Monophasic and biphasic synovial sarcomas abundantly express cancer/testis antigen NY-ESO-1 but not MAGE-A1 or CT7

Synovial sarcoma: recent discoveries as a roadmap to new avenues for therapy

Oncogenesis in synovial sarcoma is driven by the chromosomal translocation t(X,18; p11,q11), which generates an in-frame fusion of the SWI/SNF subunit SS18 to the C-terminal repression domains of SSX1 or SSX2. Proteomic studies have identified an integral role of SS18-SSX in the SWI/SNF complex, and provide new evidence for mistargeting of polycomb repression in synovial sarcoma. Two recent in vivo studies are highlighted, providing additional support for the importance of WNT signaling in synovial sarcoma: One used a conditional mouse model in which knockout of β-catenin prevents tumor formation, and the other used a small-molecule inhibitor of β-catenin in xenograft models.

SIGNIFICANCE

Synovial sarcoma appears to arise from still poorly characterized immature mesenchymal progenitor cells through the action of its primary oncogenic driver, the SS18-SSX fusion gene, which encodes a multifaceted disruptor of epigenetic control. The effects of SS18-SSX on polycomb-mediated gene repression and SWI/SNF chromatin remodeling have recently come into focus and may offer new insights into the basic function of these processes. A central role for deregulation of WNT-β-catenin signaling in synovial sarcoma has also been strengthened by recent in vivo studies. These new insights into the the biology of synovial sarcoma are guiding novel preclinical and clinical studies in this aggressive cancer.

A pilot trial using lymphocytes genetically engineered with an NY-ESO-1-reactive T-cell receptor: long-term follow-up and correlates with response

PURPOSE

Although adoptive cell therapy can be highly effective for the treatment of patients with melanoma, the application of this approach to the treatment of other solid tumors has been limited. The observation that the cancer germline (CG) antigen NY-ESO-1 is expressed in 70% to 80% and in approximately 25% of patients with synovial cell sarcoma and melanoma, respectively, prompted us to perform this first-in-man clinical trial using the adoptive transfer of autologous peripheral blood mononuclear cells that were retrovirally transduced with an NY-ESO-1-reactive T-cell receptor (TCR) to heavily pretreated patients bearing these metastatic cancers.

EXPERIMENTAL DESIGN

HLA-*0201 patients with metastatic synovial cell sarcoma or melanoma refractory to standard treatments and whose cancers expressed NY-ESO-1 received autologous TCR-transduced T cells following a lymphodepleting preparative chemotherapy. Response rates using Response Evaluation Criteria in Solid Tumors (RECIST), as well as immunologic correlates of response, are presented in this report.

RESULTS

Eleven of 18 patients with NY-ESO-1(+) synovial cell sarcomas (61%) and 11 of 20 patients with NY-ESO-1(+) melanomas (55%) who received autologous T cells transduced with an NY-ESO-1-reactive TCR demonstrated objective clinical responses. The estimated overall 3- and 5-year survival rates for patients with synovial cell sarcoma were 38% and 14%, respectively, whereas the corresponding estimated survival rates for patients with melanoma were both 33%.

CONCLUSIONS

The adoptive transfer of autologous T cells transduced with a retrovirus encoding a TCR against an HLA-A*0201 restricted NY-ESO-1 epitope can be an effective therapy for some patients bearing synovial cell sarcomas and melanomas that are refractory to other treatments.

Adoptive immunotherapy against sarcomas

INTRODUCTION

Conventional treatments reached an unsatisfactory therapeutic plateau in the treatment of advanced unresectable bone and soft tissue sarcomas that remain an unsolved medical need. Several evidences support the concept that adoptive immunotherapy may effectively integrate within the complex and multidisciplinary treatment of sarcomas.

AREAS COVERED

In this work we reviewed adoptive immunotherapy strategies that have been explored in sarcoma settings, with specific focus on issues related to their clinic transferability. We schematically divided approaches based on T lymphocytes specific for MHC-restricted tumor-associated antigens or relying on MHC-independent immune effectors such as natural killer (NK), cytokine-induced killer (CIK) or γδ T cells.

EXPERT OPINION

Preclinical findings and initial clinical reports showed the potentialities and drawbacks of different adoptive immunotherapy strategies. The expansion of tumor infiltrating lymphocytes is difficult to be reproduced outside melanoma. Genetically redirected T cells appear to be a promising option and initial reports are encouraging against patients with sarcomas. Adoptive immunotherapy with MHC-unrestricted effectors such as NK, CIK or γδ T cells has recently shown great preclinical potential in sarcoma setting and biologic features that may favor clinical transferability. Combination of different immunotherapy approaches and integration with conventional treatments appear to be key issues for successful designing of next clinical trials.

Tetramer guided, cell sorter assisted production of clinical grade autologous NY-ESO-1 specific CD8(+) T cells

Background

Adoptive T cell therapy represents an attractive modality for the treatment of patients with cancer. Peripheral blood mononuclear cells have been used as a source of antigen specific T cells but the very low frequency of T cells recognizing commonly expressed antigens such as NY-ESO-1 limit the applicability of this approach to other solid tumors. To overcome this, we tested a strategy combining IL-21 modulation during in vitro stimulation with first-in-class use of tetramer-guided cell sorting to generate NY-ESO-1 specific cytotoxic T lymphocytes (CTL).

Methods

CTL generation was evaluated in 6 patients with NY-ESO-1 positive sarcomas, under clinical manufacturing conditions and characterized for phenotypic and functional properties.

Results

Following in vitro stimulation, T cells stained with NY-ESO-1 tetramer were enriched from frequencies as low as 0.4% to >90% after single pass through a clinical grade sorter. NY-ESO-1 specific T cells were generated from all 6 patients. The final products expanded on average 1200-fold to a total of 36 billion cells, were oligoclonal and contained 67-97% CD8⁺, tetramer⁺ T cells with a memory phenotype that recognized endogenous NY-ESO-1.

Conclusion

This study represents the first series using tetramer-guided cell sorting to generate T cells for adoptive therapy. This approach, when used to target more broadly expressed tumor antigens such as WT-1 and additional Cancer-Testis antigens will enhance the scope and feasibility of adoptive T cell therapy.

Electronic supplementary material

The online version of this article (doi:10.1186/s40425-014-0036-y) contains supplementary material, which is available to authorized users.

Synovial sarcoma: defining features and diagnostic evolution

Synovial sarcoma (SS) is a malignant mesenchymal neoplasm with variable epithelial differentiation, with a propensity to occur in young adults and which can arise at almost any site. It is generally viewed and treated as a high-grade sarcoma. As one of the first sarcomas to be defined by the presence of a specific chromosomal translocation leading to the production of the SS18-SSX fusion oncogene, it is perhaps the archetypal "translocation-associated sarcoma," and its translocation remains unique to this tumor type. Synovial sarcoma has a variety of morphologic patterns, but its chief forms are the classic biphasic pattern, of glandular or solid epithelial structures with monomorphic spindle cells and the monophasic pattern, of fascicles of spindle cells with only immunohistochemical or ultrastructural evidence of epithelial differentiation. However, there is significant morphologic heterogeneity and overlap with a variety of other neoplasms, which can cause diagnostic challenge, particularly as the immunoprofile is varied, SS18-SSX is not detected in 100% of SSs, and they may occur at unusual sites. Correct diagnosis is clinically important, due to the relative chemosensitivity of SS in relation to other sarcomas, for prognostication and because of the potential for treatment with specific targeted therapies in the near future. We review SS, with emphasis on the diagnostic spectrum, recent immunohistochemical and genetic findings, and the differential diagnosis.

MAGE-specific T cells detected directly ex-vivo correlate with complete remission in metastatic breast cancer patients after sequential immune-endocrine therapy

Studies suggest that conventional cancer therapies given after immunotherapy (IT) can boost antitumor immunity and possibly improve response rates and progression-free survival. We report two cases of metastatic breast cancer with durable complete responses (CRs) after sequential IT and endocrine therapy. Immune analyses of these long-term disease-free breast cancer patients previously treated with imiquimod (IMQ) suggest in-situ vaccination is achieved by topical application of the TLR-7 agonist directly onto tumors. Furthermore, IT-induced antigen-specific T cells were expanded by subsequent endocrine therapy and correlated with response, persisting > 2 years. Our findings therefore suggest that the induction/boosting of polyfunctional tumor antigen-specific T in response to sequential immune endocrine therapy and detected directly ex-vivo can serve as a peripheral blood biomarker for true clinical benefit.

Cellular immunotherapy for pediatric solid tumors

Substantial progress has been made in the treatment of pediatric solid tumors over the past 4 decades. However, children with metastatic and or recurrent disease continue to do poorly despite the aggressive multi-modality conventional therapies. The increasing understanding of the tumor biology and the interaction between the tumor and the immune system over the recent years have led to the development of novel immune-based therapies as alternative options for some of these high-risk malignancies. The safety and anti-tumor efficacy of various tumor vaccines and tumor-antigen specific immune cells are currently being investigated for various solid tumors. In early clinical trials, most of these cellular therapies have been well tolerated and have shown promising clinical responses. Although substantial work is being done in this field, the available knowledge for pediatric tumors remains limited. We review the contemporary early phase cell-based immunotherapy efforts for pediatric solid tumors and discuss the rationale and the challenges thereof.

NY-ESO-1 expression is tightly linked to TMPRSS2-ERG fusion in prostate cancer

BACKGROUND

NY-ESO-1 has been suggested as therapeutic cancer vaccine in prostate cancer. This study was undertaken to explore the relationship of NY-ESO-1 with tumor phenotype, biochemical recurrence, and molecular subgroups in hormone-naive prostate cancers.

METHODS

NY-ESO-1 immunohistochemistry was analyzed on a tissue microarray containing 11,152 prostate cancer samples. Results were compared to clinically follow-up data, ERG status, and deletions on PTEN, 3p13, 5q21, and 6q15.

RESULTS

NY-ESO-1 expression was absent in benign prostate glands. In prostate cancer, NY-ESO-1 positivity was found 8.8% of our 8,761 interpretable tumors including 5.8% with weak, 2.5% with moderate, and 0.5% with strong expression. There was a threefold higher rate of NY-ESO-1 expression in ERG fusion positive tumors than in ERG negative cancers (P < 0.0001). There was a significant association with early PSA recurrence, which was largely limited to ERG positive cancers. Within the ERG positive subgroup, high NY-ESO-1 expression was associated with early biochemical recurrence (P = 0.0002) and high Gleason grade (P < 0.0001). In ERG negative cancers, NY-ESO-1 expression was also linked to PTEN (P = 0.0012) and 6q15 deletions (P = 0.0005).

CONCLUSIONS

Our observations indicate a tight link of NY-ESO-1 expression to ERG activation and (to a lesser extent) PTEN- and 6q15-deletions in prostate cancer. The impact of these interactions on the likelihood of response to immunotherapy is unclear. The prognostic impact of NY-ESO-1 expression is little and not independent of histologic variables.

Molecular docking and fluorescence characterization of benzothieno[3,2-d]pyrimidin-4-one sulphonamide thio-derivatives, a novel class of selective cyclooxygenase-2 inhibitors

The aims of this study were: (i) to explore the structure-activity relationship of some new anti-inflammatory benzothieno[3,2-d]pyrimidin-4-one sulphonamide thio-derivatives 1–11; and (ii) to evaluate the possibility of using the most active compounds as fluorescent probes to determine tumours or their progression. Therefore, to know the precise mechanism by which these compounds interact with cyclooxygenase (COX)-2 enzyme, a molecular docking study was carried out; to assess spectroscopic characteristics, their absorption and emission properties were determined. The results demonstrated that some derivatives of benzothieno[3,2-d] pyrimidine exhibit interesting anti-inflammatory properties related to interactions with active sites of COX-2 and are fluorescent. The antipyrine-bearing compound 4 displayed high COX-2 affinity (ΔG = −9.4) and good fluorescent properties (Φ_fl = 0.032). Thus, some members of this new class of anti-inflammatory may be promising for fluorescence imaging of cancer cells that express the COX-2 enzyme. Further in vitro and in vivo studies are needed to confirm this hypothesis.

Sarcoma immunotherapy: past approaches and future directions

Sarcomas are heterogeneous malignant tumors of mesenchymal origin characterized by more than 100 distinct subtypes. Unfortunately, 25–50% of patients treated with initial curative intent will develop metastatic disease. In the metastatic setting, chemotherapy rarely leads to complete and durable responses; therefore, there is a dire need for more effective therapies. Exploring immunotherapeutic strategies may be warranted. In the past, agents that stimulate the immune system such as interferon and interleukin-2 have been explored and there has been evidence of some clinical activity in selected patients. In addition, many cancer vaccines have been explored with suggestion of benefit in some patients. Building on the advancements made in other solid tumors as well as a better understanding of cancer immunology provides hope for the development of new and exciting therapies in the treatment of sarcoma. There remains promise with immunologic checkpoint blockade antibodies. Further, building on the success of autologous cell transfer in hematologic malignancies, designing chimeric antigen receptors that target antigens that are over-expressed in sarcoma provides a great deal of optimism. Exploring these avenues has the potential to make immunotherapy a real therapeutic option in this orphan disease.

Decitabine facilitates immune recognition of sarcoma cells by upregulating CT antigens, MHC molecules, and ICAM-1

Rhabdomyosarcoma, osteosarcoma, and Ewing's sarcoma are the most common types of sarcoma in children. Despite standard therapy, nearly one third of the patients with Ewing's sarcoma relapse, and there are limited options with curative potential. Immunotherapy is a promising approach as it can target tumor-specific antigens that are specifically expressed on tumors while sparing non-malignant cells. We have demonstrated that a demethylating chemotherapeutic drug, 5-aza-2'-deoxycytidine (decitabine, DAC) can upregulate the expression of cancer-testis (CT) antigens, MHC molecules, and intracellular cell adhesion molecule-1 on pediatric sarcoma cell lines, resulting in enhanced killing of tumor cells by CT antigen-specific cytotoxic T lymphocytes derived from pediatric sarcoma patients. A significant increase in the mRNA expression levels of MAGE-A1 and MAGE-A3 were found in 70 %, and NY-ESO-1 in 80 % of the sarcoma lines following exposure to pharmacological levels of DAC. The high expression levels of MAGE-A1, MAGE-A3, and NY-ESO-1 were sustained in sarcoma lines and primary tumor lines over 30 days after the cessation of DAC. Furthermore, DAC treatment induced upregulation of MAGE-A1, MAGE-A3, or NY-ESO-1 protein expression in seven of nine lines studied. These studies show that demethylating chemotherapy could be combined with CT antigen-directed immunotherapy for treating pediatric sarcoma.

Detection of cancer/testis antigens as a diagnostic tool in routine pathology practice

Most of the studies on cancer/testis (CT) antigens performed to date have focused on their potential value as targets for immunotherapy. Several recent studies, however, revealed that CT antigens might represent useful tools for diagnostic pathology, in particular for the identification of squamous cell carcinoma and related pre-malignant lesions, as well as specific types of sarcoma.

Novel treatment targets in sarcoma: more than just the GIST

Sarcomas are rare tumors comprising a heterogeneous group of more than 50 histologic subtypes, the majority of which do not respond well to cytotoxic chemotherapy. This has fueled research into the distinct molecular mechanisms of tumorigenesis and disease progression for various sarcoma subtypes. Gastrointestinal stromal tumors and liposarcomas are presented as paradigms of molecular classification that have led to the rational development of novel therapeutic strategies for those tumors. Recent advances in understanding of growth signaling pathways, metabolic reprogramming, and immune therapy have identified new treatment targets for many sarcomas. These investigations will form the foundation for further improvements in our ability to care for patients with these tumors and may offer clinical insights into a wide range of other tumors.

NY-ESO-1 is a sensitive and specific immunohistochemical marker for myxoid and round cell liposarcomas among related mesenchymal myxoid neoplasms

Myxoid and round cell liposarcomas constitute approximately one-third of all liposarcomas, a relatively common group of fat-derived soft tissue sarcomas. The histomorphology is a continuum between highly differentiated myxoid and poorly differentiated round cell components. The gold standard of diagnosis is dependent on histomorphology and/or identification of t(12;16)(q13;p11) translocation by cytogenetics or demonstration of DDIT3 rearrangements by fluorescence in situ hybridization. There are currently no diagnostic immunohistochemical stains available. The broad range of myxoid neoplasms in the differential diagnosis includes a variety of sarcomas. Given the notable differences in disease biology among myxoid neoplasms, which range from benign to aggressive, an accurate diagnosis is imperative for proper treatment and prognostication. Prompted by our recent study showing frequent expression of the cancer testis antigen NY-ESO-1 in myxoid and round cell liposarcomas, we sought to evaluate the utility of NY-ESO-1 as an immunohistochemical marker for myxoid and round cell liposarcoma among mesenchymal myxoid neoplasms within the differential diagnosis. Formalin-fixed, paraffin-embedded blocks were obtained for the following mesenchymal myxoid neoplasms (n=138): myxoid and round cell liposarcoma (n=38); well-differentiated liposarcoma (n=12); lipoma (n=20; 4 with myxoid change); extra-cardiac soft tissue myxoma (n=39); extraskeletal myxoid chondrosarcoma (n=12); myxofibrosarcoma (n=10: 5 low grade, 2 intermediate grade, 3 high grade); and low-grade fibromyxoid sarcoma (n=7). Utilizing standard immunohistochemistry protocols, full sections were stained with NY-ESO-1 (clone E978), and staining was assessed for intensity (1-2+), percentage of tumor positivity, and location. In all, 36/38 (95%) of the myxoid and round cell liposarcomas demonstrated NY-ESO-1 immunoreactivity. The majority of the positive cases (34/36; 94%) showed strong, homogenous staining (>50% tumor positivity), and two cases (6%) showed weak (1+ intensity), patchy staining (20-30% tumor positivity). Immunoreactivity was predominantly cytoplasmic. All the other neoplasms evaluated were negative for NY-ESO-1. NY-ESO-1 appears to be a sensitive and a specific marker for myxoid and round cell liposarcoma among mesenchymal myxoid neoplasms. The assessment of NY-ESO-1 expression by immunohistochemistry in the appropriate setting provides a cheaper, faster, and more accessible confirmatory test.

Phase II study of personalized peptide vaccination for refractory bone and soft tissue sarcoma patients

Refractory bone and soft tissue sarcomas are challenging diseases to treat because of their robustness to chemotherapy. Although cancer vaccines have the potential to become an attractive treatment modality, their progress has been hampered by the presence of many subtypes of sarcomas and different human leukocyte antigen (HLA)‐types. We investigated whether personalized peptide vaccination (PPV) would be feasible for the vast majority of sarcoma patients. Twenty refractory bone and soft tissue sarcoma patients with nine different subtypes and 11 different HLA‐class IA phenotypes were enrolled in this study. A maximum of four HLA‐matched peptides showing higher peptide‐specific IgG responses in pre‐vaccination plasma were selected from 31 pooled peptide candidates applicable for the HLA‐A2, ‐A3, ‐A11, ‐A24, ‐A26, ‐A31, and ‐A33 types, and were subcutaneously administered weekly for 6 weeks and bi‐weekly thereafter. Measurement of peptide‐specific CTL and IgG responses along with other laboratory analyses were conducted before and after vaccination. No patients were excluded by either sarcoma subtypes or different HLA‐types. No severe adverse events associated with PPV were observed in any patients. Peptide‐specific immunological boosting was observed in the post‐vaccination samples from the majority of patients. Tumor reduction of the lung metastasis and a long stable disease was observed in each case, and the median overall survival time of the 20 cases was 9.6 months. Taken together, PPV could be feasible for the vast majority of refractory sarcoma patients because of the safety and higher rates of immunological responses regardless of the presence of different sarcoma subtypes and various HLA‐types.

Cancer regression and neurological toxicity following anti-MAGE-A3 TCR gene therapy

Nine cancer patients were treated with adoptive cell therapy using autologous anti-MAGE-A3 T-cell receptors (TCR)-engineered T cells. Five patients experienced clinical regression of their cancers including 2 on-going responders. Beginning 1-2 days postinfusion, 3 patients (#'s 5, 7, and 8) experienced mental status changes, and 2 patients (5 and 8) lapsed into comas and subsequently died. Magnetic resonance imagining analysis of patients 5 and 8 demonstrated periventricular leukomalacia, and examination of their brains at autopsy revealed necrotizing leukoencephalopathy with extensive white matter defects associated with infiltration of CD3(+)/CD8(+) T cells. Patient 7, developed Parkinson-like symptoms, which resolved over 4 weeks and fully recovered. Immunohistochemical staining of patient and normal brain samples demonstrated rare positively staining neurons with an antibody that recognizes multiple MAGE-A family members. The TCR used in this study recognized epitopes in MAGE-A3/A9/A12. Molecular assays of human brain samples using real-time quantitative-polymerase chain reaction, Nanostring quantitation, and deep-sequencing indicated that MAGE-A12 was expressed in human brain (and possibly MAGE-A1, MAGE-A8, and MAGE-A9). This previously unrecognized expression of MAGE-A12 in human brain was possibly the initiating event of a TCR-mediated inflammatory response that resulted in neuronal cell destruction and raises caution for clinical applications targeting MAGE-A family members with highly active immunotherapies.

Cancer testis antigen and immunotherapy

The identification of cancer testis (CT) antigens has been an important advance in determining potential targets for cancer immunotherapy. Multiple previous studies have shown that CT antigen vaccines, using both peptides and dendritic cell vaccines, can elicit clinical and immunologic responses in several different tumors. This review details the expression of melanoma antigen family A, 1 (MAGE-A1), melanoma antigen family A, 3 (MAGE-A3), and New York esophageal squamous cell carcinoma-1 (NY-ESO-1) in various malignancies, and presents our current understanding of CT antigen based immunotherapy.

Characterization of T-cell receptors directed against HLA-A*01-restricted and C*07-restricted epitopes of MAGE-A3 and MAGE-A12

The ability of T cells that have been genetically engineered to express T-cell receptors (TCRs) directed against tumor antigens to mediate tumor regression has been demonstrated in several clinical trials. These TCRs have primarily targeted HLA-A*0201-restricted TCRs, as approximately 50% of whites, who represent the predominant population of patients who develop melanomas, expresses this HLA class I allele. These therapies could be extended to additional patients through the use of TCRs that target epitopes that are presented by additional class I alleles that are prevalent in this population such as HLA-C*07 and HLA-A*01, which are expressed by approximately 50% and 30% of the patient population respectively. Therefore, 2 TCRs that recognize an epitope of MAGE-A12 in the context of HLA-C*07 and 2 TCRs that recognize an epitope of MAGE-A3 in the context of HLA-A*01 were isolated from tumor-reactive T-cell clones and cloned in a recombinant retroviral expression vector. Comparative studies indicated that one of the 2 MAGE-A3-reactive TCRs and one of the 2 MAGE-A12-reactive TCRs were superior to the additional TCRs in conferring transduced peripheral blood mononuclear cells with the capacity to recognize a broad array of antigen and MHC-positive target cells. These results provide support for the use of these TCRs in cancer adoptive immunotherapy trials.

A Pilot Study of Anti-CTLA4 Antibody Ipilimumab in Patients with Synovial Sarcoma

Background. Patients with recurrent synovial sarcomas have few options for systemic therapy. Since they express large amounts of endogenous CT (cancer testis) antigens such as NY-ESO-1, we investigated the clinical activity of single agent anti-CTLA4 antibody ipilimumab in patients with advanced or metastatic synovial sarcoma. Methods. A Simon two-stage phase II design was used to determine if there was sufficient activity to pursue further. The primary endpoint was tumor response rate by RECIST 1.0. Patients were treated with ipilimumab 3 mg/kg intravenously every 3 weeks for three cycles and then restaged. Retreatment was possible for patients receiving an extra three-week break from therapy. Sera and peripheral blood mononuclear cells were collected before and during therapy to assess NY-ESO-1-specific immunity. Results. Six patients were enrolled and received 1–3 cycles of ipilimumab. All patients showed clinical or radiological evidence of disease progression after no more than three cycles of therapy, for a RECIST response rate of 0%. The study was stopped for slow accrual, lack of activity, and lack of immune response. There was no evidence of clinically significant either serologic or delayed type hypersensitivity responses to NY-ESO-1 before or after therapy. Conclusion. Despite high expression of CT antigens by synovial sarcomas of patients treated in this study, there was neither clinical benefit nor evidence of anti-CT antigen serological responses. Assessment of the ability of synovial sarcoma cell lines to present cancer-germ cell antigens may be useful in determining the reason for the observed lack of immunological or clinical activity.

The cancer-testis antigen NY-ESO-1 is highly expressed in myxoid and round cell subset of liposarcomas

Liposarcomas are a heterogenous group of fat-derived sarcomas, and surgery with or without chemoradiation therapy remains the main stay of treatment. NY-ESO-1 is a cancer-testis antigen expressed in various cancers where it can induce both cellular and humoral immunity. Immunotherapy has shown promise in clinical trials involving NY-ESO-1-expressing tumors. Gene expression studies have shown upregulation of the gene for NY-ESO-1, CTAG1B, in myxoid and round cell liposarcomas. Herein, we evaluated the expression of NY-ESO-1 among liposarcoma subtypes by quantitative real-time PCR, western blot analysis, and immunohistochemistry. Frozen tissue for quantitative real-time PCR and western blot analysis was obtained for the following liposarcoma subtypes (n=15): myxoid and round cell (n=8); well-differentiated (n=4), and dedifferentiated (n=3). Formalin-fixed paraffin-embedded blocks were obtained for the following liposarcoma subtypes (n=44): myxoid and round cell (n=18); well-differentiated (n=10); dedifferentiated (n=10); and pleomorphic (n=6). Full sections were stained with monoclonal antibody NY-ESO-1, and staining was assessed for intensity (1-3+), percentage of tumor positivity, and location. In all, 7/8 (88%) and 16/18 (89%) myxoid and round cell expressed CTAG1B and NY-ESO-1 by quantitative real-time PCR and immunohistochemistry, respectively. Western blot correlated with mRNA expression levels. By immunohistochemistry, 94% (15/16) of positive cases stained homogenously with 2-3+ intensity. Also, 3/6 (50%) pleomorphic liposarcomas demonstrated a range of staining: 1+ intensity in 50% of cells; 2+ intensity in 5% of cells; and 3+ intensity in 90% of cells. One case of dedifferentiated liposarcoma showed strong, diffuse staining (3+ intensity in 75% of cells). Our study shows that both CTAG1B mRNA and protein are overexpressed with high frequency in myxoid and round cell liposarcoma, enabling the potential use of targeted immunotherapy in the treatment of this malignancy.

Enhanced activation of human dendritic cells by silencing SOCS1 and activating TLRs simultaneously

There was established evidence that silencing the attenuator and activating the TLRs could activate the dendritic cells in synergic effects. In this study, we constructed a plasmid, namely pshS1NH, which encodes SOCS1-shRNA, NY-ESO-1-MAGE3 (HLA-A2*0201) fusion antigen and secretory HMGB1, an agent used to modify dendritic cells (DCs), aiming to generate potent DC vaccine against tumors. The SOCS1-shRNA could efficiently downregulate the expression of SOCS1, as indicated by real-time RT-PCR and Western blot. The fusion antigen was detected in the pshS1NH-DCs by PCR and Western blot. Simultaneously, HMGB1 level in the pshS1NH-DCs culture media was significantly higher than that in the control DCs culture media. Levels of Th1 cytokines in pshS1NH-DCs culture media, such as IL-1β, IL-6, TNF-α and IL-12p70, were dramatically higher than those in control DCs culture media. In addition, lymphocytes co-cultured with pshS1NH-DCs secreted dramatically higher level of IFN-γ, whereas no difference was detected in IL-4 levels. Taken together, these data suggest that pshS1NH-DCs may be a potential adjuvant immunotherapy for cancers in clinical applications.

NY-ESO-1 expression in synovial sarcoma and other mesenchymal tumors: significance for NY-ESO-1-based targeted therapy and differential diagnosis

A promising targeted therapy against NY-ESO-1 (CTAG 1B) using genetically modified T-cells in synovial sarcomas was recently demonstrated in a clinical trial at the NCI. To investigate the role of NY-ESO-1 immunohistochemistry in patient selection and gain better insight into the incidence of NY-ESO-1 expression in synovial sarcomas and other mesenchymal tumors, we evaluated NY-ESO-1 expression by immunohistochemistry in 417 tumors. This collection of samples included: 50 SS18/SSX1/2 fusion positive synovial sarcomas, 155 gastrointestinal stromal tumors (GIST), 135 other spindle cell sarcomas as well as 77 other sarcomas (chondrosarcoma, osteosarcoma, dedifferentiated liposarcoma, alveolar soft part sarcoma, rhabdomyosarcoma, angiosarcoma, malignant mesothelioma, and Ewing's sarcoma). We report that 76% of synovial sarcomas expressed NY-ESO-1 in a strong and diffuse pattern (2-3+, >50-70% of tumor cells). In contrast, only rare cases of other spindle cell mesenchymal tumor expressed NY-ESO-1 (GIST (2/155), malignant peripheral nerve sheath tumors (1/34), and dermatofibrosarcoma protuberans (2/20)). Individual cases of other sarcomas (angiosarcoma, malignant mesothelioma, chondrosarcoma, osteosarcoma, dedifferentiated liposarcoma, alveolar soft part sarcoma, and Ewing's sarcoma) were positive for NY-ESO-1. However, no positive cases were identified amongst our cohort of leiomyosarcomas (0/24), hemangiopericytoma/solitary fibrous tumors (0/40), and cellular schwannomas (0/17). In summary, we find that NY-ESO-1 is strongly and diffusely expressed in a majority of synovial sarcomas, but only rarely in other mesenchymal lesions. Beyond its role in patient selection for targeted therapy, immunohistochemistry for NY-ESO-1 may be diagnostically useful for the distinction of synovial sarcoma from other spindle cell neoplasms.

NY-ESO-1 is a ubiquitous immunotherapeutic target antigen for patients with myxoid/round cell liposarcoma

BACKGROUND

Myxoid/round cell liposarcoma (MRCL) is the second most common liposarcoma subtype, accounting for >33% of liposarcomas and approximately 10% of all soft tissue sarcomas. Although MRCL is a chemosensitive subtype, patients with metastatic disease have a poor outcome. NY-ESO-1 is a cancer-testis antigen (also known as cancer germ cell antigen) that has been successfully targeted in vaccine trials and in adoptive T-cell therapy trials for the treatment of several solid tumors.

METHODS

The authors investigated the feasibility of targeting NY-ESO-1 in patients with MRCL by evaluating the prevalence of NY-ESO-1 expression in tumors using immunohistochemistry and quantitative reverse transcriptase-polymerase chain reaction analysis. NY-ESO-1-specific tumor recognition by NY-ESO-1-specific T-cells also was analyzed using a chromium release assay.

RESULTS

A search of the University of Washington Sarcoma Tissue Bank identified paraffin-embedded tumor samples from 25 patients with MRCL. NY-ESO-1 expression was observed in every MRCL tumor assessed (100%); in 18 tumors (72%), staining was homogenous. In all but 2 tumors, staining was sufficiently robust (2+) that such patients would be eligible for clinical trials of NY-ESO-1-directed therapy. By using NY-ESO-1 specific, CD8-positive T-cells, the in vitro sensitivity of myxoid liposarcoma cell lines to antigen-specific lysis was demonstrated.

CONCLUSIONS

The current results establish NY-ESO-1 as an important target antigen for the treatment of patients with MRCL.

Searching for molecular targets in sarcoma

Sarcoma are about 1% of cancers. Within that 1% are widely varied tumors now divided into types and subtypes. Sarcoma occur in patients of all ages with frequency spread evenly over the human age range. Although the specific cell of origin of many sarcoma remains unclear, sarcoma are all tumors of mesenchymal origin. The mesenchymal stem cell, a pluripotent cell, which gives rise to varied differentiated cells including osteocytes, adipocytes, chondrocytes, muscle cells, fibroblasts, neural cells and stromal cells, is the most likely ultimate cell of origin for sarcoma. When mesenchymal stem cell genetics go awry and malignant transformation occurs sarcoma including osteosarcoma, Ewing's sarcoma, chondrosarcoma, rhabdomyosarcoma, synovial sarcoma fibrosarcoma, liposarcoma and many others can initiate. Our knowledge of sarcoma genetics is increasing rapidly. Two general groups, sarcoma arising from chromosomal translocations and sarcoma with very complex genetics, can be identified. Genes that are frequently mutated in sarcoma include TP53, NF1, PIK3CA, HDAC1, IDH1 and 2, KDR, KIT and MED12. Genes that are frequently amplified in sarcoma include CDK4, YEATS4, HMGA2, MDM2, JUN, DNM3, FLT4, MYCN, MAP3K5, GLI1 and the microRNAs miR-214 and miR-199a2. Genes that are upregulated in sarcoma include MUC4, CD24, FOXL1, ANGPTL2, HIF1α, MDK, cMET, TIMP-2, PRL, PCSK1, IGFR-1, TIE1, KDR, TEK, FLT1 and several microRNAs. While some alterations occur in specific subtypes of sarcoma, others cross several sarcoma types. Discovering and developing new therapeutic approaches for these relentless diseases is critical. The detailed knowledge of sarcoma genetics may allow development of sarcoma subtype-targeted therapeutics.

Immunotherapy targets in pediatric cancer

Immunotherapy for cancer has shown increasing success and there is ample evidence to expect that progress gleaned in immune targeting of adult cancers can be translated to pediatric oncology. This manuscript reviews principles that guide selection of targets for immunotherapy of cancer, emphasizing the similarities and distinctions between oncogene-inhibition targets and immune targets. It follows with a detailed review of molecules expressed by pediatric tumors that are already under study as immune targets or are good candidates for future studies of immune targeting. Distinctions are made between cell surface antigens that can be targeted in an MHC independent manner using antibodies, antibody derivatives, or chimeric antigen receptors versus intracellular antigens which must be targeted with MHC restricted T cell therapies. Among the most advanced immune targets for childhood cancer are CD19 and CD22 on hematologic malignancies, GD2 on solid tumors, and NY-ESO-1 expressed by a majority of synovial sarcomas, but several other molecules reviewed here also have properties which suggest that they too could serve as effective targets for immunotherapy of childhood cancer.

MAGE-A1, MAGE-A3, and NY-ESO-1 can be upregulated on neuroblastoma cells to facilitate cytotoxic T lymphocyte-mediated tumor cell killing

Approximately half of patients with stage IV neuroblastoma are expected to relapse despite current therapy, and when this occurs, there is little likelihood of achieving a cure. Very few clinical trials have been conducted to determine whether cellular immune responses could be harnessed to fight this tumor, largely because potential tumor antigens for cytotoxic T lymphocytes (CTL) are limited. MAGE-A1, MAGE-A3, and NY-ESO-1 are cancer-testis (CT) antigens expressed on a number of malignant solid tumors, including neuroblastoma, but many tumor cell lines down-regulate the expression of CT antigens as well as major histocompatibility (MHC) antigens, precluding recognition by antigen-specific T cells. If expression of cancer antigens on neuroblastoma could be enhanced pharmacologically, CT antigen-specific immunotherapy could be considered for this tumor. We have demonstrated that the expression of MAGE-A1, MAGE-A3, and NY-ESO-1 can be upregulated on neuroblastoma cells following exposure to pharmacologic levels of the demethylating agent 5-aza-2'-deoxycytidine (decitabine, DAC). Expression of NY-ESO-1, MAGE-A1, or MAGE-A3 was induced in 10/10 neuroblastoma cell lines after 5 days of exposure to DAC. Culture of neuroblastoma cell lines with IFN-γ was also associated with an increased expression of either MHC Class I or II by cytofluorometry, as reported by other groups. MAGE-A1, MAGE-A3, and NY-ESO-1-specific CTL were cultured from volunteer donors by stimulating peripheral blood mononuclear cells with dendritic cells pulsed with overlapping peptide mixes derived from full-length proteins, and these CTL preferentially lysed HLA partially matched, DAC-treated neuroblastoma and glioblastoma cell lines. These studies show that demethylating chemotherapy can be combined with IFN-γ to increase the expression of CT antigens and MHC molecules on neuroblastoma cells, and pre-treatment with these agents makes tumor cell lines more susceptible to CTL-mediated killing. These data provide a basis to consider the use of demethylating chemotherapy in neuroblastoma patients, in conjunction with immune therapies that facilitate the expansion of CT antigen-specific CTL.

Treating cancer with genetically engineered T cells

Administration of ex vivo cultured, naturally occurring tumor-infiltrating lymphocytes (TILs) has been shown to mediate durable regression of melanoma tumors. However, the generation of TILs is not possible in all patients and there has been limited success in generating TIL in other cancers. Advances in genetic engineering have overcome these limitations by introducing tumor-antigen-targeting receptors into human T lymphocytes. Physicians can now genetically engineer lymphocytes to express highly active T-cell receptors (TCRs) or chimeric antigen receptors (CARs) targeting a variety of tumor antigens expressed in cancer patients. In this review, we discuss the development of TCR and CAR gene transfer technology and the expansion of these therapies into different cancers with the recent demonstration of the clinical efficacy of these treatments.

Expression and purification of cGMP grade NY-ESO-1 for clinical trials

NY-ESO-1 is a cancer testis antigen expressed in numerous cancers. Initial tests have shown its efficacy as a cancer vaccine, stimulating the body's own immune response against the invading tumor. To produce enough material for phase I clinical trials, a process using current good manufacturing practices to produce clinical grade material was developed and executed. His-tagged NY-ESO-1 was expressed in C41DE3 Escherichia coli under control of the T-7 promoter. NY-ESO-1 was produced in a 20 L fed-batch fermentation utilizing a pH-stat control scheme. The protein was then purified from inclusion bodies using a three-column process that achieved a yield of over 3.4 g and endotoxin below the detection limit of 0.005 EU/μg protein.

Tumor regression in patients with metastatic synovial cell sarcoma and melanoma using genetically engineered lymphocytes reactive with NY-ESO-1

PURPOSE

Adoptive immunotherapy using tumor-infiltrating lymphocytes represents an effective cancer treatment for patients with metastatic melanoma. The NY-ESO-1 cancer/testis antigen, which is expressed in 80% of patients with synovial cell sarcoma and approximately 25% of patients with melanoma and common epithelial tumors, represents an attractive target for immune-based therapies. The current trial was carried out to evaluate the ability of adoptively transferred autologous T cells transduced with a T-cell receptor (TCR) directed against NY-ESO-1 to mediate tumor regression in patients with metastatic melanoma and synovial cell sarcoma.

PATIENTS AND METHODS

A clinical trial was performed in patients with metastatic melanoma or metastatic synovial cell sarcoma refractory to all standard treatments. Patients with NY-ESO-1-positive tumors were treated with autologous TCR-transduced T cells plus 720,000 iU/kg of interleukin-2 to tolerance after preparative chemotherapy. Objective clinical responses were evaluated using Response Evaluation Criteria in Solid Tumors (RECIST).

RESULTS

Objective clinical responses were observed in four of six patients with synovial cell sarcoma and five of 11 patients with melanoma bearing tumors expressing NY-ESO-1. Two of 11 patients with melanoma demonstrated complete regressions that persisted after 1 year. A partial response lasting 18 months was observed in one patient with synovial cell sarcoma.

CONCLUSION

These observations indicate that TCR-based gene therapies directed against NY-ESO-1 represent a new and effective therapeutic approach for patients with melanoma and synovial cell sarcoma. To our knowledge, this represents the first demonstration of the successful treatment of a nonmelanoma tumor using TCR-transduced T cells.

Immune-based therapies for sarcoma

Immunotherapy has shown promise in a number of tumor types, but its exact role in sarcoma remains to be defined. Advanced bone and soft tissue sarcomas are challenging diseases to treat with an unmet need for effective systemic therapy. Previous reports have suggested that immune-based treatments may be effective in sarcoma, but such approaches have not yet become part of standard clinical practice. A number of sarcoma subtypes express targets known as cancer testis antigens and hence may be excellent targets for immunotherapy. This paper will focus on the recent advances and understanding of cancer testis antigens in sarcoma and also clinical data of immunotherapeutic approaches in these diseases.

Cancer/testis (CT) antigens: potential targets for immunotherapy

Cancer/testis (CT) antigens are protein antigens with normal expression restricted to adult testicular germ cells, and yet are aberrantly activated and expressed in a proportion of various types of human cancer. At least a subset of this group of antigens has been found to elicit spontaneous humoral and cell-mediated immune responses in cancer patients, raising the possibility that these antigens could be cancer vaccine targets. More than 100 CT antigen genes have been reported in the literature, with approximately 30 being members of multigene families on the X chromosome, so-called CT-X genes. Most CT-X genes are expressed at the spermatogonia stage of spermatogenesis, and their functions are mostly unknown. In cancer, the frequency of CT antigen expression is highly variable among different tumor types, but is more often expressed in high-grade late-stage cases in general. Cancer vaccine trials based on CT antigens MAGE-A3 and NY-ESO-1 are currently ongoing, and these antigens may also play a role in antigen-specific adoptive T-cell transfer and in the immunomodulation approach of cancer therapy.

Expression of GAGE family proteins in malignant melanoma

Cancer/testis antigens are considered as promising targets for immunotherapy against tumors including malignant melanoma. One group of these antigens is the GAGE antigen family. In this study, we obtained recombinant GAGE-7b protein against which a rabbit antiserum was generated. The polyclonal, monospecific antibodies were used to analyze the expression of GAGE family proteins in human melanoma tissues and cell lines. GAGE expression in melanoma cell lines ranged from 41% to 58% and in melanoma tissues from 22% to 53%. Immunohistochemical analysis of melanoma tumors revealed a rather heterogeneous expression of GAGE resulting in individual positive cells or foci of stained cells. Furthermore, we could show that autoantibodies against GAGE family proteins are detectable in 6% of melanoma patients. Besides, we first demonstrated that the expression of GAGE family proteins can be stimulated with 5'-aza-2'-deoxycytidine and trichostatin A. Through upregulation of protein expression GAGE family proteins might develop into promising targets for immunotherapy of melanoma and other tumors.

NY-ESO-1: review of an immunogenic tumor antigen

In the 9 years since its discovery, cancer-testis antigen NY-ESO-1 has made one of the fastest transitions from molecular, cellular, and immunological description to vaccine and immunotherapy candidate, already tested in various formulations in more than 30 clinical trials worldwide. Its main characteristic resides in its capacity to elicit spontaneous antibody and T-cell responses in a proportion of cancer patients. An overview of immunological findings and immunotherapeutic approaches with NY-ESO-1, as well the role of regulation in NY-ESO-1 immunogenicity, is presented here.

Preferential nuclear and cytoplasmic NY-BR-1 protein expression in primary breast cancer and lymph node metastases

PURPOSE

NY-BR-1 is a recently isolated differentiation antigen, which is expressed in normal mammary tissue and in breast cancer. However, current data are based on RT-PCR analysis and nothing is known about the presence of NY-BR-1 on a protein level. We previously generated a monoclonal antibody to NY-BR-1 to study the protein expression of NY-BR-1.

METHODS

In our immunohistochemical study, NY-BR-1 was analyzed in normal tissues, various tumor types, 124 primary breast cancers, and 37 paired lymph node metastases.

RESULTS

Among normal tissues, NY-BR-1 was present solely in ductal epithelium of the breast. In tumors, carcinoma in situ and invasive carcinoma of the breast were NY-BR-1 positive whereas other tumors and normal tissues were negative. Sixty percent of invasive breast carcinomas were NY-BR-1 positive, displaying cytoplasmic and/or nuclear immunoreactivity. This coexpression was verified by confocal microscopy. Although the monoclonal antibody identified intratumoral heterogeneity, a majority (72%) of NY-BR-1-positive carcinomas revealed immunoreactivity in >50% of the tumor cells. NY-BR-1 expression was more frequent in estrogen receptor-positive and lymph node-negative primary carcinomas (P < 0.05 each) and was more common in grade 1 (77%) than in grade 2 (63%) or grade 3 (50%) carcinomas (P < 0.05). This suggests that NY-BR-1 expression is lost with tumor progression. Forty-nine percent of lymph node metastases were NY-BR-1 positive.

CONCLUSION

This study supports the notion that NY-BR-1 is a differentiation antigen of the breast, which is present in normal and tumorous mammary epithelium. The organ-specific expression of NY-BR-1 and its high prevalence in metastases indicate that it could be a valuable target for cancer immunotherapy.

Expression and immunogenicity of NY-ESO-1 in hepatocellular carcinoma

BACKGROUND AND AIM

The present study was designed to investigate the expression of and humoral response against NY-ESO-1 in patients with hepatocellular carcinoma and to analyze the relationship between expression of NY-ESO-1 mRNA and clinicopathological features.

METHODS

NY-ESO-1 mRNA and protein expression in surgically resected hepatocellular carcinoma specimens, adjacent non-cancerous liver and non-tumor bearing liver were examined by reverse transcription-polymerase chain reaction and immunohistochemical staining using a monoclonal antibody against NY-ESO-1 (ES121), respectively. The antibody response to NY-ESO-1 was examined by enzyme-linked immunosorbent assay using recombinant NY-ESO-1 protein.

RESULTS

NY-ESO-1 mRNA was detected in 18 of 41 (43.9%) hepatocellular carcinomas. No NY-ESO-1 mRNA was expressed in 41 paired non-cancerous specimens and 18 specimens histologically diagnosed as liver cirrhosis or chronic hepatitis. Immunohistochemistry revealed heterogeneous expression of NY-ESO-1 protein in three of 18 NY-ESO-1 mRNA-positive hepatocellular carcinomas. None of 23 NY-ESO-1 mRNA-negative hepatocellular carcinomas expressed NY-ESO-1 protein. Antibody against NY-ESO-1 protein was detected in two of 92 patients with hepatocellular carcinoma. Both of these patients had tumors invading main branches of the portal vein.

CONCLUSIONS

The present study has demonstrated the expression of NY-ESO-1 mRNA in hepatocellular carcinoma and NY-ESO-1 antibody production in patients with advanced hepatocellular carcinoma. Although the enhancement of NY-ESO-1 protein expression and the activation of immune response of the patients with hepatocellular carcinoma are necessary, NY-ESO-1 has the potential to be a good target molecule for immunotherapy against advanced 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.

Striking Immunodominance Hierarchy of Naturally Occurring CD8+ and CD4+ T Cell Responses to Tumor Antigen NY-ESO-1

Immunodominance has been well-demonstrated in many antiviral and antibacterial systems, but much less so in the setting of immune responses against cancer. Tumor Ag-specific CD8+ T cells keep cancer cells in check via immunosurveillance and shape tumor development through immunoediting. Because most tumor Ags are self Ags, the breadth and depth of antitumor immune responses have not been well-appreciated. To design and develop antitumor vaccines, it is important to understand the immunodominance hierarchy and its underlying mechanisms, and to identify the most immunodominant tumor Ag-specific T cells. We have comprehensively analyzed spontaneous cellular immune responses of one individual and show that multiple tumor Ags are targeted by the patient's immune system, especially the "cancer-testis" tumor Ag NY-ESO-1. The pattern of anti-NY-ESO-1 T cell responses in this patient closely resembles the classical broad yet hierarchical antiviral immunity and was confirmed in a second subject.

Identification of immunoglobulin superfamily 11 (IGSF11) as a novel target for cancer immunotherapy of gastrointestinal and hepatocellular carcinomas

We previously performed gene expression profile analyses of 20 intestinal-type gastric cancers, and identified a set of genes whose expression levels were elevated in cancer tissues compared to their corresponding non-cancerous tissues. In the present study we focused on the immunoglobulin superfamily 11 gene (IGSF11). Its expression was also elevated in colorectal cancers and hepatocellular carcinomas as well as intestinal-type gastric cancers. Northern blot analysis showed that it was expressed abundantly in testis and ovary. These data suggest that IGSF11 is a good candidate of cancer-testis antigen. Furthermore, suppression of IGSF11 by siRNA retarded the growth of gastric cancer cells. To investigate the possibility of clinical application of peptide vaccine to IGSF11, we synthesized candidate epitope peptides for IGSF11 and tested whether the peptides elicit IGSF11-specific CTL. As a result, we successfully established oligo-clonal CTL by stimulation with IGSF11-9-207 (ALSSGLYQC). In addition, we also established additional CTL using IGSF11-9V (ALSSGLYQV), anchor-modified peptides of IGSF11-9-207. These peptides showed IGSF11-specific cytotoxic activity in an HLA-A*0201-restricted fashion, suggesting that these peptides may be applicable for cancer immunotherapy. These findings have provided a novel insight into carcinogenesis of the stomach, colon and liver, and will be helpful for the development of novel therapeutic strategies to a wide range of human cancers.

Differential gene expression in liposarcoma, lipoma, and adipose tissue

Malignant transformation is thought to be associated with changes in the expression of a number of genes, and this alteration in gene expression is felt to be critical to the development of the malignant phenotype. Sarcomas represent a diverse group of tumors derived from cells of mesenchymal origin. Marked heterogeneity exists in the biological behavior of sarcomas, even within histologic subtypes of sarcomas. In an effort to better understand the biology of liposarcomas, gene expression in normal adipose tissue, lipomas, and liposarcomas was examined using the Affymetrix microarray technology. Differences in gene expression were quantified as the fold change in gene expression among the sample sets. Differences in gene expression among normal adipose tissue, lipomas, and liposarcomas were observed. In addition, genes expressed uniquely in liposarcoma among these and 18 other tissue sample sets were identified. Gene sets were devised that allowed the separation of liposarcomas from other samples, and most normal adipose tissue from most lipomas using the Eisen clustering software "Cluster." We conclude that differences in gene expression can be identified among different tumors derived from the adipocyte series. Such differences in gene expression may help differentiate among subtypes of sarcomas, and may also yield clues to the pathophysiology of this heterogeneous group of tumors.

Immunization of HLA-A*0201 and/or HLA-DPbeta1*04 patients with metastatic melanoma using epitopes from the NY-ESO-1 antigen

HLA class I-restricted peptides are often used in peptide vaccine regimens. There is strong evidence that many of these peptides can generate specific CD8 T-cell responses in vivo; however, only occasional objective clinical responses have been reported. To test whether provision of "help" would enhance antitumor immunity, the authors initiated a clinical trial in which patients with metastatic melanoma were immunized against the NY-ESO-1 tumor antigen, using an HLA-A2-restricted peptide (ESO-1:165V), an HLA-DP4-restricted peptide (NY-ESO-1:161-180), or both peptides given concomitantly. The first cohorts received only ESO-1:165V, using three vaccination schedules. Immunologically, most patients developed immune responses to the HLA-A2-restricted native ESO-1 epitope after vaccination. Peptide vaccine given daily for 4 days appeared to induce immunologic responses more rapidly than if given once a week or once every 3 weeks. In contrast, vaccination using the NY-ESO-1:161-180 peptide induced immune responses in only a few patients. Clinically, one patient who received NY-ESO-1:161-180 peptide alone had a partial response lasing 12 months. Concomitant vaccination with the HLA class II-restricted peptide did not alter the immune response to the HLA class I-restricted peptide form NY-ESO-1. However, vaccination with the HLA-A2-restricted epitope generated primarily T cells that did not recognize tumor after in vitro sensitization. This result raises questions about the use of synthetic peptides derived from NY-ESO-1 as a sole form of immunization.

Expression of MHC class I, MHC class II, and cancer germline antigens in neuroblastoma

BACKGROUND

Neuroblastoma is the most common solid extracranial tumor in childhood, still with poor survival rates for metastatic disease. Neuroblastoma cells are of neuroectodermal origin and express a number of cancer germline (CG) antigens. These CG antigens may represent a potential target for immunotherapy such as peptide-based vaccination strategies.

OBJECTIVE

The purpose of this study was to analyze the presence of MAGE-A1, MAGE-A3/A6, and NY-ESO-1 on an mRNA and protein level and to determine the expression of MHC class I and MHC class II antigens within the same tumor specimens.

METHODS

A total of 68 tumors were available for RT-PCR, and 19/68 tumors were available for immunohistochemical (IHC) analysis of MAGE-A1, MAGE-A3/A6, and NY-ESO-1. In parallel, the same tumors were stained with a panel of antibodies for MHC class I and MHC class II molecules.

RESULTS

Screening of 68 tumor specimens by RT-PCR revealed expression of MAGE-A1 in 44%, MAGE-A3/A6 in 21%, and NY-ESO-1 in 28% of cases. Immunohistochemistry for CG antigens of selected tumors showed good agreement between protein and gene expression. However, staining revealed a heterogeneous expression of CG antigens. None of the selected tumors showed MHC class I or MHC class II expression.

CONCLUSIONS

mRNA expression of MAGE-A1, MAGE-A3/A6, and NY-ESO-1 is congruent with the protein expression as determined by immunohistochemistry. The heterogeneous CG-antigen expression and the lack of MHC class I and II molecules may have implications for T-cell-mediated immunotherapy in neuroblastoma.

The cancer-testis antigens CT7 (MAGE-C1) and MAGE-A3/6 are commonly expressed in multiple myeloma and correlate with plasma-cell proliferation

Multiple myeloma is a malignancy of plasma cells. Vaccine immunotherapy is among the novel therapeutic strategies under investigation for this disease. To identify myeloma-associated antigens as potential targets for vaccine immunotherapy, we surveyed a comprehensive panel of bone marrow specimens from patients with monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma for expression of cancer-testis (CT) antigens. Immunohistochemistry (IHC) demonstrated that 82% of stage-III myeloma specimens expressed the CT antigen CT7 (also known as melanoma antigen C1 [MAGE-C1]) and 70% expressed MAGE-A3/6. Messenger RNA for CT7 and MAGE-A family members was detected in 87% and 100% of stage-III samples, respectively. CT7 protein expression increased with advanced stage of disease. Higher levels of CT7 and MAGE-A3/6 proteins also correlated with elevated plasma-cell proliferation. These results show that CT7 and MAGE-A3/6 are promising myeloma-associated antigens for application in vaccine immunotherapy. Furthermore, the common expression and correlation with proliferation suggest a possible pathogenic role for these proteins in myeloma.

Expression of cancer-testis antigens in endometrial carcinomas using a tissue microarray

Cancer-testis (CT) antigens are expressed in a variety of malignant tumors, but in normal adult tissue, they are only expressed in testicular germ cells. Owing to this tumor-associated expression pattern, these antigens are of major interest as potential targets for immunotherapy and possibly for diagnostic purposes. This study was performed to analyze the expression of four CT antigens, NY-ESO-1, MAGE-A3, MAGE-A4, and CT7/MAGE-C1, in endometrial carcinoma using immunohistochemistry, and to correlate expression with histologic subtypes, grade, and expression of WT1 and p53. Formalin-fixed paraffin-embedded tissues of 130 endometrial carcinomas of the following types and grades were analyzed using a tissue microarray: 85 endometrioid carcinomas (FIGO grade 1, 39; grade 2, 11; and grade 3, 35), 18 papillary serous carcinomas, 12 clear cell carcinomas, 13 malignant mixed mullerian tumors, one mucinous adenocarcinoma, and one undifferentiated carcinoma. The following anti-CT monoclonal antibodies/antigens were studied by immunohistochemistry: monoclonal antibody ES121/NY-ESO-1, monoclonal antibody M3H67/MAGE-A3, monoclonal antibody 57B/MAGE-A4, and monoclonal antibody CT7-33/CT7. The CT expression data were compared to WT1 and p53 protein expression as analyzed in a previous study. Positive staining with anti-CT monoclonal antibodies was graded as follows: focal, <5% positive cells; 1+, 5-25% cells; 2+, 26-50% cells; 3+, 51-75%; and 4+, >75% cells. The 3+ and 4+ staining patterns were considered homogeneous patterns of potential clinical significance and were scored positive for statistical analysis. In low-grade tumors, the most immunoreactivity was seen with mAb M3H67 but little labeling was observed with the other monoclonal antibodies. In high-grade tumors, monoclonal antibodies M3H67 (25%), 57B (23%), and CT7-33 (20%) showed the highest reactivity, while ES121 showed the lowest immunoreactivity (6%). The staining pattern was mostly heterogeneous. Statistical significance was found solely for the correlation of monoclonal antibody 57B staining and p53 expression. No correlation was found for any anti-CT monoclonal antibody staining and clinical stage or for anti-CT staining and WT1 expression. CT antigens CT7, MAGE-A3 and MAGE-A4, but not NY-ESO-1, are expressed in high-grade endometrial carcinomas, and expression of MAGE-A4 is correlated with the presence of overexpressed p53.

Immunohistochemical and Molecular Analysis of Human Melanomas for Expression of the Human Cancer-Testis Antigens NY-ESO-1 and LAGE-1

PURPOSE

NY-ESO-1 and LAGE-1 are homologous cancer-testis antigens, which are expressed in many different cancers. It is essential to type tumors accurately to assess patient suitability for clinical trials which target these. This study evaluates typing strategies used to distinguish these two homologous but distinct antigens and to characterize and quantitate expression of each in clinical samples.

EXPERIMENTAL DESIGN

We typed 120 malignant melanomas for the expression of NY-ESO-1 and LAGE-1 with immunohistochemistry, reverse transcription-PCR (RT-PCR), and quantitative real-time (qRT-PCR), which was also used to explore the relationship between NY-ESO-1 and LAGE expression.

RESULTS

The two monoclonal antibodies ES121 and E978 had very similar immunohistochemistry reactivities. Both were specific for NY-ESO-1 because neither bound to homologous LAGE-1 peptides despite 84% overall amino acid homology. Of 120 melanomas tested by immunohistochemistry, NY-ESO-1 was expressed in >50% of cells in 23 melanomas (19%), between 11 and 50% cells in 15 (12.5%), <11% cells in 16 (13.5%), and negative in 66 (55%). Although specific for both antigens, the PCR methods did not provide this information about microheterogeneity. Polymorphisms in the LAGE-1 gene resulted in false negative LAGE-1 typing by qRT-PCR by inhibiting binding of oligonucleotide primers, thereby showing the exquisite specificity of qRT-PCR as a typing method.

CONCLUSIONS

For NY-ESO-1 typing, immunohistochemistry compared favorably with the RT-PCR, with the added advantage of being able to characterize heterogeneity of antigen expression. Because neither mAb bound LAGE and because there was no coordinate expression LAGE and NY-ESO-1, separate typing for each is required.

Melanoma or not? Cancer testis antigens may help

BACKGROUND

Cancer testis antigens (CTAs) are expressed in a variety of malignant tumours. No CTA expression is found in normal adult tissues, except in male germ cells and occasionally placenta. To date, more than 20 CTAs or antigen families have been identified.

OBJECTIVES

Owing to their tumour-associated expression pattern, CTAs may be useful for making a distinction between benign and malignant neoplasms. The present study was done to analyse the value of CTAs for the discrimination of cutaneous melanoma and naevi.

PATIENTS AND METHODS

Primary melanomas (38) and 19 naevi were analysed for their expression of CTAs by immunohistochemistry using the following monoclonal antibodies (mAb) to the following antigens (mAb/antigen): MA454/MAGE-A1, 57B/MAGE-A4, ES121/NY-ESO-1. In a subset of melanomas (n = 26), the CTA panel was extended to three additional CTAs (mAb/antigen): CT7-33/MAGE-C1, M3H67/MAGE-A3 and GAGE/GAGE.

RESULTS

All 19 naevi were negative for the mAbs MA454, M3H67, 57B, ES121, CT7-33 and GAGE. In melanoma, the immunoreactivity was as follows: MA454: 8/38 (21%), 57B 11/38 (29%), ES121 9/38 (24%). However, 19/38 (50%) were positive for at least one CTA. When 26 melanomas were tested for the expression of six different CTAs 20/26 (77%) were positive for at least one CTA.

CONCLUSIONS

CTAs may be useful in the determination of suspected malignancy in cutaneous melanomas. The low incidence of particular CTAs can be overcome by increasing the number of CTAs analysed.

Identification of HLA-A24-restricted CTL epitope from cancer-testis antigen, NY-ESO-1, and induction of a specific antitumor immune response

PURPOSE

For the development of peptide-based, cancer-specific immunotherapy, the identification of CTL epitopes from additional tumor antigens is very important. NY-ESO-1, a cancer-testis antigen, is considered to be a promising target of tumor-specific immunotherapy. Because HLA-A24-expressing individuals cover >60% in the population of Japan, we aim at identifying NY-ESO-1-encoded peptide presented by HLA-A24.

EXPERIMENTAL DESIGN

In our study, a HLA-A24-restricted CTL epitope was identified by using the following four-step procedure: (a) computer-based epitope prediction from the amino acid sequence of NY-ESO-1 antigen; (b) peptide-binding assay to determine the affinity of the predicted peptide with HLA-A24 molecule; (c) stimulation of primary T-cell response against the predicted peptides in vitro; and (d) testing of the induced CTLs toward various carcinoma cells expressing NY-ESO-1 antigen and HLA-A24.

RESULTS

Of the tested peptides, effectors induced by a peptide of NY-ESO-1 at residue position 158-166 lysed three kinds of carcinoma cells expressing both NY-ESO-1 and HLA-A24. Our results indicate that peptide NY-ESO-1 (158-166) (LLMWITQCF) is a new HLA-A24-restricted CTL epitope capable of inducing NY-ESO-1-specific CTLs in vitro mediating HLA class I-restricted manner.

CONCLUSIONS

We identified a novel HLA-A24-restricted NY-ESO-1-derived epitope peptide (LLMWITQCF) that could induce specific CTLs from the peripheral blood mononuclear cells of HLA-A24(+) healthy donors. This peptide would be useful in further evaluating the clinical utility of peptide-based, cancer-specific immunotherapy against various histological tumors.

NY-ESO-1 expression and its serum immunoreactivity in esophageal cancer

PURPOSE

NY-ESO-1, a member of the cancer/testis antigen (CTA) family, elicits humoral and cellular immune responses in patients with advanced cancer. Unresectable or metastatic esophageal carcinoma patients do not benefit from the present multimodality treatment regimens in terms of survival. The objectives of this study were to analyze the antibody response to NY-ESO-1 antigen in patients with esophageal cancer and to determine the potential of NY-ESO-1 for use in tumor-specific immunotherapy.

METHODS

Serum from 69 patients with esophageal cancer was investigated for antibody production against NY-ESO-1 by Western blot analysis. Also analyzed by immunohistochemistry were 56 tissue samples from these patients for NY-ESO-1 protein expression.

RESULTS

NY-ESO-1 protein expression was found in 18 of 56 (32%) esophageal carcinomas. Serum immunoreactivity specific for NY-ESO-1 was found in 9 patients (13%) of whom 8 were in the advanced stage (stages III and IV). There was no relationship between clinicopathologic features and serum immunoreactivity for NY-ESO-1. NY-ESO-1 protein expression was detected in three of five antibody-positive patients whose tissue was available for analysis. Survival analysis showed no significant difference between antibody-positive and antibody-negative patient groups.

CONCLUSIONS

A humoral immune response to NY-ESO-1 antigen was established in patients with advanced esophageal cancer. NY-ESO-1 is a good candidate for vaccine-based immunotherapy for advanced esophageal carcinoma.

Immunity against soft-tissue sarcomas

Recent advances in basic medical sciences have led to a deeper understanding of the molecular characteristics of soft-tissue sarcomas. Likewise, novel technologies have led to a better appreciation of the relationship between an antigenic stimulus and the subsequent immune response against the antigen. In the past few years, the intersection of the understanding of the immune system and the knowledge of sarcoma biology has become apparent. As seen with other forms of cancer, there is a detectable autologous immune response against sarcomas. It is the hope of many investigators that the hints of a tumor-specific immune response will be enough to generate a signal that can be amplified and directed against the host sarcoma. The data regarding the initial evidence of immune responses against sarcomas are reviewed in the context of current or potential clinical studies.

Immunomic analysis of human sarcoma

The screening of cDNA expression libraries from human tumors with serum antibody (SEREX) has proven to be a powerful method for identifying the repertoire of tumor antigens recognized by the immune system of cancer patients, referred to as the cancer immunome. In this regard, cancer/testis (CT) antigens are of particular interest because of their immunogenicity and restricted expression patterns. Synoivial sarcomas are striking with regard to CT antigen expression, with >80% of specimens homogeneously expressing NY-ESO-1 and MAGE-A3. In the present study, 54 sarcoma patients were tested for serum antibodies to NY-ESO-1, SSX2, MAGE-A1, MAGE-A3, MAGE-A4, MAGE-A10, CT7, and CT10. Two patients had detectable antibodies to CT antigens, and this seroreactivity was restricted to NY-ESO-1. Thus, although highly expressed in sarcoma, CT antigens do not induce frequent humoral immune responses in sarcoma patients. Sera from these two patients were used to immunoscreen cDNA libraries from two synovial sarcoma cell lines and normal testis, resulting in the identification of 113 distinct antigens. Thirty-nine antigens were previously identified by SEREX analysis of other tumor types, and 2339 antigens (59%) had a serological profile that was not restricted to cancer patients, indicating that only a proportion of SEREX-defined antigens are cancer-related. A novel CT antigen, NY-SAR-35, mapping to chromosome Xq28 was identified among the cancer-related antigens, and encodes a putative extracellular protein. In addition to testis-restricted expression, NY-SAR-35 mRNA was expressed in sarcoma, melanoma, esophageal cancer, lung cancer and breast cancer. NY-SAR-35 is therefore a potential target for cancer vaccines and monoclonal antibody-based immunotherapies.

Cancer/testis tumour-associated antigens: immunohistochemical detection with monoclonal antibodies

Cancer/testis tumour-associated antigens (C/T TAA) were the first human tumour-associated antigens to be characterised at the molecular level. Specific genes are expressed in the testis and in tumours of varying histological origin. The tissue expression pattern supports the notion that these antigens could be targets for active specific immunotherapy. Specific serological reagents have been developed and have helped to clarify biochemical characteristics of C/T TAA and to assess their distribution within clinical tumour samples. We review immunohistochemical evidence of the expression of C/T TAA known to be recognised by specific cytotoxic T lymphocytes. The emerging picture is consistent with a mostly heterogeneous expression in human cancers. These findings support the concept of multiantigenic tumour vaccine preparations. Moreover, the wide range of tumours in which C/T TAA have been detected urges further efforts to develop effective specific immunotherapeutic procedures.