Expression of cancer-testis antigen (CTA) genes in intrahepatic cholangiocarcinoma

Gene of the month: cancer testis antigen gene 1b (NY-ESO-1)

Cancer testis antigen gene 1B (CTAG1B) and its associated gene product; New York oesophageal squamous carcinoma 1 (NY-ESO-1), represent a unique and promising target for cancer immunotherapy. As a member of the cancer testis antigen family (CTA), the protein's restricted expression pattern and ability to elicit spontaneous humoural and cellular immune responses has resulted in a plethora of novel modalities and approaches attempting to harness its immunotherapeutic anti-cancer potential. Here, we discuss the structure and function of CTAG1B/NY-ESO-1 in both health and disease, immunohistochemical detection, as well as the most promising advances in the development of associated anti-cancer therapies. From cancer vaccines to engineered cellular therapy approaches, a multitude of immunotherapies targeting CTA's are coming to the forefront of oncology. Although the efficacy of such approaches have yet to provide convincing evidence of durable response, early phase clinical trial data has resulted in some exciting findings which will have significant potential to act as a platform for future practice changing technologies.

Immunogenomics of cholangiocarcinoma

The development of cholangiocarcinoma spans years, if not decades, during which the immune system becomes corrupted and permissive to primary tumor development and metastasis. This involves subversion of local immunity at tumor sites, as well as systemic immunity and the wider host response. While immune dysfunction is a hallmark of all cholangiocarcinoma, the specific steps of the cancer-immunity cycle that are perturbed differ between patients. Heterogeneous immune functionality impacts the evolutionary development, pathobiological behavior, and therapeutic response of these tumors. Integrative genomic analyses of thousands of primary tumors have supported a biological rationale for immune-based stratification of patients, encompassing immune cell composition and functionality. However, discerning immune alterations responsible for promoting tumor initiation, maintenance, and progression from those present as bystander events remains challenging. Functionally uncoupling the tumor-promoting or tumor-suppressing roles of immune profiles will be critical for identifying new immunomodulatory treatment strategies and associated biomarkers for patient stratification. This review will discuss the immunogenomics of cholangiocarcinoma, including the impact of genomic alterations on immune functionality, subversion of the cancer-immunity cycle, as well as clinical implications for existing and novel treatment strategies.

Immunology and immunotherapy of cholangiocarcinoma

Cholangiocarcinoma is the second most common primary liver cancer. Its incidence is low in the Western world but is rising globally. Surgery, chemotherapy and radiation therapy have been the only treatment options for decades. Progress in our molecular understanding of the disease and the identification of druggable targets, such as IDH1 mutations and FGFR2 fusions, has provided new treatment options. Immunotherapy has emerged as a potent strategy for many different types of cancer and has shown efficacy in combination with chemotherapy for cholangiocarcinoma. In this Review, we discuss findings related to key immunological aspects of cholangiocarcinoma, including the heterogeneous landscape of immune cells within the tumour microenvironment, the immunomodulatory effect of the microbiota and IDH1 mutations, and the association of immune-related signatures and patient outcomes. We introduce findings from preclinical immunotherapy studies, discuss future immune-mediated treatment options, and provide a summary of results from clinical trials testing immune-based approaches in patients with cholangiocarcinoma. This Review provides a thorough survey of our knowledge on immune signatures and immunotherapy in cholangiocarcinoma.

Immunotherapy: Pancreatic Cancer and Extrahepatic Biliary Tract Cancer

Pancreatic ductal adenocarcinoma (PDAC) and extrahepatic biliary tract cancer (BTC) are among the malignancies with the highest morbidity and mortality. Despite increasing knowledge on biology and novel therapies, outcome remains poor in these patients. Recent progress in immunotherapies created new hopes in the treatment of PDAC and extrahepatic BTC. Several trials tested immunotherapies in various therapeutic situations as monotherapies or in combinations. Although responses were seen in some of the trials, the value of immunotherapy in PDAC and extrahepatic BTC remains unclear in the current situation, especially regarding the complex biological characteristics with a high stroma component, intrinsic resistance mechanisms and an immunosuppressive, hypoxic microenvironment. These major hurdles have to be taken into account and overcome if immunotherapies should be successful in these tumor entities. Thereby, combinational approaches that allow on the one hand targeted therapy and on the other restore or boost the function of immune cells are promising.

Anti-NY-ESO-1 autoantibody may be a tumor marker for intrahepatic cholangiocarcinoma

Anti-NY-ESO-1 antibody is observed in a multitude of malignancies. This study was aimed to evaluate the expression of serum anti-NY-ESO-1 antibodies and its prognostic value in intrahepatic cholangiocarcinoma. A total of 103 patients with intrahepatic cholangiocarcinoma were enrolled in the study. Enzyme-linked immunosorbent assay (ELISA) was performed to detect the serum level of anti-NY-ESO-1 antibody. Western blotting was performed to assess the NY-ESO-1 expression in tumor and adjacent tissues. The serum NY-ESO-1 antibody was detected in 18.4% of patients with intrahepatic cholangiocarcinoma, a value that was significantly higher than that in patients with chronic Hepatitis B. Serum NY-ESO-1 antibody was positively correlated with tumor differentiation, lymphatic metastasis, cTNM stage and abdominal pain. Finally, there was a higher cumulative survival rate in patients with serum NY-ESO-1 positivity than in those with serum NY-ESO-1 negativity among the patients with stage III + IV. Our data uncovered that NY-ESO-1 antibody might be a helpful tumor marker and prognostic predictor in intrahepatic cholangiocarcinoma.

Cancer vaccines and immunotherapeutic approaches in hepatobiliary and pancreatic cancers

Hepatobiliary and pancreatic cancers along with other gastrointestinal malignancies remain the leading cause of cancer-related deaths worldwide. Strategies developed in the recent years on immunotherapy and cancer vaccines in the setting of primary liver cancer as well as in pancreatic cancer are the scope of this review. Significance of orthotopic and autochthonous animal models which mimic and/or closely reflect human malignancies allowing for a prompt and trustworthy analysis of new therapeutics is underlined. Combinational approaches that on one hand, specifically target a defined cancer-driving pathway, and on the other hand, restore the functions of immune cells, which effector functions are often suppressed by a tumor milieu, are shown to have the strongest perspectives and future directions. Among combinational immunotherapeutic approaches a personalized- and individual cancer case-based therapy is of special importance.

New York esophageal squamous cell carcinoma-1 and cancer immunotherapy

New York esophageal squamous cell carcinoma 1 (NY-ESO-1) is a known cancer testis gene with exceptional immunogenicity and prevalent expression in many cancer types. These characteristics have made it an appropriate vaccine candidate with the potential application against various malignancies. This article reviews recent knowledge about the NY-ESO-1 biology, function, immunogenicity and expression in cancers as well as and the results of clinical trials with this antigen.

MAGE-A3: an immunogenic target used in clinical practice

Melanoma antigen family A, 3 (MAGE-A3) is a cancer-testis antigen whose expression has been demonstrated in a wide array of malignancies including melanoma, brain, breast, lung and ovarian cancer. In addition, its ability to elicit spontaneous humoral and cellular immune responses has been shown in cancer patients. As antigen-specific immune responses can be stimulated by immunization with MAGE-A3, several clinical trials have used MAGE-A3 vaccines to observe clinical responses. The frequent expressions of this antigen in various tumors and its immunogenicity in cancer patients have led to application of this antigen in cancer immunotherapy. However, the results of recent clinical trials indicate that there is a need for research in the vaccine design, adjuvant selection as well as patient selection criteria.

Downstream and intermediate interactions of synovial sarcoma-associated fusion oncoproteins and their implication for targeted therapy

Synovial sarcoma (SS), an aggressive type of soft tissue tumor, occurs mostly in adolescents and young adults. The origin and molecular mechanism of the development of SS remain only partially known. Over 90% of SS cases are characterized by the t(X;18)(p11.2;q11.2) translocation, which results mainly in the formation of SS18-SSX1 or SS18-SSX2 fusion genes. In recent years, several reports describing direct and indirect interactions of SS18-SSX1/SSX2 oncoproteins have been published. These reports suggest that the fusion proteins particularly affect the cell growth, cell proliferation, TP53 pathway, and chromatin remodeling mechanisms, contributing to SS oncogenesis. Additional research efforts are required to fully explore the protein-protein interactions of SS18-SSX oncoproteins and the pathways that are regulated by these partnerships for the development of effective targeted therapy.

Cancer/Testis Antigen MAGE-C1/CT7: new target for multiple myeloma therapy

Cancer/Testis Antigens (CTAs) are a promising class of tumor antigens that have a limited expression in somatic tissues (testis, ovary, fetal, and placental cells). Aberrant expression of CTAs in cancer cells may lead to abnormal chromosome segregation and aneuploidy. CTAs are regulated by epigenetic mechanisms (DNA methylation and acetylation of histones) and are attractive targets for immunotherapy in cancer because the gonads are immune privileged organs and anti-CTA immune response can be tumor-specific. Multiple myeloma (MM) is an incurable hematological malignancy, and several CTAs have been detected in many MM cell lines and patients. Among CTAs expressed in MM we must highlight the MAGE-C1/CT7 located on the X chromosome and expressed specificity in the malignant plasma cells. MAGE-C1/CT7 seems to be related to disease progression and functional studies suggests that this CTA might play a role in cell cycle and mainly in survival of malignant plasma cells, protecting myeloma cells against spontaneous as well as drug-induced apoptosis.

Expression and prognostic significance of cancer-testis antigens (CTA) in intrahepatic cholagiocarcinoma

Background

Cancer-testis antigens (CTAs) are suitable targets for cancer-specific immunotherapy. The aim of the study is to investigate the expression of CTAs in intrahepatic cholagiocarcinoma (IHCC) and evaluate their potential therapeutic values.

Methods

Eighty-nine IHCC patients were retrospectively assessed for their expression of CTAs and HLA Class I by immunohistochemistry using the following antibodies: MA454 recognizing MAGE-A1, 57B recognizing multiple MAGE-A (MAGE-A3/A4), E978 recognizing NY-ESO-1, and EMR8-5 recognizing HLA class I. The clinicopathological and prognostic significance of individual CTA markers and their combination were further evaluated.

Results

The expression rates of MAGE-A1, MAGE-A3/4 and NY-ESO-1 were 29.2%, 27.0% and 22.5%, respectively. The concomitant expression of CTAs and HLA class I antigen was observed in 33.7% of the IHCC tumors. We found that positive MAGE-3/4 expression correlated with larger tumor size (≥ 5 cm), tumor recurrence and poor prognosis. Moreover, we identified 52 cases (58.4%) of IHCC patients with at least one CTA marker expression, and this subgroup displayed a higher frequency of larger tumor size and a shorter survival than the other cases. Furthermore, expression of at least one CTA marker was also an independent prognostic factor in patients with IHCC.

Conclusion

Our data suggest that specific immunotherapy targeted CTAs might be a novel treatment option for IHCC patients.

The SSX family of cancer-testis antigens as target proteins for tumor therapy

Cancer-testis antigens (CTAs) represent an expanding class of tumor-associated proteins defined on the basis of their tissue-restricted expression to testis or ovary germline cells and frequent ectopic expression in tumor tissue. The expression of CTA in MHC class I-deficient germline cells makes these proteins particularly attractive as immunotherapeutic targets because they serve as essentially tumor-specific antigens for MHC class I-restricted CD8+ T cells. Moreover, because CTAs are expressed in many types of cancer, any therapeutic developed to target these antigens might have efficacy for multiple cancer types. Of particular interest among CTAs is the synovial sarcoma X chromosome breakpoint (SSX) family of proteins, which includes ten highly homologous family members. Expression of SSX proteins in tumor tissues has been associated with advanced stages of disease and worse patient prognosis. Additionally, both humoral and cell-mediated immune responses to SSX proteins have been demonstrated in patients with tumors of varying histological origin, which indicates that natural immune responses can be spontaneously generated to these antigens in cancer patients. The current review will describe the history and identification of this family of proteins, as well as what is known of their function, expression in normal and malignant tissues, and immunogenicity.

Frequent expression of the novel cancer testis antigen MAGE-C2/CT-10 in hepatocellular carcinoma

Cancer testis (CT) antigens are attractive targets for immunotherapy in cancer patients. Immunohistochemistry was used to study the expression of the CT antigens MAGE-C2/CT-10, MAGE-C1/CT-7, GAGE, MAGE-A4 and NY-ESO-1 in 146 hepatocellular carcinomas, 13 intrahepatic cholangiocarcinomas, 37 extrahepatic cholangiocarcinomas and 32 gallbladder carcinomas. Immunopositivity was correlated with clinicopathological parameters, MHC Class 1 expression, intratumoral CD4+, CD8+ and FOXP3+ T cells and CD163+ antigen-presenting cells. Of the 146 hepatocellular carcinomas, 34% were positive for MAGE-C2/CT-10, 12% for MAGE-C1/CT-7, 11% for GAGE and 2% for NY-ESO-1, respectively. MHC Class 1 coexpression was identified in almost all CT antigen-positive tumors. The number of intratumoral FOXP3+ regulatory T cells was increased in CT antigen-positive hepatocellular carcinomas (p<0.004), suggesting inhibition of immune response in such tumors. Furthermore, MAGE-C1/CT-7 and GAGE positivity was correlated with reduced overall survival in patients with hepatocellular carcinoma (p=0.03 and 0.01, respectively). Four (13%) gallbladder carcinomas stained positive for MAGE-C2/CT-10, of which 1 tumor (3%) was also positive for NY-ESO-1 and GAGE. CT antigens were not expressed in intra- and extrahepatic cholangiocarcinomas. Our results suggest that MAGE-C2/CT-10 may be a good candidate for peptide vaccination in patients with hepatocellular carcinoma.

Directions in the immune targeting of cancer: lessons learned from the cancer-testis Ag NY-ESO-1

Since the early 1990s, numerous cancer Ag have been defined and for a handful of these there is now some clinical experience, which has made it possible to assess their value as targets for cancer immunotherapy. The cancer-testis Ag have been particularly attractive because their expression is limited to cancer and virtually no non-malignant cells apart from germ cells and trophoblast. Among these, NY-ESO-1 has been the focus of our attention. The exceptional immunogenicity of this Ag coupled with its widespread distribution among many cancer types make it a very good vaccine candidate, with the potential to be used in vaccines against many types of malignancies. This article reviews emerging knowledge about the biology of NY-ESO-1 and experience with the early clinical development of vaccines directed against NY-ESO-1. These early studies have yielded a wealth of information about the immunology of NY-ESO-1 and set the scene for future clinical strategies for immune targeting of cancer.

The clinical significance of MAGEA3 expression in pancreatic cancer

The MAGEA gene family that encodes cancer testis antigens is differentially expressed in many cancers. Though MAGEA3 expression has been detected in gastrointestinal malignancies, its role in pancreatic ductal adenocarcinoma (PDAC) has not been well established. We assessed 57 patients who underwent intent-to-cure surgery for PDAC. Total RNA from paraffin-embedded pancreatic tumors was extracted and assessed for MAGEA3 gene expression by an optimized probe-based quantitative real-time RT-PCR (qRT) assay. MAGEA3 gene expression was detected by qRT in 25 (44%) patients. For the entire cohort, detection of MAGEA3 expression was associated with significantly decreased overall survival (median, 16 vs 33 months; log-rank, p = 0.032). When clinicopathologic factors, including age, gender, stage, tumor extent, lymph node metastasis, tumor grade, perineural invasion and lymphovascular invasion were assessed by univariate analysis, MAGEA3 gene expression and tumor grade were significant prognostic factors for poor survival (HR 2.1, 95% CI: 1.0-4.4, p = 0.041; and HR 3.7, 95% CI: 1.8-7.6, p = 0.0004, respectively). Immunohistochemistry (IHC) was performed and confirmed MAGEA3 protein in PDAC specimens. In conclusion, MAGEA3 is differentially expressed in patients with PDAC; its expression correlates with significantly worse survival. Molecular assessment for MAGEA3 should be considered to improve prognostic evaluation and to identify eligible patients for potential immune-based therapy.