Human Leukocyte Antigen-A Allele Distribution in Nasopharyngeal Carcinoma Patients Showing Anti-Melanoma-Associated Antigen A or Synovial Sarcoma X-2 T Cell Response in Blood

Background： Development of innovative immunotherapy is imperative to improve the poor survival of the nasopharyngeal carcinoma （NPC） patients. In this study, we evaluated the T cell response to melanoma-associated antigen （MAGE）-A1, MAGE-A3, or synovial sarcoma X-2 （SSX-2） in the peripheral blood of treatment-naive NPC patients. The relationship of responses among the three proteins and the human leukocyte antigen （HLA）-A types were analyzed to provide evidence of designing novel therapy. Methods： Sixty-one NPC patients admitted into the Tumor Hospital affiliated to the Xinjiang Medical University between March 2015 and July 2016 were enrolled. Mononuclear cells were isolated from the peripheral blood before any treatment. HLA-A alleles were typed with Sanger sequence-based typing technique. The T cell response to the MAGE-A1, MAGE-A3, or SSX-2 was evaluated with the Enzyme-Linked ImmunoSpot assay. Mann-Whitney U-test was used to compare the T cell responses from different groups. Spearman＇s rank correlation was used to analyze the relationship of T cell responses. Results： HLA-A＊02：01, A＊02：07, and A＊24：02 were the three most frequent alleles （18.9%, 12.3%, and 11.5%, respectively） among the 22 detected alleles. 31.1%, 19.7%, and 16.4% of the patients displayed MAGE-A1, MAGE-A3, or SSX-2-specific T cell response, respectively. The magnitudes of response to the three proteins were 32.5, 38.0, and 28.7 SFC/106 peripheral blood mononuclear cells, respectively. The T cell response against the three proteins correlated with each other to different extent. The percentage of A＊02：01 and A＊24：02 carriers were significantly higher in patients responding to any of the three proteins compared to the nonresponders. Conclusion： MAGE-A1, MAGE-A3, or SSX-2-specific T cell responses were detectable in a subgroup of NPC patients, the frequency and magnitude of which were correlated.

Early gastric cancer frequently has high expression of KKLC-1, a cancer-testis antigen

AIM To assess cancer-testis antigens(CTAs) expression in gastric cancer patients and examined their associations with clinicopathological factors.METHODS Eighty-three gastric cancer patients were evaluated in this study. Gastric cancer specimens were evaluated for the gene expression of CTAs, Kitakyushu lung cancer antigen-1(KK-LC-1), melanoma antigen(MAGE)-A1, MAGE-A3 and New York esophageal cancer-1(NYESO-1), by reverse transcription PCR. Clinicopathological background information, such as gender, age, tumor size, macroscopic type, tumor histology, depth of invasion, lymph node metastasis, lymphatic invasion, venous invasion, and pathological stage, was obtained. Statistical comparisons between the expression of each CTA and each clinicopathological background were performed using the χ2 test. RESULTS The expression rates of KK-LC-1, MAGE-A1, MAGE-A3, and NY-ESO-1 were 79.5%, 32.5%, 39.8%, and 15.7%, respectively. In early stage gastric cancer specimens, the expression of KK-LC-1 was 79.4%, which is comparable to the 79.6% observed in advanced stage specimens. The expression of KK-LC-1 was not significantly associated with clinicopathological factors, while there were considerable differences in the expression rates of MAGE-A1 and MAGE-A3 with vs without lymphatic invasion(MAGE-A1, 39.3% vs 13.6%, P = 0.034; MAGE-A3, 47.5% vs 18.2%, P = 0.022) and/or vascular invasion(MAGE-A1, 41.5% vs 16.7%, P = 0.028; MAGE-A3, 49.1% vs 23.3%, P = 0.035) and, particularly, MAGE-A3, in patients with early vs advanced stage(36.5% vs 49.0%, P = 0.044), respectively. Patients expressing MAGE-A3 and NYESO-1 were older than those not expressing MAGE-A3 and NY-ESO-1(MAGE-A3, 73.7 ± 7.1 vs 67.4 ± 12.3, P = 0.009; NY-ESO-1, 75.5 ± 7.2 vs 68.8 ± 11.2, P = 0.042). CONCLUSION The KK-LC-1 expression rate was high even in patients with stage I cancer, suggesting that KK-LC-1 is a useful biomarker for early diagnosis of gastric cancer.

MAGE-C3 promotes cancer metastasis by inducing epithelial-mesenchymal transition and immunosuppression in esophageal squamous cell carcinoma

Background:Evading immune surveillance is necessary for tumor metastasis.Thus,there is an urgent need to better understand the interaction between metastasis and mechanisms of tumor immune evasion.In this study,we aimed to clarify a novel mechanism that link tumor metastasis and immunosuppression in the development of esophageal squamous cell carcinoma(ESCC).Methods:The expression of melanoma-associated antigen C3(MAGE-C3)was detected using immunohistochemistry.Transwell assays were used to evaluate the migration and invasion ability of esophageal squamous cell carcinoma(ESCC)cells.Metastasis assays in mice were used to evaluate metastatic ability in vivo.Lymphocyte-mediated cytotoxicity assays were performed to visualize the immune suppression function on tumor cells.RNA sequencing was performed to identify differentially expressed genes between MAGE-C3 overexpressing ESCC cells and control cells.Gene ontology(GO)enrichment analyses was performed to identify the most altered pathways influenced by MAGE-C3.The activation of the interferon-γ(IFN-γ)pathway was analyzed using Western blotting,GAS luciferase reporter assays,immunofluorescence,and flow cytometry.The role of MAGE-C3 in the IFN-γpathway was determined by Western blotting and immunoprecipitation.Furthermore,immunohistochemistry and flow cytometry analysis monitored the changes of infiltrated T cell populations in murine lung metastases.Results:MAGE-C3 was overexpressed in ESCC tissues.High expression of MAGE-C3 had a significant association with the risk of lymphatic metastasis and poor survival in patients with ESCC.Functional experiments revealed that MAGE-C3 promoted tumor metastasis by activating the epithelial-mesenchymal transition(EMT).MAGE-C3 repressed antitumor immunity and regulated cytokine secretion of T cells,implying an immunosuppressive function.Mechanistically,MAGE-C3 facilitated IFN-γsignaling and upregulated programmed cell death ligand 1(PDŋL1)by binding with IFN-γreceptor 1(IFNGR1)and strengthening the interaction between IFNGR1 and signal transducer and activator of transcription 1(STAT1).Interestingly,MAGE-C3 displayed higher tumorigenesis in immune-competent mice than in immune-deficient nude mice,confirming the immunosuppressive role of MAGE-C3.Furthermore,mice bearing MAGE-C3-overexpressing tumors showed worse survival and more lung metastases with decreased CD8+infiltrated T cells and increased programmed cell death 1(PD-1)^(+)CD8^(+) infiltrated T cells.Conclusion:MAGE-C3 enhances tumor metastasis through promoting EMT and protecting tumors from immune surveillance,and could be a potential prognostic marker and therapeutic target.