Cancer testis antigen expression in gastrointestinal stromal tumors: new markers for early recurrence

Advances in immunology and immunotherapy for mesenchymal gastrointestinal cancers

Mesenchymal gastrointestinal cancers are represented by the gastrointestinal stromal tumors (GISTs) which occur throughout the whole gastrointestinal tract, and affect human health and economy globally. Curative surgical resections and tyrosine kinase inhibitors (TKIs) are the main managements for localized GISTs and recurrent/metastatic GISTs, respectively. Despite multi-lines of TKIs treatments prolonged the survival time of recurrent/metastatic GISTs by delaying the relapse and metastasis of the tumor, drug resistance developed quickly and inevitably, and became the huge obstacle for stopping disease progression. Immunotherapy, which is typically represented by immune checkpoint inhibitors (ICIs), has achieved great success in several solid tumors by reactivating the host immune system, and been proposed as an alternative choice for GIST treatment. Substantial efforts have been devoted to the research of immunology and immunotherapy for GIST, and great achievements have been made. Generally, the intratumoral immune cell level and the immune-related gene expressions are influenced by metastasis status, anatomical locations, driver gene mutations of the tumor, and modulated by imatinib therapy. Systemic inflammatory biomarkers are regarded as prognostic indicators of GIST and closely associated with its clinicopathological features. The efficacy of immunotherapy strategies for GIST has been widely explored in pre-clinical cell and mouse models and clinical experiments in human, and some patients did benefit from ICIs. This review comprehensively summarizes the up-to-date advancements of immunology, immunotherapy and research models for GIST, and provides new insights and perspectives for future studies.

Beyond the Driver Mutation: Immunotherapies in Gastrointestinal Stromal Tumors

Gastrointestinal stromal tumors (GISTs) are a subtype of soft tissue sarcoma (STS), and have become a concept of oncogenic addiction and targeted therapies.The large majority of these tumors develop after a mutation in KIT or platelet derived growth factor receptor α (PDGFRα), resulting in uncontrolled proliferation. GISTs are highly sensitive to imatinib. GISTs are immune infiltrated tumors with a predominance of tumor-associated macrophages (TAMs) and T-cells, including many CD8+ T-cells, whose numbers are prognostic. The genomic expression profile is that of an inhibited Th1 response and the presence of tertiary lymphoid structures and B cell signatures, which are known as predictive to response to ICI. However, the microtumoral environment has immunosuppressive attributes, with immunosuppressive M2 macrophages, overexpression of indoleamine 2,3-dioxygenase (IDO) or PD-L1, and loss of major histocompatibility complex type 1. In addition to inhibiting the KIT oncogene, imatinib appears to act by promoting cytotoxic T-cell activity, interacting with natural killer cells, and inhibiting the expression of PD-L1. Paradoxically, imatinib also appears to induce M2 polarization of macrophages. There have been few immunotherapy trials with anti-CTLA-4 or anti-PD-L1drugs and available clinical data are not very promising. Based on this comprehensive analysis of TME, we believe three immunotherapeutic strategies must be underlined in GIST. First, patients included in clinical trials must be better selected, based on the identified driver mutation (such as PDGFRα D842V mutation), the presence of tertiary lymphoid structures (TLS) or PD-L1 expression. Moreover, innovative immunotherapeutic agents also provide great interest in GIST, and there is a strong rationale for exploring IDO targeting after disease progression during imatinib therapy. Finally and most importantly, there is a strong rationale to combine of c-kit inhibition with immune checkpoint inhibitors.

MAGE expression in head and neck squamous cell carcinoma primary tumors, lymph node metastases and respective recurrences-implications for immunotherapy

Melanoma associated antigens (MAGE) are potential targets for immunotherapy and have been associated with poor overall survival (OS) in head and neck squamous cell carcinoma (HNSCC). However, little is known about MAGE in lymph node metastases (LNM) and recurrent disease (RD) of HNSCC.To assess whether MAGE expression increases with metastasis or recurrence, a tissue microarray (TMA) of 552 primary tumors (PT), 219 LNM and 75 RD was evaluated by immunohistochemistry for MAGE antigens using three monoclonal antibodies to multiple MAGE family members. Mean expression intensity (MEI) was obtained from triplicates of each tumor specimen.The median MEI compared between PT, LNM and RD was significantly higher in LNM and RD. In paired samples, MEI was comparable in PT to respective LNM, but significantly different from RD. Up to 25% of patients were negative for pan-MAGE or MAGE-A3/A4 in PT, but positive in RD. The prognostic impact of MAGE expression was validated in the TMA cohort and also in TCGA data (mRNA). OS was significantly lower for patients expressing pan-MAGE or MAGE-A3/A4 in both independent cohorts.MAGE expression was confirmed as a prognostic marker in HNSCC and may be important for immunotherapeutic strategies as a shared antigen.

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.

Expression of immune checkpoint molecules of T cell immunoglobulin and mucin protein 3/galectin-9 for NK cell suppression in human gastrointestinal stromal tumors

Monoclonal antibody therapy for immune checkpoint blockade has achieved promising results for several types of malignant tumors. For the future treatment of gastrointestinal stromal tumors (GISTs) by immune checkpoint blockade, expression of immune checkpoint-related molecules that suppress antitumor immunity in GISTs was examined. Infiltration of immune cell types into 19 GIST tissues was analyzed by immunohistochemistry, and expression of T cell immunoglobulin and mucin protein 3 (Tim-3) and programmed cell death-1 (PD-1) in the infiltrated immune cells was examined by immunofluorescence microscopy. The expression status of galectin-9 in the GIST tumor cells was also determined by immunohistochemistry. All the GIST tissues showed CD8+ T cell infiltration and 8 showed CD56+ natural killer (NK) cell infiltration, and the numbers of infiltrated CD8+ T and NK cells were strongly correlated. However, these CD8+ T and NK cells were CD69-negative inactivated cells. Tim-3 was expressed in the infiltrated NK cells in 6/8 (75%) of the GIST tissues. Expression of galectin-9, a ligand of Tim-3, was observed in 13/19 (68.4%) GIST tissues and all of the GIST tissues with Tim-3+ NK cell infiltration showed positive galectin-9 expression. No PD-1 expression in the infiltrated NK cells and neither Tim-3 nor PD-1 expression was observed in the infiltrated CD8+ T cells. Interaction between Tim-3 in infiltrated NK cells and galectin-9 in tumor cells may be involved in an immune checkpoint mechanism for suppression of antitumor immunity in GISTs. Blockade of the Tim-3/galectin-9 pathway may become a new strategy for GIST treatment.

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.

Expression of cancer-testis antigens MAGEA1, MAGEA3, ACRBP, PRAME, SSX2, and CTAG2 in myxoid and round cell liposarcoma

Myxoid and round-cell liposarcoma is a frequently encountered liposarcoma subtype. The mainstay of treatment remains surgical excision with or without chemoradiation. However, treatment options are limited in the setting of metastatic disease. Cancer-testis antigens are immunogenic antigens with the expression largely restricted to testicular germ cells and various malignancies, making them attractive targets for cancer immunotherapy. Gene expression studies have reported the expression of various cancer-testis antigens in liposarcoma, with mRNA expression of CTAG1B, CTAG2, MAGEA9, and PRAME described specifically in myxoid and round-cell liposarcoma. Herein, we further explore the expression of the cancer-testis antigens MAGEA1, ACRBP, PRAME, and SSX2 in myxoid and round-cell liposarcoma by immunohistochemistry in addition to determining mRNA levels of CTAG2 (LAGE-1), PRAME, and MAGEA3 by quantitative real-time PCR. Samples in formalin-fixed paraffin-embedded blocks (n=37) and frozen tissue (n=8) were obtained for immunohistochemistry and quantitative real-time PCR, respectively. Full sections were stained with antibodies to MAGEA1, ACRBP, PRAME, and SSX2 and staining was assessed for intensity (1-2+) and percent tumor positivity. The gene expression levels of CTAG2, PRAME, and MAGEA3 were measured by quantitative real-time PCR. In total, 37/37 (100%) of the samples showed predominantly strong, homogenous immunoreactivity for PRAME. There was a variable, focal expression of MAGEA1 (11%) and SSX2 (16%) and no expression of ACRBP. Quantitative real-time PCR demonstrated PRAME and CTAG2 transcripts in all eight samples: six tumors with high mRNA levels; two tumors with low mRNA levels. The gene expression of MAGEA3 was not detected in the majority of cases. In conclusion, myxoid and round-cell liposarcomas consistently express PRAME by immunohistochemistry as well as CTAG2 and PRAME by qualitative real-time PCR. This supports the use of cancer-testis antigen-targeted immunotherapy in the treatment of this malignancy.

Simultaneous cytoplasmic and nuclear protein expression of melanoma antigen-A family and NY-ESO-1 cancer-testis antigens represents an independent marker for poor survival in head and neck cancer

The prognosis of head and neck squamous cell carcinoma (HNSCC) patients remains poor. The identification of high-risk subgroups is needed for the development of custom-tailored therapies. The expression of cancer-testis antigens (CTAs) has been linked to a worse prognosis in other cancer types; however, their prognostic value in HNSCC is unclear because only few patients have been examined and data on CTA protein expression are sparse. A tissue microarray consisting of tumor samples from 453 HNSCC patients was evaluated for the expression of CTA proteins using immunohistochemistry. Frequency of expression and the subcellular expression pattern (nuclear, cytoplasmic, or both) was recorded. Protein expression of melanoma antigen (MAGE)-A family CTA, MAGE-C family CTA and NY-ESO-1 was found in approximately 30, 7 and 4% of tumors, respectively. The subcellular expression pattern in particular had a marked impact on the patients' prognosis. Median overall survival (OS) of patients with (i) simultaneous cytoplasmic and nuclear expression compared to (ii) either cytoplasmic or nuclear expression and (iii) negative patients was 23.0 versus 109.0 versus 102.5 months, for pan-MAGE (p < 0.0001), 46.6 versus 50.0 versus 109.0 for MAGE-A3/A4 (p = 0.0074) and 13.3 versus 50.0 versus 100.2 months for NY-ESO-1 (p = 0.0019). By multivariate analysis, these factors were confirmed as independent markers for poor survival. HNSCC patients showing protein expression of MAGE-A family members or NY-ESO-1 represent a subgroup with an extraordinarily poor survival. The development of immunotherapeutic strategies targeting these CTA may, therefore, be a promising approach to improve the outcome of HNSCC patients.

The clinical value of the quantitative detection of four cancer-testis antigen genes in multiple myeloma

BACKGROUND

Cancer-testis (CT) antigen genes might promote the progression of multiple myeloma (MM). CT antigens may act as diagnostic and prognostic markers in MM, but their expression levels and clinical implications in this disease are not fully understood. This study measured the expression levels of four CT antigen genes in Chinese patients with MM and explored their clinical implications.

METHODS

Real-time quantitative polymerase chain reaction (qPCR) was used to quantify the expression of MAGE-C1/CT7, MAGE-A3, MAGE-C2/CT10 and SSX-2 mRNA in 256 bone marrow samples from 144 MM patients.

RESULTS

In the newly diagnosed patients, the positive expression rates were 88.5% for MAGE-C1/CT7, 82.1% for MAGE-C2/CT10, 76.9% for MAGE-A3 and 25.6% for SSX-2. The expression levels and the number of co-expressed CT antigens correlated significantly with several clinical indicators, including the percentage of plasma cells infiltrating the bone marrow, abnormal chromosome karyotypes and the clinical course.

CONCLUSION

MAGE-C1/CT7, MAGE-A3, MAGE-C2/CT10 and SSX-2 expression levels provide potentially effective clinical indicators for the auxiliary diagnosis and monitoring of treatment efficacy in MM.

Proteomic approach toward personalized sarcoma treatment: lessons from prognostic biomarker discovery in gastrointestinal stromal tumor

Sarcomas range from curable tumors to those causing death via metastasis and recurrence. Thus, there is an urgent need for biomarker identification in order to assess the degree of malignancy, predict prognosis, and evaluate possible therapies. Various proteomic approaches and different clinical materials have been used to this end, and candidate biomarkers have been reported for the different types of sarcomas. However, the sample size used in these biomarker studies was generally insufficient, and thus far, no biomarker has been proved useful in clinics. Given that sarcomas are rare, biomarker validation in this setting is more challenging than in other malignancies. In gastrointestinal stromal tumor, adjuvant therapy has proven to be effective. However, only 40% patients experience metastasis after curative surgery alone, and the rest of the patients may not need adjuvant therapy. Using a proteomic approach, we identified pfetin (potassium channel tetramerization domain containing 12, KCTD 12) as a novel prognostic biomarker for sarcoma, and immunohistochemically confirmed its clinical usefulness by a multiinstitutional validation study. Here, we describe our experience and discuss the critical points in the discovery of this biomarker.

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.

Cancer testis antigens and NY-BR-1 expression in primary breast cancer: prognostic and therapeutic implications

BACKGROUND

Cancer-testis antigens (CTA) comprise a family of proteins, which are physiologically expressed in adult human tissues solely in testicular germ cells and occasionally placenta. However, CTA expression has been reported in various malignancies. CTAs have been identified by their ability to elicit autologous cellular and or serological immune responses, and are considered potential targets for cancer immunotherapy. The breast differentiation antigen NY-BR-1, expressed specifically in normal and malignant breast tissue, has also immunogenic properties. Here we evaluated the expression patterns of CTAs and NY-BR-1 in breast cancer in correlation to clinico-pathological parameters in order to determine their possible impact as prognostic factors.

METHODS

The reactivity pattern of various mAbs (6C1, MA454, M3H67, 57B, E978, GAGE #26 and NY-BR-1 #5) were assessed by immunohistochemistry in a tissue micro array series of 210 randomly selected primary invasive breast cancers in order to study the diversity of different CTAs (e.g. MAGE-A, NY-ESO-1, GAGE) and NY-BR-1. These expression data were correlated to clinico-pathological parameters and outcome data including disease-free and overall survival.

RESULTS

Expression of at least one CTA was detectable in the cytoplasm of tumor cells in 37.2% of the cases. NY-BR-1 expression was found in 46.6% of tumors, respectively. Overall, CTA expression seemed to be linked to adverse prognosis and M3H67 immunoreactivity specifically was significantly correlated to shorter overall and disease-free survival (p=0.000 and 0.024, respectively).

CONCLUSIONS

Our findings suggest that M3H67 immunoreactivity could serve as potential prognostic marker in primary breast cancer patients. The exclusive expression of CTAs in tumor tissues as well as the frequent expression of NY-BR-1 could define new targets for specific breast cancer therapies.

Cancer/testis antigens expression and autologous serological response in a set of Brazilian non-Hodgkin's lymphoma patients

BACKGROUND

Based on their tumor-associated expression pattern, cancer/testis antigens (CTAs) are considered potential targets for cancer immunotherapy. We aim to evaluate the expression of CTAs in non-Hodgkin's lymphoma (NHL) samples and the ability of these patients to elicit spontaneous humoral immune response against CTAs.

METHODS

Expression of MAGE-A family, CT7/MAGE-C1, CT10/MAGE-C2, GAGE and NY-ESO-1 was analyzed by immunohistochemistry in a tissue microarray generated from 106 NHL archival cases. The humoral response against 19 CTAs was tested in 97 untreated NHL serum samples using ELISA technique.

RESULTS

11.3 % of NHL tumor samples expressed at least 1 CTA. MAGE-A family (6.6 %), GAGE (5.7 %) and NY-ESO-1(4.7 %) were the most frequently expressed antigens. We found no statistically significant correlation between CTA positivity and clinical parameters such as NHL histological subtype, Ann Arbor stage, international prognostic index score, response to treatment and overall survival. Humoral response against at least 1 CTA was observed in 16.5 % of NHL serum samples. However, overall seroreactivity was low, and strong titers (>1:1000) were observed in only two diffuse large B-cell lymphomas patients against CT45.

CONCLUSION

Our findings are in agreement with most of published studies in this field to date and suggest an overall low expression of CTAs in NHL patients. However, as many new CTAs have been described recently and some of them are found to be highly expressed in NHL cell lines and tumor samples, further studies exploring the expression of different panels of CTAs are needed to evaluate their role as candidates for immunotherapy in NHL patients.

Blood neutrophil-to-lymphocyte ratio is prognostic in gastrointestinal stromal tumor

BACKGROUND

The immune system has been shown to play an important role in gastrointestinal stromal tumor (GIST). The neutrophil-to-lymphocyte ratio (NLR) in blood is an easily assessable parameter of systemic inflammatory response. The aim of this study was to determine whether the NLR is prognostic in GIST.

METHODS

A total of 339 previously untreated patients with primary, localized GIST operated at our institution between 1995 and 2010 were identified from a prospectively collected sarcoma database. NLR was assessed preoperatively. Patients who received adjuvant imatinib treatment were excluded from the analysis (n = 64). Cox regression models were calculated and correlation analyses were performed.

RESULTS

On univariate analysis, NLR was associated with recurrence-free survival (RFS) (P = 0.003, hazard ratio 3.3, 95 % confidence interval 1.5-7.4). Patients with a low NLR had a 1- and 5-year RFS of 98 and 91 %, compared with 89 and 76 % in those with a high NLR. The median RFS was not reached. Positive correlations were found between NLR and mitotic rate (Pearson correlation coefficient [r] = 0.15, P = 0.03), and NLR and tumor size (r = 0.36, P = 0.0001). RFS in patients with a GIST >5 cm with low NLR was significantly longer compared to patients with high NLR (P = 0.002). Flow cytometry analysis of freshly obtained GISTs revealed that neutrophils constituted a minimal percentage of intratumoral immune cells.

CONCLUSIONS

NLR is a surrogate for high-risk tumor features. Elevated blood NLR appears to represent systemic inflammation in patients with high-risk GIST.

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 expression in hepatocellular carcinoma: A potential new marker for early recurrence after surgery

NY-ESO-1 belongs to the cancer testis antigens (CTA) family, and is identified in a variety of tumors. Certain studies have demonstrated that NY-ESO-1 predicts tumor recurrence and treatment response. No reports are currently available regarding the correlation between NY-ESO-1 and the recurrence of hepatocellular carcinoma (HCC) following surgery. The purpose of the present study was to evaluate the association between NY-ESO-1 and relapse of HCC and to explore the possible mechanisms for this correlation. A total of 120 HCC patients were analyzed for the expression of NY-ESO-1 by immunohistochemistry (IHC). A stable NY-ESO-1 over-expressed HepG2 cell line (ESO-HepG2) was established to determine the biological effects of NY-ESO-1 on cell proliferation, cell cycle and migration by using the xCELLigence DP system, flow cytometry and xCELLigence SP system. NY-ESO-1 was positive in 28 of 120 (23.3%) HCC tumor tissues. NY-ESO-1 was not detectable in adjacent normal liver tissues. A close correlation was found between NY-ESO-1 expression and the recurrence of HCC following surgery (P=0.007). Kaplan-Meier analysis showed a shorter recurrence-free survival (RFS) for patients positive for NY-ESO-1 (log-rank test, P=0.003). The Cox regression model demonstrated that NY-ESO-1 expression was a significant independent predictor for the recurrence of HCC following curative surgery (P=0.022). Compared with HepG2 cells, ESO-HepG2 cells have increased migration but not proliferation ability. In conclusion, NY-ESO-1 expression is associated with worse HCC outcome following surgery, and the mechanism for this finding may be that NY-ESO-1 increases tumor cell migration.

An overview of cancer/testis antigens expression in classical Hodgkin's lymphoma (cHL) identifies MAGE-A family and MAGE-C1 as the most frequently expressed antigens in a set of Brazilian cHL patients

ABSTRACT: BACKGROUND: Cancer/testis antigens are considered potential targets for immunotherapy due to their tumor-associated expression pattern. Although recent studies have demonstrated high expression of CT45 in classical Hodgkin's lymphomas (cHL), less is known about the expression pattern of other families of CTAs in cHL. We aim to evaluate the expression of MAGE-A family, MAGE-C1/CT7, MAGE-C2/CT10, NY-ESO1 and GAGE family in cHL and to correlate their expression with clinical and prognostic factors in cHL. METHODS: Tissue microarray was generated from 38 cHL archival cases from Pathology Department of Universidade Federal de Sao Paulo. Immunohistochemistry (IHC) was done using the following panel of antibodies: MAGE-A family (MA454, M3H67, 57B and 6C1), GAGE (#26), NY-ESO-1 (E978), MAGE-C1/CT7 (CT7-33) and MAGE-C2/CT10 (CT10#5). RESULTS: We found CTA expression in 21.1% of our cHL series. Among the tested CTAs, only MAGE-A family 7/38 (18.4%) and MAGE-C1/CT7 5/38 (13.2%) were positive in our cHL samples. We found higher CTA positivity in advanced stage (28.6%) compared to early stage (11.8%) disease, but this difference was not statistically significant. Analysis of other clinicopathological subgroups of cHL including histological subtypes, EBV status and response to treatment also did not demonstrate statistical significant differences in CTA expression. CONCLUSION: We found CTA expression in 21.1% of cHL samples using our panel. Our preliminary findings suggest that from all CTAs included in this study, MAGE-A family and MAGE-C1/CT7 are the most interesting ones to be explored in further studies.

Imatinib potentiates antitumor T cell responses in gastrointestinal stromal tumor through the inhibition of Ido

Imatinib mesylate targets mutated KIT oncoproteins in gastrointestinal stromal tumor (GIST) and produces a clinical response in 80% of patients. The mechanism is believed to depend predominantly on the inhibition of KIT-driven signals for tumor-cell survival and proliferation. Using a mouse model of spontaneous GIST, we found that the immune system contributes substantially to the antitumor effects of imatinib. Imatinib therapy activated CD8(+) T cells and induced regulatory T cell (T(reg) cell) apoptosis within the tumor by reducing tumor-cell expression of the immunosuppressive enzyme indoleamine 2,3-dioxygenase (Ido). Concurrent immunotherapy augmented the efficacy of imatinib in mouse GIST. In freshly obtained human GIST specimens, the T cell profile correlated with imatinib sensitivity and IDO expression. Thus, T cells are crucial to the antitumor effects of imatinib in GIST, and concomitant immunotherapy may further improve outcomes in human cancers treated with targeted agents.

Protein expression of cancer testis antigens predicts tumor recurrence and treatment response to imatinib in gastrointestinal stromal tumors

Cancer testis antigens (CTAs) have been identified in various tumors as immunological tumor targets. In gastrointestinal stromal tumor (GIST), the prediction of malignant potential remains difficult but is crucial in the era of adjuvant imatinib treatment. Here, we analyzed the impact of CTAs on tumor recurrence and its role on the treatment response to imatinib. The expression of the most frequent CTAs MAGE-A1, MAGE-A3, MAGE-A4, MAGE-C1 and NY-ESO-1 was analyzed by immunohistochemistry. The duration between the initial operation and the tumor relapse was defined as recurrence free survival (RFS). All recurrent cases were treated with imatinib. The tumor response to imatinib was graded according to the modified CT response evaluation criteria. Patients with a CTA positive GIST (n = 23, 27%) had a significantly shorter RFS (p = 0.001) compared to negative cases (n = 63, 73%). The median RFS was 25 months in CTA positive patients and was not reached during the study period in CTA negative patients. According to the established staging criteria CTA positive tumors were predominantly high-risk tumors (p = 0.001). The expression of MAGE-A3 (p = 0.018) and NY-ESO-1 (p = 0.001) were associated with tumor progression under imatinib treatment. A tendency for worse tumor response to imatinib was observed in CTA positive tumors (p = 0.056). Our study confirms the expression of CTAs in GIST and their role as prognostic markers. It also draws attention to the potential impact of CTAs on the tumor response to imatinib.

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.

Cancer-testis antigen expression in primary cutaneous melanoma has independent prognostic value comparable to that of Breslow thickness, ulceration and mitotic rate

To determine the effect of Cancer-Testis Antigen (CTAg) expression on the natural history of primary cutaneous melanoma we compared its impact on prognosis with that of known prognostic factors and its relationship with other clinicopathologic characteristics. The immunohistochemical expression of three CTAgs (MAGE-A1, MAGE-A4 and NY-ESO-1) in 348 cases of stage I and stage II primary cutaneous melanoma was analysed and correlated with clinicopathologic characteristics, relapse free survival (RFS) and overall survival (OS). A Cox proportional hazards regression model was used to analyse factors which independently predicted RFS. All three CTAgs were significantly co-expressed with each other (p < 0.001). The median RFS for patients with CTAg-negative tumours and CTAg-positive tumours was 72 months and 45 months, respectively, (P = 0.008). Univariate analysis demonstrated that the impact of CTAg expression on RFS was comparable in magnitude to that of Breslow thickness, ulceration and tumour mitotic rate. Multivariate Cox regression analysis indicated that CTAg expression was a powerful independent predictor of RFS (risk ratio (RR) = 1.715, 95% confidence interval (CI) = 0.430-0.902, P = 0.010). In contrast, CTAg expression was demonstrated to have no prognostic impact on overall survival. This study demonstrates that CTAg expression in primary cutaneous melanoma is a strong independent predictor of RFS and it is comparable to other known important prognostic factors. CTAg expression has no relationship with overall survival, suggesting anti-melanoma immunity directed towards CTAg expression may contribute to the natural history of the disease. In view of these results, further investigation of the function of CTAgs and their potential use in therapeutic targeting is warranted.

Clinical implications of expression of MAGE-1 and NY-ESO-1 mRNAs in gastrointestinal stromal tumors

AIM: To evaluate the possibility of using melanoma antigen-1 (MAGE-1) and New York-esophageal-1 (NY-ESO-1) antigens as specific targets for immunotherapy of gastrointestinal stromal tumors (GISTs) and using MAGE-1 and NY-ESO-1 mRNA levels as auxiliary parameters for risk classification of GISTs.

METHODS: The expression of MAGE-1 and NY-ESO-1 mRNAs was detected by reverse transcription-polymerase chain reaction (RT-PCR) in 30 GIST tissue specimens. The correlation of MAGE-1 and NY-ESO-1 mRNA expression with pathological parameters was analyzed in GISTs.

RESULTS: The positive rates of MAGE-1 and NY-ESO-1 mRNA expression in GIST specimens were 30% and 47%, respectively. At least one of these two cancer-testis antigens (CTAs) was detected in 18 GIST tissue specimens. The expression of MAGE-1 and NY-ESO-1 mRNAs was not correlated with age, sex or pathologic type (P > 0.05), but correlated with tumor site, tumor diameter and risk grade (all P < 0.05). The expression levels of MAGE-1 and NY-ESO-1 mRNAs in GISTs of high risk grade were significantly higher than those in GISTs of low risk grade (P < 0.05). No negative correlation was noted between the expression of MAGE-1 and NY-ESO-1 mRNAs in GISTs (r = 0.018, P > 0.05).

CONCLUSION: MAGE-1 and NY-ESO-1 mRNAs are expressed specifically in GIST tissue and may be potentially promising targets for antigen-specific immunotherapy of GISTs. The expression of MAGE-1 and NY-ESO-1 mRNAs is correlated with the risk grade of GISTs. MAGE-1 and NY-ESO-1 mRNA levels are promising auxiliary parameters for risk classification of GISTs.