standard clinical settings. Besides, we provide insights into cytokine-induced killer cell (CIK) therapy, an alternative form of ACT that (as CIK or CAR-CIK) has enormous potential in the clinical spectrum of MM. We also summarize the results of the major preclinical and clinical studies of adoptive cell therapy in MM and address the current challenges (such as cytokine release syndrome (CRS) and neurotoxicity) that limit its complete success in the cancer landscape.

Single-cell sequencing unveils extensive intratumoral heterogeneity of cancer/testis antigen expression in melanoma and lung cancer

Cancer/testis antigens (CTAs) are widely expressed in melanoma and lung cancer, emerging as promising targets for vaccination strategies and T-cell-based therapies in these malignancies. Despite recognizing the essential impact of intratumoral heterogeneity on clinical responses to immunotherapy, our understanding of intratumoral heterogeneity in CTA expression has remained limited. We employed single-cell mRNA sequencing to delineate the CTA expression profiles of cancer cells in clinically derived melanoma and lung cancer samples. Our findings reveal a high degree of intratumoral transcriptional heterogeneity in CTA expression. In melanoma, every cell expressed at least one CTA. However, most individual CTAs, including the widely used therapeutic targets NY-ESO-1 and MAGE, were confined to subpopulations of cells and were uncoordinated in their expression, resulting in mosaics of cancer cells with diverse CTA profiles. Coordinated expression was observed, however, mainly among highly structurally and evolutionarily related CTA genes. Importantly, a minor subset of CTAs, including PRAME and several members of the GAGE and MAGE-A families, were homogenously expressed in melanomas, highlighting their potential as therapeutic targets. Extensive heterogeneity in CTA expression was also observed in lung cancer. However, the frequency of CTA-positive cancer cells was notably lower and homogenously expressed CTAs were only identified in one of five tumors in this cancer type. Our findings underscore the need for careful CTA target selection in immunotherapy development and clinical testing and offer a rational framework for identifying the most promising candidates.

Comparative responses to demethylating therapy in animal models of osteosarcoma

Background

The demethylating agent decitabine (DAC) effectively inhibits tumor growth and metastasis by targeting ESR1 methylation to restore estrogen receptor alpha (ERα) signaling and promoting cellular differentiation in models of human osteosarcoma (OSA). Whether this pathway can be targeted in canine OSA patients is unknown.

Methods

Canine OSA tumor samples were tested for ERα expression and ESR1 promoter methylation. Human (MG63.3) and canine (MC-KOS) OSA cell lines and murine xenografts were treated with DAC in vitro and in vivo, respectively. Samples were assessed using mRNA sequencing and tissue immunohistochemistry.

Results

ESR1 is methylated in a subset of canine OSA patient samples and the MC-KOS cell line. DAC treatment led to enhanced differentiation as demonstrated by increased ALPL expression, and suppressed tumor growth in vitro and in vivo. Metastatic progression was inhibited, particularly in the MG63.3 model, which expresses higher levels of DNA methyltransferases DNMT1 and 3B. DAC treatment induced significant alterations in immune response and cell cycle pathways.

Conclusion

DAC treatment activates ERα signaling, promotes bone differentiation, and inhibits tumor growth and metastasis in human and canine OSA. Additional DAC-altered pathways and species- or individual-specific differences in DNMT expression may also play a role in DAC treatment of OSA.

A structure-guided approach to predict MHC-I restriction of T cell receptors for public antigens

Peptides presented by class I major histocompatibility complex (MHC-I) proteins provide biomarkers for therapeutic targeting using T cell receptors (TCRs), TCR-mimicking antibodies (TMAs), or other engineered protein binders. Despite the extreme sequence diversity of the Human Leucocyte Antigen (HLA, the human MHC), a given TCR or TMA is restricted to recognize epitopic peptides in the context of a limited set of different HLA allotypes. Here, guided by our analysis of 96 TCR:pHLA complex structures in the Protein Data Bank (PDB), we identify TCR contact residues and classify 148 common HLA allotypes into T-cell cross-reactivity groups (T-CREGs) on the basis of their interaction surface features. Insights from our work have actionable value for resolving MHC-I restriction of TCRs, guiding therapeutic expansion of existing therapies, and informing the selection of peptide targets for forthcoming immunotherapy modalities.

The potential value of cancer-testis antigens in ovarian cancer: Prognostic markers and targets for immunotherapy

BACKGROUND

Tumor immunotherapy has become an important adjuvant therapy after surgery, radiotherapy, and chemotherapy. In recent years, the role of tumor-associated antigen (TAA) in tumor immunotherapy has become increasingly prominent. Cancer-testis antigen (CTA) is a kind of TAA that is highly restricted in a variety of tumors and can induce an immune response.

AIMS

This review article aimed to evaluate the role of CTA on the progression of ovarian cancer, its diagnostic efficacy, and the potential for immunotherapy.

METHODS

We analyzed publications and outlined a comprehensive of overview the regulatory mechanism, immunogenicity, clinical expression significance, tumorigenesis, and application prospects of CTA in ovarian cancer, with a particular focus on recent progress in CTA-based immunotherapy.

RESULTS

The expression of CTA affects the occurrence, development, and prognosis of ovarian cancer and is closely related to tumor immunity.

CONCLUSION

CTA can be used as a biomarker for the diagnosis and prognosis evaluation of ovarian cancer and is an ideal target for antitumor immunotherapy. These findings provide novel insights on CTA in the improvement of diagnosis and treatment for ovarian cancer. The successes, current challenges and future prospects were also discussed to portray its significant potential.

Tumor-Derived Antigenic Peptides as Potential Cancer Vaccines

Peptide antigens derived from tumors have been observed to elicit protective immune responses, categorized as either tumor-associated antigens (TAAs) or tumor-specific antigens (TSAs). Subunit cancer vaccines incorporating these antigens have shown promise in inducing protective immune responses, leading to cancer prevention or eradication. Over recent years, peptide-based cancer vaccines have gained popularity as a treatment modality and are often combined with other forms of cancer therapy. Several clinical trials have explored the safety and efficacy of peptide-based cancer vaccines, with promising outcomes. Advancements in techniques such as whole-exome sequencing, next-generation sequencing, and in silico methods have facilitated the identification of antigens, making it increasingly feasible. Furthermore, the development of novel delivery methods and a deeper understanding of tumor immune evasion mechanisms have heightened the interest in these vaccines among researchers. This article provides an overview of novel insights regarding advancements in the field of peptide-based vaccines as a promising therapeutic avenue for cancer treatment. It summarizes existing computational methods for tumor neoantigen prediction, ongoing clinical trials involving peptide-based cancer vaccines, and recent studies on human vaccination experiments.

Nucleic acid vaccines-based therapy for triple-negative breast cancer: A new paradigm in tumor immunotherapy arena

Nucleic acid vaccines (NAVs) have the potential to be economical, safe, and efficacious. Furthermore, just the chosen antigen in the pathogen is the target of the immune responses brought on by NAVs. Triple-negative breast cancer (TNBC) treatment shows great promise for nucleic acid-based vaccines, such as DNA (as plasmids) and RNA (as messenger RNA [mRNA]). Moreover, cancer vaccines offer a compelling approach that can elicit targeted and long-lasting immune responses against tumor antigens. Bacterial plasmids that encode antigens and immunostimulatory molecules serve as the foundation for DNA vaccines. In the 1990s, plasmid DNA encoding the influenza A nucleoprotein triggered a protective and targeted cytotoxic T lymphocyte (CTL) response, marking the first instance of DNA vaccine-mediated immunity. Similarly, in vitro transcribed mRNA was first successfully used in animals in 1990. At that point, mice were given an injection of the gene encoding the mRNA sequence, and the researchers saw the production of a protein. We begin this review by summarizing our existing knowledge of NAVs. Next, we addressed NAV delivery, emphasizing the need to increase efficacy in TNBC.

Immunotherapy for lung cancer

Immune checkpoint blockers have transformed non-small-cell lung cancer treatment, but they can lead to autoimmune and inflammatory side effects, leading to the concurrent use of immunosuppressive treatments. In this analysis, we delve into the potential of antibodies checkpoint blockade, focusing on CTLA-4 inhibition using ipilimumab, as a groundbreaking cancer immunotherapy. We also concentrate on the role of biomarkers, particularly PD-L1 activity and mutation significance, in predicting the response to programmed cell death protein 1 blockage and the prevalence of side effects associated with immune-related side effects. In describing the patterns of cancer response to immunotherapy, we underline the limitations of response assessment criteria like RECIST and World Health Organization. We also stress the necessity of ongoing studies and clinical trials, standardized guidelines, and additional research to improve response assessment in the era of immunotherapy.

Bioinformatics-based analysis of programmed cell death pathway and key prognostic genes in gastric cancer: Implications for the development of therapeutics

BACKGROUND

Gastric cancer (GC) represents a major global health burden as a result of its high incidence and poor prognosis. The present study examined the role of the programmed cell death (PCD) pathway and identified key genes influencing the prognosis of patients with GC.

METHODS

Bioinformatics analysis, machine learning techniques and survival analysis were systematically integrated to identify core prognostic genes from the The Cancer Genome Atlas Stomach Adenocarcinoma (TCGA-STAD) dataset. A prognostic model was then developed to stratify patients into high-risk and low-risk groups, and further validated in the GSE84437 dataset. The model also demonstrated clinical relevance with tumor staging and histopathology. Immune infiltration analysis and the potential benefits of immunotherapy for each risk group were assessed. Finally, subgroup analysis was performed based on the expression of three key prognostic genes.

RESULTS

Three core prognostic genes (CAV1, MMP9 and MAGEA3) were identified. The prognostic model could effectively differentiate patients into high-risk and low-risk groups, leading to significantly distinct survival outcomes. Increased immune cell infiltration was observed in the high-risk group, and better potential for immunotherapy outcomes was observed in the low-risk group. Pathways related to cancer progression, such as epithelial-mesenchymal transition and tumor necrosis factor-α signaling via nuclear factor-kappa B, were enriched in the high-risk group. By contrast, the low-risk group showed a number of pathways associated with maintenance of cell functionality and immune responses. The two groups differed in gene mutation patterns and drug sensitivities. Subgroup analysis based on the expression of the three key genes revealed two distinct clusters with distinct survival outcomes, tumor immune microenvironment characteristics and pathway enrichment.

CONCLUSIONS

The present study offers novel insights into the significance of PCD pathways and identifies key genes associated with the prognosis of patients with GC. This robust prognostic model, along with the delineation of distinct risk groups and molecular subtypes, provides valuable tools for risk stratification, treatment selection and personalized therapeutic interventions for GC.

Adjuvant DNA vaccine pNMM promotes enhanced specific immunity and anti-tumor effects

DNA vaccines containing only antigenic components have limited efficacy and may fail to induce effective immune responses. Consequently, adjuvant molecules are often added to enhance immunogenicity. In this study, we generated a tumor vaccine using a plasmid encoding NMM (NY-ESO-1/MAGE-A3/MUC1) target antigens and immune-associated molecules. The products of the vaccine were analyzed in 293 T cells by western blotting, flow cytometry, and meso-scale discovery electrochemiluminescence. To assess the immunogenicity obtained, C57BL/6 mice were immunized using the DNA vaccine. The results revealed that following immunization, this DNA vaccine induced cellular immune responses in C57BL/6 mice, as evaluated by the release of IFN-γ, and we also detected increases in the percentages of nonspecific lymphocytes, as well as those of antigen-specific T cells. Furthermore, immunization with the pNMM vaccine was found to significantly inhibit tumor growth and prolonged the survival of mice with B16-NMM⁺-tumors. Our data revealed that pNMM DNA vaccines not only confer enhanced immunity against tumors but also provide a potentially novel approach for vaccine design. Moreover, our findings provide a basis for further studies on vaccine pharmacodynamics and pharmacology, and lay a solid foundation for clinical application.

Recent Advances in Molecular Mechanisms of Cancer Immunotherapy

Cancer is among the current leading causes of death worldwide, despite the novel advances that have been made toward its treatment, it is still considered a major public health concern. Considering both the serious impact of cancer on public health and the significant side effects and complications of conventional therapeutic options, the current strategies towards targeted cancer therapy must be enhanced to avoid undesired toxicity. Cancer immunotherapy has become preferable among researchers in recent years compared to conventional therapeutic options, such as chemotherapy, surgery, and radiotherapy. The understanding of how to control immune checkpoints, develop therapeutic cancer vaccines, genetically modify immune cells as well as enhance the activation of antitumor immune response led to the development of novel cancer treatments. In this review, we address recent advances in cancer immunotherapy molecular mechanisms. Different immunotherapeutic approaches are critically discussed, focusing on the challenges, potential risks, and prospects involving their use.

Precision Medicine and Novel Therapeutic Strategies in Detection and Treatment of Cancer: Highlights from the 58th IACR Annual Conference

Innovation in both detection and treatment of cancer is necessary for the constant improvement in therapeutic strategies, especially in patients with novel or resistant variants of cancer. Cancer mortality rates have declined by almost 30% since 1991, however, depending on the cancer type, acquired resistance can occur to varying degrees. To combat this, researchers are looking towards advancing our understanding of cancer biology, in order to inform early detection, and guide novel therapeutic approaches. Through combination of these approaches, it is believed that a more complete and thorough intervention on cancer can be achieved. Here, we will discuss the advances and approaches in both detection and treatment of cancer, presented at the 58th Irish Association for Cancer Research (IACR) annual conference.

Development of therapeutic vaccines for the treatment of diseases

Vaccines are one of the most effective medical interventions to combat newly emerging and re-emerging diseases. Prophylactic vaccines against rabies, measles, etc., have excellent effectiveness in preventing viral infection and associated diseases. However, the host immune response is unable to inhibit virus replication or eradicate established diseases in most infected people. Therapeutic vaccines, expressing specific endogenous or exogenous antigens, mainly induce or boost cell-mediated immunity via provoking cytotoxic T cells or elicit humoral immunity via activating B cells to produce specific antibodies. The ultimate aim of a therapeutic vaccine is to reshape the host immunity for eradicating a disease and establishing lasting memory. Therefore, therapeutic vaccines have been developed for the treatment of some infectious diseases and chronic noncommunicable diseases. Various technological strategies have been implemented for the development of therapeutic vaccines, including molecular-based vaccines (peptide/protein, DNA and mRNA vaccines), vector-based vaccines (bacterial vector vaccines, viral vector vaccines and yeast-based vaccines) and cell-based vaccines (dendritic cell vaccines and genetically modified cell vaccines) as well as combinatorial approaches. This review mainly summarizes therapeutic vaccine-induced immunity and describes the development and status of multiple types of therapeutic vaccines against infectious diseases, such as those caused by HPV, HBV, HIV, HCV, and SARS-CoV-2, and chronic noncommunicable diseases, including cancer, hypertension, Alzheimer's disease, amyotrophic lateral sclerosis, diabetes, and dyslipidemia, that have been evaluated in recent preclinical and clinical studies.

Advances in the Lung Cancer Immunotherapy Approaches

Despite the progress in the comprehension of LC progression, risk, immunologic control, and treatment choices, it is still the primary cause of cancer-related death. LC cells possess a very low and heterogeneous antigenicity, which allows them to passively evade the anticancer defense of the immune system by educating cytotoxic lymphocytes (CTLs), tumor-infiltrating lymphocytes (TILs), regulatory T cells (Treg), immune checkpoint inhibitors (ICIs), and myeloid-derived suppressor cells (MDSCs). Though ICIs are an important candidate in first-line therapy, consolidation therapy, adjuvant therapy, and other combination therapies involving traditional therapies, the need for new predictive immunotherapy biomarkers remains. Furthermore, ICI-induced resistance after an initial response makes it vital to seek and exploit new targets to benefit greatly from immunotherapy. As ICIs, tumor mutation burden (TMB), and microsatellite instability (MSI) are not ideal LC predictive markers, a multi-parameter analysis of the immune system considering tumor, stroma, and beyond can be the future-oriented predictive marker. The optimal patient selection with a proper adjuvant agent in immunotherapy approaches needs to be still revised. Here, we summarize advances in LC immunotherapy approaches with their clinical and preclinical trials considering cancer models and vaccines and the potential of employing immunology to predict immunotherapy effectiveness in cancer patients and address the viewpoints on future directions. We conclude that the field of lung cancer therapeutics can benefit from the use of combination strategies but with comprehension of their limitations and improvements.

Nucleic acid vaccination strategies for ovarian cancer

High grade serous carcinoma (HGSC) is one of the most lethal ovarian cancers that is characterised by asymptomatic tumour growth, insufficient knowledge of malignant cell origin and sub-optimal detection. HGSC has been recently shown to originate in the fallopian tube and not in the ovaries. Conventional treatments such as chemotherapy and surgery depend upon the stage of the disease and have resulted in higher rates of relapse. Hence, there is a need for alternative treatments. Differential antigen expression levels have been utilised for early detection of the cancer and could be employed in vaccination strategies using nucleic acids. In this review the different vaccination strategies in Ovarian cancer are discussed and reviewed. Nucleic acid vaccination strategies have been proven to produce a higher CD8+ CTL response alongside CD4+ T-cell response when compared to other vaccination strategies and thus provide a good arena for antitumour immune therapy. DNA and mRNA need to be delivered into the intracellular matrix. To overcome ineffective naked delivery of the nucleic acid cargo, a suitable delivery system is required. This review also considers the suitability of cell penetrating peptides as a tool for nucleic acid vaccine delivery in ovarian cancer.

Cancer-testis antigen lactate dehydrogenase C4 as a novel biomarker of male infertility and cancer

A unique lactate dehydrogenase (LDH) isoenzyme designated as lactate dehydrogenase C4 (LDH-C4) is found in mammalian mature testis and spermatozoa. Thus far, LDH-C4 has been well studied with regard to its gene and amino acid sequences, structure, biological properties, and peptide synthesis. Accumulating evidence has shown that LDH-C4 is closely related to spermatic energy metabolism and plays a critical role in sperm motility, capacitation, and fertilization. Defects in the catalytic activity of LDH-C4 are key to pathophysiological abnormalities underlying infertility. LDH-C4 was originally thought to be present only in mature testis and spermatozoa; however, recent studies have implicated LDH-C4 as a cancer-testis antigen (CTA), owing to its aberrant transcription in a broad spectrum of human neoplasms. This review highlights the recent findings on LDH-C4 with particular emphasis on its role in male infertility and tumors.

Strategies in DNA vaccine for melanoma cancer

According to reports of the international agency for cancer on research, although malignant melanoma shows less prevalence than nonmelanoma skin cancers, it is the major cause of skin cancer mortality. Given that, the production of effective vaccines to control melanoma is eminently required. In this regard, DNA-based vaccines have been extensively investigated for melanoma therapy. DNA vaccines are capable of inducing both cellular and humoral branches of immune responses. These vaccines possess some valuable advantages such as lack of severe side effects and high stability compared to conventional vaccination methods. The ongoing studies are focused on novel strategies in the development of DNA vaccines encoding artificial polyepitope immunogens based on the multiple melanoma antigens, the inclusion of molecular adjuvants to increase the level of immune responses, and the improvement of delivery approaches. In this review, we have outlined the recent advances in the field of melanoma DNA vaccines and described their implications in clinical trials as a strong strategy in the prevention and control of melanoma.

Transcriptomic characterization of cancer-testis antigens identifies MAGEA3 as a driver of tumor progression in hepatocellular carcinoma

Cancer testis antigens (CTAs) are an extensive gene family with a unique expression pattern restricted to germ cells, but aberrantly reactivated in cancer tissues. Studies indicate that the expression (or re-expression) of CTAs within the MAGE-A family is common in hepatocellular carcinoma (HCC). However, no systematic characterization has yet been reported. The aim of this study is to perform a comprehensive profile of CTA de-regulation in HCC and experimentally evaluate the role of MAGEA3 as a driver of HCC progression. The transcriptomic analysis of 44 multi-regionally sampled HCCs from 12 patients identified high intra-tumor heterogeneity of CTAs. In addition, a subset of CTAs was significantly overexpressed in histologically poorly differentiated regions. Further analysis of CTAs in larger patient cohorts revealed high CTA expression related to worse overall survival and several other markers of poor prognosis. Functional analysis of MAGEA3 was performed in human HCC cell lines by gene silencing and in a genetic mouse model by overexpression of MAGEA3 in the liver. Knockdown of MAGEA3 decreased cell proliferation, colony formation and increased apoptosis. MAGEA3 overexpression was associated with more aggressive tumors in vivo. In conclusion MAGEA3 enhances tumor progression and should be considered as a novel therapeutic target in HCC.

Immunohistochemical expression and prognostic significance of MAGE-A in canine oral malignant melanoma

Canine oral malignant melanoma (COMM) is considered a chemo-resistant cancer with a poor long-term prognosis. The melanoma-associated antigen A (MAGE-A) genes, which belong to the cancer-testis antigen family, are expressed in several different canine cancers but not in normal somatic tissue. This study evaluates the expression of MAGE-A proteins and their prognostic role in COMM. The study was conducted in 2 parts. During the first part, biopsies from oral malignant melanomas from 43 dogs were examined and immunohistochemically assessed for expression of MAGE-A proteins. For the second part, the association between MAGE-A expression and outcome was assessed using follow-up data which was available for 20 dogs whose primary tumour had been controlled with surgery +/- radiation therapy. MAGE-A proteins were expressed in 88.4% (38/43) of oral malignant melanomas and had a predominantly cytoplasmic expression pattern. Immunopositivity was observed in more than 50% of the cells in 21 dogs (48.8%). Immunostaining intensity was classified as weak, moderate and intense in 16 (37%), 16 (37%) and 6 (14%) cases, respectively. No staining for MAGE-A was seen in 5 dogs (11%). Dogs whose COMM had weak MAGE-A staining intensity had a median survival time (MST) of 320 days while this was 129 days for dogs with moderate and intense immunostaining (p = 0.161). Dogs whose COMM had >50% of positive staining neoplastic cells had an MST of 141 days and dogs with a staining <50% had an MST of 320 days (p = 0.164). MAGE-A expression did not influence survival in our cohort.

Nuclear overexpression levels of MAGE-A3 predict poor prognosis in patients with prostate cancer

Melanoma antigen gene A3 (MAGE-A3) is one of the most immunogenic cancer testis antigens and is common in various types of cancers. In this study, for the first time, we performed immunohistochemical analysis to evaluate the expression of MAGE-A3 in 153 prostate tissue samples including prostate cancer (PCa), benign prostatic hyperplasia (BPH), and high-grade prostatic intraepithelial neoplasia (HPIN). Increased both nuclear and cytoplasmic expression of MAGE-A3 was significantly found in PCa tissues compared with both HPIN and BPH tissues (nuclear expression at p = 0.011, and cytoplasmic expression at p = 0.034; for both comparisons p < 0.0001, respectively). A significant correlation was observed between higher nuclear and cytoplasmic expressions of MAGE-A3 with Gleason score (p < 0.0001 and 0.006, respectively). Increased expression of MAGE-A3 was associated with shorter biochemical recurrence-free survival (BCR-FS) and disease-free survival (DFS) of patients (p = 0.042 and = 0.0001, respectively). In multivariate analysis, nuclear expression of MAGE-A3 and Gleason score (≤7 vs >7) was independent predictors of the DFS (both; p = 0.019). Nuclear expression of MAGE-A3 was also significantly related to BCR-FS (p = 0.015). MAGE-A3 can be considered as a predictor for poor prognosis and an option for vaccine immunotherapy in patients with PCa.

Cancer Vaccines: Antigen Selection Strategy

Unlike traditional cancer therapies, cancer vaccines (CVs) harness a high specificity of the host’s immunity to kill tumor cells. CVs can train and bolster the patient’s immune system to recognize and eliminate malignant cells by enhancing immune cells’ identification of antigens expressed on cancer cells. Various features of antigens like immunogenicity and avidity influence the efficacy of CVs. Therefore, the choice and application of antigens play a critical role in establishing and developing CVs. Tumor-associated antigens (TAAs), a group of proteins expressed at elevated levels in tumor cells but lower levels in healthy normal cells, have been well-studied and developed in CVs. However, immunological tolerance, HLA restriction, and adverse events are major obstacles that threaten TAA-based CVs’ efficacy due to the “self-protein” characteristic of TAAs. As “abnormal proteins” that are completely absent from normal cells, tumor-specific antigens (TSAs) can trigger a robust immune response against tumor cells with high specificity and without going through central tolerance, contributing to cancer vaccine development feasibility. In this review, we focus on the unique features of TAAs and TSAs and their application in vaccines, summarizing their performance in preclinical and clinical trials.

Immunological and functional aspects of MAGEA3 cancer/testis antigen

Identification of ectopic gene activation in cancer cells serves as a basis for both gene signature-guided tumor targeting and unearthing of oncogenic mechanisms to expand the understanding of tumor biology/oncogenic process. Proteins expressed only in germ cells of testis and/or placenta (immunoprivileged organs) and in malignancies are called cancer testis antigens; they are antigenic because of the lack of antigen presentation by those specific cell types (germ cells), which limits the exposure of the proteins to the immune cells. Since the Cancer Testis Antigens (CTAs) are immunogenic and expressed in a wide variety of cancer types, CT antigens have become interesting target for immunotherapy against cancer. Among CT antigens MAGEA family is reported to have 12 members (MAGEA1 to MAGEA12). The current review highlights the studies on MAGEA3 which is a CT antigen and reported in almost all types of cancer. MAGEA3 is well tried for cancer immunotherapy. Recent advances on its functional and immunological aspect warranted much deliberation on effective therapeutic approach, thus making it a more interesting target for cancer therapy.

Cancer-testis antigens: An update on their roles in cancer immunotherapy

BACKGROUND

Several recent studies have assessed suitability of tumor antigens for immunotherapy. Based on the restricted expression pattern in somatic tissues, cancer-testis antigens (CTAs) are possible candidates for cancer immunotherapy. These antigens are expressed in various tumors including gastrointestinal, breast, skin and hematologic malignancies.

OBJECTIVES

To find clinical trials utilizing CTAs in cancer patients.

METHODS

We searched PubMed, google scholar and specific websites that registers clinical trials.

RESULTS

A number of clinical trials have been designed to evaluate safety and efficacy of CTA-based treatments. The results of some of them have been promising. In the current literature search, we summarized the clinical trials of CTA-based therapies in cancer patients.

CONCLUSIONS

Based on the availability of different formulations of CTA-based vaccines, future researches should compare efficiency of these modalities.

LINC01234/MicroRNA-31-5p/MAGEA3 Axis Mediates the Proliferation and Chemoresistance of Hepatocellular Carcinoma Cells

Hepatocellular carcinoma (HCC) is a prevalent malignancy characterized by aggressiveness and poor prognosis; however, the molecular mechanism remains to be fully identified. Based on the analysis of The Cancer Genome Atlas (TCGA) database, melanoma-associated antigen A3 (MAGEA3) and long non-coding RNA (lncRNA) LINC01234 were upregulated in HCC and associated with poor prognosis of HCC. We investigated the mechanism of how MAGEA3 and LINC01234 influenced HCC cellular functions and cisplatin resistance. MAGEA3 depletion inhibited proliferation, invasion, and cisplatin resistance of HepG2 cells and Huh7 cells in vitro, reduced resistance-associated protein 2 (MRP2), MRP3, and multidrug resistance protein 1 (MDR-1) expression, and elevated ALB expression. RNA pull-down and RIP assays identified the binding of LINC01234 and MAGEA3 to microRNA-31-5p (miR-31-5p). LINC01234 could restore MAGEA3 expression by binding to miR-31-5p. Furthermore, we delivered plasmids into HepG2 cells and Huh7 cells to alter the expression of LINC01234 and miR-31-5p. When miR-31-5p was downregulated, the proliferation and invasion of HepG2 cells and Huh7 cells were enhanced and the cisplatin-induced apoptosis was inhibited, while LINC01234 knockdown could diminish the effects caused by miR-31-5p depletion. In summary, these data highlight the vital role of MAGEA3/LINC01234/miR-31-5p axis in the HCC progression and chemoresistance of HCC cells.

Curatopes Melanoma: A Database of Predicted T-cell Epitopes from Overly Expressed Proteins in Metastatic Cutaneous Melanoma

Therapeutic anticancer vaccination has been adapted as an immunotherapy in several solid tumors. However, the selection of promising candidates from the total quantity of possible epitopes poses a challenge to clinicians and bioinformaticians alike, and very few epitopes have been tested in experimental or clinical settings to validate their efficacy. Here, we present a comprehensive database of predicted nonmutated peptide epitopes derived from genes that are overly expressed in a group of 32 melanoma biopsies compared with healthy tissues and that were filtered against expression in a curated list of survival-critical tissues. We hypothesize that these "self-tolerant" epitopes have two desirable properties: they do not depend on mutations, being immediately applicable to a large patient collective, and they potentially cause fewer autoimmune reactions. To support epitope selection, we provide an aggregated score of expected therapeutic efficiency as a shortlist mechanism. The database has applications in facilitating epitope selection and trial design and is freely accessible at https://www.curatopes.com. SIGNIFICANCE: A database is presented that predicts and scores antitumor T-cell epitopes, with a focus on tolerability and avoidance of severe autoimmunity, offering a supplementary epitope set for further investigation in immunotherapy.

Cellular immune responses against cancer-germline genes in cancers

BACKGROUND

Cancer-germline genes are a class of genes that are normally expressed in testis, trophoblast and few somatic tissues but abnormally expressed in tumor tissues. Their expression signature indicates that they can induce cellular immune responses, thus being applied as targets in cancer immunotherapy.

OBJECTIVES

To obtain the data of cellular immune responses against cancer-germline genes in cancer.

METHODS

We searched PubMed/Medline with the key words cancer-germline antigen, cancer-testis antigen, CD4+ T cell, CD8+ T cell and cancer.

RESULTS

About 40 cancer-germline genes have been shown to induce T cell specific responses in cancer patients. Melanoma, lung and breast cancer are among the mostly assessed cancer types. Several epitopes have been identified which can be used in immunotherapy of cancer.

CONCLUSION

Cellular immune responses against cancer-germline genes are indicative of appropriateness of these genes as therapeutic targets.

Cancer-Testis Antigen Peptide Vaccine for Cancer Immunotherapy: Progress and Prospects

Cancer vaccines, including peptide-based vaccines, have been considered a key tool of effective and protective cancer immunotherapy because of their capacity to provide long-term clinical benefit for tumors. Among a large number of explorations of peptide antigen-based vaccines, cancer-testis antigens (CTAs), which are activated in cancers but silenced in normal tissues (except testis tissue), are considered as ideal targets. Currently, personalized treatment for cancer has become a trend due to its superior clinical efficacy. Thus, we envisage rational selection of CTA peptides to design "personalized" CTA peptide vaccines. This review summarizes the advances in CTA peptide vaccine research and discusses the feasibility of establishing "personalized" CTA peptide vaccines.

Application of cancer-testis antigens in immunotherapy of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a worldwide common malignancy with poor prognosis. Several studies have aimed at identification of appropriate biomarkers for early detection of this cancer. Cancer-testis antigens (CTAs) as a novel group of tumor-associated antigens have been demonstrated to be expressed in HCC samples as well as peripheral blood samples from these patients but not in the corresponding adjacent noncancerous samples. Such pattern of expression has provided them an opportunity to be used as immunotherapeutic targets. The detection of spontaneous immune responses against CTAs in HCC patients has prompted design of CTA-based immunotherapeutic protocols in these patients. The results of some clinical trials have been promising in a subset of patients.

Cancer-testis antigens in ovarian cancer: implication for biomarkers and therapeutic targets

Ovarian cancer remains the most fatal gynecologic malignancy worldwide due to delayed diagnosis as well as recurrence and drug resistance. Thus, the development of new tumor-related molecules with high sensitivity and specificity to replace or supplement existing tools is urgently needed. Cancer-testis antigens (CTAs) are exclusively expressed in normal testis tissues but abundantly found in several types of cancers, including ovarian cancer. Numerous novel CTAs have been identified by high-throughput sequencing techniques, and some aberrantly expressed CTAs are associated with ovarian cancer initiation, clinical outcomes and chemotherapy resistance. More importantly, CTAs are immunogenic and may be novel targets for antigen-specific immunotherapy in ovarian cancer. In this review, we attempt to characterize the expression of candidate CTAs in ovarian cancer and their clinical significance as biomarkers, activation mechanisms, function in malignant phenotypes and applications in immunotherapy.

Humoral immune responses against cancer-testis antigens in human malignancies

BACKGROUND

Cancer-testis antigens (CTAs) are a class of cancer antigens with extensive expression in human cancers. Many researchers have detected antibody responses against these tumor antigens in serum of cancer patients.

OBJECTIVES

To evaluate the relevance of humoral immune responses against CTAs in clinical outcome of cancer patientsMETHODS: We searched PubMed/Medline with the key words cancer-testis antigen, antibody, humoral response and cancer.

RESULTS

Humoral immune responses against CTAs have been detected in several human malignancies including skin, breast, brain and ovarian cancers. Some studies have shown associations between the presence of these responses in patients and patients' survival.

CONCLUSION

Humoral immune responses against CTAs are putative biomarkers for cancer detection and follow-up.

Urine exosome gene expression of cancer-testis antigens for prediction of bladder carcinoma

Background

Exosomes have been regarded as emerging tools for cancer diagnosis. Tumor-derived exosomes contain molecules that enhance cancer progression and affect immune responses.

Material and methods

In the present study, we evaluated expression of seven cancer-testis antigens (CTAs) that are regarded as putative biomarkers and immunotherapeutic targets along with NMP22 in urinary exosomes of bladder cancer patients, healthy subjects and patients affected with nonmalignant urinary disorders.

Results

Exosomal expression of MAGE-B4 was significantly higher in bladder cancer patients compared with normal samples (expression ratio=2.68, P=0.01). However, its expression was lower in bladder cancer patients compared with benign prostate hyperplasia (BPH) patients (expression ratio=0.17, P=0.01). Exosomal expression of NMP22 was significantly higher in bladder cancer patients compared with BPH patients (expression ratio=9.22, P=0.02). Expressions of other genes were not significantly different between bladder cancer patients and normal/nonmalignant samples. We found significant correlation between MAGE-A3 and MAGE-B4 expressions in exosomes obtained from controls. In addition, TSGA10 expression was correlated with expression of NMP22 in both cancer patients and controls.

Conclusion

The present study provides evidences for differential expression of CTAs in urinary exosomes of bladder cancer patients and urogenital disorders and warrants further studies for assessment of their significance in cancer diagnosis and immunotherapeutic approaches.

Association of homogeneous inflamed gene signature with a better outcome in patients with metastatic melanoma treated with MAGE-A3 immunotherapeutic

PURPOSE

This study assessed clinical activity, safety and immunogenicity of MAGE-A3 immunotherapeutic in patients with MAGE-A3-positive metastatic melanoma.

PATIENTS AND METHODS

In this open-label, multicentre, uncontrolled, Phase II study (ClinicalTrials.gov NCT00896480), patients received ≤24 doses of MAGE-A3 immunotherapeutic (4-cycle schedule). At screening, two skin lesions were biopsied for MAGE-A3 expression analysis and presence/absence of a previously identified gene signature (GS) associated with favourable clinical outcome. Clinical activity was assessed in terms of clinical response, time-to-treatment failure (TTF) and progression-free survival (PFS). Adverse events (AEs) and serious AEs (SAEs) were recorded. MAGE-A3-specific immune responses were assessed. Clinical activity and immunogenicity were analysed overall and separately in patients with 2/2 (GS+/+), 1/2 (GS+/-) or 0/2 (GS-/-) biopsies presenting GS.

RESULTS

Of 49 screened patients, 32 had MAGE-A3-positive tumours; 24 (8 GS+/+, 8 GS+/-, 8 GS-/-) were treated. Two complete (GS+/+ patients) and two partial responses (one GS+/+, one GS+/-) were reported; of note, one of the two complete responses was unlikely to be related to the study treatment. Median TTF and PFS were 14.8 and 7.2 months for GS+/+, 2.3 and 2.8 months for GS+/- and 2.4 and 2.9 months for GS-/- patients. Three grade 3 AEs and two SAEs unrelated to treatment were reported. All patients were seropositive for MAGE-A3 antibodies on vaccination with no differences between the different GS profiles. MAGE-A3-specific CD4+ and CD8+ T cell immunogenicity was detected; 12/16 (75.0%) of patients presented CD4+ T cell responses.

CONCLUSION

Treatment with MAGE-A3 immunotherapeutic showed signs of clinical activity in GS+/+ patients. Treatment was well tolerated and immunogenic. No differences in immune responses according to GS status were observed.

TRIAL REGISTRATION NUMBER

NCT00896480 (Results).

Melanoma: a prototype of cancer-testis antigen-expressing malignancies

Melanoma is the first malignancy in which expression and immunogenicity of cancer-testis antigens (CTAs) have been documented. Several CTAs have been shown to be expressed in melanoma samples especially those with metastatic potential. Many of them have been shown to exert oncogenic effects through modulation of essential pathways involved in melanoma. The crucial role of CTAs in the pathogenesis of melanoma, the high prevalence of expression of CTA panels in melanoma and the presence of spontaneous as well as inducible immune responses against CTAs in melanoma patients potentiate CTAs as immunotherapeutic targets. Numerous clinical trials are now ongoing to evaluate CTA-based immunotherapeutic effects in melanoma patient's survival. NY-ESO-1 and MAGE antigens have the most promising results up to now.

Expression analysis of cancer-testis genes in prostate cancer reveals candidates for immunotherapy

Prostate cancer is a prevalent disorder among men with a heterogeneous etiological background. Several molecular events and signaling perturbations have been found in this disorder. Among genes whose expressions have been altered during the prostate cancer development are cancer-testis antigens (CTAs). This group of antigens has limited expression in the normal adult tissues but aberrant expression in cancers. This property provides them the possibility to be used as cancer biomarkers and immunotherapeutic targets. Several CTAs have been shown to be immunogenic in prostate cancer patients and some of the have entered clinical trials. Based on the preliminary data obtained from these trials, it is expected that CTA-based therapeutic options are beneficial for at least a subset of prostate cancer patients.

Cancer/testis Antigen MAGEA3 Interacts with STAT1 and Remodels the Tumor Microenvironment

Cancer-testis antigen MAGEA3, being restrictedly expressed in testis and various kinds of tumors, has long been considered as an ideal target for immunotherapy. In this study, we report that MAGEA3 interacts with STAT1 and regulates the expression of tyrosine phosphorylated STAT1 (pY-STAT1) in tumor cells. We show that pY-STAT1 is significantly up-regulated when MAGEA3 is silenced by MAGEA3-specific siRNA. RNA sequencing analysis identified 274 STAT1-related genes to be significantly altered in expression level in MAGEA3 knockdown cells. Further analysis of these differentially expressed genes with GO enrichment and KEGG pathway revealed that they are mainly enriched in plasma membrane, extracellular region and MHC class I protein complex, and involved in the interferon signaling pathways, immune response, antigen presentation and cell chemotaxis. The differentially expressed genes associated with chemokines, antigen presentation and vasculogenic mimicry formation were validated by biological experiments. Matrigel matrix-based tube formation assay showed that silencing MAGEA3 in tumor cells impairs tumor vasculogenic mimicry formation. These data indicate that MAGEA3 expression in tumor cells is associated with immune cells infiltration into tumor microenvironment and anti-tumor immune responses, implying that it may play an important role in tumor immune escape. Our findings reveal the potential impact of MAGEA3 on the immunosuppressive tumor microenvironment and will provide promising strategies for improving the efficacy of MAGEA3-targeted immunotherapy.

Long Non Coding RNA Expression Intersecting Cancer and Spermatogenesis: A Systematic Review

Background: Numerous similarities have been noted between gametogenic and tumorigenic programs in features such as global hypomethylation, immune evasion, immortalization, meiosis induction, and migration. In addition, aberrant expression of testis specific genes has been detected in various cancers which has led to categorization of these genes as “cancer-testis genes”. Most of the examples identified in this category are protein encoding. However, recent studies have revealed that non-coding RNAs, including long non coding RNAs (lncRNAs), may have essential regulatory roles in telomere biology, chromatin dynamics, modulation of gene expression and genome structural organization. All of these functions are implicated in both gametogenic and tumorigenic programs. Methods: In the present study, we conducted a computerized search of the MEDLINE/PUBMED and Embase databases with the key words lncRNA, gametogenesis, testis and cancer. Results: We found a number of lncRNAs with essential roles and notable expression in both gametogenic and cancer tissues. Conclusions: Comparison between cancer tissues and gametogenic tissues has shown that numerous lncRNAs are expressed in both, playing similar roles in processes modulated by signaling pathways such as Wnt/β-catenin and PI3K/AKT/mTOR. Evaluation of expression patterns and functions of these genes should pave the way to discovery of biomarkers for early detection, prognostic assessment and evaluation of therapeutic responses in cancers.

Roles of cancer/testis antigens (CTAs) in breast cancer

Breast cancer is the most common cancer diagnosed and is the second leading cause of cancer death among women in the US. For breast cancer, early diagnosis and efficient therapy remains a significant clinical challenge. Therefore, it is necessary to identify novel tumor associated molecules to target for biomarker development and immunotherapy. In this regard, cancer testis antigens (CTAs) have emerged as a potential clinical biomarker targeting immunotherapy for various malignancies due to the nature of its characteristics. CTAs are a group of tumor associated antigens (TAAs) that display normal expression in immune-privileged organs, but display aberrant expression in several types of cancers, particularly in advanced cancers. Investigation of CTAs for the clinical management of breast malignancies indicates that these TAAs have potential roles as novel biomarkers, with increased specificity and sensitivity compared to those currently used in the clinic. Moreover, TAAs could be therapeutic targets for cancer immunotherapy. This review is an attempt to address the promising CTAs in breast cancer and their possible clinical implications as biomarkers and immunotherapeutic targets with particular focus on challenges and future interventions.

CD40 Signaling Drives Potent Cellular Immune Responses in Heterologous Cancer Vaccinations

Antagonistic antibodies targeting coinhibitory receptors have revolutionized the treatment of cancer by inducing durable immune responses and clinical remissions in patients. In contrast, success of agonistic costimulatory antibodies has thus far been limited because of the insufficient induction of adaptive immune responses. Here, we describe a novel vaccination method consisting of a primary dendritic cell (DC) immunization followed by a composite vaccination, including an agonistic CD40 antibody, soluble antigen, and a TLR3 agonist, referred to as CoAT. In mice, DC/CoAT prime-boost vaccinations targeting either MHC class I or II neoantigens or tumor-associated antigens rendered up to 60% of the total T-cell population specific for a single tumor epitope. DC/CoAT induced durable and complete remissions of large subcutaneous tumors without detectable side effects. Thus, booster vaccinations with agonistic costimulatory antibodies represent an ideal means to amplify DC vaccinations and induce robust T-cell immune responses while providing maximum flexibility regarding the choice of antigen. Cancer Res; 77(8); 1918-26. ©2017 AACR.

GTL001 and bivalent CyaA-based therapeutic vaccine strategies against human papillomavirus and other tumor-associated antigens induce effector and memory T-cell responses that inhibit tumor growth

GTL001 is a bivalent therapeutic vaccine containing human papillomavirus (HPV) 16 and HPV18 E7 proteins inserted in the Bordetella pertussis adenylate cyclase (CyaA) vector intended to prevent cervical cancer in HPV-infected women with normal cervical cytology or mild abnormalities. To be effective, therapeutic cervical cancer vaccines should induce both a T cell-mediated effector response against HPV-infected cells and a robust CD8⁺ T-cell memory response to prevent potential later infection. We examined the ability of GTL001 and related bivalent CyaA-based vaccines to induce, in parallel, effector and memory CD8⁺ T-cell responses to both vaccine antigens. Intradermal vaccination of C57BL/6 mice with GTL001 adjuvanted with a TLR3 agonist (polyinosinic-polycytidylic acid) or a TLR7 agonist (topical 5% imiquimod cream) induced strong HPV16 E7-specific T-cell responses capable of eradicating HPV16 E7-expressing tumors. Tumor-free mice also had antigen-specific memory T-cell responses that protected them against a subsequent challenge with HPV18 E7-expressing tumor cells. In addition, vaccination with bivalent vaccines containing CyaA-HPV16 E7 and CyaA fused to a tumor-associated antigen (melanoma-specific antigen A3, MAGEA3) or to a non-viral, non-tumor antigen (ovalbumin) eradicated HPV16 E7-expressing tumors and protected against a later challenge with MAGEA3- and ovalbumin-expressing tumor cells, respectively. These results show that CyaA-based bivalent vaccines such as GTL001 can induce both therapeutic and prophylactic anti-tumor T-cell responses. The CyaA platform can be adapted to different antigens and adjuvants, and therefore may be useful for developing other therapeutic vaccines.

[Research Progress of Exosomes in Lung Cancer Diagnosis and Treatment]

As the leading cause of morbidity and cancer related-death worldwide, lung cancer has a serious threat to human health. Exosomes are nanoscale lipid membrane vesicles derived from multivesicles, which containing active biomolecules including proteins, lipids, nucleic acids and etc. Exosomes play important roles in lung cancer initiation and progression by promoting the formation of tumor microenvironment, enhancing tumor invasive and metastasis capability, leading to immunosuppression and resistance to chemoradiotherapy, and also have the application value in early diagnosis and treatment. This review summarizes the research progress of exosomes in tumor initiation and progression, and its roles in diagnosis and treatment of lung cancer.

In Vitro Assessment of the Expression and T Cell Immunogenicity of the Tumor-Associated Antigens BORIS, MUC1, hTERT, MAGE-A3 and Sp17 in Uterine Cancer

Background: While immunotherapy moved to the forefront of treatment of various cancers, it remains underexplored for uterine cancer. This might be due to the small patient population with advanced endometrial carcinoma and uterine sarcoma. Data about immunotherapeutic targets are scarce in endometrial carcinoma and lacking in uterine sarcoma. Methods: Expression of five tumor-associated antigens (TAA) (BORIS, MUC1, hTERT, MAGE-A3 and Sp17) was validated in uterine tumor samples by immunohistochemistry (IHC) and/or quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR). TAA immunogenicity was analyzed by determining spontaneous T cell responses towards overlapping peptide pools covering the whole TAA in patient blood. Results: At mRNA level, MAGE-A3 and Sp17 were overexpressed in a minority of patients and BORIS was moderately overexpressed (26% in endometrial carcinoma and 62% in uterine sarcoma). hTERT was overexpressed in the vast majority of tumors. On protein level, MUC1 was upregulated in primary, recurrent and metastatic EMCAR and in metastatic US tumors. hTERT protein was highly expressed in both normal and malignant tissue. Spontaneous TAA-specific T cell responses were detected in a minority of patients, except for hTERT to which T cell responses occurred more frequently. Conclusions: These data point to MUC1 and hTERT as most suitable targets based on expression levels and T cell immunogenicity for use in immunotherapeutic regimens.